NF-κB is involved in the LPS-mediated proliferation and apoptosis of MAC-T epithelial cells as part of the subacute ruminal acidosis response in cows.

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Fan, Wen-Jie; Li, He-Ping; Zhu, He-Shui; Sui, Shi-Ping; Chen, Pei-Ge; Deng, Yue; Sui, Tong-Ming; Wang, Yue-Ying

2016-11-01

To determine the effect of NF-κB on cell proliferation and apoptosis, we investigate the expression of inflammation and apoptosis-related factors in the bovine mammary epithelial cell line, MAC-T. MAC-T cells were cultured in vitro and MTT and LDH assays used to determine the effects of lipopolysaccharide (LPS) on proliferation and cytotoxicity respectively. RT-PCR and western blotting were used to evaluate the effect of LPS and NF-κB inhibition [pyrrolidine dithiocarbamate (PDTC) treatment] on the expression of inflammation and apoptosis-related factors. LPS significantly inhibited MAC-T cell proliferation in a dose- and time-dependent manner. Furthermore, LPS promoted apoptosis while the NF-кB inhibitor PDTC attenuated this effect. After LPS treatment, the NF-кB signaling pathway was activated, and the expression of inflammation and apoptosis-related factors increased. When PDTC blocked NF-кB signaling, the expression of inflammation and apoptosis-related factors were decreased in MAC-T cells. LPS activates the TLR4/NF-κB signaling pathway, inhibits proliferation and promotes apoptosis in MAC-T cells. NF-кB inhibition attenuates MAC-T cell apoptosis and TLR4/NF-κB signaling pathway. NF-кB inhibitor alleviating MAC-T cell apoptosis is presumably modulated by NF-кB.

Collagen gel protects L929 cells from TNFα-induced death by activating NF-κB.

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Wang, Hong-Ju; Li, Meng-Qi; Liu, Wei-Wei; Hayashi, Toshihiko; Fujisaki, Hitomi; Hattori, Shunji; Tashiro, Shin-Ichi; Onodera, Satoshi; Ikejima, Takashi

2017-09-01

Type I collagen is one of the most abundant components of extracellular matrix. We previously illustrated that murine fibrosarcoma L929 cells grew well on type I collagen gel and escaped from TNFα-induced cell death. In this study, we investigated the mechanism underlying the protective effect of collagen gel. We used western blot, confocal microscopy, MTT assay and flow cytometry by introducing fluorescence staining to determine the expression levels of nuclear factor kappa B (NF-κB), inhibitory ratio and autophagy. L929 cells on collagen gel showed higher expression of NF-κB in the nucleus. Inhibition of NF-κB with pyrrolidine dithiocarbamate hydrochloride (PDTC) or knockdown by NF-κB-siRNA canceled the protective effect of collagen gel on L929 cells from TNFα-induced death, suggesting for the role of NF-κB in the protection from cell death. We found a new aspect of the effect of PDTC on L929 cells cultured on collagen gel. PDTC alone without TNFα induced apoptosis in the L929 cells cultured on collagen gel but not the cells on plastic dish. The apoptosis induction of the L929 cells cultured on collagen gel with PDTC was repressed by inhibiting autophagy with chloroquine, an autophagy inhibitor, suggesting that autophagy contributes to the death induced by the treatment with PDTC. Possible underlying mechanism of this finding is discussed. NF-κB played an important role in protecting the L929 cells cultured on collagen gel from TNFα-induced death.

Effect of nuclear factor kappa B on intercellular adhesion molecule-1 expression and neutrophil infiltration in lung injury induced by intestinal ischemia/reperfusion in rats

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Tian, Xiao-Feng; Yao, Ji-Hong; Li, Ying-Hua; Zhang, Xue-Song; Feng, Bing-An; Yang, Chun-Ming; Zheng, Shu-Sen

2006-01-01

AIM: To investigate the role of nuclear factor kappa B (NF-κB) in the pathogenesis of lung injury induced by intestinal ischemia/reperfusion (I/R), and its effect on intercellular adhesion molecule-1 (ICAM-1) expression and neutrophil infiltration. METHODS: Twenty-four Wistar rats were divided randomly into control, I/R and pyrrolidine dithiocarbamate (PDTC) treatment groups, n = 8 in each. I/R group and PDTC treatment group received superior mysenteric artery (SMA) occluding for 1 h and reperfusion for 2 h. PDTC group was administrated with intraperitoneal injection of 2% 100 mg/kg PDTC 1 h before surgery. Lung histology and bronchia alveolus lung fluid (BALF) protein were assayed. Serum IL-6, lung malondialdehyde (MDA) and myeloperoxidase (MPO) as well as the expression level of NF-κB and ICAM-1 were measured. RESULTS: Lung injury induced by intestinal I/R, was characterized by edema, hemorrhage and neutrophil infiltration as well as by the significant rising of BALF protein. Compared to control group, the levels of serum IL-6 and lung MDA and MPO increased significantly in I/R group (P = 0.001). Strong positive expression of NF-κB p65 and ICAM-1 was observed. After the administration of PDTC, the level of serum IL-6, lung MDA and MPO as well as NF-κB and ICAM-1 decreased significantly (P < 0.05) when compared to I/R group. CONCLUSION: The activation of NF-κB plays an important role in the pathogenesis of lung injury induced by intestinal I/R through upregulating the neutrophil infiltration and lung ICAM-1 expression. PDTC as an inhibitor of NF-κB can prevent lung injury induced by intestinal I/R through inhibiting the activity of NF-κB. PMID:16489637

Nuclear Factor-Kappa B Activity Regulates Brain Expression of P-Glycoprotein in the Kainic Acid-Induced Seizure Rats

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Nian Yu

2011-01-01

Full Text Available This study was aimed to investigate the effect of NF-κB activity on the seizure susceptibility, brain damage, and P-gp expression in kainic acid- (KA- induced seizure rats. Male SD rats were divided into saline control group (NS group, KA induced epilepsy group (EP group, and epilepsy group intervened with NF-κB inhibitor-pyrrolidine dithiocarbamate salt (PDTC group or with dexamethasone (DEX group. No seizures were observed in the rats of NS group. Compared with NS group, increased P-gp expression and NF-κB activation in the rat brain of the EP group were observed after KA micro-injection. Both PDTC and DEX pre-treatment significantly increased the latency to grade III or V seizure onset compared to EP group but failed to show neuron-protective effect as the number of survival neurons didn't significantly differ from that in EP group. Furthermore, PDTC pre-treatment significantly decreased P-gp expression along with NF-κB activation in the hippocampus CA3 area and amygdala complex of rats compared with the EP group, implying that NF-κB activation involved in the seizure susceptibility and seizure induced brain P-gp over-expression. Additionally, DEX pre-treatment only decreased P-gp expression level without inhibition of NF-κB activation, suggesting NF-κB independent pathway may also participate in regulating seizure induced P-gp over-expression.

Inhibitory Effects of Ethyl Acetate Extract of Andrographis paniculata on NF-κB Trans-Activation Activity and LPS-Induced Acute Inflammation in Mice

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Wen-Wan Chao

2011-01-01

Full Text Available This study was to investigate anti-inflammatory effect of Andrographis paniculata (Burm. f. Nees (Acanthaceae (AP. The effects of ethyl acetate (EtOAc extract from AP on the level of inflammatory mediators were examined first using nuclear factor kappa B (NF-κB driven luciferase assay. The results showed that AP significantly inhibited NF-κB luciferase activity and tumor necrosis factor α (TNF-α, interleukin 6 (IL-6, macrophage inflammatory protein-2 (MIP-2 and nitric oxide (NO secretions from lipopolysaccharide (LPS/interferon-γ stimulated Raw264.7 cells. To further evaluate the anti-inflammatory effects of AP in vivo, BALB/c mice were tube-fed with 0.78 (AP1, 1.56 (AP2, 3.12 (AP3 and 6.25 (AP4 mg kg−1 body weight (BW/day in soybean oil, while the control and PDTC (pyrrolidine dithiocarbamate, an anti-inflammatory agent groups were tube-fed with soybean oil only. After 1 week of tube-feeding, the PDTC group was injected with 50 mg kg−1 BW PDTC and 1 h later, all of the mice were injected with 15 mg kg−1 BW LPS. The results showed that the AP1, AP2, AP3 and PDTC groups, but not AP4, had significantly higher survival rate than the control group. Thus, the control, AP1, AP2, AP3 and PDTC groups were repeated for in vivo parameters. The results showed that the AP and PDTC groups had significantly lower TNF-α, IL-12p40, MIP-2 or NO in serum or peritoneal macrophages and infiltration of inflammatory cells into the lung of mice. The AP1 group also had significantly lower MIP-2 mRNA expression in brain. This study suggests that AP can inhibit the production of inflammatory mediators and alleviate acute hazards at its optimal dosages.

Physiological and molecular genetic evaluation of the dechlorination agent, pyridine-2,6-bis(monothiocarboxylic acid) (PDTC) as a secondary siderophore of Pseudomonas.

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Lewis, Thomas A; Leach, Lynne; Morales, Sergio; Austin, Paula R; Hartwell, Hadley J; Kaplan, Benjamin; Forker, Cynthia; Meyer, Jean-Marie

2004-02-01

The bacterial metabolite and transition metal chelator pyridine-2,6-dithiocarboxylic acid (PDTC), promotes a novel and effective means of dechlorination of the toxic and carcinogenic pollutant, carbon tetrachloride. Pyridine-2,6-dithiocarboxylic acid has been presumed to act as a siderophore in the Pseudomonas strains known to produce it. To explore further the physiological function of PDTC production, we have examined its regulation, the phenotype of PDTC-negative (pdt) mutants, and envelope proteins associated with PDTC in P. putida strain DSM 3601. Aspects of the regulation of PDTC production and outer membrane protein composition were consistent with siderophore function. Pyridine-2,6-dithiocarboxylic acid production was coordinated with production of the well-characterized siderophore pyoverdine; exogenously added pyoverdine led to decreased PDTC production, and added PDTC led to decreased pyoverdine production. Positive regulation of a chromosomal pdtI-xylE transcriptional fusion, and of a 66 kDa outer membrane protein (IROMP), was seen in response to exogenous PDTC. Tests with transition metal chelators indicated that PDTC could provide a benefit under conditions of metal limitation; the loss of PDTC biosynthetic capacity caused by a pdtI transposon insertion resulted in increased sensitivity to 1,10-phenanthroline, a chelator that has high affinity for a range of divalent transition metals (e.g. Fe(2+), Cu(2+), Zn(2+)). Exogenously added PDTC could also suppress a phenotype of pyoverdine-negative (Pvd-) mutants, that of sensitivity to EDDHA, a chelator with higher affinity and specificity for Fe(3+). Measurement of 59Fe incorporation showed uptake from 59Fe:PDTC by DSM 3601 grown in low-iron medium, but not by cells grown in high iron medium, or by the pdtI mutant, which did not show expression of the 66 kDa envelope protein. These data verified a siderophore function for PDTC, and have implicated it in the uptake of transition metals in addition to iron.

Activation of NF-κB is involved in 6-hydroxydopamine-but not MPP+-induced dopaminergic neuronal cell death: its potential role as a survival determinant

International Nuclear Information System (INIS)

Park, Seong H.; Choi, Won-Seok; Yoon, So-Young; Ahn, Young Soo; Oh, Young J.

2004-01-01

The nuclear factor-kappaB (NF-κB) family plays an important role in the control of the apoptotic response. Its activation has been demonstrated in both neurons and glial cells in many neurological disorders. In the present study, we specifically examined whether and to what extent NF-κB activation is involved in culture models of Parkinson's disease following exposure of MN9D dopaminergic neuronal cells to 6-hydroxydopamine (6-OHDA) and 1-methyl-4-phenyl-4-phenylpyridinium ion (MPP + ). Both analysis by immunocytochemistry and of immunoblots revealed that NF-κB-p65 was translocated into the nuclei following 6-OHDA but not MPP + -treatment. A time-dependent activation of NF-κB induced by 6-OHDA but not MPP + was also demonstrated by an electrophoretic mobility shift assay. A competition assay indicated that not only NF-κB-p65 but also -p50 is involved in 6-OHDA-induced NF-κB activity. Co-treatment with an antioxidant, N-acetyl-L-cysteine, blocked 6-OHDA-induced activation of NF-κB signaling. In the presence of an NF-κB inhibitor, pyrrolidine dithiocarbamate (PDTC), 6-OHDA-induced cell death was accelerated while PDTC did not affect MPP + -induced cell death. Our data may point to a drug-specific activation of NF-κB as a survival determinant for dopaminergic neurons

Reduced resting potentials in dystrophic (mdx) muscle fibers are secondary to NF-κB-dependent negative modulation of ouabain sensitive Na+-K+ pump activity.

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Miles, M T; Cottey, E; Cottey, A; Stefanski, C; Carlson, C G

2011-04-15

To examine potential mechanisms for the reduced resting membrane potentials (RPs) of mature dystrophic (mdx) muscle fibers, the Na(+)-K(+) pump inhibitor ouabain was added to freshly isolated nondystrophic and mdx fibers. Ouabain produced a 71% smaller depolarization in mdx fibers than in nondystrophic fibers, increased the [Na(+)](i) in nondystrophic fibers by 40%, but had no significant effect on the [Na(+)](i) of mdx fibers, which was approximately double that observed in untreated nondystrophic fibers. Western blots indicated no difference in total and phosphorylated Na(+)-K(+) ATPase catalytic α1 subunit between nondystrophic and mdx muscle. Examination of the effects of the NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC) indicated that direct application of the drug slowly hyperpolarized mdx fibers (7 mV in 90 min) but had no effect on nondystrophic fibers. Pretreatment with ouabain abolished this hyperpolarization, and pretreatment with PDTC restored ouabain-induced depolarization and reduced [Na(+)](i). Administration of an NF-κB inhibitor that utilizes a different mechanism for reducing nuclear NF-κB activation, ursodeoxycholic acid (UDCA), also hyperpolarized mdx fibers. These results suggest that in situ Na(+)-K(+) pump activity is depressed in mature dystrophic fibers by NF-κB dependent modulators, and that this reduced pump activity contributes to the weakness characteristic of dystrophic muscle. Copyright © 2011 Elsevier B.V. All rights reserved.

Inhibition of NF-κB promotes autophagy via JNK signaling pathway in porcine granulosa cells

International Nuclear Information System (INIS)

Gao, Hui; Lin, Lu; Haq, Ihtesham Ul; Zeng, Shen-ming

2016-01-01

The transcription factor nuclear factor-κB (NF-κB) plays an important role in diverse processes, including cell proliferation and differentiation, apoptosis and inflammation. However, the role of NF-κB in porcine follicle development is not clearly elucidated. In this study, we demonstrated that follicle stimulating hormone (FSH) increased the level of inhibitor of NF-κB (IκB) protein and promoted the cytoplasmic localization of p65, indicating that FSH inhibits the activation of NF-κB in porcine granulosa cells. Moreover, inhibition of NF-κB by FSH or another specific inhibitor of NF-κB, pyrrolidine dithiocarbamate (PDTC), could activate JNK signaling and enhance autophagic activity in porcine granulosa cells. Knockdown of RelA (p65) Subunit of NF-κB by RNA interference abrogated the activation of JNK signaling pathway and the increase of autophagic protein expression by FSH. Meanwhile, the functional significance of FSH or PDTC-mediated autophagy were further investigated. Our results demonstrated that the increased autophagy promoted progesterone secretion in porcine granulosa cells. Blockage of autophagy by chloroquine obviated the FSH or PDTC-induced progesterone production. Taken together, these results indicate that inhibition of NF-κB increased autophagy via JNK signaling, and promote steroidogenesis in porcine granulosa cells. Our results provide new insights into the regulation and function of autophagy in mammalian follicle development. - Highlights: • FSH inhibits the activation of NF-κB in porcine primary granulosa cells. • Inhibition of NF-κB by FSH promotes autophagy via JNK signaling in granulosa cells. • Increased autophagy contributes to progesterone production in granulosa cells. • This is the first report against beclin1 regulation in porcine granulosa cells.

Inhibition of NF-κB promotes autophagy via JNK signaling pathway in porcine granulosa cells

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Gao, Hui; Lin, Lu; Haq, Ihtesham Ul; Zeng, Shen-ming, E-mail: zengshenming@gmail.com

2016-04-22

The transcription factor nuclear factor-κB (NF-κB) plays an important role in diverse processes, including cell proliferation and differentiation, apoptosis and inflammation. However, the role of NF-κB in porcine follicle development is not clearly elucidated. In this study, we demonstrated that follicle stimulating hormone (FSH) increased the level of inhibitor of NF-κB (IκB) protein and promoted the cytoplasmic localization of p65, indicating that FSH inhibits the activation of NF-κB in porcine granulosa cells. Moreover, inhibition of NF-κB by FSH or another specific inhibitor of NF-κB, pyrrolidine dithiocarbamate (PDTC), could activate JNK signaling and enhance autophagic activity in porcine granulosa cells. Knockdown of RelA (p65) Subunit of NF-κB by RNA interference abrogated the activation of JNK signaling pathway and the increase of autophagic protein expression by FSH. Meanwhile, the functional significance of FSH or PDTC-mediated autophagy were further investigated. Our results demonstrated that the increased autophagy promoted progesterone secretion in porcine granulosa cells. Blockage of autophagy by chloroquine obviated the FSH or PDTC-induced progesterone production. Taken together, these results indicate that inhibition of NF-κB increased autophagy via JNK signaling, and promote steroidogenesis in porcine granulosa cells. Our results provide new insights into the regulation and function of autophagy in mammalian follicle development. - Highlights: • FSH inhibits the activation of NF-κB in porcine primary granulosa cells. • Inhibition of NF-κB by FSH promotes autophagy via JNK signaling in granulosa cells. • Increased autophagy contributes to progesterone production in granulosa cells. • This is the first report against beclin1 regulation in porcine granulosa cells.

Pharmacological Inhibition of Macrophage Toll-like Receptor 4/Nuclear Factor-kappa B Alleviates Rhabdomyolysis-induced Acute Kidney Injury.

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Huang, Rong-Shuang; Zhou, Jiao-Jiao; Feng, Yu-Ying; Shi, Min; Guo, Fan; Gou, Shen-Ju; Salerno, Stephen; Ma, Liang; Fu, Ping

2017-09-20

Acute kidney injury (AKI) is the most common and life-threatening systemic complication of rhabdomyolysis. Inflammation plays an important role in the development of rhabdomyolysis-induced AKI. This study aimed to investigate the kidney model of AKI caused by rhabdomyolysis to verify the role of macrophage Toll-like receptor 4/nuclear factor-kappa B (TLR4/NF-κB) signaling pathway. C57BL/6 mice were injected with a 50% glycerin solution at bilateral back limbs to induce rhabdomyolysis, and CLI-095 or pyrrolidine dithiocarbamate (PDTC) was intraperitoneally injected at 0.5 h before molding. Serum creatinine levels, creatine kinase, the expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6, and hematoxylin and eosin stainings of kidney tissues were tested. The infiltration of macrophage, mRNA levels, and protein expression of TLR4 and NF-κB were investigated by immunofluorescence double-staining techniques, reverse transcriptase-quantitative polymerase chain reaction, and Western blotting, respectively. In vitro, macrophage RAW264.7 was stimulated by ferrous myoglobin; the cytokines, TLR4 and NF-κB expressions were also detected. In an in vivo study, using CLI-095 or PDTC to block TLR4/NF-κB, functional and histologic results showed that the inhibition of TLR4 or NF-κB alleviated glycerol-induced renal damages (P rhabdomyolysis-induced AKI by the regulation of proinflammatory cytokine production and macrophage infiltration.

Construction of green fluorescent protein-tagged recombinant iridovirus to assess viral replication.

Science.gov (United States)

Huang, Youhua; Huang, Xiaohong; Cai, Jia; Ye, Fuzhou; Guan, Liya; Liu, Hong; Qin, Qiwei

2011-09-01

Green fluorescent protein-tagged recombinant virus has been successfully applied to observing the infective dynamics and evaluating viral replication. Here, we identified soft-shelled turtle iridovirus (STIV) ORF55 as an envelope protein (VP55), and developed a recombinant STIV expressing an enhanced green fluorescent protein (EGFP) fused to VP55 (EGFP-STIV). Recombinant EGFP-STIV shared similar single-step growth curves and ultrastructural morphology with wild type STIV (wt-STIV). The green fluorescence distribution during EGFP-STIV infection was consistent with the intracellular distribution of VP55 which was mostly co-localized with virus assembly sites. Furthermore, EGFP-STIV could be used to evaluate viral replication conveniently under drug treatment, and the result showed that STIV replication was significantly inhibited after the addition of antioxidant pyrrolidine dithiocarbamate (PDTC). Thus, the EGFP-tagged recombinant iridovirus will not only be useful for further investigations on the viral replicative dynamics, but also provide an alternative simple strategy to screen for antiviral substances. Copyright © 2011 Elsevier B.V. All rights reserved.

Role of NFkappaB in an animal model of complex regional pain syndrome-type I (CRPS-I).

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de Mos, Marissa; Laferrière, André; Millecamps, Magali; Pilkington, Mercedes; Sturkenboom, Miriam C J M; Huygen, Frank J P M; Coderre, Terence J

2009-11-01

NFkappaB is involved in several pathogenic mechanisms that are believed to underlie the complex regional pain syndrome (CRPS), including ischemia, inflammation and sensitization. Chronic postischemia pain (CPIP) has been developed as an animal model that mimics the symptoms of CRPS-I. The possible involvement of NFkappaB in CRPS-I was studied using CPIP rats. Under sodium pentobarbital anesthesia, a tourniquet was placed around the rat left ankle joint, producing 3 hours of ischemia, followed by rapid reperfusion (IR injury). NFkappaB was measured in nuclear extracts of muscle and spinal cord tissue using ELISA. Moreover, the anti-allodynic (mechanical and cold) effect was tested for systemic, intrathecal, or intraplantar treatment with the NFkappaB inhibitor pyrrolidine dithiocarbamate (PDTC). At 2 and 48 hours after IR injury, NFkappaB was elevated in muscle and spinal cord of CPIP rats compared to shams. At 7 days, NFkappaB levels were normalized in muscle, but still elevated in spinal cord tissue. Systemic PDTC treatment relieved mechanical and cold allodynia in a dose-dependent manner, lasting for at least 3 hours. Intrathecal-but not intraplantar-administration also relieved mechanical allodynia. The results suggest that muscle and spinal NFkappaB plays a role in the pathogenesis of CPIP and potentially of human CRPS. Using the CPIP model, we demonstrate that NFkappaB is involved in the development of allodynia after a physical injury (ischemia and reperfusion) without direct nerve trauma. Since CPIP animals exhibit many features of human CRPS-I, this observation indicates a potential role for NFkappaB in human CRPS.

Improving the developability profile of pyrrolidine progesterone receptor partial agonists

Energy Technology Data Exchange (ETDEWEB)

Kallander, Lara S.; Washburn, David G.; Hoang, Tram H.; Frazee, James S.; Stoy, Patrick; Johnson, Latisha; Lu, Qing; Hammond, Marlys; Barton, Linda S.; Patterson, Jaclyn R.; Azzarano, Leonard M.; Nagilla, Rakesh; Madauss, Kevin P.; Williams, Shawn P.; Stewart, Eugene L.; Duraiswami, Chaya; Grygielko, Eugene T.; Xu, Xiaoping; Laping, Nicholas J.; Bray, Jeffrey D.; Thompson, Scott K. (GSKPA)

2010-09-17

The previously reported pyrrolidine class of progesterone receptor partial agonists demonstrated excellent potency but suffered from serious liabilities including hERG blockade and high volume of distribution in the rat. The basic pyrrolidine amine was intentionally converted to a sulfonamide, carbamate, or amide to address these liabilities. The evaluation of the degree of partial agonism for these non-basic pyrrolidine derivatives and demonstration of their efficacy in an in vivo model of endometriosis is disclosed herein.

Nicotine promotes cervical carcinoma cell line HeLa migration and invasion by activating PI3k/Akt/NF-κB pathway in vitro.

Science.gov (United States)

Wang, Chengze; Gu, Weiting; Zhang, Yunpeng; Ji, Yawen; Wen, Yong; Xu, Xin

2017-07-05

Cigarette smoking is one of highly risk factors of cervical cancer. Recently nicotine has been reported to increase proliferation and invasion in some smoking related cancers, like non-small cell lung cancer and esophageal squamous cell cancer. However, the effects and mechanisms of nicotine stimulation on cervical cancer cells are not clear. Here, we investigated the effects and mechanisms of nicotine stimulation on HeLa cells in vitro. In our study, we found that nicotine could accelerate HeLa cells migration and invasion, activate PI3K/Akt and NF-κB pathways and increase the expression of Vimentin in vitro. Moreover, we demonstrated that the specific PI3K inhibitor LY294002 could reverse nicotine-induced cell migration and invasion, NF-κB activation and up-regulation of Vimentin. Inhibition of NF-κB by Pyrrolidine dithiocarbamate (PDTC) also antagonized nicotine-induced cell migration, invasion and up-regulation of Vimentin. Simply put, these findings suggest that nicotine promotes cervical carcinoma cell line HeLa migration and invasion by activating PI3k/Akt/NF-κB pathway in vitro. Copyright © 2017 Elsevier GmbH. All rights reserved.

A modular synthesis of dithiocarbamate pendant unnatural α-amino acids

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Unnatural α-amino acids containing dithiocarbamate side chains were synthesized by a one-pot reaction of in-situ generated dithiocarbamate anions with sulfamidates. A wide range of these anions participated in the highly regio- and stereo-selective ring opening of sulfamidates to...

One-step synthesis of dithiocarbamates from metal powders

Science.gov (United States)

Hepp, Aloysius F.; Hehemann, David G.; Duraj, Stan A.; Clark, Eric B.; Eckles, William E.; Fanwick, Phillip E.

1994-01-01

Neutral metal dithiocarbamate complexes (M(NR2CS2)X) are well-known precursors to metal sulfides, a class of materials with numerous technological applications. We are involved in a research effort to prepare new precursors to metal sulfides using simple, reproducible synthetic procedures. We describe the results of our synthetic and characterization studies for M = Fe, Co, Ni, Cu. and In. For example, treatment of metallic indium with tetramethylthiuram disulfide (tmtd) in 4-methylpyridine (4-Mepy) at 25 deg C produces a new homoleptic indium (III) dithiocarbamate, In(N(CH3)2CS2)3(I), in yields of over 60 percent. The indium (III) dithiocarbamate was characterized by X-ray crystallography; (I) exists in the solid state as discrete distorted-octahedral molecules. Compound (I) crystallizes in the P1bar (No. 2) space group with lattice parameters: a = 9.282(1) A, b = 10.081(1) A, c = 12.502 A, alpha = 73.91(1) deg, beta = 70.21(1) deg, gamma = 85.8(1)deg, and Z = 2. X-ray diffraction and mass spectral data were used to characterize the products of the analogous reactions with Fe, Co, Ni, and Cu. We discuss both use of dithiocarbamates as precursors and our approach to their preparation.

The chick embryo test as used in the study of the toxicity of certain dithiocarbamates

NARCIS (Netherlands)

Gebhardt, D.O.E.; Logten, M.J. van

1968-01-01

The toxicities of six dithiocarbamates: bis(dimethyl thiocarbamoyl) disulfide (thiram), zinc dimethyldithiocarbamate (ziram), ferric dimethyldithiocarbamate (ferbam), bis(dimethyl thiocarbamoyl) ethylene bis(dithiocarbamate) (triaram), sodium diethyl dithiocarbamate (NaDEDC), and sodium ethylene

DETERMINATION OF KINETICS OF DEGRADATION AND MOBILITY OF DITHIOCARBAMATES FUNGICIDES IN AQUEOUS MEDIA AND IN MOROCCAN SOIL

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Said El Antri

2010-07-01

Full Text Available Contribution analysis of dithiocarbamates pesticides used on tomatoes treatment has been reported. The study is focused on analysis and determination of some dithiocarbamates like, Maneb, Mancozeb, Zineb and Propineb, in order to achieve accurate impact of theses pesticides on water and soil. Analysis method is based on decomposition of dithiocarbamate by heating under acidic attack to give carbon disulfide complexed with copper acetate solution in presence of diethanolamine. Complex formed is dosed spectrophotometrically at 435 nm. Degradation kinetic of dithiocarbamate in aqueous media have been realized and proved that dithiocarbamate are degraded by simple air exposition. In the other hand, pH affects also dithiocarbamate degradation by increasing hydroxyl ions to participate for dithiocarbamate instability. Dithiocarbamate mobility on Moroccan soils samples have been realised and don’t have the same degradation mode.

Synthesis and characterization of oxovanadium (IV) dithiocarbamates with pyridine

Energy Technology Data Exchange (ETDEWEB)

Doadrio, Antonio L.; Sotelo, Jose; Fernandez-Ruano, Ana [Universidad Complutense, Madrid (Spain). Facultad de Farmacia. Dept. de Quimica Inorganica y Bioinorganica]. E-mail: antoniov@farm.ucm.es

2002-07-01

We report the synthesis and study of a new series of oxovanadium (IV) dithiocarbamate adducts and derivatives with pyridine and cyclohexyl, di-iso-butyl, di-n-propyl, aniline, morpholine, piperidine and di-iso-propyl amines. The complexes have been characterized by analytical, magneto chemical, IR, visible-UV spectral and thermal studies, and are assigned the formulas [VO(L){sub 2}].py, where L=cyclohexyl, di-iso-butyl, di-n-propyl, aniline dithiocarbamate and [VO(OH)(L)(py){sub 2}] OH.H{sub 2}O (L=morpholine, piperidine and di-iso-propyl dithiocarbamate). The effect of the adduct formation on the p{sub V=0} bound is discussed in terms of the IR (V=O, V-S and V-N stretching frequencies) and electronic spectra (d-d transitions). (author)

Effects of dithiocarbamates on intestinal absorption and organ distribution of cadmium chloride in mice

International Nuclear Information System (INIS)

Andersen, O.; Nielsen, J.B.; Jones, M.M.

1989-01-01

Earlier publications have demonstrated that diethyldithiocarbamate (DDC) antagonizes the acute toxicity of injected CdCl 2 but enhances the acute toxicity of orally administered CdCl 2 , most likely due to the high lipophilicity of DDC and the complex formed with the Cd ++ ion. This study demonstrates that the hydrophilic dithiocarbamates dihydroxyethyldithiocarbamate (DHE-DTC) and N-methyl-N-glucamyl dithiocarbamate (NMG-DTC) also enhance the intestinal absorption of orally administered CdCl 2 in mice, although less efficiently than DDC. After oral as well as intraperitoneal administration 15 min. after a single oral dose of CdCl 2 the dithiocarbamates tested enhanced the intestinal cadmium uptake with a relative efficiency, DDC>DHE-DTC>NMG-DTC, which correlated to the lipophilicity of both the dithiocarbamates and the complexes formed with the Cd ++ ion. Intraperitoneal administration of DDC induced extensive changes in the relative organ distribution of absorbed cadmium, compared to the distribution of CdCl 2 administered alone. However, the only noticeable effect of administration of DHE-DTC and NMG-DTC was decreased gastrointestinal deposition of cadmium, irrespective of the administration route of the dithiocarbamates. Earlier studies have demonstrated that DDC and various other dithiocarbamates are capable of mobilizing intracellular cadmium deposits, presumably due to some lipophilicity. This study demonstrates that these dithiocarbamates may also enchance the intestinal absorption of cadmium. (author)

Radical-mediated reduction of the dithiocarbamate group under tin-free conditions.

Science.gov (United States)

McMaster, Claire; Bream, Robert N; Grainger, Richard S

2012-06-28

Reductive desulfurisation of dithiocarbamates is conveniently achieved using H(3)PO(2)-Et(3)N-ACCN in refluxing dioxane. Fused and spirocyclic β-lactams, prepared through 4-exo trig carbamoyl radical cyclisation-dithiocarbamate group transfer reactions, are reduced without fragmentation of the strained 4-membered ring. Diethyl tetraacetyl-d-glucopyranosyl dithiocarbamate is selectively reduced with or without acyloxy group migration depending on reaction conditions and choice of reductant. Deuterium incorporation from D(3)PO(2)-Et(3)N is observed for a system involving a nucleophilic radical intermediate, but not in the case of the electrophilic radical obtained through acyloxy group migration on a glucose derivative.

Autoantibodies Targeting AT1 Receptor from Patients with Acute Coronary Syndrome Upregulate Proinflammatory Cytokines Expression in Endothelial Cells Involving NF-κB Pathway

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Weijuan Li

2014-01-01

Full Text Available Our study intended to prove whether agonistic autoantibodies to angiotensin II type 1 receptor (AT1-AAs exist in patients with coronary heart disease (CHD and affect the human endothelial cell (HEC by upregulating proinflammatory cytokines expression involved in NF-κB pathway. Antibodies were determined by chronotropic responses of cultured neonatal rat cardiomyocytes coupled with receptor-specific antagonists (valsartan and AT1-EC2 as described previously. Interleukin-6 (IL-6, vascular cell adhesion molecule-1 (VCAM-1, and monocyte chemotactic protein-1 (MCP-1 expression were improved at both mRNA and protein levels in HEC, while NF-κB in the DNA level was improved detected by electrophoretic mobility shift assays (EMSA. These improvements could be inhibited by specific AT1 receptor blocker valsartan, NF-κB blocker pyrrolidine dithiocarbamate (PDTC, and specific short peptides from the second extracellular loop of AT1 receptor. These results suggested that AT1-AAs, via the AT1 receptor, induce expression of proinflammatory cytokines involved in the activation of NF-κB. AT1-AAs may play a great role in the pathogenesis of the acute coronary syndrome by mediating vascular inflammatory effects involved in the NF-κB pathway.

Spinal NF-κB and chemokine ligand 5 expression during spinal glial cell activation in a neuropathic pain model.

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Qin Yin

Full Text Available BACKGROUND: The NF-κB pathway and chemokine (C-C motif ligand 5 (CCL5 are involved in pain modulation; however, the precise mechanisms of their interactions in chronic neuropathic pain have yet to be established. METHODS: The present study examined the roles of spinal NF-κB and CCL5 in a neuropathic pain model after chronic constriction injury (CCI surgery. CCI-induced pain facilitation was evaluated using the Plantar and von Frey tests. The changes in NF-κB and CCL5 expression were analyzed by immunohistochemistry and Western blot analyses. RESULTS: Spinal NF-κB and CCL5 expression increased after CCI surgery. Repeated intrathecal infusions of pyrrolidine dithiocarbamate (PDTC, a NF-κB inhibitor decreased CCL5 expression, inhibited the activation of microglia and astrocytes, and attenuated CCI-induced allodynia and hyperalgesia. Intrathecal injection of a CCL5-neutralizing antibody attenuated CCI-induced pain facilitation and also suppressed spinal glial cell activation after CCI surgery. However, the CCL5-neutralizing antibody did not affect NF-κB expression. Furthermore, selective glial inhibitors, minocycline and fluorocitrate, attenuated the hyperalgesia induced by intrathecal CCL5. CONCLUSIONS: The inhibition of spinal CCL5 expression may provide a new method to prevent and treat nerve injury-induced neuropathic pain.

Signal regulatory protein α associated with the progression of oral leukoplakia and oral squamous cell carcinoma regulates phenotype switch of macrophages.

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Ye, Xiaojing; Zhang, Jing; Lu, Rui; Zhou, Gang

2016-12-06

Signal regulatory protein α (SIRPα) is a cell-surface protein expressed on macrophages that are regarded as an important component of the tumor microenvironment. The expression of SIRPα in oral leukoplakia (OLK) and oral squamous cell carcinoma (OSCC), and further explored the role of SIRPα on the phenotype, phagocytosis ability, migration, and invasion of macrophages in OSCC were investigated. The expression of SIRPα in OLK was higher than in OSCC, correlating with the expression of CD68 and CD163 on macrophages. After cultured with the conditioned media of oral cancer cells, the expression of SIRPα on THP-1 cells was decreased gradually. In co-culture system, macrophages were induced into M2 phenotype by oral cancer cells. Blockade of SIRPα inhibited phagocytosis ability and IL-6, TNF-α productions of macrophages. In addition, the proliferation, migration, and IL-10, TGF-β productions of macrophages were upregulated after blockade of SIRPα. Macrophages upregulated the expression of SIRPα and phagocytosis ability, and inhibited the migration and invasion when the activation of NF-κB was inhibited by pyrrolidine dithiocarbamate ammonium (PDTC). Hence, SIRPα might play an important role in the progression of OLK and oral cancer, and could be a pivotal therapeutic target in OSCC by regulating the phenotype of macrophages via targeting NF-κB.

Histamine Induces Bovine Rumen Epithelial Cell Inflammatory Response via NF-κB Pathway

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Xudong Sun

2017-06-01

Full Text Available Background/Aims: Subacute ruminal acidosis (SARA is a common disease in high-producing lactating cows. Rumenitis is the initial insult of SARA and is associated with the high concentrations of histamine produced in the rumen of dairy cows during SARA. However, the exact mechanism remains unclear. The objective of the current study is to investigate whether histamine induces inflammation of rumen epithelial cells and the underlying mechanism of this process. Methods: Bovine rumen epithelial cells were cultured and treated with different concentrations of histamine and pyrrolidine dithiocarbamate (PDTC, an NF-κB inhibitor cultured in different pH medium (pH 7.2 or 5.5. qRT-PCR, Western-blotting, ELISA and immunocytofluorescence were used to evaluate whether histamine activated the NF-κB pathway and inflammatory cytokines. Results: The results showed that histamine significantly increased the activity of IKK β and the phosphorylation levels of IκB α, as well as upregulated the mRNA and protein expression levels of NF-κB p65 in the rumen epithelial cells cultured in neutral (pH=7.2 and acidic (pH=5.5 medium. Furthermore, histamine treatment also significantly increased the transcriptional activity of NF-κB p65. High expression and transcriptional activity of NF-κB p65 significantly increased the mRNA expressions and concentrations of inflammatory cytokines, tumor necrosis factor alpha (TNF-α, interleukin 6 (IL-6 and interleukin 1 beta (IL-1β, thereby inducing the inflammatory response in bovine rumen epithelial cells. However, inhibition of NF-κB p65 by PDTC significantly decreased the expressions and concentrations of the inflammatory cytokines induced by histamine in the rumen epithelial cells cultured in the neutral and acidic medium. Conclusion: The present data indicate that histamine induces the inflammatory response of bovine rumen epithelial cells through the NF-κB pathway.

ß-Hydroxybutyrate Activates the NF-κB Signaling Pathway to Promote the Expression of Pro-Inflammatory Factors in Calf Hepatocytes

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Xiaoxia Shi

2014-01-01

Full Text Available Background/Aims: ß-hydroxybutyrate (BHBA is the major component of ketone bodies in ketosis. Dairy cows with ketosis often undergo oxidative stress. BHBA is related to the inflammation involved in other diseases of dairy cattle. However, whether BHBA can induce inflammatory injury in dairy cow hepatocytes and the potential mechanism of this induction are not clear. The NF-κB pathway plays a vital role in the inflammatory response. Methods: Therefore, this study evaluated the oxidative stress, pro-inflammatory factors and NF-κB pathway in cultured calf hepatocytes treated with different concentrations of BHBA, pyrrolidine dithiocarbamate (PDTC, an NF-κB pathway inhibitor and N-acetylcysteine (NAC, antioxidant. Results: The results showed that BHBA could significantly increase the levels of oxidation indicators (MDA, NO and iNOS, whereas the levels of antioxidation indicators (GSH-Px, CAT and SOD were markedly decreased in hepatocytes. The IKKß activity and phospho-IκBa (p-IκBa contents were increased in BHBA-treated hepatocytes. This increase was accompanied by the increased expression level and transcription activity of p65. The expression levels of NF-κB-regulated inflammatory cytokines, namely TNF-a, IL-6 and IL-1ß, were markedly increased after BHBA treatment, while significantly decreased after NAC treatment. However, the p-IκBa level and the expression and activity of p65 and its target genes were markedly decreased in the PDTC + BHBA group compared with the BHBA (1.8 mM group. Moreover, immunocytofluorescence of p65 showed a similar trend. Conclusion: The present data indicate that higher concentrations of BHBA can induce cattle hepatocyte inflammatory injury through the NF-κB signaling pathway, which may be activated by oxidative stress.

Placental transfer and fetal distribution of lead in mice after treatment with dithiocarbamates

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Danielsson, B.R.G.; Dencker, L.

1984-01-01

The distribution of i.v. administered lead ( 203 Pb-acetate; 50 nmol/kg b.w.) was studied by means of autoradiography and impulse counting in pregnant C57BL mice (day 18) treated orally with dithiocarbamates. Diethyldithiocarbamate (DEDTC), disulfuram or thiram (2 X 1) mmol/kg b.w.) or vehicle (gelatine) alone, was given by gavage 2 h before and immediately after the injection of lead. All three dithiocarbamates, especially thiram, changed the distribution pattern of lead. Thiram and DEDTC had the greatest effect at 4 h after lead administration, disulfiram at 24 h. In the mother, most notably the brain concentration increased (70-fold for thiram at 4 h) while that of erythrocytes and skeleton decreased (50- and 4-fold, respectively). The total fetal concentration unexpectedly showed only a moderate increase (proportional 2-fold for thiram), which may be due partly to the low maternal plasma lead concentration. The partition within the fetal tissues was, however, changed by the dithiocarbamates in much the same way as in the mothers, e.g, the fetal brain of thiram treated animals had increased by a factor 15, while skeletal and blood concentrations were lowered compared to controls. In melanin containing structures of the maternal and fetal eyes a dramatic increase in lead concentration resulted from dithiocarbamate treatment (lead ions are known to bind to melanin in vitro). The pattern of changes in lead distribution caused by dithiocarbamates is consistent with the formation in the body of lipid soluble lead-dithiocarbamate complexes that pass biological barriers more easily than inorganic (to brain, fetus, melanocytes etc.), probably followed by a dissociation of the complexes in the tissues. (orig.)

Synthesis and characterization of dithiocarbamate chitosan derivatives with enhanced antifungal activity.

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Qin, Yukun; Liu, Song; Xing, Ronge; Yu, Huahua; Li, Kecheng; Meng, Xiangtao; Li, Rongfeng; Li, Pengcheng

2012-06-20

In this study, ammonium dithiocarbamate chitosan (ADTCCS) and triethylene diamine dithiocarbamate chitosan (TEDADTCCS) derivatives were obtained respectively by mixing chitosan with carbon disulfide and ammonia (triethylenediamine). Their structures were confirmed by FT-IR, 1H NMR, XRD, DSC, SEM, and elemental analysis. Antifungal properties of them against the plant pathogenic fungi Fusarium oxysporum and Alternaria porri were investigated at concentrations ranged from 31.25 to 500 mg/L. The dithiocarbamate chitosan derivatives had enhanced antifungal activity compared with chitosan. Particularly, they showed obvious inhibitory effect on Fusarium oxysporum. At 500 mg/L, TEDADTCCS inhibited growth of F. oxysporum at 60.4%, stronger than polyoxin and triadimefon whose antifungal indexes were found to be 25.3% and 37.7%. The chitosan derivatives described here deserve further study for use in crop protection. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

New mono-organotin (IV) dithiocarbamate complexes

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Muthalib, Amirah Faizah Abdul; Baba, Ibrahim

2014-01-01

Eighteen new mono-organotin dithiocarbamate compounds derived each nine from methyltin(IV) and phenyltin(IV) reacted using in-situ method with various type of N-dialkylamine together with carbon disulphide with the ratio of 1:3:3. Elemental and gravimetric analysis showed that the general formula of these compounds were RSnCl[S 2 CNR′R″] 2 (R= Ph, CH 3 , R′ = CH 3 , C 2 H 5 , C 7 H 7 and R″ = C 2 H 5 , C 6 H 11 , iC 3 H 7 , C 7 H 7 ). These compounds had been characterized by infrared spectroscopy, ultraviolet spectroscopy, 1 H, 13 C NMR spectroscopy and single crystal X-ray crystallography. The infrared spectra of these compounds showed three important peaks indicating the formation of dithiocarbamate compounds, ν(C N), ν(C S) and ν(Sn-S) band which present in the region of 1444–1519, 954–1098 and 318–349 cm −1 respectively. The ultraviolet-visible spectra showed an absorption band for the π - π* transition of N C S group in the range of 253 – 259 nm due to the intramolecular charge transfer of the ligand. The 13 C NMR spectra showed an important shift for δ(N 13 CS 2 ) in the range of 196.8 – 201.9 ppm.. Single crystal X-ray diffraction studies showed three new structures with the general formula of PhSnCl[S 2 CN(Et)(i−Pr)] 2 , MeSnCl[S 2 CN(Me)(Cy)] 2 and MeSnCl[S 2 CN(i−Pr)(CH 2 Ph)] 2 . All structures having a distorted octahedral geometry set by CClS 4 donor atom from the two chelating dithiocarbamate ligands

Metal complexes of alkyl-aryl dithiocarbamates: Structural studies, anticancer potentials and applications as precursors for semiconductor nanocrystals

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Andrew, Fartisincha P.; Ajibade, Peter A.

2018-03-01

Dithiocarbamates are versatile ligands able to stabilize wide range of metal ions in their various oxidation states with the partial double bond character of Csbnd N and Csbnd S of thioureide moiety. Variation of the substituents attached to the nitrogen atom of dithiocarbamate moiety generates various intermolecular interactions, which lead to different structural arrangement in the solid state. The presence of bulky substituents on the N atom obviates the supramolecular aggregation via secondary Msbnd S interactions whereas smaller substituents encourage such aggregation that results in their wide properties and applications. Over the past decades, the synthesis and structural studies of metal complexes of dithiocarbamates have received considerable attention as potential anticancer agents with various degree of DNA binding affinity and cytotoxicity and as single molecule precursors for the preparation of semiconductor nanocrystals. In this paper, we review the synthesis, structural studies, anticancer potency and the use of alkyl-phenyl dithiocarbamate complexes as precursors for the preparation of semiconductor nanocrystals. The properties of these compounds and activities are ascribed to be due to either the dithiocarbamate moieties, the nature or type of the substituents around the dithiocarbamate backbone and the central metal ions or combination of these factors.

A concise synthesis of (R)-Bgugaine, a pyrrolidine alkaloid from Arisarum vulgare

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Majik, M.S.; Parameswaran, P.S.; Tilve, S.G.

and conversion of N-carboethoxy group to N-methyl. Keywords: pyrrolidine alkaloids, bgugaine, Wittig reaction Nitrogen containing heterocycles including pyrrolidines, piperidines and related compounds, include important biologically active compounds 1.... 18 The necessary manipulation for the conversion of aldehyde group to tetradecane chain involved application of the Wittig reaction followed by reduction of the double bond and reduction of carboethoxy group to methyl. Thus, freshly...

Synthesis and crystal structures of 5'-phenylspiro[indoline-3, 2'-pyrrolidin]-2-one derivatives

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Perumal Subbu

2011-07-01

Full Text Available Abstract Background The spiro- indole-pyrrolidine ring system is a frequently encountered structural motif in many biologically important and pharmacologically relevant alkaloids. The derivatives of spirooxindole ring systems are used as antimicrobial, antitumour agents and as inhibitors of the human NKI receptor besides being found in a number of alkaloids like horsifiline, spirotryprostatin and (+ elacomine. The recently discovered small-molecule MDM2 inhibitor MI-219 and its analogues are in advanced preclinical development as cancer therapeutics. Results In the crystal structures of the two organic compounds, 4'-Nitro-3',5'-diphenylspiro[indoline-3,2'-pyrrolidin]-2-one and 3'-(4-Methoxyphenyl- 4'-nitro -5'-phenylspiro[indoline-3,2'-pyrrolidin]-2-one, N-H···O hydrogen bonds make the R22 (8 ring motif. Further, the structures are stabilized by intermolecular hydrogen bonds. Conclusion The crystal structures of 4'-Nitro-3',5'-diphenylspiro[indoline-3,2'-pyrrolidin]-2-one and 3'-(4-Methoxyphenyl- 4'-nitro -5'-phenylspiro[indoline-3,2'-pyrrolidin]-2-one have been investigated in detail. In both the compounds, the R22(8 motif is present. Due to the substitution of methoxyphenyl instead of phenyl ring, the entire configuration is inverted with respect to the 2-oxyindole ring.

IFN-γ regulates human dental pulp stem cells behavior via NF-κB and MAPK signaling

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He, Xinyao; Jiang, Wenkai; Luo, Zhirong; Qu, Tiejun; Wang, Zhihua; Liu, Ningning; Zhang, Yaqing; Cooper, Paul R.; He, Wenxi

2017-01-01

During caries, dental pulp expresses a range of pro-inflammatory cytokines in response to the infectious challenge. Interferon gamma (IFN-γ) is a dimerized soluble cytokine, which is critical for immune responses. Previous study has demonstrated that IFN-γ at relative high concentration (100 ng/mL) treatment improved the impaired dentinogenic and immunosuppressive regulatory functions of disease-derived dental pulp stem cells (DPSCs). However, little is known about the regulatory effects of IFN-γ at relative low concentration on healthy DPSC behavior (including proliferation, migration, and multiple-potential differentiation). Here we demonstrate that IFN-γ at relatively low concentrations (0.5 ng/mL) promoted the proliferation and migration of DPSCs, but abrogated odonto/osteogenic differentiation. Additionally, we identified that NF-κB and MAPK signaling pathways are both involved in the process of IFN-γ-regulated odonto/osteogenic differentiation of DPSCs. DPSCs treated with IFN-γ and supplemented with pyrrolidine dithiocarbamate (PDTC, an NF-κB inhibitor) or SB203580 (a MAPK inhibitor) showed significantly improved potential for odonto/osteogenic differentiation of DPSCs both in vivo and in vitro. These data provide important insight into the regulatory effects of IFN-γ on the biological behavior of DPSCs and indicate a promising therapeutic strategy for dentin/pulp tissue engineering in future endodontic treatment. PMID:28098169

Protection by the gross saponins of Tribulus terrestris against cerebral ischemic injury in rats involves the NF-κB pathway

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En-ping Jiang

2011-06-01

Full Text Available The aim of this study was to investigate whether the gross saponins of Tribulus terrestris (GSTT, a traditional Chinese herbal medicine, have neuroprotective effects on rats subjected to middle cerebral artery occlusion (MCAO, through nuclear factor-κB (NF-κB pathway and inflammatory mediators. Cerebral ischemia was produced by MCAO in either untreated (control or GSTT-pretreated rats, and the animals were examined for infarct volume, cerebral edema, neuro-behavioral abnormality and pathological changes. Meanwhile, the expression of NF-κB protein in brain tissue was analyzed on Western blots and the serum levels of TNF-α and IL-1 were determined by ELISA. The experimental results demonstrated that, compared with the control MCAO group, GSTT-pretreated MCAO group had significantly reduced infarct volume, brain edema and neuro-behavioral abnormality, and lesser degree of pathologic changes in the brain, as well as had lower levels of serum TNF-α and IL-1β, and higher levels of brain NF-κB (P<0.05. Furthermore, treatment with an NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC abolished the protective effects of GSTT against MCAO-induced cerebral ischemic injury. These results indicated that GSTT's ability to protect against cerebral ischemic injury was mediated through the NF-κB signaling pathway, and that GSTT may act through inhibition of the production of inflammatory mediators.

IFN-γ regulates human dental pulp stem cells behavior via NF-κB and MAPK signaling.

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He, Xinyao; Jiang, Wenkai; Luo, Zhirong; Qu, Tiejun; Wang, Zhihua; Liu, Ningning; Zhang, Yaqing; Cooper, Paul R; He, Wenxi

2017-01-18

During caries, dental pulp expresses a range of pro-inflammatory cytokines in response to the infectious challenge. Interferon gamma (IFN-γ) is a dimerized soluble cytokine, which is critical for immune responses. Previous study has demonstrated that IFN-γ at relative high concentration (100 ng/mL) treatment improved the impaired dentinogenic and immunosuppressive regulatory functions of disease-derived dental pulp stem cells (DPSCs). However, little is known about the regulatory effects of IFN-γ at relative low concentration on healthy DPSC behavior (including proliferation, migration, and multiple-potential differentiation). Here we demonstrate that IFN-γ at relatively low concentrations (0.5 ng/mL) promoted the proliferation and migration of DPSCs, but abrogated odonto/osteogenic differentiation. Additionally, we identified that NF-κB and MAPK signaling pathways are both involved in the process of IFN-γ-regulated odonto/osteogenic differentiation of DPSCs. DPSCs treated with IFN-γ and supplemented with pyrrolidine dithiocarbamate (PDTC, an NF-κB inhibitor) or SB203580 (a MAPK inhibitor) showed significantly improved potential for odonto/osteogenic differentiation of DPSCs both in vivo and in vitro. These data provide important insight into the regulatory effects of IFN-γ on the biological behavior of DPSCs and indicate a promising therapeutic strategy for dentin/pulp tissue engineering in future endodontic treatment.

The Effect of Washing and Peeling on Reduction of Dithiocarbamates Residues in Cucumber and Tomato

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Mohammad Reza Mehrasebi

2016-03-01

Full Text Available Background: Dithiocarbamates, the main group of fungicides, are used to control about 400 pathogens in more than 70 crops. These pesticides are widely applied to crops including potato, cereal, apple, pear and leafy vegetables throughout the world since 1960. From the late 1980s, using these fungicides has caused much debate among regulators about their long-term effects on consumers and occupational users. Method: In this study the residues of Dithiocarbamates in cucumber and tomato using the colorimetric method (Keppel method was measured. Respectively 80 and 45 samples of greenhouse cucumber and tomato were collected from Zanjan vegetables center in autumns and winter 2013. The samples were analyzed in 4 treatments of: unwashed, washing with water, washing whit detergent and peeling. Result: The results showed that the average concentration of Dithiocarbamates residues in unwashed greenhouse cucumber and tomatoes were 384.5 µg/kg and 65 µg/kg respectively. 35% and 5% of unwashed and water washed cucumber and tomato samples (respectively had higher Dithiocarbamates residue than MRL recommended by Institute of Standards and Industrial Research of Iran (0.5mg/kg. Conclusion: The treatments of washing and peeling had significant effect on the reduction of Dithiocarbamates residues in the all samples.

Initiation of MMA polymerization by iniferters based on dithiocarbamates

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Jovanović Slobodan M.

2005-01-01

Full Text Available Twelve modified dithiocarbamates and a thiuramdisulfide used for the initiation of methyl methacrylate (MMA polymerization were synthesized in this study. The polymerization of MMA was followed by determine the yield and molar mass of the obtained PMMA as a function of polymerization time. Four of the synthesized dithiocarbamates S-benzyl-N,N-dibenzyldithiocarbamate, S-allyl-N,N-dibenzyldithiocarbamate S-benzyl-N,N-diisobutyldithiocarbamate and S-benzoyl-N,N-diisobutyldithiocarbamate, as well as N,N,N',N'-tetrabenzylthiuramdisulfide acted as iniferters. They were active as the initiators of the photo and/or thermally initiated radical polymerization of MMA in bulk and inert solvents (benzene and toluene. S Benzyl - N,N - dibenzyldithiocarbamate can be successfully used for the initiation of MMA polymerization in a polar solvent such as dimethylacetamide.

Effect of Some Dithiocarbamate Compounds in Irradiated Rats: Mechanism of Action

International Nuclear Information System (INIS)

Moustafa, E.M.M.

2013-01-01

The objective of this study is to give more information about the role of dithiocarbamates as antioxidant in radiation-protection. Three dithiocarbamates were selected: diethyldithiocarbamate (DEDC), thiram (TD) and dimethyldithiocarbamate (DMDC). Irradiation was performed by whole body exposure of rats to 1Gy of γ-irradiation 3 times /week up to a total dose of 9 Gy. Irradiated rats received, via gavages, 100 mg/Kg body weight, of the selected dithiocarbamates, 30 min before exposure to each dose. Animals were sacrificed at 2 weeks and 3 weeks after the last irradiation dose. The results obtained in animals treated with Thiram or its metabolite dimethyldithiocarbamate (DMDC) and combination with γ-radiation showed dramatic results of all parameters and revealed synergistic effect of combination between them. Sever antioxidant and detoxification enzyme depletion. Beside DNA fragmentation was highly recognized in tail DNA % (comet assay), in addition to deterioration in liver enzymes. On the other hand, Diethyl dithiocarbamates has significantly ameliorated radiation-induced oxidative stress in brain and liver tissues. The activity levels of the antioxidant enzymes reduced glutathione (GSH) content, glutathione peroxidase (GSH-Px) and glutathione reductase (GR), the superoxide dismutase (SOD) and catalase (CAT) were significantly ameliorated associated with a significant decrease in malondialdehyde (MDA) level. In addition, the administration of diethyldithiocarbamate has significantly ameliorated the radiation-induced changes in the activity of the detoxifying enzymes; glutathione-S-transferase (GST), acetylcholinesterase (AChE), paraoxonase (PON), arylesterase (AE), and carboxylesterase activity (CE) which tends to record normal values. Diethyldithiocarbamate have also shown protection against the radiation-induced deoxyribonucleic acid (DNA) fragmentation level. However, DEDT at low doses was the more efficient in radiation protection.

Punigratane, a novel pyrrolidine alkaloid from Punica granatum rind with putative efflux inhibition activity.

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Rafiq, Zumaana; Narasimhan, Sreevidya; Vennila, Rosy; Vaidyanathan, Rama

2016-02-25

A new pyrrolidine alkaloid named Punigratane was isolated from the rind of Punica granatum. This is the first report of a pyrrolidine-like structure from the rind. The activity of this compound was tested in a representative MDR Klebsiella pneumoniae strain which exhibited high efflux pump activity. At a concentration of 6 mg, this compound Punigratane was found to have efflux inhibition activity.

Synthesis and radioprotective study of novel amino-alkyl dithiocarbamic acid derivatives against γ-irradiation in mice

International Nuclear Information System (INIS)

Hosseinimehr, S. J.; Beiki, D.; Kebriaeezadeh, A.; Khalaj, A.; Pirali Hamedani, M.; Akhlaghpoor, S.; Esmaeili, H.; Barazesh, A. R.

2009-01-01

The aim of this study was to evaluate the radioprotective capacity of some novel amino alkylated dithiocarbamic acid potassium salts against γ-irradiation in mice. Materials and Methods: Eight compounds containing 2-aminoethyl-, 3-aminopropyl-, 4-aminobutyl-, 5-aminopentyl-, 6-aminohexyl-, 7-amino heptyl-, 8-amino octyl and 9-amino nonyl of dithiocarbamate derivatives were prepared. Male NMRI mice were injected intraperitoneally with a geometric progression of doses (300 -1000 mg/kg), through the dose response range for lethal toxicity. To evaluate the radioprotective activity, one-half of the toxic LD 50 of each compound were injected intraperitoneally to groups of twenty mice, 30 minutes prior to γ-irradiation. The treated animals were kept for 30 days, and the lethality was recorded each day. Results: Among Eight compounds of alkyl dithiocarbamic acid derivatives, 5-aminopentyl, 7-amino heptyl, 8-amino octyl and 9-amino nonyl dithiocarbamic acid mono potassium salts are new compounds. All evaluated compounds showed a concentration dependent effect on the survival in mice. The LD 50 values were found to be more than 599 mg/kg. The percentages of 30-day survival of mice for 2-aminoethyl, 7-amino heptyl and 8-amino octyl dithiocarbamic acid derivatives were 7%, 40% and 13.5%, respectively, when injected 30 minutes before γ-irradiation. Other compounds had no radioprotective effects. Statistical analysis showed a significant difference between the treated and control groups for the 7-amino heptyl derivative (p<0.05). Conclusion: Among the compounds investigated in this study, 7-amino heptyl dithiocarbamate derivative showed more radioprotective effects in comparison with the others. Although it seems that the radioprotective effects in these derivatives correlate with the size of the alkyl chain, more experiments are required to support this hypothesis.

Enhanced expression of two discrete isoforms of matrix metalloproteinase-2 in experimental and human diabetic nephropathy.

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Sang Soo Kim

Full Text Available We recently reported on the enhanced expression of two isoforms of matrix metalloproteinase-2 (MMP-2 in human renal transplantation delayed graft function. These consist of the conventional secreted, full length MMP-2 isoform (FL-MMP-2 and a novel intracellular N-Terminal Truncated isoform (NTT-MMP-2 generated by oxidative stress-mediated activation of an alternate promoter in the MMP-2 first intron. Here we evaluated the effect of hyperglycemia and diabetes mellitus on the in vitro and in vivo expression of the two MMP-2 isoforms.We quantified the abundance of the FL-MMP-2 and NTT-MMP-2 transcripts by qPCR in HK2 cells cultured in high glucose or 4-hydroxy-2-hexenal (HHE and tested the effects of the NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC. The streptozotocin (STZ murine model of Type I diabetes mellitus and renal biopsies of human diabetic nephropathy were used in this study.Both isoforms of MMP-2 in HK2 cells were upregulated by culture in high glucose or with HHE. PDTC treatment did not suppress high glucose-mediated FL-MMP-2 expression but potently inhibited NTT-MMP-2 expression. With STZ-treated mice, renal cortical expression of both isoforms was increased (FL-MMP-2, 1.8-fold; NTT-MMP-2, greater than 7-fold. Isoform-specific immunohistochemical staining revealed low, but detectable levels of the FL-MMP-2 isoform in controls, while NTT-MMP-2 was not detected. While there was a modest increase in tubular epithelial cell staining for FL-MMP-2 in STZ-treated mice, NTT-MMP-2 was intensely expressed in a basolateral pattern. FL-MMP-2 and NTT-MMP-2 isoform expression as quantified by qPCR were both significantly elevated in renal biopsies of human diabetic nephropathy (12-fold and 3-fold, respectively.The expression of both isoforms of MMP-2 was enhanced in an experimental model of diabetic nephropathy and in human diabetic nephropathy. Selective MMP-2 isoform inhibition could offer a novel approach for the treatment of diabetic renal

Inhibition of NF-κB activity in the hypothalamic paraventricular nucleus attenuates hypertension and cardiac hypertrophy by modulating cytokines and attenuating oxidative stress

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Yu, Xiao-Jing [Department of Physiology and Pathophysiology, Xi' an Jiaotong University School of Basic Medical Sciences, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University Health Science Center, Xi' an 710061 (China); Zhang, Dong-Mei [Department of Physiology, Dalian Medical University, Dalian 116044 (China); Jia, Lin-Lin; Qi, Jie; Song, Xin-Ai; Tan, Hong [Department of Physiology and Pathophysiology, Xi' an Jiaotong University School of Basic Medical Sciences, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University Health Science Center, Xi' an 710061 (China); Cui, Wei [Department of Endocrinology and Metabolism, First Affiliated Hospital of Xi' an Jiaotong University, Xi' an Jiaotong University Health Science Center, Xi' an 710061 (China); Chen, Wensheng [Department of Cardiovascular Surgery, Xijing Hospital, Fourth Military Medical University, Xi' an 710032 (China); Zhu, Guo-Qing [Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing 210029 (China); Qin, Da-Nian, E-mail: dnqin@stu.edu.cn [Department of Physiology, Shantou University Medical College, Shantou 515041 (China); Kang, Yu-Ming, E-mail: ykang@mail.xjtu.edu.cn [Department of Physiology and Pathophysiology, Xi' an Jiaotong University School of Basic Medical Sciences, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University Health Science Center, Xi' an 710061 (China)

2015-05-01

We hypothesized that chronic inhibition of NF-κB activity in the hypothalamic paraventricular nucleus (PVN) delays the progression of hypertension and attenuates cardiac hypertrophy by up-regulating anti-inflammatory cytokines, reducing pro-inflammatory cytokines (PICs), attenuating nuclear factor-κB (NF-κB) p65 and NAD(P)H oxidase in the PVN of young spontaneously hypertensive rats (SHR). Young normotensive Wistar–Kyoto (WKY) and SHR rats received bilateral PVN infusions with NF–κB inhibitor pyrrolidine dithiocarbamate (PDTC) or vehicle for 4 weeks. SHR rats had higher mean arterial pressure and cardiac hypertrophy as indicated by increased whole heart weight/body weight ratio, whole heart weight/tibia length ratio, left ventricular weight/tibia length ratio, cardiomyocyte diameters of the left cardiac ventricle, and mRNA expressions of cardiac atrial natriuretic peptide (ANP) and beta-myosin heavy chain (β-MHC). These SHR rats had higher PVN levels of proinflammatory cytokines (PICs), reactive oxygen species (ROS), the chemokine monocyte chemoattractant protein-1 (MCP-1), NAD(P)H oxidase activity, mRNA expression of NOX-2 and NOX-4, and lower PVN IL-10, and higher plasma levels of PICs and NE, and lower plasma IL-10. PVN infusion of NF-κB inhibitor PDTC attenuated all these changes. These findings suggest that NF-κB activation in the PVN increases sympathoexcitation and hypertensive response, which are associated with the increases of PICs and oxidative stress in the PVN; PVN inhibition of NF-κB activity attenuates PICs and oxidative stress in the PVN, thereby attenuates hypertension and cardiac hypertrophy. - Highlights: • Spontaneously hypertensive rats exhibit neurohormonal excitation in the PVN. • PVN inhibition of NF-κB attenuates hypertension-induced cardiac hypertrophy. • PVN inhibition of NF-κB attenuates hypertension-induced neurohormonal excitation. • PVN inhibition of NF-κB attenuates hypertension-induced imbalance of cytokines

Histamine Induces Bovine Rumen Epithelial Cell Inflammatory Response via NF-κB Pathway.

Science.gov (United States)

Sun, Xudong; Yuan, Xue; Chen, Liang; Wang, Tingting; Wang, Zhe; Sun, Guoquan; Li, Xiaobing; Li, Xinwei; Liu, Guowen

2017-01-01

Subacute ruminal acidosis (SARA) is a common disease in high-producing lactating cows. Rumenitis is the initial insult of SARA and is associated with the high concentrations of histamine produced in the rumen of dairy cows during SARA. However, the exact mechanism remains unclear. The objective of the current study is to investigate whether histamine induces inflammation of rumen epithelial cells and the underlying mechanism of this process. Bovine rumen epithelial cells were cultured and treated with different concentrations of histamine and pyrrolidine dithiocarbamate (PDTC, an NF-κB inhibitor) cultured in different pH medium (pH 7.2 or 5.5). qRT-PCR, Western-blotting, ELISA and immunocytofluorescence were used to evaluate whether histamine activated the NF-κB pathway and inflammatory cytokines. The results showed that histamine significantly increased the activity of IKK β and the phosphorylation levels of IκB α, as well as upregulated the mRNA and protein expression levels of NF-κB p65 in the rumen epithelial cells cultured in neutral (pH=7.2) and acidic (pH=5.5) medium. Furthermore, histamine treatment also significantly increased the transcriptional activity of NF-κB p65. High expression and transcriptional activity of NF-κB p65 significantly increased the mRNA expressions and concentrations of inflammatory cytokines, tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and interleukin 1 beta (IL-1β), thereby inducing the inflammatory response in bovine rumen epithelial cells. However, inhibition of NF-κB p65 by PDTC significantly decreased the expressions and concentrations of the inflammatory cytokines induced by histamine in the rumen epithelial cells cultured in the neutral and acidic medium. The present data indicate that histamine induces the inflammatory response of bovine rumen epithelial cells through the NF-κB pathway. © 2017 The Author(s). Published by S. Karger AG, Basel.

Polymeric metal chelates with piperazine(bis)dithiocarbamate

International Nuclear Information System (INIS)

Larionov, S.V.; Kosareva, L.A.; Ikorskij, V.N.; Uskov, E.M.

1982-01-01

Roentgenoamorphous polymer chelates of Fe 3 , Co 2 , Ni 2 , Cu 2 , Zn 2 , Cd 2 , Pb 2 with tetradentate bridge ligand piperazine-(bis) dithiocarbamate have been synthesized. IR spectra in the region 200-400 cm - 1 point to coordination of sulphur atoms of groups CS 2- with metals. It is found that among the polymers synthesized CuLxH 2 O possesses the lowest electric resistance

Radiolabeling and biodistribution of 62Cu-dithiocarbamate

International Nuclear Information System (INIS)

Matsumoto, Kazuya; Fujibayashi, Yasuhisa; Yokoyama, Akira; Konishi, Junji.

1990-01-01

The newly developed 62 Zn/ 62 Cu generator system has made available the production of the short-lived 62 Cu (T 1/2 = 9.8 min) positron radionuclide, eluted as 62 Cu-glycine. In the search for 62 Cu labeled radiopharmaceuticals for positron CT (PET) brain diagnostic studies, two ligands N,N-diethyl- and N,N-dimethyl-dithiocarbamic acid (DDC and DmDC) were selected, based on their Cu chelating abilities and the neutral lipophilic character of their copper chelates. In the present work, an in vitro study with non-radioactive Cu-glycine showed that both ligands easily formed the stable, neutral Cu-DDC and Cu-DmDC chelates (1:2 metal-ligand complexes) based on the ligand exchange reaction. Then the 62 Zn/ 62 Cu generator eluate, the 62 Cu-glycine was used for the radiolabeling of DDC and DmDC. The following HPLC analysis revealed that the ligand exchange reaction proceeded rapidly; the radiochemical purities of 62 Cu-DDC and 62 Cu-DmDC were extremely high (non-detectable 62 Cu-glycine) and both chelates were more lipophilic than 62 Cu-glycine. The mouse biodistribution of both radiolabeled compounds, 62 Cu-DDC and 62 Cu-DmDC indicated a brain accumlation of 2.8 and 5.3 times higher than 62 Cu-glycine, 15 min post injection, respectively. The brain accumulation observed with both 62 Cu-DDC and 62 Cu-DmDC might be due to their stable, neutral and lipophilic character; the latter enhanced by the presence of the methylated side chains. The gathered results indicated the applicability of dithiocarbamic acid derivatives in the production of new 62 Cu-labeled compounds using the 62 Zn/ 62 Cu generator system based on the ligand exchange reaction with 62 Cu-glycine eluate. Further studies with Cu-dithiocarbamic acid derivatives for development of new generator-produced 62 Cu positron radiopharmaceuticals can be recalled. (author)

Pyrrolidine nucleotide analogs with a tunable conformation

Czech Academy of Sciences Publication Activity Database

Poštová Slavětínská, Lenka; Rejman, Dominik; Pohl, Radek

2014-01-01

Roč. 10, Aug 22 (2014), s. 1967-1980 ISSN 1860-5397 R&D Projects: GA ČR GA13-24880S Institutional support: RVO:61388963 Keywords : conformation * NMR * nucleic acids * nucleotide analog * phosphonic acid * pseudorotation * pyrrolidine Subject RIV: CC - Organic Chemistry Impact factor: 2.762, year: 2014 http://www.beilstein-journals.org/bjoc/single/articleFullText.htm?publicId=1860-5397-10-205

Hindered Csbnd N bond rotation in triazinyl dithiocarbamates

Science.gov (United States)

Jung, Taesub; Do, Hee-Jin; Son, Jongwoo; Song, Jae Hee; Cha, Wansik; Kim, Yeong-Joon; Lee, Kyung-Koo; Kwak, Kyungwon

2018-01-01

The substituent and solvent effects on the rotation around a Csbnd N amide bond were studied for a series of triazine dibenzylcarbamodithioates. The Gibbs free energies (ΔG‡) were measured to be 16-18 kcal/mol in DMSO-d6 and toluene-d8 using variable-temperature nuclear magnetic resonance (VT-1H NMR) spectroscopy. Density functional theory (DFT) calculations reproduced the experimental observations with various substituents, as well as solvents. From the detailed analysis of the DFT results, we found that the electron donating dibenzyl amine group increased the electron population on the triazinyl ring, which decreased the rotational barrier of the Csbnd N bond in the dithiocarbamate group attached to the triazinyl ring. The higher electron population on the triazine moiety stabilizes the partial double bond character of the Ssbnd C bond, which competitively excludes the double bond character of the Csbnd N bond. Therefore, the rotational dynamics of the Csbnd N bond in dithiocarbamates can be a sensitive probe to small differences in the electron population of substituents on sulfur.

Isosteric phosphonate pyrrolidine-based dinucleoside monophosphate analogues

Czech Academy of Sciences Publication Activity Database

Vaněk, Václav; Buděšínský, Miloš; Kavenová, Ivana; Rinnová, Markéta; Rosenberg, Ivan

2003-01-01

Roč. 22, 5/8 (2003), s. 1065-1067 ISSN 1525-7770. [International Roundtable Nucleosides, Nucleotides and Nucleic Acids /15./. Leuven, 10.09.2002-14.09.2002] R&D Projects: GA ČR GA203/01/1166; GA AV ČR IAA4055101 Institutional research plan: CEZ:AV0Z4055905 Keywords : pyrrolidine-based phosphonate nucleotides * ApA analogues * triplex Subject RIV: CC - Organic Chemistry Impact factor: 0.813, year: 2003

[Gallic acid inhibits inflammatory response of RAW264.7 macrophages by blocking the activation of TLR4/NF-κB induced by LPS].

Science.gov (United States)

Huang, Lihua; Hou, Lin; Xue, Hainan; Wang, Chunjie

2016-12-01

Objective To observe the influence of gallic acid on Toll-like receptor 4/nuclear factor-κB (TLR4/NF-κB) pathway in the RAW264.7 macrophages stimulated by lipopolysaccharide (LPS). Methods RAW264.7 macrophages were divided into the following groups: control group, LPS group, LPS combined with gallic acid group, LPS combined with pyrrolidine dithiocarbamate (PDTC) group and LPS combined with dexamethasone (DM) group. RAW264.7 cells were cultured for 24 hours after corresponding treatments. The levels of tumor necrosis factor α (TNF-α), interleukin-1 (IL-1) and IL-6 were detected by ELISA. The levels of TLR4 and NF-κB mRNAs were tested by real-time PCR. The levels of p-IκBα, p65, p-p65 and TLR4 proteins were examined by Western blotting. Results The expression levels of TNF-α, IL-1 and IL-6 were up-regulated in the RAW264.7 macrophages after stimulated by LPS. Gallic acid could reduce the elevated expression levels of TNF-α, IL-1 and IL-6 induced by LPS. The expression of TLR4 significantly increased after stimulated by LPS and NF-κB was activated. Gallic acid could reverse the above changes and prevent the activation of NF-κB. Conclusion Gallic acid could inhibit LPS-induced inflammatory response in RAW264.7 macrophages via TLR4/NF-κB pathway.

Effects of substituted dithiocarbamates on distribution and excretion of inorganic mercury in mice

International Nuclear Information System (INIS)

Gale, G.R.; Atkins, L.M.; Smith, A.B.; Jones, M.M.

1985-01-01

Diethyldithiocarbamate (DDTC) and six of its N,N-disubstituted congeners were evaluated for their relative efficacies in mobilizing and promoting excretion of mercury (Hg ++ ) using mice which had been given 203 Hg ++ ; D-penicillamine (PEN) was used as a positive control compound. While none was as effective as PEN when compared on a molar dose basis, significant activity as assessed by reduction of whole body 203 Hg burden, was observed following treatment with three of the analogs. The order of effectiveness was PEN greater than N-methyl-N-dithiocarboxyglucamine (MDCG) greater than di(carboxymethyl)dithiocarbamate (DCDC) greater than di(hydroxyethyl)dithiocarbamate (DHDC)

Low-energy electron-induced dissociation in gas-phase nicotine, pyridine, and methyl-pyrrolidine

Science.gov (United States)

Ryszka, Michal; Alizadeh, Elahe; Li, Zhou; Ptasińska, Sylwia

2017-09-01

Dissociative electron attachment to nicotine, pyridine, and N-methyl-pyrrolidine was studied in the gas phase in order to assess their stability with respect to low-energy electron interactions. Anion yield curves for different products at electron energies ranging from zero to 15 eV were measured, and the molecular fragmentation pathways were proposed. Nicotine does not form a stable parent anion or a dehydrogenated anion, contrary to other biological systems. However, we have observed complex dissociation pathways involving fragmentation at the pyrrolidine side accompanied by isomerization mechanisms. Combining structure optimization and enthalpy calculations, performed with the Gaussian09 package, with the comparison with a deuterium-labeled N-methyl-d3-pyrrolidine allowed for the determination of the fragmentation pathways. In contrast to nicotine and N-methylpyrrolidine, the dominant pathway in dissociative electron attachment to pyridine is the loss of hydrogen, leading to the formation of an [M—H]- anion. The presented results provide important new information about the stability of nicotine and its constituent parts and contribute to a better understanding of the fragmentation mechanisms and their effects on the biological environment.

New mono-organotin (IV) dithiocarbamate complexes

Energy Technology Data Exchange (ETDEWEB)

Muthalib, Amirah Faizah Abdul; Baba, Ibrahim [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi (Malaysia)

2014-09-03

Eighteen new mono-organotin dithiocarbamate compounds derived each nine from methyltin(IV) and phenyltin(IV) reacted using in-situ method with various type of N-dialkylamine together with carbon disulphide with the ratio of 1:3:3. Elemental and gravimetric analysis showed that the general formula of these compounds were RSnCl[S{sub 2}CNR′R″]{sub 2} (R= Ph, CH{sub 3}, R′ = CH{sub 3}, C{sub 2}H{sub 5}, C{sub 7}H{sub 7} and R″ = C{sub 2}H{sub 5}, C{sub 6}H{sub 11}, iC{sub 3}H{sub 7}, C{sub 7}H{sub 7}). These compounds had been characterized by infrared spectroscopy, ultraviolet spectroscopy, {sup 1}H, {sup 13}C NMR spectroscopy and single crystal X-ray crystallography. The infrared spectra of these compounds showed three important peaks indicating the formation of dithiocarbamate compounds, ν(CN), ν(CS) and ν(Sn-S) band which present in the region of 1444–1519, 954–1098 and 318–349 cm{sup −1} respectively. The ultraviolet-visible spectra showed an absorption band for the π - π* transition of NCS group in the range of 253 – 259 nm due to the intramolecular charge transfer of the ligand. The {sup 13}C NMR spectra showed an important shift for δ(N{sup 13}CS{sub 2}) in the range of 196.8 – 201.9 ppm.. Single crystal X-ray diffraction studies showed three new structures with the general formula of PhSnCl[S{sub 2}CN(Et)(i−Pr)]{sub 2}, MeSnCl[S{sub 2}CN(Me)(Cy)]{sub 2} and MeSnCl[S{sub 2}CN(i−Pr)(CH{sub 2}Ph)]{sub 2}. All structures having a distorted octahedral geometry set by CClS{sub 4} donor atom from the two

In situ XAS of the solvothermal decomposition of dithiocarbamate complexes

NARCIS (Netherlands)

Islam, H.-U.; Roffey, A.; Hollingsworth, N.; Catlow, R.; Wolthers, M.; de Leeuw, N.H.; Bras, W.; Sankar, G.; Hogarth, G.

2012-01-01

An in situ XAS study of the solvothermal decomposition of iron and nickel dithiocarbamate complexes was performed in order to gain understanding of the decomposition mechanisms. This work has given insight into the steps involved in the decomposition, showing variation in reaction pathways between

Pyrrolidine constrained bipyridyl-dansyl click fluoroionophore as selective Al(3+)sensor.

Science.gov (United States)

Maity, Debabrata; Govindaraju, T

2010-07-07

A pyrrolidine constrained bipyridyl-dansyl (ionophore-fluorophore) conjugate with triazole linker was synthesised through click chemistry. The fluoroionophore serves as a selective ratiometric and colorimetric chemosensor for Al(3+) based on internal charge transfer (ICT).

Dual platinum and pyrrolidine catalysis in the direct alkylation of allylic alcohols: selective synthesis of monoallylation products.

Science.gov (United States)

Shibuya, Ryozo; Lin, Lu; Nakahara, Yasuhito; Mashima, Kazushi; Ohshima, Takashi

2014-04-22

A dual platinum- and pyrrolidine-catalyzed direct allylic alkylation of allylic alcohols with various active methylene compounds to produce products with high monoallylation selectivity was developed. The use of pyrrolidine and acetic acid was essential, not only for preventing undesirable side reactions, but also for obtaining high monoallylation selectivity. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A rapid screening method for heavy metals in biological materials by emission spectroscopy.

Science.gov (United States)

Blacklock, E C; Sadler, P A

1981-06-02

A semi-quantitative screening method for heavy metals in biological material is described. The metals are complexed with ammonium pyrrolidine dithiocarbamate, sodium diethyl dithiocarbamate and potassium sodium tartrate. The solutions are adjusted to pH 4 and then extracted into chloroform. The chloroform phase is evaporated onto a matrix mixture of lithium fluoride and graphite. The sample is analysed by direct current arc emission spectroscopy using a 3 metre grating spectrograph. The spectra are recorded on a photographic plate. The method is developed on aqueous and spiked samples and then applied to in vivo samples containing toxic levels of heavy metals. Atomic absorption spectroscopy is used to check standard concentrations and to monitor the efficiency of the extraction procedure.

Synthesis of (E-2,4-Dinitro-N-((2E,4E-4-phenyl-5-(pyrrolidin-1-ylpenta-2,4-dienylideneaniline

Directory of Open Access Journals (Sweden)

Mostafa Fesanghari

2009-07-01

Full Text Available (E-2,4-Dinitro-N-((2E,4E-4-phenyl-5-(pyrrolidin-1-ylpenta-2,4-dienylidene aniline dye was prepared in one pot by reaction of premade N-2,4-dinitrophenyl-3-phenylpyridinium chloride (DNPPC and pyrrolidine in absolute MeOH.

Zeolite synthesis from the pyrrolidine containing system and their catalytic properties in the methanol conversion reaction

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Kunio; Kiyozumi, Yoshimichi; Shin, Shigemitsu; Ogawa, Kiyoshi; Yamazaki, Yasuyoshi; Watanabe, Hideo

1987-12-18

Systhesis of zeolite from a system containing cheaper pyrrolidine as a crystallization regulator than quaternary ammonium ion was carried out and the methanol conversion reaction was studied over the systhesized zeolite to get C/sub 2/ and C/sub 3/ olefins. Hydrous gels were prepared by adding and agitating pyrrolidine, water glass and sulfuric acid to aluminum sulfate solution; and aluminum nitrate, colloidal silica and pyrrolidine to NaOH solution. Five zeolite, that is, ZSM-5, ZSM-35, ZSM-39, ZSM-48 and KZ-1 were synthesized by changing gel components. X-ray powder diffraction, BET specific surface areas, micropore diameters, micropore volumes, oxygen contents by scanning electron photomicrographs and infra-red spectra were examined. The organic base in hydrous gels influenced greatly on the zeolite composition and structure. The ZSM-5 zeolite exhibited the superior performance as to a high selectivity of light olefins over the target of development. (12 figs, 1 tab, 20 refs)

Resveratrol Protects against TNF-α-Induced Injury in Human Umbilical Endothelial Cells through Promoting Sirtuin-1-Induced Repression of NF-KB and p38 MAPK

Science.gov (United States)

Huang, Shujie; Zhu, Pengli

2016-01-01

Inflammation and reactive oxygen species (ROS) play important roles in the pathogenesis of atherosclerosis. Resveratrol has been shown to possess anti-inflammatory and antioxidative stress activities, but the underlying mechanisms are not fully understood. In the present study, we investigated the molecular basis associated with the protective effects of resveratrol on tumor necrosis factor-alpha (TNF-α)-induced injury in human umbilical endothelial cells (HUVECs) using a variety of approaches including a cell viability assay, reverse transcription and quantitative polymerase chain reaction, western blot, and immunofluorescence staining. We showed that TNF-α induced CD40 expression and ROS production in cultured HUVECs, which were attenuated by resveratrol treatment. Also, resveratrol increased the expression of sirtuin 1 (SIRT1); and repression of SIRT1 by small-interfering RNA (siRNA) and the SIRT1 inhibitor Ex527 reduced the inhibitory effects of resveratrol on CD40 expression and ROS generation. In addition, resveratrol downregulated the levels of p65 and phospho-p38 MAPK, but this inhibitory effect was attenuated by the suppression of SIRT1 activity. Moreover, the p38 MAPK inhibitor SD203580 and the nuclear factor (NF)-κB inhibitor pyrrolidine dithiocarbamate (PDTC) achieved similar repressive effects as resveratrol on TNF-α-induced ROS generation and CD40 expression. Thus, our study provides a mechanistic link between resveratrol and the activation of SIRT1, the latter of which is involved in resveratrol-mediated repression of the p38 MAPK/NF-κB pathway and ROS production in TNF-α-treated HUVECs. PMID:26799794

Pyrrolidin-2-one derivatives may reduce body weight in rats with diet-induced obesity.

Science.gov (United States)

Dudek, Magdalena; Knutelska, Joanna; Bednarski, Marek; Nowiński, Leszek; Zygmunt, Małgorzata; Kazek, Grzegorz; Mordyl, Barbara; Głuch-Lutwin, Monika; Zaręba, Paula; Kulig, Katarzyna; Sapa, Jacek

2016-04-05

Obesity affects an increasing number of individuals in the human population and significant importance is attached to research leading to the discovery of drug which would effectively reduce weight. The search for new drugs with anorectic activity and acting within the adrenergic system has attracted the interest of researchers. This study concerns the experimental effects on body weight of α2-adrenoceptor antagonists from the group of pyrrolidin-2-one derivatives in rats with diet-induced obesity. The intrinsic activity of the test compounds at the α-adrenoreceptors was tested. Obesity in rats was obtained by the use of fatty diet and then the influence of the test compounds on body weight, food and water intakes, lipid and glucose profiles and glycerol and cortisol levels were determinated. The effects of the compounds on locomotor activity, body temperature, blood pressure and heart rate were tested. One of the test compounds (1-(3-(4-phenylpiperazin-1-yl)propyl)pyrrolidin-2-one) reduces the animal's body weight and the amount of peritoneal adipose tissue during chronic administration, at the same time it does not cause significant adverse effects on the cardiovascular system. This compound decreases temperature and elevates glycerol levels and does not change the locomotor activity and cortisol level at anti-obese dose. Some derivatives of pyrrolidin-2-one that act as antagonists of the α2-adrenoreceptor may reduce body weight. Reducing body weight for 1-(3-(4-phenylpiperazin-1-yl)propyl)pyrrolidin-2-one can be associated with decrease in food intake, body fat reduction, reduction of blood glucose, and increased thermogenesis and lipolysis. This effect cannot be the result of changes in spontaneous activity or stress. Copyright © 2016 Elsevier B.V. All rights reserved.

One pot synthesis of 2-hydroxy pyrrolidine derivatives

Directory of Open Access Journals (Sweden)

Putta. P. Varma

2011-01-01

Full Text Available One pot reaction of various 2-amino-thiadiazoles or thiazoles and 2,3- dihydrofuran under mild condition in presence of CeCl 3.7H 2O as catalyst transformed the amino group of 2-amino-thiadiazoles or thiazoles into a medicinally important 2-hydroxy pyrrolidine ring system in good to excellent yields. The generality of the reaction was sufficiently investigated and demonstrated. The new reaction path way for this conversion was established by spectroscopic and analytical methods.

Feasible Management of Southern Corn Leaf Blight via Induction of Systemic Resistance by Bacillus cereus C1L in Combination with Reduced Use of Dithiocarbamate Fungicides

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Yi-Ru Lai

2016-10-01

Full Text Available Dithiocarbamate fungicides such as maneb and mancozeb are widely used nonsystemic protectant fungicides to control various plant fungal diseases. Dithiocarbamate fungicides should be frequently applied to achieve optimal efficacy of disease control and avoid either decline in effectiveness or wash-off from leaf surface. Dithiocarbamates are of low resistance risk but have the potential to cause human neurological diseases. The objective of this study was to develop a strategy to effectively control plant disease with reduced use of dithiocarbamtes. Southern corn leaf blight was the model pathosystem for the investigation. When corn plants were drench-treated with Bacillus cereus C1L, a rhizobacterium able to induce systemic resistance in corn plants against southern leaf blight, frequency of spraying dithiocarbamate fungicides could be decreased. The treatment of B. cereus C1L was able to protect maize from southern leaf blight while residues of dithiocarbamates on leaf surface were too low to provide sufficient protection. On the other hand, frequent sprays of mancozeb slightly but significantly reduced growth of corn plants under natural conditions. In contrast, application of B. cereus C1L can significantly promote growth of corn plants whether sprayed with mancozeb or not. Our results provide the information that plant disease can be well controlled by rhizobacteria-mediated induced systemic resistance in combination with reduced but appropriate application of dithiocarbamate fungicides just before a heavy infection period. An appropriate use of rhizobacteria can enhance plant growth and help plants overcome negative effects caused by dithiocarbamates.

Dithiocarbamates are teratogenic to developing zebrafish through inhibition of lysyl oxidase activity

NARCIS (Netherlands)

van Boxtel, A.L.; Kamstra, J.H.; Fluitsma, D.M.; Legler, J.

2010-01-01

Dithiocarbamates (DTCs) are a class of compounds that are extensively used in agriculture as pesticides. As such, humans and wildlife are undoubtedly exposed to these chemicals. Although DTCs are thought to be relatively safe due to their short half lives, it is well established that they are

Synthesis, structural characterization, and thermal stability studies of heteroleptic cadmium(II) dithiocarbamate with different pyridyl groups

Science.gov (United States)

Onwudiwe, Damian C.; Hosten, Eric C.

2018-01-01

The synthesis, characterization and crystal structures of three chloroform solvated adducts of cadmium with mixed ligands of N-alkyl-N-phenyldithiocarbamate and pyridine, 2,2-bipyridine and 1, 10 phenanthroline represented as [CdL1L2 (py)2]·CHCl3(1), [CdL1L2bpy]•CHCl3(2), and [CdL1L2phen]•CHCl3(3) (LI = N-methyl-N-phenyldithiocarbamate, L2 = N-ethyl-N-phenyldithiocarbamate, py = pyridine, bpy = 2,2-bipyridine and phen = 1,10-phenanthroline) respectively are reported. Complex 1, which crystallized in the monoclinic space group P-1, is a centrosymmetric dimeric structure where each Cd center is bonded to two monodentate pyridine, a bidentate terminal dithiocarbamate, and another bidentate bridging dithiocarbamate to form a four-membered ring. Complex 2 crystallized in the monoclinic space group P21/c, with four discrete monomeric molecules in the asymmetric unit. The structure presents a cadmium atom coordinated by two sulphur atoms of a dithiocarbamate ligand and two nitrogen atoms of the 2,2‧-bipyridine to form a CdS4N2 fragment, thus giving the structure around the Cd atom a distorted trigonal prism geometry. Complex 3 contains two discrete monomeric molecules of (phenanthroline) (N, N-methyl phenyl-N, N-ethyl phenyl dithiocarbamato)cadmium (II) per unit cell, and the complex crystallized in the triclinic space group P-1. The structure showed that the Cd atom is bonded to two bidentate dithiocarbamate ligands and to one bidentate phenanthroline ligand in a distorted trigonal prism geometry. All the compounds resulted in CdS as residue upon thermal decomposition process conducted under inert atmosphere.

Crystal structure of 1-{4-hydroxy-3-[(pyrrolidin-1-ylmethyl]phenyl}-3-phenylprop-2-en-1-one

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Abdullah Aydın

2016-05-01

Full Text Available In the title compound, C20H21NO2, the pyrrolidine ring adopts an envelope conformation with the N atom at the flap position. The central benzene ring makes dihedral angles of 21.39 (10 and 80.10 (15° with the phenyl ring and the mean plane of the pyrrolidine ring, respectively. The molecular conformation is stabilized by an intramolecular O—H...N hydrogen bond, which closes an S(6 ring. A weak C—H...π interaction is observed in the crystal.

Synthesis, Structure, Characterization, and Decomposition of Nickel Dithiocarbamates: Effect of Precursor Structure and Processing Conditions on Solid-State Products

Science.gov (United States)

Hepp, Aloysius F.; Kulis, Michael J.; McNatt, Jeremiah S.; Duffy, Norman V.; Hoops, Michael D.; Gorse, Elizabeth; Fanwick, Philip E.; Masnovi, John; Cowen, Jonathan E.; Dominey, Raymond N.

2016-01-01

Single-crystal X-ray structures of four nickel dithiocarbamate complexes, the homoleptic mixed-organic bis-dithiocarbamates Ni[S2CN(isopropyl)(benzyl)]2, Ni[S2CN(ethyl)(n-butyl)]2, and Ni[S2CN(phenyl)(benzyl)]2, as well as the heteroleptic mixed-ligand complex NiCl[P(phenyl)3][(S2CN(phenyl)(benzyl)], were determined. Synthetic, spectroscopic, structural, thermal, and sulfide materials studies are discussed in light of prior literature. The spectroscopic results are routine. A slightly distorted square-planar nickel coordination environment was observed for all four complexes. The organic residues adopt conformations to minimize steric interactions. Steric effects also may determine puckering, if any, about the nickel and nitrogen atoms, both of which are planar or nearly so. A trans-influence affects the Ni-S bond distances. Nitrogen atoms interact with the CS2 carbons with a bond order of about 1.5, and the other substituents on nitrogen display transoid conformations. There are no strong intermolecular interactions, consistent with prior observations of the volatility of nickel dithiocarbamate complexes. Thermogravimetric analysis of the homoleptic species under inert atmosphere is consistent with production of 1:1 nickel sulfide phases. Thermolysis of nickel dithiocarbamates under flowing nitrogen produced hexagonal or -NiS as the major phase; thermolysis under flowing forming gas produced millerite (-NiS) at 300 C, godlevskite (Ni9S8) at 325 and 350 C, and heazlewoodite (Ni3S2) at 400 and 450 C. Failure to exclude oxygen results in production of nickel oxide. Nickel sulfide phases produced seem to be primarily influenced by processing conditions, in agreement with prior literature. Nickel dithiocarbamate complexes demonstrate significant promise to serve as single-source precursors to nickel sulfides, a quite interesting family of materials with numerous potential applications.

Corn silk induced cyclooxygenase-2 in murine macrophages.

Science.gov (United States)

Kim, Kyung A; Shin, Hyun-Hee; Choi, Sang Kyu; Choi, Hye-Seon

2005-10-01

Stimulation of murine macrophages with corn silk induced cyclooxygenase (COX)-2 with secretion of PGE2. Expression of COX-2 was inhibited by pyrolidine dithiocarbamate (PDTC), and increased DNA binding by nuclear factor kappa B (NF-kappaB), indicating that COX-2 induction proceeds also via the NF-kappaB signaling pathway. A specific inhibitor of COX-2 decreased the expression level of inducible nitric oxide synthase (iNOS) stimulated by corn silk. PGE2 elevated the expression level of iNOS, probably via EP2 and EP4 receptors on the surface of the macrophages.

Spectroscopic and structural study of novel interaction product of pyrrolidine-2-thione with molecular iodine. Presumable mechanisms of oxidation

Science.gov (United States)

Chernov'yants, Margarita S.; Burykin, Igor V.; Starikova, Zoya A.; Tereznikov, Alexander Yu.; Kolesnikova, Tatiana S.

2013-09-01

Synthesis, spectroscopic and structural characterization of novel interaction product of pyrrolidine-2-thione with molecular iodine is reported. The ability of pyrrolidine-2-thione to form the outer-sphere charge-transfer complex C4H7NS·I2 with iodine molecule in dilute chloroform solution has been studied by UV/vis spectroscopy. Oxidative desulfurization promotes ring fusion of two pyrrolidine-2-thione molecules. The product of iodine induced oxidative desulfurization has been studied by X-ray diffraction method. The crystal structure of the reaction product is formed by 5-(2-thioxopyrrolidine-1-yl)-3,4-dihydro-2H-pyrrolium (C8H13N2S+) cations and pentaiodide anions I5-, which are linked by the intermolecular I⋯Hsbnd C and I⋯C close contacts. The angular pentaiodide anions can be considered as structures formed by coordination of two iodine molecules to the iodide ion (type 1) or by the coordination of iodine molecule to the triiodide ion (type 2).

N-(3-aminopropyl)pyrrolidin-2-one, a product of spermidine catabolism in vivo.

Science.gov (United States)

Seiler, N; Knödgen, B; Haegele, K

1982-01-01

A high-pressure-liquid-chromatographic method suitable for the separation and sensitive detection of putreanine and isoputreanine is described. This method allowed us to study the formation of the metabolites of the oxidative deamination of spermidine and N1-acetylspermidine. Administration of spermidine trishydrochloride to mice causes a time-dependent accumulation of putreanine and N-(3-aminopropyl)pyrrolidin-2-one in various organs. The latter compound yields isoputreanine by hydrolysis. It can be assumed that the analogous lactam. N-(3-acetamidopropyl)pyrrolidin-2-one is formed from N1-acetylspermidine, since hydrolysis of tissue extracts of N1-acetylspermidine-treated mice produced isoputreanine. No putreanine is formed under these conditions. Pretreatment of the animals with 25 mg of aminoguanidine sulphate/kg body wt. completely inhibits the formation of putreanine and of the respective isoputreanine precursor from spermidine and N1-acetylspermidine. This suggests a role for a diamine oxidase-like enzyme in the oxidative deamination of spermidine and N1-acetylspermidine. Images Fig. 6. PMID:7159392

Determination of trace amounts of selenium in minerals and rocks by flame less atomic-absorption spectrometry

International Nuclear Information System (INIS)

Alduan, F. A.; Capdevilla, C.

1980-01-01

The determination of trace amounts of selenium In silicate rocks and feldspar by solvent extraction and graphite furnace atomic-absorption spectrometry has been stu- died. Sodium diethyl-ditio carbamate and ammonium pyrrolidine dithiocarbamate have been tried as chelating agents. The best results are achieved when selenium is extracted Into carbon tetrachloride as the sodium diethyldithiocarbamate complex. The method allows to detect 0,75 ppm of selenium in the sample. Recoveries are about 100%. (Author) 7 refs

Determination of trace amounts of selenium in minerals and rocks by flame less atomic-absorption spectrometry; Determinacion de selinio en minerales y rocas por espectrometria de absorcion atomica

Energy Technology Data Exchange (ETDEWEB)

Alduan, F. A.; Capdevilla, C.

1980-07-01

The determination of trace amounts of selenium In silicate rocks and feldspar by solvent extraction and graphite furnace atomic-absorption spectrometry has been stu- died. Sodium diethyl-ditio carbamate and ammonium pyrrolidine dithiocarbamate have been tried as chelating agents. The best results are achieved when selenium is extracted Into carbon tetrachloride as the sodium diethyldithiocarbamate complex. The method allows to detect 0,75 ppm of selenium in the sample. Recoveries are about 100%. (Author) 7 refs.

Activation of AMPA receptor promotes TNF-α release via the ROS-cSrc-NFκB signaling cascade in RAW264.7 macrophages

Energy Technology Data Exchange (ETDEWEB)

Cheng, Xiu-Li [Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China); Ding, Fan [Office of Scientific R& D, Tsinghua University, Beijing (China); Li, Hui; Tan, Xiao-Qiu [Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China); Liu, Xiao [Department of Pathophysiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China); Cao, Ji-Min, E-mail: caojimin@126.com [Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China); Gao, Xue, E-mail: longlongnose@163.com [Department of Pathophysiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China)

2015-05-29

The relationship between glutamate signaling and inflammation has not been well defined. This study aimed to investigate the role of AMPA receptor (AMPAR) in the expression and release of tumor necrosis factor-alpha (TNF-α) from macrophages and the underlying mechanisms. A series of approaches, including confocal microscopy, immunofluorescency, flow cytometry, ELISA and Western blotting, were used to estimate the expression of AMPAR and downstream signaling molecules, TNF-α release and reactive oxygen species (ROS) generation in the macrophage-like RAW264.7 cells. The results demonstrated that AMPAR was expressed in RAW264.7 cells. AMPA significantly enhanced TNF-α release from RAW264.7 cells, and this effect was abolished by CNQX (AMPAR antagonist). AMPA also induced elevation of ROS production, phosphorylation of c-Src and activation of nuclear factor (NF)-κB in RAW264.7 cells. Blocking c-Src by PP2, scavenging ROS by glutathione (GSH) or inhibiting NF-κB activation by pyrrolidine dithiocarbamate (PDTC) decreased TNF-α production from RAW264.7 cells. We concluded that AMPA promotes TNF-α release in RAW264.7 macrophages likely through the following signaling cascade: AMPAR activation → ROS generation → c-Src phosphorylation → NF-κB activation → TNF-α elevation. The study suggests that AMPAR may participate in macrophage activation and inflammation. - Highlights: • AMPAR is expressed in RAW264.7 macrophages and is upregulated by AMPA stimulation. • Activation of AMPAR stimulates TNF-α release in macrophages through the ROS-cSrc-NFκB signaling cascade. • Macrophage AMPAR signaling may play an important role in inflammation.

[Effects of hypoxia on the phenotype transformation of human dermal fibroblasts to myofibroblasts and the mechanism].

Science.gov (United States)

Zhao, B; Han, F; Zhang, W; Wang, X J; Zhang, J; Yang, F F; Shi, J H; Su, L L; Hu, D H

2017-06-20

Objective: To investigate the effects of hypoxia on the phenotype transformation of human dermal fibroblasts to myofibroblasts and the mechanism. Methods: The third passage of healthy adult human dermal fibroblasts in logarithmic phase were cultured in DMEM medium containing 10% fetal bovine serum for the following five experiments. (1) In experiments 1, 2, and 3, cells were divided into normoxia group and hypoxia group according to the random number table, with 10 dishes in each group. Cells of normoxia group were cultured in incubator containing 21% oxygen, while those of hypoxia group with 1% oxygen. At post culture hour (PCH) 0 and 48, 5 dishes of cells were collected from each group, respectively. mRNA expressions of markers of myofibroblasts including alpha smooth muscle actin (α-SMA), type Ⅰ collagen, and type Ⅲ collagen of cells were determined with real time fluorescent quantitative reverse transcription polymerase chain reaction in experiment 1. Protein expressions of α-SMA, type Ⅰ collagen, and type Ⅲ collagen of cells were determined with Western blotting in experiment 2. The protein expression of nuclear factor-kappa B (NF-κB) of cells was determined with Western blotting in experiment 3. (2) In experiment 4, cells were divided into normoxia group, hypoxia group, and hypoxia+ pyrrolidine dithiocarbamate (PDTC) group according to the random number table, with 5 dishes in each group. Cells in the former two groups were treated the same as those in experiment 1. Cells in hypoxia+ PDTC group were treated the same as those in hypoxia group plus adding 4 mL PDTC with a final molarity of 10 μmol/L in the culture medium. At PCH 48, the protein expression of NF-κB of cells was determined with Western blotting. (3) In experiment 5, cells were divided into normoxia group, hypoxia group, hypoxia+ PDTC group, and normoxia+ PDTC group according to the random number table, with 5 dishes in each group. Cells in the former three groups were treated the

Spiro[pyrrolidine-3,3′-oxindoles] and Their Indoline Analogues as New 5-HT6 Receptor Chemotypes

Directory of Open Access Journals (Sweden)

Ádám A. Kelemen

2017-12-01

Full Text Available Synthetic derivatives of spiro[pyrrolidinyl-3,3′-oxindole] alkaloids (coerulescine analogues were investigated as new ligands for aminergic G-protein coupled receptors (GPCRs. The chemical starting point 2′-phenylspiro[indoline-3,3′-pyrrolidin]-2-one scaffold was identified by virtual fragment screening utilizing ligand- and structure based methods. As a part of the hit-to-lead optimization a structure-activity relationship analysis was performed to explore the differently substituted 2′-phenyl-derivatives, introducing the phenylsulphonyl pharmacophore and examining the corresponding reduced spiro[pyrrolidine-3,3′-indoline] scaffold. The optimization process led to ligands with submicromolar affinities towards the 5-HT6 receptor that might serve as viable leads for further optimization.

Brightening and locking a weak and floppy N-H chromophore: the case of pyrrolidine.

Science.gov (United States)

Hesse, Susanne; Wassermann, Tobias N; Suhm, Martin A

2010-10-07

The N-H stretching signature of the puckering equilibrium between equatorial and axial pyrrolidine is analyzed via FTIR and Raman spectroscopy in supersonic jets as a function of aggregation. Vibrational temperatures along the expansion axis can be extracted from the Raman spectra and allow for a localization of the compression shock waves. While the equatorial conformation is more stable in the ground state monomer, this preference is probably switched in the excited state with one N-H stretching quantum. Furthermore, the dominant dimer involves an axial donor and the trimer and tetramer structures seem to prefer uniform axial conformations. The IR intensity is boosted by up to 3 orders of magnitude upon aggregation, whereas the Raman scattering intensity shows only moderate hydrogen bond effects. B3LYP and MP2 calculations provide a reasonable description of the N-H vibrational dynamics under the influence of self-aggregation. In mixed dimers with pyrrole, pyrrolidine assumes the role of a hydrogen bond acceptor.

Correction: Synthesis of pyrrolidine-3-carboxylic acid derivatives via asymmetric Michael addition reactions of carboxylate-substituted enones.

Science.gov (United States)

Yin, Feng; Garifullina, Ainash; Tanaka, Fujie

2018-04-25

Correction for 'Synthesis of pyrrolidine-3-carboxylic acid derivatives via asymmetric Michael addition reactions of carboxylate-substituted enones' by Feng Yin et al., Org. Biomol. Chem., 2017, 15, 6089-6092.

5-Chloro-5′′-[4-(dimethylaminobenzylidene]-4′-[4-(dimethylaminophenyl]-1′,1′′-dimethyldispiro[indoline-3,2′-pyrrolidine-3′,3′′-piperidine]-2,4′′-dione

Directory of Open Access Journals (Sweden)

I. S. Ahmed Farag

2014-01-01

Full Text Available The title compound, C34H38ClN5O2, has spiro links connecting the pyrrolidine ring and indole residue, as well as the piperidine and pyrrolidine rings. A half-chair conformation is found for the piperidine ring with the C atom connected to the spiro-C atom lying 0.738 (4 Å out of the plane of the remaining five atoms (r.m.s. deviation = 0.0407 Å. The methylene C atom is the flap in the envelope conformation for the pyrrolidine ring. In the crystal, supramolecular chains are sustained by alternating eight-membered {...HNCO}2 and 14-membered {...HC5O}2 synthons. Chains are connected into a three-dimensional network by (pyrrolidine-bound phenyl-methylC—H...π(pyrrolidine-bound phenyl edge-to-face interactions.

Validation of a GC-MS method for the estimation of dithiocarbamate fungicide residues and safety evaluation of mancozeb in fruits and vegetables.

Science.gov (United States)

Mujawar, Sumaiyya; Utture, Sagar C; Fonseca, Eddie; Matarrita, Jessie; Banerjee, Kaushik

2014-05-01

A sensitive and rugged residue analysis method was validated for the estimation of dithiocarbamate fungicides in a variety of fruit and vegetable matrices. The sample preparation method involved reaction of dithiocarbamates with Tin(II) chloride in aqueous HCl. The CS2 produced was absorbed into an isooctane layer and estimated by GC-MS selected ion monitoring. Limit of quantification (LOQ) was ⩽40μgkg(-1) for grape, green chilli, tomato, potato, brinjal, pineapple and chayote and the recoveries were within 75-104% (RSD<15% at LOQ). The method could be satisfactorily applied for analysis of real world samples. Dissipation of mancozeb, the most-used dithiocarbamate fungicide, in field followed first+first order kinetics with pre-harvest intervals of 2 and 4days in brinjal, 7 and 10days in grapes and 0day in chilli at single and double dose of agricultural applications. Cooking practices were effective for removal of mancozeb residues from vegetables. Copyright © 2013 Elsevier Ltd. All rights reserved.

Solvent extraction of some metal ions by dithiocarbamate types of chemically modified lipophilic chitosan

International Nuclear Information System (INIS)

Inoue, K.; Nakagawa, H.; Naganawa, H.; Tachimori, S.

2001-01-01

Chitosan is a basic polysaccharide containing primary amino groups with high reactivity. we prepared O,O'-decanoyl chitosan and dithiocarbamate O,O'-decanoyl chitosan; the former was soluble in chloroform and toluene, while latter was soluble not only these diluents but also in some aliphatic diluents such as hexane and kerosene which are employed in commercial scale solvent extraction. Solvent extraction by dithiocarbamate O,O'-decanoyl chitosan in kerosene was tested for some base metal ions from sulfuric acid solution. The sequence of selectivity for these metal ions was found to be as follows: Cu(II) >> Ni(II) > Cd(II) ∼ Fe(III) > Co(II) ∼ Zn(II). Copper(II) was quantitatively extracted at pH > 1 and quantitatively stripped with 2 M sulfuric acid solution. Solvent extraction of silver(I) and gold(III) from hydrochloric acid as well as lanthanides and americium(III) from nitrate solution were also tested. Americium was selectively extracted over trivalent lanthanides, suggesting a high possibility for the final treatment of high level radioactive wastes. (authors)

Facile access to unnatural dipeptide-alcohols based on cis-2,5-disubstituted pyrrolidines.

Science.gov (United States)

Jia, Yan-Yan; Li, Xiao-Ye; Wang, Ping-An; Wen, Ai-Dong

2015-02-11

Well-defined unnatural dipeptide-alcohols based on a cis-2,5-disubstitued pyrrolidine backbone were synthesized from commercially available starting materials meso-diethyl-2,5-dibromoadipate, (S)-(-)-1-phenylethylamine, and phenylalaninol. The structures of these unnatural dipeptide-alcohols are supported by HRMS, 1H- and 13C-NMR spectroscopy. These unnatural dipeptide-alcohols can act as building blocks for peptidomimetics.

Synthesis and biological evaluation of pyrrolidine derivatives as novel and potent sodium channel blockers for the treatment of ischemic stroke.

Science.gov (United States)

Seki, Maki; Tsuruta, Osamu; Tatsumi, Ryo; Soejima, Aki

2013-07-15

A novel series of pyrrolidine derivatives as Na(+) channel blockers was synthesized and evaluated for their inhibitory effects on neuronal Na(+) channels. Structure-activity relationship (SAR) studies of a pyrrolidine analogue 2 led to the discovery of 5e as a potent Na(+) channel blocker with a low inhibitory action against human ether-a-go-go-related gene (hERG) channels. Compound 5e showed remarkably neuroprotective activity in a rat transient middle cerebral artery occlusion (MCAO) model, suggesting that 5e would act as a neuroprotectant for ischemic stroke. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effective removal of coordinated copper from wastewater using a new dithiocarbamate-type supramolecular heavy metal precipitant.

Science.gov (United States)

Fu, Fenglian; Zeng, Haiyan; Cai, Qinhong; Qiu, Rongliang; Yu, Jimmy; Xiong, Ya

2007-11-01

A new dithiocarbamate-type heavy metal precipitant, sodium 1,3,5-hexahydrotriazinedithiocarbamate (HTDC), was prepared and used to remove coordinated copper from wastewater. In the reported dithiocarbamate-type precipitants, HTDC possesses the highest percentage of the effective functional groups. It could effectively precipitate copper to less than 0.5mgl(-1) from both synthetic and actual industrial wastewater containing CuEDTA in the range of pH 3-9. UV-vis spectral investigation and elemental analysis suggested that the precipitate was a kind of coordination supramolecular compound, [Cu(3)(HTDC)(2)](n). The toxicity characteristic leaching procedure (TCLP) and semi-dynamic leaching test (SDLT) indicated that the supramolecular precipitate was non-hazardous and stable in weak acid and alkaline conditions. Tests of an anion exchange resin D231 provided a clue to simultaneously remove excess HTDC and residual CuEDTA in practical process of wastewater treatment.

99mTcN-gatifloxacin dithiocarbamate complex. A novel multi-drug-resistance Streptococcus pneumoniae (MRSP) infaction radiotracer

International Nuclear Information System (INIS)

Syed Qaiser Shah; Mohammad Rafiullah Khan

2011-01-01

Gatifloxacin (GTN) was derivatized to its dithiocarbamate derivative and its radiolabeling with technetium-99m ( 99m Tc) using the [ 99m Tc≡N] 2+ core was investigated. The appropriateness of the 99m TcN - gatifloxacin dithiocarbamate ( 99m TcN - GTND) complex as a potential multi-drug-resistance Streptococcus pneumoniae (MRSP) infection radiotracer was evaluated in terms of stability in saline, serum, in vitro binding with MRSP and biodistribution in artificially MRSP infected Male Wistar Rats (MWR). In saline the 99m TcN - GTND complex showed more than 90% labeling yield up to 4 h with a maximum yield of 98.25 ± 0.20%, after reconstitution. In serum the 99m TcN - GTND complex showed stability up to 16 h of incubation with the appearance of insignificant 15.95% undesirable side products. The 99m TcN - GTND complex demonstrated saturated in vitro binding with MRSP with a maximum value of 75.50 ± 1.00% (at 90 min). In MWR model of group A, almost six times higher uptake of the labeled GTND was monitored in the muscle of MWR infected with live MRSP as compared to the inflamed and normal muscles. Based on the higher labeling yield in saline, in vitro stability in serum, saturated in vitro binding with live MRSP and promising biodistribution in MWR model we recommend 99m TcN - gatifloxacin dithiocarbamate complex as a potential MRSP infection radiotracer. (author)

Practical Synthesis of Pachastrissamine (Jaspine B), 2-epi-Pachastrissamine, and the 2-epi-Pyrrolidine Analogue.

Science.gov (United States)

Fujiwara, Tomoya; Liu, Bo; Niu, Wenqi; Hashimoto, Kazuki; Nambu, Hisanori; Yakura, Takayuki

2016-01-01

The practical syntheses of pachastrissamine (jaspine B), 2-epi-pachastrissamine, and the 2-epimer of the pyrrolidine analogue were accomplished via the stereoselective reduction of an allylketone derived from commercially available diethyl D-tartrate and the cross-metathesis of an allyltetrahydrofuran or allypyrrolidine with 1-tridecene as key steps.

Spectroscopic study of cadmium (II) complexes with heterocyclic dithiocarbamate ligands

International Nuclear Information System (INIS)

Garcia-Fontan, S.; Rodriguez-Seoane, P.; Casas, J.S.; Sordo, J.; Jones, M.M.

1993-01-01

Cadmium(II) dithiocarbamates [Cd(dtc) 2 ] (dtc=4-carboxamidopiperidine-1-carbodithioate, morpholine-1-carbodithioate or 4-(2-hydroxyethyl)piperazine-1-carbodithioate) and [Cd(dtc) 2 ].H 2 O (dtc=4-hydroxypiperidine-1-carbodithioate} have been prepared and characterized by thermal analysis and IR and NMR ( 13 C, 113 Cd) spectrometry. Two of these ligands have previously been shown capable of removing cadmium from its aged in vivo storage sites. The use of solid state 13 C NMR measurements to establish the coordination mode of the dithiocarbomate ligands is also examined and the difficulties which arise are discussed. (orig.)

Crystal structure of 4-methoxy-N-[(pyrrolidin-1-ylcarbothioyl]benzamide

Directory of Open Access Journals (Sweden)

Khairi Suhud

2015-04-01

Full Text Available In the title compound, C13H16N2O2S, the pyrrolidine ring has a twisted conformation on the central –CH2–CH2– bond. Its mean plane is inclined to the 4-methoxybenzoyl ring by 72.79 (15°. In the crystal, molecules are linked by N—H...O and C—H...O hydrogen bonds to the same O-atom acceptor, forming chains along [001]. The chains are linked via slipped parallel π–π interactions [inter-centroid distance = 3.7578 (13 Å], forming undulating slabs parallel to (100.

Acidic pH stimulates the production of the angiogenic CXC chemokine, CXCL8 (interleukin-8), in human adult mesenchymal stem cells via the extracellular signal-regulated kinase, p38 mitogen-activated protein kinase, and NF-kappaB pathways.

Science.gov (United States)

Bischoff, David S; Zhu, Jian-Hua; Makhijani, Nalini S; Yamaguchi, Dean T

2008-07-01

Blood vessel injury results in limited oxygen tension and diffusion leading to hypoxia, increased anaerobic metabolism, and elevated production of acidic metabolites that cannot be easily removed due to the reduced blood flow. Therefore, an acidic extracellular pH occurs in the local microenvironment of disrupted bone. The potential role of acidic pH and glu-leu-arg (ELR(+)) CXC chemokines in early events in bone repair was studied in human mesenchymal stem cells (hMSCs) treated with medium of decreasing pH (7.4, 7.0, 6.7, and 6.4). The cells showed a reciprocal increase in CXCL8 (interleukin-8, IL-8) mRNA levels as extracellular pH decreased. At pH 6.4, CXCL8 mRNA was induced >60x in comparison to levels at pH 7.4. hMSCs treated with osteogenic medium (OGM) also showed an increase in CXCL8 mRNA with decreasing pH; although, at a lower level than that seen in cells grown in non-OGM. CXCL8 protein was secreted into the medium at all pHs with maximal induction at pH 6.7. Inhibition of the G-protein-coupled receptor alpha, G(alphai), suppressed CXCL8 levels in response to acidic pH; whereas phospholipase C inhibition had no effect on CXCL8. The use of specific mitogen-activated protein kinase (MAPK) signal transduction inhibitors indicated that the pH-dependent increase in CXCL8 mRNA is due to activation of ERK and p38 pathways. The JNK pathway was not involved. NF-kappaB inhibition resulted in a decrease in CXCL8 levels in hMSCs grown in non-OGM. However, OGM-differentiated hMSCs showed an increase in CXCL8 levels when treated with the NF-kappaB inhibitor PDTC, a pyrrolidine derivative of dithiocarbamate. 2008 Wiley-Liss, Inc.

One-pot three-component route for the synthesis of S-trifluoromethyl dithiocarbamates using Togni's reagent

Czech Academy of Sciences Publication Activity Database

Halimehjani, A. Z.; Dračínský, Martin; Beier, Petr

2017-01-01

Roč. 13, Nov 24 (2017), s. 2502-2508 ISSN 1860-5397 R&D Projects: GA MŠk(CZ) LO1304 Institutional support: RVO:61388963 Keywords : dithiocarbamates * electrophilic trifluoromethylation * Togni reagents Subject RIV: CC - Organic Chemistry OBOR OECD: Organic chemistry Impact factor: 2.337, year: 2016 https://www.beilstein-journals.org/bjoc/articles/13/247

Thermal decomposition synthesis of nanorods bismuth sulphide from bismuth N-ethyl cyclohexyl dithiocarbamate complex

International Nuclear Information System (INIS)

Abdullah, Nurul Hidayah; Zainal, Zulkarnain; Silong, Sidik; Tahir, Mohamed Ibrahim Mohamed; Tan, Kar-Ban; Chang, Sook-Keng

2016-01-01

Highlights: • Bismuth N-ethyl cyclohexyl dithiocarbamate was used as single source precursor. • No surfactant was used in the preparation of Bi_2S_3 nanorods. • Pure phase orthorhombic Bi_2S_3 is obtained. • Bismuth sulphide with an average atomic ratio of Bi:S close to 2:3 is obtained. - Abstract: Nanorods of bismuth sulphide were prepared by thermal decomposition of bismuth N-ethyl cyclohexyl dithiocarbamate at different calcination duration. X-ray diffraction (XRD) analysis shows that at 400 °C, the precursor was fully decomposed to orthorhombic bismuth sulphide after 2 h of calcination. Besides, calcination duration does not affect the existence of Bi_2S_3 phase. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analyses reveal that Bi_2S_3 nanorods with an average width ranging from 29–36 nm were obtained. Energy dispersive X-ray (EDX) analysis confirmed the atomic ratio of Bi and S close to 2:3, giving a possible composition of Bi_2S_3. Direct band gap energy of Bi_2S_3 decreases from 1.83 eV to 1.54 eV as calcination time increases.

N,3,4-Trisubstituted pyrrolidines by electron transfer-induced oxidative cyclizations of N-allylic beta-amino ester enolates

Czech Academy of Sciences Publication Activity Database

Jahn, Ullrich; Kafka, František; Pohl, Radek; Jones, P.G.

2009-01-01

Roč. 65, č. 52 (2009), s. 10917-10929 ISSN 0040-4020 Institutional research plan: CEZ:AV0Z40550506 Keywords : electron transfer * pyrrolidines * oxidation Subject RIV: CC - Organic Chemistry Impact factor: 3.219, year: 2009

Crystal structure of methyl 3′-benzamido-4′-(4-methoxyphenyl-1′-methylspiro[indeno[1,2-b]quinoxaline-11,2′-pyrrolidine]-3′-carboxylate

Directory of Open Access Journals (Sweden)

Kuppan Chandralekha

2016-09-01

Full Text Available In the title compound, C35H30N4O3, the spiro C atom connects the five-membered pyrrolidine ring and the indenoquinoxaline ring system. The pyrrolidine ring adopts a twist conformation. An intramolecular N—H...N interaction between the amino group and the pyrazine ring is observed. In the crystal, molecules are linked by a pairs of C—H...O hydrogen bonds, forming inversion dimers.

Determination of cadmium in seawater by chelate vapor generation atomic fluorescence spectrometry

Science.gov (United States)

Sun, Rui; Ma, Guopeng; Duan, Xuchuan; Sun, Jinsheng

2018-03-01

A method for the determination of cadmium in seawater by chelate vapor generation (Che-VG) atomic fluorescence spectrometry is described. Several commercially available chelating agents, including ammonium pyrrolidine dithiocarbamate (APDC), sodium dimethyl dithiocarbamate (DMDTC), ammonium dibutyl dithiophosphate (DBDTP) and sodium O,O-diethyl dithiophosphate (DEDTP), are compared with sodium diethyldithiocarbamate (DDTC) for the Che-VG of cadmium, and results showed that DDTC and DEDTP had very good cadmium signal intensity. The effect of the conditions of Che-VG with DDTC on the intensity of cadmium signal was investigated. Under the optimal conditions, 85 ± 3% Che-VG efficiency is obtained for cadmium. The detection limit (3σ) obtained in the optimal conditions was 0.19 ng ml- 1. The relative standard deviation (RSD, %) for ten replicate determinations at 2 ng ml- 1 Cd was 3.42%. The proposed method was successfully applied to the ultratrace determination of cadmium in seawater samples by the standard addition method.

Dietary Exposure Assessment of Danish Consumers to Dithiocarbamate Residues in Food: a Comparison of the Deterministic and Probabilistic Approach

DEFF Research Database (Denmark)

Jensen, Bodil Hamborg; Andersen, Jens Hinge; Petersen, Annette

2008-01-01

Probabilistic and deterministic estimates of the acute and chronic exposure of the Danish populations to dithiocarbamate residues were performed. The Monte Carlo Risk Assessment programme (MCRA 4.0) was used for the probabilistic risk assessment. Food consumption data were obtained from...... the nationwide dietary survey conducted in 2000-02. Residue data for 5721 samples from the monitoring programme conducted in the period 1998-2003 were used for dithiocarbamates, which had been determined as carbon disulphide. Contributions from 26 commodities were included in the calculations. Using...... the probabilistic approach, the daily acute intakes at the 99.9% percentile for adults and children were 11.2 and 28.2 mu g kg(-1) body weight day(-1), representing 5.6% and 14.1% of the ARfD for maneb, respectively. When comparing the point estimate approach with the probabilistic approach, the outcome...

Theoretical and NMR conformational studies of β-proline oligopeptides with alternating chirality of pyrrolidine units

Science.gov (United States)

Mantsyzov, Alexey B.; Savelyev, Oleg Y.; Ivantcova, Polina M.; Bräse, Stefan; Kudryavtsev, Konstantin V.; Polshakov, Vladimir I.

2018-03-01

Synthetic β-peptides are potential functional mimetics of native α-proteins. A recently developed, novel, synthetic approach provides an effective route to the broad group of β-proline oligomers with alternating patterns of stereogenic centers. Conformation of the pyrrolidine ring, Z/E isomerism of β-peptide bonds, and hindered rotation of the neighboring monomers determine the spatial structure of this group of β-proline oligopeptides. Preferences in structural organization and corresponding thermodynamic properties are determined by NMR spectroscopy, restrained molecular dynamics and quantum mechanics. The studied β-proline oligopeptides exist in dimethyl sulfoxide solution in a limited number of conformers, with compatible energy of formation and different spatial organization. In the β-proline tetrapeptide with alternating chirality of composing pyrrolidine units, one of three peptide bonds may exist in an E configuration. For the alternating β-proline pentapeptide, the presence of an E configuration for at least of one β-peptide bond is mandatory. In this case, three peptide bonds synchronously change their configurations. Larger polypeptides may only exist in the presence of several E configurations of β-peptide bonds forming a wave-like extended structure.

Theoretical and NMR Conformational Studies of β-Proline Oligopeptides With Alternating Chirality of Pyrrolidine Units

Directory of Open Access Journals (Sweden)

Alexey B. Mantsyzov

2018-03-01

Full Text Available Synthetic β-peptides are potential functional mimetics of native α-proteins. A recently developed, novel, synthetic approach provides an effective route to the broad group of β-proline oligomers with alternating patterns of stereogenic centers. Conformation of the pyrrolidine ring, Z/E isomerism of β-peptide bonds, and hindered rotation of the neighboring monomers determine the spatial structure of this group of β-proline oligopeptides. Preferences in their structural organization and corresponding thermodynamic properties are determined by NMR spectroscopy, restrained molecular dynamics and quantum mechanics. The studied β-proline oligopeptides exist in dimethyl sulfoxide solution in a limited number of conformers, with compatible energy of formation and different spatial organization. In the β-proline tetrapeptide with alternating chirality of composing pyrrolidine units, one of three peptide bonds may exist in an E configuration. For the alternating β-proline pentapeptide, the presence of an E configuration for at least of one β-peptide bond is mandatory. In this case, three peptide bonds synchronously change their configurations. Larger polypeptides may only exist in the presence of several E configurations of β-peptide bonds forming a wave-like extended structure.

Study of sulfur adlayers on Au(1 1 1) from basic hydrolysis of piperazine bis(dithiocarbamate) sodium salt

International Nuclear Information System (INIS)

Martínez, Javier A.; Valenzuela, José; Hernandez-Tamargo, Carlos E.; Cao-Milán, Roberto; Herrera, José A.; Díaz, Jesús A.; Farías, Mario H.; Mikosch, Hans

2015-01-01

Highlights: • S adlayer formation from descomposition of piperazine bis(dithiocarbamate) sodium salt under alkaline conditions. • Quasi-rectangular octomers (eight sulfur atoms) coexist with another phase. • A DFT surface model of four S-dimers arranged as octomers reproduced real STM images. - Abstract: Sulfur adlayers on Au(1 1 1) were obtained after the interaction of a gold substrate with an alkaline solution of piperazine bis(dithiocarbamate) sodium salt. Characterization of the sulfur modified gold surface was performed by means of X-Ray Photoelectron Spectroscopy (XPS), Scanning Tunneling Microscopy (STM) and Density Functional Theory (DFT) calculations. XPS signals indicated the presence of S–Au bonds, monomeric and polymeric sulfur, and absence of nitrogen and sodium. Images from STM showed the formation of quasi-rectangular octomers in coexistence with another phase. A DFT model using the arrangement of sulfur dimers on the Au(1 1 1) surface effectively reproduced the experimental STM images

Study of sulfur adlayers on Au(1 1 1) from basic hydrolysis of piperazine bis(dithiocarbamate) sodium salt

Energy Technology Data Exchange (ETDEWEB)

Martínez, Javier A. [Instituto de Ciencia y Tecnología de Materiales (IMRE), Universidad de La Habana, Zapata y G, El Vedado, Plaza de la Revolución, La Habana 10400 (Cuba); Valenzuela, José [Centro de Nanociencias y Nanotecnología (CNyN), Universidad Nacional Autónoma de México (UNAM), km 107 Carretera Tijuana-Ensenada, Ensenada, BC 22860 (Mexico); Hernandez-Tamargo, Carlos E. [Laboratorio de Química Computacional y Teórica (LQCT), Facultad de Química, Universidad de La Habana, Zapata y G, El Vedado, Plaza de la Revolución, La Habana 10400 (Cuba); Cao-Milán, Roberto [Laboratorio de Bioinorgánica (LBI), Facultad de Química, Universidad de La Habana, Zapata y G, El Vedado, Plaza de la Revolución, La Habana 10400 (Cuba); Herrera, José A. [Instituto de Ciencia y Tecnología de Materiales (IMRE), Universidad de La Habana, Zapata y G, El Vedado, Plaza de la Revolución, La Habana 10400 (Cuba); Díaz, Jesús A.; Farías, Mario H. [Centro de Nanociencias y Nanotecnología (CNyN), Universidad Nacional Autónoma de México (UNAM), km 107 Carretera Tijuana-Ensenada, Ensenada, BC 22860 (Mexico); Mikosch, Hans [Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/E164-EC, 1060 Vienna (Austria); and others

2015-08-01

Highlights: • S adlayer formation from descomposition of piperazine bis(dithiocarbamate) sodium salt under alkaline conditions. • Quasi-rectangular octomers (eight sulfur atoms) coexist with another phase. • A DFT surface model of four S-dimers arranged as octomers reproduced real STM images. - Abstract: Sulfur adlayers on Au(1 1 1) were obtained after the interaction of a gold substrate with an alkaline solution of piperazine bis(dithiocarbamate) sodium salt. Characterization of the sulfur modified gold surface was performed by means of X-Ray Photoelectron Spectroscopy (XPS), Scanning Tunneling Microscopy (STM) and Density Functional Theory (DFT) calculations. XPS signals indicated the presence of S–Au bonds, monomeric and polymeric sulfur, and absence of nitrogen and sodium. Images from STM showed the formation of quasi-rectangular octomers in coexistence with another phase. A DFT model using the arrangement of sulfur dimers on the Au(1 1 1) surface effectively reproduced the experimental STM images.

Diastereomerically and enantiomerically pure 2,3-disubstituted pyrrolidines from 2,3-aziridin-1-ols using a sulfoxonium ylide: a one-carbon homologative relay ring expansion.

Science.gov (United States)

Schomaker, Jennifer M; Bhattacharjee, Somnath; Yan, Jun; Borhan, Babak

2007-02-21

An ylide-based aza-Payne rearrangement of 2,3-aziridin-1-ols leads to an efficient process for the preparation of pyrrolidines. The aza-Payne rearrangement under basic reaction conditions favors the formation of epoxy amines. Subsequent nucleophilic attack of the epoxide by the ylide yields a bis-anion, which upon a 5-exo-tet ring-closure yields the desired pyrrolidine, thus completing the relay of the three-membered to the five-membered nitrogen-containing ring system. This process takes place with complete transfer of stereochemical fidelity and can be applied to sterically hindered aziridinols.

Selective Flow-Injection Quantification of Ultra-trace Amounts of Cr(VI) via On-line Complexation and Preconcentration with APDC Followed by Determination by Electrothermal Atomic Absorption Spectrometry

DEFF Research Database (Denmark)

Nielsen, Steffen; Hansen, Elo Harald

1998-01-01

A rapid, sensitive and selective time-based flow injection (FI) preconcentration procedure is described for the determination of ultra-trace amounts of Cr(VI) via on-line reaction with ammonium pyrrolidine dithiocarbamate (APDC) and formation of the Cr(VI)-PDC complex. The preconcentration...... to direct introduction of 55 mu l samples, yielding a detection limit (3 sigma) of 4.2 ng l(-1). The sample frequency was 21.2 samples per hour. The proposed method was evaluated by analyzing drinking water, a NIST Cr(VI)-reference material and synthetic sea water. A major contribution to successful...

Determination of traces of silver in waters by anion exchange and atomic absorption spectrophotometry

Science.gov (United States)

Chao, T.T.; Fishman, M. J.; Ball, J.W.

1969-01-01

A method has been developed for the accurate determination of 0.1-1 ??g of silver per liter of water. The method permits stabilization of silver in water without loss to container walls. Optimum conditions have been established for the complete recovery of silver from water with an anion-exchange column, for quantitative elution of silver from the resin, and for measurement of silver by atomic absorption spectrophotometry after chelation with ammonium pyrrolidine dithiocarbamate and extraction of the chelate with MIBK. Silver in the 1-10 ??g 1 range can be determined by extraction without pre-concentration on an ion-exchange resin. ?? 1969.

Gold nanoparticle-based fluorescent sensor for the analysis of dithiocarbamate pesticides in water

DEFF Research Database (Denmark)

Senkbeil, Silja; Lafleur, Josiane P.; Jensen, Thomas Glasdam

2012-01-01

Pesticides play a key role in the high yields achieved in modern agricultural food production. Besides their positive effect on increasing productivity they are intentionally toxic, often towards non-target organisms and contaminated food products can have a serious impact on human...... and environmental health. This paper demonstrates the potential of a gold nanoparticle-based microfluidic sensor for in field detection of dithiocarbamate pesticides at remote locations. Combining the attractive optical properties of gold nanoparticles with on chip mixing and detection, using a simple digital...

Matrix separation by chelation to prepare biological materials for isotopic zinc analysis by inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Durrant, S.F.; Krushevska, A.; Amarasiriwardena, D.; Argentine, M.D.; Romon-Guesnier, S.; Barnes, R.M.

1994-01-01

Following an evaluation of three chelating resins [Chelex-100, poly(dithiocarbamate) (PDTC) and carboxymethylated poly(ethyleneimine)-poly(methylenepolyphenylene) isocyanate (CPPI)], a procedure was established with the last of these for the separation of Zn from biological matrix elements prior to 70 Zn: 68 Zn isotopic analysis by inductively coupled plasma mass spectrometry (ICP-MS). The method was verified by establishing Zn recoveries and by determining its effectiveness in removing Cl and Na from buffered test solutions. Calcium, Na, and Zn concentration data were determined by inductively coupled plasma atomic emission spectrometry. Chlorine was measured by electrothermal vaporization ICP-MS. The efficacy of the technique was demonstrated by the determination of zinc isotope ratios in bovine milk and human urine. (Author)

Synthesis and Biological Evaluation of Some Novel Dithiocarbamate Derivatives

Directory of Open Access Journals (Sweden)

Begüm Nurpelin Sağlık

2014-01-01

Full Text Available 18 novel dithiocarbamate derivatives were synthesized in order to investigate their inhibitory potency on acetylcholinesterase enzyme and antimicrobial activity. Structures of the synthesized compounds were elucidated by spectral data and elemental analyses. The synthesized compounds showed low enzyme inhibitory activity. However, they displayed good antimicrobial activity profile. Antibacterial activity of compounds 4a, 4e, and 4p (MIC = 25 μg/mL was equal to that of chloramphenicol against Klebsiella pneumoniae (ATCC 700603 and Escherichia coli (ATCC 35218. Most of the compounds exhibited notable antifungal activity against Candida albicans (ATCC 10231, Candida glabrata (ATCC 90030, Candida krusei (ATCC 6258, and Candida parapsilosis (ATCC 7330. Moreover, compound 4a, which carries piperidin-1-yl substituent and dimethylthiocarbamoyl side chain as variable group, showed twofold better anticandidal effect against all Candida species than reference drug ketoconazole.

Synthesis, spectral and thermal studies of pyridyl adducts of Zn(II) and Cd(II) dithiocarbamates, and their use as single source precursors for ZnS and CdS nanoparticles

OpenAIRE

Onwudiwe, Damian C.; Strydom, Christien A.; Jordaan, Anine; Oluwafemi, Oluwatobi S.; Hosten, Eric

2014-01-01

The synthesis, spectroscopic characterisation, and thermal studies of pyridyl adducts of Zn(II) and Cd(II) complexes of N-ethyl-N-phenyl dithiocarbamate, represented as [ZnL2py] and [CdL2py2], are reported. Single-crystal X-ray structural analysis of the Zn compound showed that it is five-coordinate with four sulphurs from dithiocarbamate and one nitrogen from pyridine in a distorted square pyramidal geometry. The thermogravimetric studies indicate that the zinc and cadmium compou...

Di-2-pyridylhydrazone Dithiocarbamate Butyric Acid Ester Exerted Its Proliferative Inhibition against Gastric Cell via ROS-Mediated Apoptosis and Autophagy

Directory of Open Access Journals (Sweden)

Xingshuang Guo

2018-01-01

Full Text Available Diversified biological activities of dithiocarbamates have attracted widespread attention; improving their feature or exploring their potent action of mechanism is a hot topic in medicinal research. Herein, we presented a study on synthesis and investigation of a novel dithiocarbamate, DpdtbA (di-2-pyridylhydrazone dithiocarbamate butyric acid ester, on antitumor activity. The growth inhibition assay revealed that DpdtbA had important antitumor activity for gastric cancer (GC cell lines (IC50 = 4.2 ± 0.52 μM for SGC-7901, 3.80 ± 0.40 μM for MGC-803. The next study indicated that growth inhibition is involved in ROS generation in mechanism; accordingly, the changes in mitochondrial membrane permeability, apoptotic genes, cytochrome c, bax, and bcl-2 were observed, implying that the growth inhibition of DpdtbA is involved in ROS-mediated apoptosis. On the other hand, the upregulated p53 upon DpdtbA treatment implied that p53 could also mediate the apoptosis. Yet the excess generation of ROS induced by DpdtbA led to cathepsin D translocation and increase of autophagic vacuoles and LC3-II, demonstrating that autophagy was also a contributor to growth inhibition. Further investigation showed that DpdtbA could induce cell cycle arrest at the G1 phase. This clearly indicated the growth inhibition of DpdtbA was via triggering ROS formation and evoking p53 response, consequently leading to alteration in gene expressions that are related to cell survival.

Design, synthesis, molecular docking and biological evaluation of new dithiocarbamates substituted benzimidazole and chalcones as possible chemotherapeutic agents.

Science.gov (United States)

Bacharaju, Keerthana; Jambula, Swathi Reddy; Sivan, Sreekanth; Jyostnatangeda, Saritha; Manga, Vijjulatha

2012-05-01

A series of novel dithiocarbamates with benzimidazole and chalcone scaffold have been designed synthesised and evaluated for their antimitotic activity. Compounds 4c and 9d display the most promising antimitotic activity with IC(50) of 1.66 μM and 1.52 μM respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

Synthesis of a drug-like focused library of trisubstituted pyrrolidines using integrated flow chemistry and batch methods.

Science.gov (United States)

Baumann, Marcus; Baxendale, Ian R; Kuratli, Christoph; Ley, Steven V; Martin, Rainer E; Schneider, Josef

2011-07-11

A combination of flow and batch chemistries has been successfully applied to the assembly of a series of trisubstituted drug-like pyrrolidines. This study demonstrates the efficient preparation of a focused library of these pharmaceutically important structures using microreactor technologies, as well as classical parallel synthesis techniques, and thus exemplifies the impact of integrating innovative enabling tools within the drug discovery process.

Radiosynthesis and biodistribution of 99mTcN-Garenoxacin dithiocarbamate complex a potential infection imaging agent

International Nuclear Information System (INIS)

Syed Qaiser Shah; Aakif Ullah Khan; Muhammad Rafiullah Khan

2011-01-01

Garenoxacin (GXN) was modified to its dithiocarbamate followed by radiolabeling with technetium-99m ( 99m Tc) through [ 99m Tc-N] 2+ core. The suitability of the 99m TcN-Garenoxacin dithiocarbamate (GXND) complex as a potential multiresistant Staphylococcus aureus (MDRSA) and penicillin-resistant Streptococci (PRSC) infection radiotracer was assessed in artificially infected rats (AFRT). The radiolabeled complex was investigated for its radiochemical purity (RCP), permanence in serum using HPLC and TLC methods. In vitro binding with MDRSA and PRSC was performed at 37 deg C. The 99m TcN-GXND showed maximum RCP of 98.00 ± 0.22% and remained more than 90% stable up to 4 h. The 99m TcN-GXND showed saturated in vitro binding with living MDRSA and PRSC, respectively. The complex showed normal biodistribution in healthy rats (HRT), however in AFRT, seven fold uptakes was observed in infected muscle as compared to inflamed and normal muscles. Based on the high RCP, stability in serum, better in vitro binding with bacteria, biodistribution behavior and the target to non-target (infected to inflamed muscle) ratio, we recommend the 99m TcN-GXND complex for in vivo investigation of MDRSA and PRSC infection in human. (author)

A new fluorescent pyrene–pyridine dithiocarbamate probe: A chemodosimeter to detect Hg2+ in pure aqueous medium and in live cells

International Nuclear Information System (INIS)

Singh, Vikram; Srivastava, Priyanka; PrakashVerma, Shiv; Misra, Arvind; Das, Parimal; Singh, Nanhai

2014-01-01

A new pyrene–pyridine dithiocarbamate based fluorescent chemodosimeter, potassium (pyren-1-ylmethyl)(pyridin-2-ylmethyl)dithiocarbamate (L1) has been designed and synthesized. The chemodosimeter shows high selectivity and sensitivity (5.2 ppb) for Hg 2+ in pure aqueous medium in which emission intensity was quenched by ≈80% due to the formation of new cyclized species, 1. The probe behaves as a chemodosimeter for Hg 2+ ions and forms Hg 2+ triggered cyclised imidazoline species with approximate detection time of 50 s and exhibits both colorimetric and fluorometric changes on detection of Hg 2+ ion. Color of the probe (L1) changed from green to colorless visible to the naked eye and from green to dark blue upon the addition of Hg 2+ ions under UV light. The Hg 2+ triggered cyclization reaction was confirmed by spectral data analysis and a single crystal structure determination of the cyclised entity 2 obtained from the model compound potassium benzyl(pyridin-2-ylmethyl) dithiocarbamate (L2). L1 finds its application for detection of Hg 2+ ions on paper strips, and in BSA (bovine serum albumin) medium. L1 is also applicable for the monitoring of Hg 2+ ion in NIH3T3 live cells. - Highlights: • Efficient chemodosimeter to detect Hg 2+ ions in pure aqueous medium. • Hg 2+ triggered cyclisation and formation of imidazoline species. • Probe exhibit both colorimetric and fluorometric changes • Probe is applicable to detect Hg 2+ in live cells and on cellulose paper strips

Simultaneous separation of copper, cadmium and cobalt from sea-water by co-flotation with octadecylamine and ferric hydroxide as collectors.

Science.gov (United States)

Cabezon, L M; Caballero, M; Cela, R; Perez-Bustamante, J A

1984-08-01

A method is proposed for the simultaneous quantitative separation of traces ofCu(II), Cd(II) and Co(II) from sea-water samples by means of the co-flotation (adsorbing colloid flotation) technique with ferric hydroxide as co-precipitant and octadecylamine as collector. The experimental parameters have been studied and optimized. The drawbacks arising from the low solubility of octadecylamine and the corresponding sublates in water have been avoided by use of a 6M hydrochloric acid-MIBK-ethanol (1:2:2 v v ) mixture. The results obtained by means of the proposed method have been compared with those given by the usual ammonium pyrrolidine dithiocarbamate/MIBK extraction method.

Selective Flow Injection Analysis of Ultra-trace Amounts of Cr(VI), Preconcentration of It by Solvent Extraction, and Determination by Electrothermal Atomic Absorption Spectrometry (ETAAS)

DEFF Research Database (Denmark)

Nielsen, Steffen; Sturup, Stefan; Spliid, Henrik

1999-01-01

(IBMK). The Cr(VI) is complexed by reaction with ammonium pyrrolidine dithiocarbamate (APDC), and the non-charged Cr(VI)-PDC chelate formed is extracted into IBMK in a knotted reactor made from PTFE tubing. The organic extractant is separated from the aqueous phase by a gravity phase separator......(VI) was achieved after preconcentration for 99 s at a sample flow rate of 5.5 ml min-1, as compared to direct introduction of 55 mul of sample, yielding a detection limit (3sigma) of 3.3 ng l-1. The sampling frequency was 24.2 samples h-1. The proposed method was successfully evaluated by analyzing a NIST Cr...

1-Benzyl-3′-[(1H-indol-3-ylcarbonyl]-1′-methyl-2-oxo-4′-(pyridin-3-ylspiro[indoline-3,2′-pyrrolidine]-3′-carbonitrile

Directory of Open Access Journals (Sweden)

P. Seethalakshmi

2016-11-01

Full Text Available In the title compound, C34H27N5O2, the central pyrrolidine ring adopts an envelope conformation, with the N atom as the flap. The mean planes of the two indoline ring systems are inclined to the mean plane of the central pyrrolidine ring by 86.26 (9 and 69.30 (9°, respectively. The dihedral angle between the benzene and pyridine rings is 75.09 (11°. In the crystal, molecules are linked by N—H...N and C—H...N hydrogen bonds, forming sheets parallel to the ab plane.

A new fluorescent pyrene–pyridine dithiocarbamate probe: A chemodosimeter to detect Hg{sup 2+} in pure aqueous medium and in live cells

Energy Technology Data Exchange (ETDEWEB)

Singh, Vikram; Srivastava, Priyanka [Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi-221005 (India); PrakashVerma, Shiv [Centre for Genetic Disorders, Faculty of Science, Banaras Hindu University, Varanasi-221005 (India); Misra, Arvind [Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi-221005 (India); Das, Parimal [Centre for Genetic Disorders, Faculty of Science, Banaras Hindu University, Varanasi-221005 (India); Singh, Nanhai, E-mail: nsinghbhu@gmail.com [Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi-221005 (India)

2014-10-15

A new pyrene–pyridine dithiocarbamate based fluorescent chemodosimeter, potassium (pyren-1-ylmethyl)(pyridin-2-ylmethyl)dithiocarbamate (L1) has been designed and synthesized. The chemodosimeter shows high selectivity and sensitivity (5.2 ppb) for Hg{sup 2+} in pure aqueous medium in which emission intensity was quenched by ≈80% due to the formation of new cyclized species, 1. The probe behaves as a chemodosimeter for Hg{sup 2+} ions and forms Hg{sup 2+} triggered cyclised imidazoline species with approximate detection time of 50 s and exhibits both colorimetric and fluorometric changes on detection of Hg{sup 2+} ion. Color of the probe (L1) changed from green to colorless visible to the naked eye and from green to dark blue upon the addition of Hg{sup 2+} ions under UV light. The Hg{sup 2+} triggered cyclization reaction was confirmed by spectral data analysis and a single crystal structure determination of the cyclised entity 2 obtained from the model compound potassium benzyl(pyridin-2-ylmethyl) dithiocarbamate (L2). L1 finds its application for detection of Hg{sup 2+} ions on paper strips, and in BSA (bovine serum albumin) medium. L1 is also applicable for the monitoring of Hg{sup 2+} ion in NIH3T3 live cells. - Highlights: • Efficient chemodosimeter to detect Hg{sup 2+} ions in pure aqueous medium. • Hg{sup 2+} triggered cyclisation and formation of imidazoline species. • Probe exhibit both colorimetric and fluorometric changes • Probe is applicable to detect Hg{sup 2+} in live cells and on cellulose paper strips.

Hypoxia-Induced Collagen Synthesis of Human Lung Fibroblasts by Activating the Angiotensin System

Directory of Open Access Journals (Sweden)

Shan-Shan Liu

2013-12-01

Full Text Available The exact molecular mechanism that mediates hypoxia-induced pulmonary fibrosis needs to be further clarified. The aim of this study was to explore the effect and underlying mechanism of angiotensin II (Ang II on collagen synthesis in hypoxic human lung fibroblast (HLF cells. The HLF-1 cell line was used for in vitro studies. Angiotensinogen (AGT, angiotensin converting enzyme (ACE, angiotensin II type 1 receptor (AT1R and angiotensin II type 2 receptor (AT2R expression levels in human lung fibroblasts were analysed using real-time polymerase chain reaction (RT-PCR after hypoxic treatment. Additionally, the collagen type I (Col-I, AT1R and nuclear factor κappaB (NF-κB protein expression levels were detected using Western blot analysis, and NF-κB nuclear translocation was measured using immunofluorescence localization analysis. Ang II levels in HLF-1 cells were measured with an enzyme-linked immunosorbent assay (ELISA. We found that hypoxia increased Col-I mRNA and protein expression in HLF-1 cells, and this effect could be inhibited by an AT1R or AT2R inhibitor. The levels of NF-κB, RAS components and Ang II production in HLF-1 cells were significantly increased after the hypoxia exposure. Hypoxia or Ang II increased NF-κB-p50 protein expression in HLF-1 cells, and the special effect could be inhibited by telmisartan (TST, an AT1R inhibitor, and partially inhibited by PD123319, an AT2R inhibitor. Importantly, hypoxia-induced NF-κB nuclear translocation could be nearly completely inhibited by an AT1R or AT2R inhibitor. Furthermore pyrrolidine dithiocarbamate (PDTC, a NF-κB blocker, abolished the expression of hypoxia-induced AT1R and Col-I in HLF-1 cells. Our results indicate that Ang II-mediated NF-κB signalling via ATR is involved in hypoxia-induced collagen synthesis in human lung fibroblasts.

Humic acid in drinking well water induces inflammation through reactive oxygen species generation and activation of nuclear factor-κB/activator protein-1 signaling pathways: A possible role in atherosclerosis

Energy Technology Data Exchange (ETDEWEB)

Hseu, You-Cheng [Department of Cosmeceutics, China Medical University, Taichung 40402, Taiwan (China); Department of Molecular and Cellular Oncology, University of Texas, MD Anderson Cancer Center, TX 77030 (United States); Senthil Kumar, K.J. [Department of Cosmeceutics, China Medical University, Taichung 40402, Taiwan (China); Chen, Chih-Sheng; Cho, Hsin-Ju; Lin, Shu-Wei; Shen, Pei-Chun [Institute of Nutrition, China Medical University, Taichung 40402, Taiwan (China); Lin, Cheng-Wen [Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung 40402, Taiwan (China); Lu, Fung-Jou [Institute of Medicine, Chun Shan Medical University, Taichung 40201, Taiwan (China); Yang, Hsin-Ling, E-mail: hlyang@mail.cmu.edu.tw [Institute of Nutrition, China Medical University, Taichung 40402, Taiwan (China); Department of Molecular and Cellular Oncology, University of Texas, MD Anderson Cancer Center, TX 77030 (United States)

2014-01-15

Humic acid (HA) has been implicated as one of the etiological factors in the peripheral vasculopathy of blackfoot disease (BFD) in Taiwan. However, the underlying pathophysiological mechanisms of BFD are not well defined. In this study, we used an in vitro and in vivo model, in which HA (25–200 μg/mL) activated macrophages to produce pro-inflammatory molecules by activating their transcriptional factors. HA exposure induced NO and PGE{sub 2} production followed by induction of iNOS and COX-2 through NF-κB/AP-1 transactivation in macrophages. In addition, the production of TNF-α and IL-1β was significantly increased by HA. Moreover, HA-induced iNOS and COX-2 expression were down-regulated by the NF-κB and AP-1 inhibitors pyrrolidine dithiocarbamate (PDTC) and Tanshinone, respectively. Furthermore, generations of ROS and nitrotyrosine, as well as activation of the AKT and MAPKs signaling cascades were observed after HA exposure. Specifically, HA-induced NF-κB activation was mediated by ROS and AKT, and that HA-induced AP-1 activation was mediated by JNK and ERK. Notably, HA-mediated AKT, JNK, and ERK activation was ROS-independent. The inflammatory potential of HA was correlated with increased expression of HO-1 and Nrf2. Furthermore, an in vivo study confirms that mice exposed to HA, the serum levels of TNF-α and IL-1β was significantly increased in a dose-dependent manner. This report marks the first confirmation that environmental exposure of HA induces inflammation in macrophages, which may be one of the main causes of early atherogenesis in blackfoot disease. - Highlights: • Humic acid (HA) induce pro-inflammatory cytokines and mediators in macrophages. • HA-induced inflammation is mediated by ROS and NF-κB/AP-1 signaling pathways. • The inflammatory potential of HA correlated with activation of Nrf2/HO-1 genes. • HA exposure to mice increased pro-inflammatory cytokines production in vivo. • HA may be one of the main causes of early

Humic acid in drinking well water induces inflammation through reactive oxygen species generation and activation of nuclear factor-κB/activator protein-1 signaling pathways: A possible role in atherosclerosis

International Nuclear Information System (INIS)

Hseu, You-Cheng; Senthil Kumar, K.J.; Chen, Chih-Sheng; Cho, Hsin-Ju; Lin, Shu-Wei; Shen, Pei-Chun; Lin, Cheng-Wen; Lu, Fung-Jou; Yang, Hsin-Ling

2014-01-01

Humic acid (HA) has been implicated as one of the etiological factors in the peripheral vasculopathy of blackfoot disease (BFD) in Taiwan. However, the underlying pathophysiological mechanisms of BFD are not well defined. In this study, we used an in vitro and in vivo model, in which HA (25–200 μg/mL) activated macrophages to produce pro-inflammatory molecules by activating their transcriptional factors. HA exposure induced NO and PGE 2 production followed by induction of iNOS and COX-2 through NF-κB/AP-1 transactivation in macrophages. In addition, the production of TNF-α and IL-1β was significantly increased by HA. Moreover, HA-induced iNOS and COX-2 expression were down-regulated by the NF-κB and AP-1 inhibitors pyrrolidine dithiocarbamate (PDTC) and Tanshinone, respectively. Furthermore, generations of ROS and nitrotyrosine, as well as activation of the AKT and MAPKs signaling cascades were observed after HA exposure. Specifically, HA-induced NF-κB activation was mediated by ROS and AKT, and that HA-induced AP-1 activation was mediated by JNK and ERK. Notably, HA-mediated AKT, JNK, and ERK activation was ROS-independent. The inflammatory potential of HA was correlated with increased expression of HO-1 and Nrf2. Furthermore, an in vivo study confirms that mice exposed to HA, the serum levels of TNF-α and IL-1β was significantly increased in a dose-dependent manner. This report marks the first confirmation that environmental exposure of HA induces inflammation in macrophages, which may be one of the main causes of early atherogenesis in blackfoot disease. - Highlights: • Humic acid (HA) induce pro-inflammatory cytokines and mediators in macrophages. • HA-induced inflammation is mediated by ROS and NF-κB/AP-1 signaling pathways. • The inflammatory potential of HA correlated with activation of Nrf2/HO-1 genes. • HA exposure to mice increased pro-inflammatory cytokines production in vivo. • HA may be one of the main causes of early atherogenesis

Assessment of Dithiocarbamate Residues on Tomatoes Conventionally Grown in Uganda and the Effect of Simple Washing to Reduce Exposure Risk to Consumers

DEFF Research Database (Denmark)

Atuhaire, Aggrey; Kaye, Emmanuel; Mutambuze, Innocent Louis

2017-01-01

Pesticide misuse by farmers poses health risks to consumers. This study assessed the level of dithiocarbamate residues in tomatoes acquired from 20 farmers and 25 market vendors in Wakiso District, how simple washing affects these residues, and the potential chronic health risk for Ugandans eatin...

Ethyl 3-hydroxy-13-methyl-4′-phenyl-2′-(3,4,5-trimethoxyphenyl-6,7,8,9,11,12,13,14,15,16-decahydrospiro[cyclopenta[a]phenanthrene-16,3′-pyrrolidine]-5′-carboxylate

Directory of Open Access Journals (Sweden)

R. Murugan

2008-11-01

Full Text Available In the title compound, C39H45NO7,the pyrrolidine ring is connected to an estrone group, a trimethoxy benzene and a phenyl ring. The pyrrolidine ring exhibits a twist conformation and the other five-membered ring an envelope conformation. Molecules are linked by N—H...O hydrogen bonds, C—H...π interactions and C—H...O hydrogen bonds.

Ligand-Enabled γ-C(sp(3))-H Olefination of Amines: En Route to Pyrrolidines.

Science.gov (United States)

Jiang, Heng; He, Jian; Liu, Tao; Yu, Jin-Quan

2016-02-17

Pd(II)-catalyzed olefination of γ-C(sp(3))-H bonds of triflyl (Tf) and 4-nitrobenzenesulfonyl (Ns) protected amines is achieved. Subsequent aza-Wacker oxidative cyclization or conjugate addition of the olefinated intermediates provides a variety of C-2 alkylated pyrrolidines. Three pyridine- and quinoline-based ligands are developed to match different classes of amine substrates, demonstrating a rare example of ligand-enabled C(sp(3))-H olefination reactions. The use of Ns protecting group to direct C(sp(3))-H activation of alkyl amines is also a significant step toward practical C-H functionalizations of alkyl amines.

Synthesis and Spectral Studies of Ni(II Dithiocarbamate Complexes and Their Use as Precursors for Nickel Sulphides Nanocrystals

Directory of Open Access Journals (Sweden)

Azile Nqombolo

2016-01-01

Full Text Available Ni(II dithiocarbamate complexes have been synthesized and characterized by UV-Vis, FTIR, and NMR spectroscopic techniques. Electronic spectra measurements indicate that the complexes are four-coordinate square planar geometry while the FTIR confirmed that the dithiocarbamates act as bidentate chelating ligands. The compounds were used as single source precursors and thermolysed at 220°C to prepare HDA-capped NiS nanocrystals which were characterized by absorption and photoluminescence (PL spectra measurements, powder X-ray diffraction (PXRD, transmission electron microscopy (TEM, scanning electron microscopy (SEM, and energy dispersive spectroscopy (EDS. Absorption spectra studies showed that the synthesized NiS nanoparticles are blue-shifted relative to the bulk material and PL studies showed emission maxima that are red-shifted compared to the absorption band edges. The XRD patterns of the as-prepared NiS nanoparticles revealed cubic crystalline phases. TEM images showed spherical and close-to-spherical nanocrystals with the size in the range 12–38 nm for NiS1, 8–11 nm for NiS2, and 9–16 nm for NiS3. SEM images showed homogeneous surface morphology and EDS confirmed the presence of Ni and S and the formation of NiS nanoparticles.

Determination of heavy metals at traces level in leached samples by energy dispersive x-ray fluorescence technique

International Nuclear Information System (INIS)

Simabuco, Silvana M.; Nascimento Filho, Virgilio F. do; Inacio, Graziela R.; Navarro, Angela N.

1996-01-01

In landfill solid residues are disposed in the soil. When made based on technical criteria and specifically operation patterns a safe confinement is warranted according to environmental and public health protection. However, when the disposal is made by a random and unsuitable way serious problems can be caused as groundwater and superficial water contamination through leach action, indicating the usefulness of monitoring landfills. In this way energy dispersive X-ray fluorescence analysis with radioisotopic excitation was applied to evaluate the concentrations of heavy metals at trace levels in leached samples from the Americana City Landfill with pre-concentration of the elements by a non-specific precipitating agent, called ammonium pyrrolidine dithiocarbamate (APDC). (author)

Determination of heavy metals at traces level in leached samples by energy dispersive x-ray fluorescence technique; Determinacao de metais pesados a nivel de tracos em amostras de chorume pela tecnica de fluorescencia de raios X por dispersao de energia

Energy Technology Data Exchange (ETDEWEB)

Simabuco, Silvana M. [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Civil; Nascimento Filho, Virgilio F. do; Inacio, Graziela R.; Navarro, Angela N. [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Secao de Metodologia de Radioisotopos

1996-07-01

In landfill solid residues are disposed in the soil. When made based on technical criteria and specifically operation patterns a safe confinement is warranted according to environmental and public health protection. However, when the disposal is made by a random and unsuitable way serious problems can be caused as groundwater and superficial water contamination through leach action, indicating the usefulness of monitoring landfills. In this way energy dispersive X-ray fluorescence analysis with radioisotopic excitation was applied to evaluate the concentrations of heavy metals at trace levels in leached samples from the Americana City Landfill with pre-concentration of the elements by a non-specific precipitating agent, called ammonium pyrrolidine dithiocarbamate (APDC). (author)

Synthesis and Structure Determination of Di-tert-butyltin (IV) Dithiocarbamate)

International Nuclear Information System (INIS)

Amirah Faizah Abdul Muthalib; Ibrahim Baba; Yang Farina Abdul Aziz; Mohd Wahid Samsudin

2013-01-01

New diorganotin (IV) dithiocarbamate complexes have been synthesized from di-tert-butyltin (IV) dichloride, N-dialkylamine and carbon disulphide. Elemental and gravimetric analysis confirmed the general formula of these complexes as (t- C 4 H 9 ) 2 Sn[S 2 CNR 1 R 2 ] 2 (R 1 = CH 3 , C 2 H 5 , C 7 H 7 dan R 2 = C 2 H 5 , C 6 H 11 , iC 3 H 7 , CH 3 , C 2 H 5 , C 4 H 9 , C 7 H 7 ). The structures of these complexes have been elucidated on the basis of infrared, ultraviolet, 1 H, 13 C and 119 Sn NMR spectroscopy and X-ray crystallography. The infrared spectra of these complexes showed three main peaks for v(C-N), v(C-S) and v(Sn-S) bands that appeared in the region of 1447-1496, 947-988 and 352-370 cm -1 , respectively. The 13 C NMR spectrum showed the chemical shift for ?(N 13 CS 2 ) in the range of 199.1-201.8 ppm. X-ray single crystal structure (C 4 H 9 ) 2 Sn[S 2 CN(CH 3 )(iC 3 H 7 )] 2 demonstrated a six-coordination geometry around the tin atom adopting a monoclinic system with a space group of P2/n with a = 11.2934(11) Angstrom, b = 7.0175(7) Angstrom, c = 15.6894(15) Angstrom; β = 95.016(1) degree. The (N-benzyl-N-ethyl dithiocarbamato)chloride di-tert-butyltin(IV) and (N,N-dibenzyl dithiocarbamato)chloride-di-(tert-butyl)tin(IV) formed a different geometry with one dithiocarbamate ligand and one chlorine atom attached to the tin centre to form a five-coordinate structure. Crystal of (N-benzyl-N-ethyl dithiocarbamato)chloride di-tert-butyltin(IV) adopts a triclinic system with space group of P1 and cell parameter of a = 8.6140 (2) Angstrom, b = 10.9604 (3) Angstrom, c = 11.4765 (3) Angstrom; α = 91.858 (2) degree, β = 96.193 (2) degree, γ = 96.011 (2) degree, while (N,N-dibenzyl dithiocarbamato)chloride-di-(tert-butyl)tin(IV) adopts a monoclinic system with space group of P2 i with cell parameter a = 9.0600 (2) Angstrom, b = 10.9238 (2) Angstrom, c = 12.7845 (3) Angstrom; β= 102.759 (2) degree. (author)

Design and synthesis of new of 3-(benzo[d]isoxazol-3-yl)-1-substituted pyrrolidine-2, 5-dione derivatives as anticonvulsants.

Science.gov (United States)

Malik, Sachin; Ahuja, Priya; Sahu, Kapendra; Khan, Suroor Ahmad

2014-09-12

A series of 3-(benzo[d]isoxazol-3-yl)-N-substituted pyrrolidine-2, 5-dione (7a-7d, 8a-8d, 9a-9c) have been prepared and evaluated for their anticonvulsant activities. Preliminary anticonvulsant activity was performed using maximal electroshock (MES) and subcutaneous pentylenetetrazole (scPTZ) tests after intraperitoneal (ip) injection into mice, which are the most widely employed models for early identification of anticonvulsant candidate. The acute neurological toxicity (NT) was determined applying rotorod test. The quantitative evaluation after oral administration in rats showed that the most active was 3-(benzo[d]isoxazol-3-yl)-1-(4-fluorophenyl) pyrrolidine-2, 5-dione (8a) with ED50 values of 14.90 mg/kg. Similarly the most potent in scPTZ was 3-(benzo[d]isoxazol-3-yl)-1-cyclohexylpyrrolidine-2, 5-dione (7d) with ED50 values of 42.30 mg/kg. These molecules were more potent and less neurotoxic than phenytoin and ethosuximide which were used as reference antiepileptic drugs. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Structure-Activity Relationship Study of Ionotropic Glutamate Receptor Antagonist (2S,3R)-3-(3-Carboxyphenyl)pyrrolidine-2-carboxylic Acid

DEFF Research Database (Denmark)

Krogsgaard-Larsen, Niels; Storgaard, Morten; Møller, Charlotte

2015-01-01

Herein we describe the first structure-activity relationship study of the broad-range iGluR antagonist (2S,3R)-3-(3-carboxyphenyl)pyrrolidine-2-carboxylic acid (1) by exploring the pharmacological effect of substituents in the 4, 4', or 5' positions and the bioisosteric substitution of the distal...... carboxylic acid for a phosphonic acid moiety. Of particular interest is a hydroxyl group in the 4' position 2a which induced a preference in binding affinity for homomeric GluK3 over GluK1 (Ki = 0.87 and 4.8 μM, respectively). Two X-ray structures of ligand binding domains were obtained: 2e in GluA2-LBD...... and 2f in GluK1-LBD, both at 1.9 Å resolution. Compound 2e induces a D1-D2 domain opening in GluA2-LBD of 17.3-18.8° and 2f a domain opening in GluK1-LBD of 17.0-17.5° relative to the structures with glutamate. The pyrrolidine-2-carboxylate moiety of 2e and 2f shows a similar binding mode as kainate...

Selective visual detection of Pb(II) ion via gold nanoparticles coated with a dithiocarbamate-modified 4′-aminobenzo-18-crown-6

International Nuclear Information System (INIS)

Mehta, Vaibhavkumar N.; Kailasa, Suresh Kumar; Solanki, Jignasa N.

2014-01-01

We have developed a crown ether based selective colorimetric sensing scheme for the determination of Pb(II) ion by using gold nanoparticles modified with dithiocarbamate derivative of 4′-aminobenzo-18-crown-6 that acts as a colorimetric probe. Monodisperse Au-NPs were prepared by reacting 4′-aminobenzo-18-crown-6 with carbon disulfide to generate the dithiocarbamate ligand which was then added to the Au-NPs to form a supramolecular assembly on their surface. The Au-NPs modified in this way undergo aggregation in the presence of Pb(II) ions, and this causes the color to change from red to blue. The Pb(II)-induced aggregation can be monitored by using UV-visible spectrometry and even with the bare eye. The absorbance ratio (A 650nm /A 520nm ) is linearly related to the concentration of Pb(II) in the 0.1 to 75 μM range (with a correlation coefficient of 0.9957), and the detection limit is 50 nM which is lower than the allowable level (75 nM) as defined by the US EPA. The method was successfully applied to the determination of Pb(II) in spiked water samples. (author)

Crystal structure of 1-[(2S*,4R*-6-fluoro-2-methyl-1,2,3,4-tetrahydroquinolin-4-yl]pyrrolidin-2-one

Directory of Open Access Journals (Sweden)

P. S. Pradeep

2014-09-01

Full Text Available In the title compound, C14H17FN2O, the 1,2,3,4-tetrahydropyridine ring of the quinoline moiety adopts a half-chair conformation, while the pyrrolidine ring has an envelope conformation with the central methylene C atom as the flap. The pyrrolidine ring lies in the equatorial plane and its mean plane is normal to the mean plane of the quinoline ring system, with a dihedral angle value of 88.37 (9°. The bridging N—C bond distance [1.349 (3 Å] is substantially shorter than the sum of the covalent radii (dcov: C—N = 1.47 Å and C=N = 1.27 Å, which indicates partial double-bond character for this bond, resulting in a certain degree of charge delocalization. In the crystal, molecules are linked by N—H...O and C—H...O hydrogen bonds, forming sheets lying parallel to (10-1. These two-dimensional networks are linked via C—H...F hydrogen bonds and C—H...π interactions, forming a three-dimensional structure.

Ligand-Enabled γ-C(sp3)–H Olefination of Amines: En Route to Pyrrolidines

Science.gov (United States)

Jiang, Heng; He, Jian; Liu, Tao

2016-01-01

Pd(II)-catalyzed olefination of γ-C(sp3)–H bonds of triflyl (Tf) and 4-nitrobenzenesulfonyl (Ns) protected amines is achieved. Subsequent aza-Wacker oxidative cyclization or conjugate addition of the olefinated intermediates provides a variety of C-2 alkylated pyrrolidines. Three pyridine- and quinoline-based ligands are developed to match different classes of amine substrates, demonstrating a rare example of ligand-enabled C(sp3)–H olefination reaction. The use of Ns protecting group to direct C(sp3)–H activation of alkyl amine is also a significant step towards practical C–H functionalizations of alkyl amines. PMID:26796676

Corn silk induces nitric oxide synthase in murine macrophages.

Science.gov (United States)

Kim, Kyung A; Choi, Sang Kyu; Choi, Hye Seon

2004-12-31

Corn silk has been purified as an anticoagulant previously and the active component is a polysaccharide with a molecular mass of 135 kDa. It activates murine macrophages to induce nitric oxide synthase (NOS) and generate substantial amounts of NO in time and dose-dependent manners. It was detectable first at 15 h after stimulation by corn silk, peaked at 24 h, and undetectable by 48 h. Induction of NOS is inhibited by pyrolidine dithiocarbamate (PDTC) and genistein, an inhibitor of nuclear factor kappa B (NF-kappaB) and tyrosine kinase, respectively, indicating that iNOS stimulated by corn silk is associated with tyrosine kinase and NF-kappaB signaling pathways. IkappaB-alpha degradation was detectible at 10 min, and the level was restored at 120 min after treatment of corn silk. Corn silk induced nuclear translocation of NF-kappaB by phosphorylation and degradation of IkappaB-alpha.

Time-resolved fluorescence study of exciplex formation in diastereomeric naproxen-pyrrolidine dyads.

Science.gov (United States)

Khramtsova, Ekaterina A; Plyusnin, Viktor F; Magin, Ilya M; Kruppa, Alexander I; Polyakov, Nikolay E; Leshina, Tatyana V; Nuin, Edurne; Marin, M Luisa; Miranda, Miguel A

2013-12-19

The influence of chirality on the elementary processes triggered by excitation of the (S,S)- and (R,S)- diastereoisomers of naproxen-pyrrolidine (NPX-Pyr) dyads has been studied by time-resolved fluorescence in acetonitrile-benzene mixtures. In these systems, the quenching of the (1)NPX*-Pyr singlet excited state occurs through electron transfer and exciplex formation. Fluorescence lifetimes and quantum yields revealed a significant difference (around 20%) between the (S,S)- and (R,S)- diastereomers. In addition, the quantum yields of exciplexes differed by a factor of 2 regardless of solvent polarity. This allows us to suggest a similar influence of the chiral centers on the local charge transfer resulting in exciplex and full charge separation that leads to ion-biradicals. A simplified scheme is proposed to estimate a set of rate constant values (k1-k5) for the elementary stages in each solvent system.

Evaluation of the influence of proline, hydroxyproline or pyrrolidine in the presence of sodium nitrite on N-nitrosamine formation when heating cured meat.

Science.gov (United States)

Drabik-Markiewicz, G; Dejaegher, B; De Mey, E; Impens, S; Kowalska, T; Paelinck, H; Vander Heyden, Y

2010-01-11

N-nitrosamines are meant to be probable or possible carcinogenic components, possibly formed out of a reaction between nitrite and N-containing substances such as amino acids and secondary amines. Nitrite is often used for processing meat products because of its colouring and antimicrobial properties. During this experimental setup, the influence of proline, hydroxyproline or pyrrolidine on N-nitrosamine formation in meat samples was evaluated. The N-nitrosamines concentrations were measured with gas chromatography-thermal energy analyzer. Only the concentrations of N-nitrosodimethylamine and N-nitrosopyrrolidine were found above the limit of detection in a number of tested experimental conditions. The concentration of these two N-nitrosamines was modelled as a function of temperature and nitrite concentration for different situations (presence or absence of added natural N-containing meat components). It could be concluded that proline and pyrrolidine promoted the formation of N-nitrosopyrrolidine. It could also be confirmed that the higher the temperature of the meat processing procedure and the higher the sodium nitrite amounts added, the higher were the yields of the respective N-nitrosamines.

Method of removing nitrogen monoxide from a nitrogen monoxide-containing gas using a water-soluble iron ion-dithiocarbamate, xanthate or thioxanthate

Science.gov (United States)

Liu, D. Kwok-Keung; Chang, Shih-Ger

1987-08-25

The present invention relates to a method of removing of nitrogen monoxide from a nitrogen monoxide-containing gas which method comprises contacting a nitrogen oxide-containing gas with an aqueous solution of water soluble organic compound-iron ion chelate complex. The NO absorption efficiency of ferrous urea-dithiocarbamate and ferrous diethanolamine-xanthate as a function of time, oxygen content and solution ph is presented. 3 figs., 1 tab.

Absorption, translocation and metabolism of polycarbamate, a dithiocarbamate fungicide, in kidney bean seedlings

International Nuclear Information System (INIS)

Kumagai, H.; Kiyohara, C.; Komiyama, S.; Guo, Y.; Hirose, S.; Ichikawa, Y.; Endo, J.; Ikari, H.

1991-01-01

Absorption, translocation and metabolism of dizinc bis (dimethyldithiocarbamate)-ethylenebis (dithiocarbamate), bisdithane, were studied in kidney bean seedlings with its ethylene- 14 C-labeled [E- 14 C] and dimethyl- 14 C-labeled [D- 14 C] compounds. Most of the radioactivity remained at the application sites when labeled bisdithanes were applied on the surface of the first-trifoliate leaves of the plants. A small amount of the radioactivity was absorbed through the treated leaves. Translocation of the radioactivity from the leaves treated with the labeled bisdithanes to other parts of the plant was very small. These results were supported by the autoradiographic observations. The radioactive metabolites obtained from [E- 14 C] bisdithane were identified as ethylenethiourea and ethyleneurea. Tetramethylthiuram monosulfide, tetramethylthiuram disulfide, thiazolidine-2-thione-4-carboxylic acid and 1-(dimethylthiocarbamoylthio)-β-glucoside were identified when [D- 14 C] bisdithane was used. (author)

Dispersive liquid-liquid microextraction combined with graphite furnace atomic absorption spectrometry

International Nuclear Information System (INIS)

Zeini Jahromi, Elham; Bidari, Araz; Assadi, Yaghoub; Milani Hosseini, Mohammad Reza; Jamali, Mohammad Reza

2007-01-01

Dispersive liquid-liquid microextraction (DLLME) technique was successfully used as a sample preparation method for graphite furnace atomic absorption spectrometry (GF AAS). In this extraction method, 500 μL methanol (disperser solvent) containing 34 μL carbon tetrachloride (extraction solvent) and 0.00010 g ammonium pyrrolidine dithiocarbamate (chelating agent) was rapidly injected by syringe into the water sample containing cadmium ions (interest analyte). Thereby, a cloudy solution formed. The cloudy state resulted from the formation of fine droplets of carbon tetrachloride, which have been dispersed, in bulk aqueous sample. At this stage, cadmium reacts with ammonium pyrrolidine dithiocarbamate, and therefore, hydrophobic complex forms which is extracted into the fine droplets of carbon tetrachloride. After centrifugation (2 min at 5000 rpm), these droplets were sedimented at the bottom of the conical test tube (25 ± 1 μL). Then a 20 μL of sedimented phase containing enriched analyte was determined by GF AAS. Some effective parameters on extraction and complex formation, such as extraction and disperser solvent type and their volume, extraction time, salt effect, pH and concentration of the chelating agent have been optimized. Under the optimum conditions, the enrichment factor 125 was obtained from only 5.00 mL of water sample. The calibration graph was linear in the rage of 2-20 ng L -1 with detection limit of 0.6 ng L -1 . The relative standard deviation (R.S.D.s) for ten replicate measurements of 20 ng L -1 of cadmium was 3.5%. The relative recoveries of cadmium in tap, sea and rivers water samples at spiking level of 5 and 10 ng L -1 are 108, 95, 87 and 98%, respectively. The characteristics of the proposed method have been compared with cloud point extraction (CPE), on-line liquid-liquid extraction, single drop microextraction (SDME), on-line solid phase extraction (SPE) and co-precipitation based on bibliographic data. Therefore, DLLME combined with

Determination of Manganese, Copper, Cadmium and Lead by FAAS after Solid-Phase Extraction of Their Phenylpiperazine Dithiocarbamate Complexes on Activated Carbon

OpenAIRE

CESUR, Hasan

2014-01-01

A solid-phase extraction method was developed for the pre-concentration of manganese, copper, cadmium and lead in water samples prior to their determination by flame atomic absorption spectrometry using phenylpiperazine dithiocarbamate as a new reagent. The optimum pre-concentration conditions have been investigated such as pH, volume of sample solution and the effects of some matrix elements. The obtained recovery was nearly 90 to 100, while the enrichment factor was 400 for metal s...

Synthesis, Characterization and Biological Studies of New Phenyltin(IV) Dithiocarbamate Compounds

International Nuclear Information System (INIS)

Amirah Faizah Abdul Muthalib; Ibrahim Baba; Nazlina Ibrahim

2015-01-01

Nine chlorophenyl tin(IV) dithiocarbamate compounds of general formula PhSnCl[S 2 CNR ' R '' ] 2 (R ' = CH 3 , C 2 H 5 , C 7 H 7 and R ' = C 2 H 5 , C 6 H 11 , iC 3 H 7 , C 7 H 7 ) were prepared in one pot reaction of various secondary amine, carbon disulphide and phenyltin(1V) trichloride with the ratio of 2:2:1. These compounds have been characterized by elemental analysis, infrared spectroscopy, ultraviolet spectroscopy, 1 H, 13 C NMR spectroscopy as well as single crystal X-ray crystallography. Data from X-ray crystallography showed that (C 6 H 5 )SnCl[S 2 CN(C 2 H 5 )(iC 3 H 7 )] 2 is six coordinated bonded with two chelating dithiocarbamate ligands in bidentate fashion, methyl-C and chloride atom thus form a distorted octahedral geometry. Five selected compounds, (C 6 H 5 )SnCl[S 2 CN(CH 3 )(C 2 H 5 )] 2 , (C 6 H 5 )SnCl[S 2 CN(CH 3 )(C 6 H 11 )] 2 , (C 6 H 5 )SnCl[S 2 CN(C 2 H 5 )(iC 3 H 7 )] 2 , (C 6 H 5 )SnCl[S 2 CN(C 7 H 7 )(iC 3 H 7 )] 2 and (C 6 H 5 )SnCl[S 2 CN(C 7 H 7 ) 2 ] 2 were screened for anticancer activity against Chang liver cells. These compounds were demonstrated no cytotoxic effect for all concentrations under the condition of the study with no IC 50 value. The minimum inhibitory concentration (MIC) and maximum bactericidal concentration (MBC) determinations for these five compounds used Escherichia coli and Pseudomonas aeruginosa as Gram negative bacteria together with Staphylococcus aureus and Staphylococcus epidermis as Gram positive bacteria. Compound (C 6 H 5 )SnCl[S 2 CN(CH 3 )(C 2 H 5 )] 2 was the most active compared to the other compounds by having the lowest MIC values of 1.25 mg/ mL and MBC value of 5.0 mg/ mL against E. Coli and S. Aureus bacteria. Compounds (C 6 H 5 )SnCl[S 2 CN(C 7 H 7 )(iC 3 H 7 )] 2 and (C 6 H 5 )SnCl[S 2 CN(C 7 H 7 ) 2 ] 2 that having a benzyl group showed their MIC and MBC values slightly higher compared to the other compounds againts certain bacteria indicating their low

Structurally related antitumor effects of flavanones in vitro and in vivo: involvement of caspase 3 activation, p21 gene expression, and reactive oxygen species production

International Nuclear Information System (INIS)

Shen, S.-C.; Ko, C.H.; Tseng, S.-W.; Tsai, S.-H.; Chen, Y.-C.

2004-01-01

Flavonoids exist extensively in plants and Chinese herbs, and several biological effects of flavonoids have been demonstrated. The antitumor effects in colorectal carcinoma cells (HT29, COLO205, and COLO320HSR) of eight flavanones including flavanone, 2'-OH flavanone, 4'-OH flavanone, 6-OH flavanone, 7-OH flavanone, naringenin, nargin, and taxifolin were investigated. Results of the MTT assay indicate that 2'-OH flavanone showed the most potent cytotoxic effect on these three cells, and cell death induced by 2'-OH flavanone was via the occurrence of DNA ladders, apoptotic bodies, and hypodiploid cells, all characteristics of apoptosis. Induction of caspase 3 protein processing and enzyme activity associated with cleavage of poly(ADP-ribose) polymerase (PARP) was identified in 2'-OH flavanone-treated cells, and a peptidyl inhibitor (Ac-DEVD-FMK) of caspase 3 attenuated the cytotoxicity of 2'-OH flavanone in COLO205 and HT-29 cells. Elevation of p21 (but not p53) and a decrease in Mcl-1 protein were found in 2'-OH flavanone-treated COLO205 and HT-29 cells. Elevation of intracellular reactive oxygen species (ROS) was detected in 2'-OH flavanone-treated cells by the 2',7'-dichlorodihydrofluorescein diacetate (DCHF-DA) assay, and ROS scavengers including 4,5-dihydro-1,3-benzene disulfonic acid (tiron), catalase, superoxide dismutase (SOD), and pyrrolidine dithiocarbamate (PDTC) suppressed the 2'-OH flavanone-induced cytotoxic effect. Subcutaneous injection of COLO205 induced tumor formation in nude mice, and 2'-OH flavanone showed a significant inhibitory effect on tumor formation. The appearance of apoptotic cells with H and E staining, and an increase in p21, but not p53, protein by immunohistochemistry were observed in tumor tissues under 2'-OH flavanone treatment. Primary tumor cells (COLO205-X) derived from a tumor specimen elicited by COLO205 were established, and 2'-OH flavanone showed an significant apoptotic effect in COLO205-X cells in accordance with the

Determination of Lead in Blood by Atomic Absorption Spectrophotometry1

Science.gov (United States)

Selander, Stig; Cramér, Kim

1968-01-01

Lead in blood was determined by atomic absorption spectrophotometry, using a wet ashing procedure and a procedure in which the proteins were precipitated with trichloroacetic acid. In both methods the lead was extracted into isobutylmethylketone before measurement, using ammonium pyrrolidine dithiocarbamate as chelator. The simpler precipitation procedure was shown to give results identical with those obtained with the ashing technique. In addition, blood specimens were examined by the precipitation method and by spectral analysis, which method includes wet ashing of the samples, with good agreement. All analyses were done on blood samples from `normal' persons or from lead-exposed workers, and no additions of inorganic lead were made. The relatively simple protein precipitation technique gave accurate results and is suitable for the large-scale control of lead-exposed workers. PMID:5663425

Determination of Acid Dissociation Constants (pKa) of Bicyclic Thiohydantoin-Pyrrolidine Compounds in 20% Ethanol-Water Hydroorganic Solvent

Science.gov (United States)

Nural, Yahya; Döndaş, H. Ali; Sarı, Hayati; Atabey, Hasan; Belveren, Samet; Gemili, Müge

2014-01-01

The acid dissociation constants of potential bioactive fused ring thiohydantoin-pyrrolidine compounds were determined by potentiometric titration in 20% (v/v) ethanol-water mixed at 25 ± 0.1°C, at an ionic background of 0.1 mol/L of NaCl using the HYPERQUAD computer program. Proton affinities of potential donor atoms of the ligands were calculated by AM1 and PM3 semiempiric methods. We found, potentiometrically, three different acid dissociation constants for 1a–f. We suggest that these acid dissociation constants are related to the carboxyl, enol, and amino groups. PMID:24799905

Dithiocarbamates are teratogenic to developing zebrafish through inhibition of lysyl oxidase activity

International Nuclear Information System (INIS)

Boxtel, Antonius L. van; Kamstra, Jorke H.; Fluitsma, Donna M.; Legler, Juliette

2010-01-01

Dithiocarbamates (DTCs) are a class of compounds that are extensively used in agriculture as pesticides. As such, humans and wildlife are undoubtedly exposed to these chemicals. Although DTCs are thought to be relatively safe due to their short half lives, it is well established that they are teratogenic to vertebrates, especially to fish. In zebrafish, these teratogenic effects are characterized by distorted notochord development and shortened anterior to posterior axis. DTCs are known copper (Cu) chelators but this does not fully explain the observed teratogenic effects. We show here that DTCs cause malformations in zebrafish that highly resemble teratogenic effects observed by direct inhibition of a group of cuproenzymes termed lysyl oxidases (LOX). Additionally, we demonstrate that partial knockdown of three LOX genes, lox, loxl1 and loxl5b, sensitizes the developing embryo to DTC exposure. Finally, we show that DTCs directly inhibit zebrafish LOX activity in an ex vivo amine oxidase assay. Taken together, these results provide the first evidence that DTC induced teratogenic effects are, at least in part, caused by direct inhibition of LOX activity.

Group 12 dithiocarbamate complexes: Synthesis, spectral studies and their use as precursors for metal sulfides nanoparticles and nanocomposites

Science.gov (United States)

Ajibade, Peter A.; Ejelonu, Benjamin C.

2013-09-01

Zn(II), Cd(II) and Hg(II) dithiocarbamate complexes have been synthesized and characterized by elemental analysis, thermogravimetric analysis, UV-Vis, FTIR, 1H- and 13C NMR spectroscopy. The complexes were thermolysed at 180 °C and used as single molecule precursors for the synthesis of HDA capped ZnS, CdS and HgS nanoparticles and polymethylmethacrylate (PMMA) nanocomposites. The optical and structural properties of the nanoparticles and nanocomposites were studied by UV-Vis, PL, XRD and SEM. The crystallites sizes of the nanoparticles varied between 3.03 and 23.45 nm. SEM and EDX analyses of the nanocomposites confirmed the presence of the nanoparticles in the polymer matrix.

Impact of pyrrolidine-bispyrrole DNA minor groove binding agents and chirality on global proteomic profile in Escherichia Coli.

Science.gov (United States)

Yang, Ya-Ting; Lin, Chun-Yu; Jeng, Jingyueh; Ong, Chi-Wi

2013-05-23

There is great interest in the design of small molecules that selectively target minor grooves of duplex DNA for controlling specific gene expression implicated in a disease. The design of chiral small molecules for rational drug design has attracted increasing attention due to the chirality of DNA. Yet, there is limited research on the chirality effect of minor groove binders on DNA interaction, especially at the protein expression level. This paper is an attempt to illustrate that DNA binding affinity might not provide a full picture on the biological activities. Drug interacting at the genomic level can be translated to the proteomic level. Here we have illustrated that although the chiral bispyrrole-pyrrolidine-oligoamides, PySSPy and PyRSPy, showed low binding affinity to DNA, their influence at the proteomic level is significant. More importantly, the chirality also plays a role. Two-dimensional proteomic profile to identify the differentially expressed protein in Escherichia coli DH5α (E coli DH5α) were investigated. E coli DH5α incubated with the chiral PySSPy and PyRSPy, diastereomeric at the pyrrolidine ring, showed differential expression of eighteen proteins as observed through two dimensional proteomic profiling. These eighteen proteins identified by MALDI_TOF/TOF MS include antioxidant defense, DNA protection, protein synthesis, chaperone, and stress response proteins. No statistically significant toxicity was observed at the tested drug concentrations as measured via MTT assay. The current results showed that the chiral PySSPy and PyRSPy impact on the proteomic profiling of E coli DH5α, implicating the importance of drug chirality on biological activities at the molecular level.

Technetium-99m spiperone dithiocarbamate: a potential radiopharmaceutical for dopamine receptor imaging with SPECT

Energy Technology Data Exchange (ETDEWEB)

Ballinger, J R; Gulenchyn, K Y; Hassan, M N [Ottawa Civic Hospital (Canada). Div. of Nuclear Medicine and Neurology; Ottawa Univ., ON (Canada))

1989-01-01

Spiperone dithiocarbamate (SPDC) was prepared by reacting spiperone with carbon disulfide followed by sodium hydroxide. SPDC was labelled with {sup 99m}Tc by reduction of pertechnetate with formamidine sulfinic acid or sodium pertechnetate with formamidine sulfinic acid or sodium dithionite at alkaline pH, resulting in {similar to} 40% incorporation of {sup 99m}Tc. The lipophilic complex was conveniently isolated at high specific activity and high radiochemical purity by extraction into dichloromethane, which was then evaporated and the residue was redissolved in a 1:3 mixture of ethanol and saline containing 0.1mg/ml gentisic acid. Biodistribution studies following i.p. injection in rats showed low uptake of radioactivity in the brain, but striatum/cortex and striatum/cerebellum ratios were reduced by pretreatment with haloperidol. This agent may allow imaging of dopamine D-2 receptors using single-photon emission computed tomography (SPECT). (author).

Reducing the bioavailability of cadmium in contaminated soil by dithiocarbamate chitosan as a new remediation.

Science.gov (United States)

Yin, Zheng; Cao, Jingjing; Li, Zhen; Qiu, Dong

2015-07-01

Dithiocarbamate chitosan (DTC-CTS) was used as a new amendment for remediation of cadmium (Cd)-contaminated soils to reduce the Cd bioavailability. Arabidopsis thaliana was chosen as a model plant to evaluate its efficiency. It was found that DTC-CTS could effectively improve the growth of A. thaliana. The amount of Cd up-taken by A. thaliana could be decreased by as much as 50% compared with that grown in untreated Cd-contaminated soil samples. The chlorophyll content and the aerial biomass of Arabidopsis also increased substantially and eventually returned to a level comparable to plants grown in non-contaminated soils, with the addition of DTC-CTS. These findings suggested that DTC-CTS amendment could be effective in immobilizing Cd and mitigating its accumulation in plants grown in Cd-contaminated soils, with potential application as an in situ remediation of Cd-polluted soils.

Synthesis and characterization of diphenyltin (IV) dithiocarbamate compounds

International Nuclear Information System (INIS)

Amirah Faizah Abdul Muthalib; Ibrahim Baba; Yang Farina; Mohd Wahid Samsudin

2011-01-01

Ten compounds of diphenyltin(IV) with N-dialkyl dithiocarbamate were successfully prepared using in situ methods. Elemental analysis data (C, H, N and S) showed an agreement with the general formula of (C 6 H 5 ) 2 Sn[S 2 CNR 1 R 2 ] (R 1 = CH 3 , C 2 H 5 , C 7 H 7 ; R 2 = C 2 H 5 , C 4 H 9 , C 6 H 1 1, iC 3 H 7 , C 7 H 7 ). The structures of these compounds have been examined by infrared spectroscopy, ultraviolet, 1 H, 13 C and 119 Sn NMR spectroscopy and X-ray crystallography. The infrared spectra of these compounds showed three important peaks for v(C...N), v(C...S) and v(C...S) bands that appeared in the region of 1474 -1499, 969 - 995 and 324 - 335 cm -1 respectively. Data for 13 C NMR spectroscopy showed an important peak in the region of 198 - 200 ppm that corresponded to the NCS 2 group. Single crystal X-ray diffraction studies showed (C 6 H 5 ) 2 Sn[S 2 CN(C 2 H 5 )(CH 3 )] 2 (1) is six coordinated and adopted a monoclinic system with space group C2/c, while (C 6 H 5 ) 2 SnCl[S 2 CN(C 7 H 7 )(iC 3 H 7 )] (2) is five coordinated, crystallized in monoclinic system with space group Pb 1 /n. Meanwhile, six coordinated (C 6 H 5 ) 2 Sn[S 2 CN(CH 3 )(iC 3 H 7 )] 2 (3) adopted a orthorhombic system with a space group Pbcn. (author)

3,3,4,4-Tetrafluoro-1-[2-(3,3,4,4-tetrafluoropyrrolidin-1-ylphenyl]pyrrolidine

Directory of Open Access Journals (Sweden)

Jin Wang

2011-09-01

Full Text Available The asymmetric unit of the title compound, C14H12F8N2, contains one tetrafluoropyrrolidine system and one half-molecule of benzene; the latter, together with a second heterocyclic unit, are completed by symmetry, with a twofold crystallographic axis crossing through both the middle of the bond between the C atoms bearing the heterocyclic rings and the opposite C—C bonds of the whole benzene molecule. The pyrrolidine ring shows an envelope conformation with the apex at the N atom. The dihedral angle between the least-squares plane of this ring and the benzene ring is 36.9 (5°. There are intramolecular C—H...N interactions generating S(6 ring motifs. In the crystal structure, the molecules are linked by C—H...F interactions, forming chains parallel to [010].

Dithiocarbamate Self-Assembled Monolayers as Efficient Surface Modifiers for Low Work Function Noble Metals

Energy Technology Data Exchange (ETDEWEB)

Meyer, Dominik; Schäfer, Tobias; Schulz, Philip; Jung, Sebastian; Rittich, Julia; Mokros, Daniel; Segger, Ingolf; Maercks, Franziska; Effertz, Christian; Mazzarello, Riccardo; Wuttig, Matthias

2016-09-06

Tuning the work function of the electrode is one of the crucial steps to improve charge extraction in organic electronic devices. Here, we show that N,N-dialkyl dithiocarbamates (DTC) can be effectively employed to produce low work function noble metal electrodes. Work functions between 3.1 and 3.5 eV are observed for all metals investigated (Cu, Ag, and Au). Ultraviolet photoemission spectroscopy (UPS) reveals a maximum decrease in work function by 2.1 eV as compared to the bare metal surface. Electronic structure calculations elucidate how the complex interplay between intrinsic dipoles and dipoles induced by bond formation generates such large work function shifts. Subsequently, we quantify the improvement in contact resistance of organic thin film transistor devices with DTC coated source and drain electrodes. These findings demonstrate that DTC molecules can be employed as universal surface modifiers to produce stable electrodes for electron injection in high performance hybrid organic optoelectronics.

Synthesis, spectral and thermal studies of pyridyl adducts of Zn(II) and Cd(II) dithiocarbamates, and their use as single source precursors for ZnS and CdS nanoparticles.

Science.gov (United States)

Onwudiwe, Damian C; Strydom, Christien A; Oluwafemi, Oluwatobi S; Hosten, Eric; Jordaan, Anine

2014-06-21

The synthesis, spectroscopic characterisation, and thermal studies of pyridyl adducts of Zn(II) and Cd(II) complexes of N-ethyl-N-phenyl dithiocarbamate, represented as [ZnL2py] and [CdL2py2], are reported. Single-crystal X-ray structural analysis of the Zn compound showed that it is five-coordinate with four sulphurs from dithiocarbamate and one nitrogen from pyridine in a distorted square pyramidal geometry. The thermogravimetric studies indicate that the zinc and cadmium compounds undergo fast weight loss, and the temperature at maximum rate of decomposition is at 277 °C and 265 °C respectively, to give the metal (Zn or Cd) sulphide residues. These compounds were used as single molecule precursors to produce nanocrystalline MS (M = Zn, Cd) after thermolysis in hexadecylamine. The morphological and optical properties of the resulting MS nanocrystallites were investigated using transmission electron microscopy (TEM), scanning electron microscopy (SEM), UV-Vis absorption and photoluminescence (PL) spectroscopy, and powdered X-ray diffraction (XRD). By varying the growth time, the temporal evolution of the optical properties and morphology of the nanocrystals were investigated.

N-methyl-3-pyrrolidines preparation by means of [3+2] dipoles cycloaddition reactions; Preparacion de N-metil-3-arilpirrolidinas mediante reacciones de cicloadicion dipolares [3+2

Energy Technology Data Exchange (ETDEWEB)

Negron, Guillermo [Universidad Autonoma Metropolitana-Azcapotzalco, Mexico, D.F. (Mexico); Fuentes, Aydee; Romero, Moises [Universidad Autonoma del Estado de Mexico, Toluca, Estado de Mexico (Mexico); Madrid, Gustavo; Cruz, Raymundo [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)

1999-08-01

The [3+2] cycloaddition reaction between azomethine ylide generated by deprotonation of trimethylamine N-oxide with LDA and various {alpha}-asarone derivatives to afford the corresponding pyrrolidines is described. [Spanish] Las reacciones de cicloadicion [3+2] entre iluros de azometino generados por accion del LDA sobre el N-oxido de trimetilamina y varios derivados de la {alpha}-asarona, permite la obtencion de las pirrolidinas correspondientes.

A new class of potential chloroquine-resistance reversal agents for Plasmodia: syntheses and biological evaluation of 1-(3'-diethylaminopropyl)-3-(substituted phenylmethylene)pyrrolidines.

Science.gov (United States)

Batra, S; Srivastava, P; Roy, K; Pandey, V C; Bhaduri, A P

2000-09-07

1-(3'-Diethylaminopropyl)-3-(substituted phenylmethylene)pyrrolidines were synthesized and evaluated for CQ-resistant reversal activity. In general the compounds of the series elicit better biological response than their phenylmethyl analogues. The most active compound 4b has been evaluated in vivo in detail, and the results are presented. The possible mode of action of the compounds of this series is by inhibition of the enzyme heme oxygenase, thereby increasing the levels of heme and hemozoin, which are lethal to the parasite.

Ethyl 4′-ethenyl-2′-oxo-4-phenyl-2-(3,4,5-trimethoxyphenylspiro[pyrrolidine-3,3′-indoline]-5-carboxylate monohydrate

Directory of Open Access Journals (Sweden)

P. Ramesh

2008-11-01

Full Text Available In the title compound, C31H32N2O6·H2O, the pyrrolidine ring adopts an envelope conformation. The ethyl C atoms of the ethoxycabonyl group are disordered over two positions with occupancies of ca 0.80 and 0.20. Intramolecular N—H...O hydrogen bonds form S(5 and S(6 ring motifs. Molecules are linked into a three-dimensional framework by O—H...O, N—H...O and C—H...O hydrogen bonds, and by C—H...π interactions.

Sulfur K-edge X-ray absorption spectroscopy and time-dependent density functional theory of arsenic dithiocarbamates.

Science.gov (United States)

Donahue, Courtney M; Pacheco, Juan S Lezama; Keith, Jason M; Daly, Scott R

2014-06-28

S K-edge X-ray absorption spectroscopy (XAS) and time-dependent density functional theory (TDDFT) calculations were performed on a series of As[S2CNR2]3 complexes, where R2 = Et2, (CH2)5 and Ph2, to determine how dithiocarbamate substituents attached to N affect As[S2CNR2]3 electronic structure. Complimentary [PPh4][S2CNR2] salts were also studied to compare dithiocarbamate bonding in the absence of As. The XAS results indicate that changing the orientation of the alkyl substituents from trans to cis (R2 = Et2vs. (CH2)5) yields subtle variations whereas differences associated with a change from alkyl to aryl are much more pronounced. For example, despite the differences in As 4p mixing, the first features in the S K-edge XAS spectra of [PPh4][S2CNPh2] and As[S2CNPh2]3 were both shifted by 0.3 eV compared to their alkyl-substituted derivatives. DFT calculations revealed that the unique shift observed for [PPh4][S2CNPh2] is due to phenyl-induced splitting of the π* orbitals delocalized over N, C and S. A similar phenomenon accounts for the shift observed for As[S2CNPh2]3, but the presence of two unique S environments (As-S and As···S) prevented reliable analysis of As-S covalency from the XAS data. In the absence of experimental values, DFT calculations revealed a decrease in As-S orbital mixing in As[S2CNPh2]3 that stems from a redistribution of electron density to S atoms participating in weaker As···S interactions. Simulated spectra obtained from TDDFT calculations reproduce the experimental differences in the S K-edge XAS data, which suggests that the theory is accurately modeling the experimental differences in As-S orbital mixing. The results highlight how S K-edge XAS and DFT can be used cooperatively to understand the electronic structure of low symmetry coordination complexes containing S atoms in different chemical environments.

Functionalized dithiocarbamate chelating resin for the removal of Co2+ from simulated wastewater

Science.gov (United States)

Shi, Xuewei; Fu, Linwei; Wu, Yanyang; Zhao, Huiling; Zhao, Shuangliang; Xu, Shouhong

2017-12-01

Industrial wastewater that contains trace amounts of heavy metal ions is often seen in petrochemical industry. While this wastewater can not be directly discharged, it is difficult to treat due to the low concentration of metal ions. Introducing chelating reagents into this wastewater for selective ion adsorption, followed by a mechanical separation process, provides an appealing solution. Toward the success of this technology, the development of effective chelating resins is of key importance. In the present work, a chelating resin containing amino and dithiocarbamate groups was reported for the removal of Co(II) metal ions in trace concentrations from simulated wastewater. By investigating the adsorption performance of the chelating resin at different solution pH values, adsorbent dosages, contact time, initial ion concentrations, and adsorption temperatures, the maximum adsorption capacity of the resin for Co(II) was identified to be 24.89 mg g-1 for a 2 g L-1 adsorbent dosage and a pH value of 5. After four adsorption-desorption cycles, 97% of the adsorption capacity of the resin was maintained. The adsorption kinetics and thermodynamics were analyzed and discussed as well.

Inhibitors of nuclear factor kappa B cause apoptosis in cultured macrophages

Directory of Open Access Journals (Sweden)

E. E. Mannick

1997-01-01

Full Text Available The precise role of the transcription factor nuclear factor kappa B (NF- κB in the regulation of cell survival and cell death is still unresolved and may depend on cell type and position in the cell cycle. The aim of this study was to determine if three pharmacologic inhibitors of NF-κB, pyrrolidine dithiocarbamate, N-tosyl-L-lysl chloromethyl ketone and calpain I inhibitor, induce apoptosis in a murine macrophage cell line (RAW 264.7 at doses similar to those required for NF-κB inhibition. We found that each of the three inhibitors resulted in a dose- and time-dependent increase in morphologic indices of apoptosis in unstimulated, LPS-stimulated and TNF-stimulated cells. Lethal doses were consistent with those required for NF- κB inhibition. We conclude that nuclear NF-κB activation may represent an important survival mechanism in macrophages.

Separation/preconcentration of silver(I) and lead(II) in environmental samples on cellulose nitrate membrane filter prior to their flame atomic absorption spectrometric determinations

International Nuclear Information System (INIS)

Soylak, Mustafa; Cay, Rukiye Sungur

2007-01-01

An enrichment method for trace amounts of Ag(I) and Pb(II) has been established prior to their flame atomic absorption spectrometric determinations. The preconcentration/separation procedure is based on chelate formation of Ag(I) and Pb(II) with ammonium pyrrolidine dithiocarbamate (APDC) and on retention of the chelates on cellulose nitrate membrane filter. The influences of some analytical parameters including pH and amounts of reagent, etc. on the recoveries of analytes were investigated. The effects of interferic ions on the quantitative recoveries of analytes were also examined. The detection limits (k = 3, N = 11) were 4.6 μg L -1 for silver(I) and 15.3 μg L -1 for lead(II). The relative standard deviations (R.S.D.) of the determinations for analyte ions were below 3%. The method was applied to environmental samples for the determination of analyte ions with satisfactory results (recoveries >95%)

Atomic absorption spectrophotometric determination of microgram levels of Co, Ni, Cu, Pb, and Zn in soil and sediment extracts containing large amounts of Mn and Fe

Science.gov (United States)

Chao, T.T.; Sanzolone, R.F.

1973-01-01

An atomic absorption spectrophotometric method has been developed for the determination of seven metal ions in the hydroxylamine extract of soils and sediments. Mn, Fe, and Zn are directly determined in the aqueous extract upon dilution. Co, Ni, Cu, and Pb in a separate aliquot of the extract are chelated with APDC (ammonium pyrrolidine dithiocarbamate) and extracted into MIBK (methyl isobutyl ketone) before determination. Data are presented to show the quantitative recovery of microgram levels of Co, Ni, Cu, and Pb by APDC-MIBK chelation-extraction from synthetic solutions containing as much as 2,000 ug/ml (micrograms per milliliter) Mn or 50 ug/ml Fe. Recovery of known amounts of the metal ions from sample solutions is equally satisfactory. Reproducible results are obtained by replicate analyses of two sediment samples for the seven metals.

Spiperone dithiocarbamate- 99mTc kit - a potential diagnosis agent for dopaminergic D-2 brain pathologies - biodistribution

International Nuclear Information System (INIS)

Goncalves, M.M.

1993-01-01

Psycho pharmacology has been discovering much about the D 2 dopamine receptors and their interrelationship to brain pathologies such as Parkinson's Disease, Schizophrenia and Huntington Disease. Those biological receptors have got affinity with dopamine endogenous agent, so that they complex and, in non pathological individuals, the biological receptors contribute to bring the levels of dopamine and free acetylcholine into equilibrium. The Spiperon Dithiocarbamate (SPDC) from Spiperon is synthesized and its complexation with Technetium-99 m has been prepared with its reaction parameters after being studied and improved. The SPDC- 99m Tc complex biological distribution has been made in Wistar rats and the uptake of spleen, heart, liver, stomach, lung, kidney, blood, intestine and brain have been resolved. The plasmatic clearance curve has been based on Wistar rats data and the Know-how of the kit ( for label SPDC with 99m Tc) has been achieved. (author)

Syntheses and study of pyrrolidinic nitroxide free radicals. Preparation of a nitroxide-type stable bi-radical; Synthese et etudes de radicaux libres nitroxydes pyrrolidiniques. Preparation d'un biradical stable du type nitroxyde

Energy Technology Data Exchange (ETDEWEB)

Dupeyre, R M [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires, Laboratoire de chimie organique physique

1967-12-01

Syntheses and study of pyrrolidinic nitroxide free radicals: These radicals are obtained by oxidation, with hydrogen peroxide, of pyrrolidinic amines prepared from triacetonamine by ring contraction. The U. V,, I. R, and E.P.R. spectral characteristics have been determined. The oxidation of these amines with hydrogen peroxide has led also to rupture of the pentagonal ring; some of the decomposition products have been identified. The high chemical stability of the nitroxide group has made it possible to synthesize and study a stable bi-radical. (author) [French] Syntheses et etudes de radicaux libres nitroxydes pyrrolidiniques: Ces radicaux sont obtenus par oxydation l'eau oxygenee d'amines pyrrolidiniques preparees a partir de la triacetonamine par contraction de cycle. Les caracteristiques spectroscopiques ultra-violettes, infra-rouge et resonance paramagnetique sont determinees. Cependant, 1'oxydation de ces amines a l'eau oxygenee a entraine la coupure du cycle pentagonal et identification de certaines substances de decomposition obtenues. La grande stabilite chimique de groupement nitroxyde a permis la synthese et l'etude d'un biradical stable. (auteur)

Synthesis, characterization and anticancer activity of gold(I) complexes that contain tri-tert-butylphosphine and dialkyl dithiocarbamate ligands

KAUST Repository

Altaf, Muhammad

2015-03-10

Two new gold(I) complexes that contain tri-ter-butylphosphine and dialkyl dithiocarbamate ligands were synthesized and characterized by FTIR, NMR spectroscopy, Cyclic voltammetry, elemental analysis and X-ray diffraction. The in vitro cytotoxicity of both complexes was examined against A549 (lung cancer), MCF7 (breast cancer), and HeLa (cervical cancer) human cancer cell lines. Both complexes exhibit very strong in vitro cytotoxic effects against A549, MCF7 and HeLa cell lines. The screening of the cytotoxic activity based on IC50 data against the A549, MCF7, and HeLa lines shows that the synthesized gold(I) complexes are highly effective, particularly against HeLa cancer cell line. Based on IC50 data, the cytotoxic activity of both complexes is better than well-known commercial anticancer drug cisplatin against all the three cancer lines tested.

First organic–inorganic hybrid nanomaterial constructed from a Keggin-type polyoxometallate and a copper-dithiocarbamate complex: sonochemical synthesis, crystal structure and its adsorption performance for organic dye pollutants

Czech Academy of Sciences Publication Activity Database

Farhadi, S.; Dušek, Michal; Siadatnasab, F.; Eigner, Václav; Mokhtari Andani, A.

2017-01-01

Roč. 126, Apr (2017), s. 227-238 ISSN 0277-5387 R&D Projects: GA ČR(CZ) GA15-12653S; GA MŠk LO1603 EU Projects: European Commission(XE) CZ.2.16/3.1.00/24510 Institutional support: RVO:68378271 Keywords : organic–inorganic hybrid * polyoxometallate * dithiocarbamate * adsorption * organic dye pollutants Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 1.926, year: 2016

Sb(III) and Sb(V) separation and analytical speciation by a continuous tandem on-line separation device in connection with inductively coupled plasma atomic emission spectrometry

Energy Technology Data Exchange (ETDEWEB)

Menendez Garcia, A. [Oviedo Univ. (Spain). Dept. of Phys. and Anal. Chem.; Perez Rodriguez, M.C. [Oviedo Univ. (Spain). Dept. of Phys. and Anal. Chem.; Sanchez Uria, J.F. [Oviedo Univ. (Spain). Dept. of Phys. and Anal. Chem.; Sanz-Medel, A. [Oviedo Univ. (Spain). Dept. of Phys. and Anal. Chem.

1995-09-01

A sensitive, precise and automated non-chromatographic method for Sb(III) and Sb(V) analytical speciation based on a continuous tandem on-line separation device in connection with inductively coupled plasma-atomic emission (ICP-AES) detection is proposed. Two on-line successive separation steps are included into this method: a continuous liquid-liquid extraction of Sb(III) with ammonium pyrrolidine dithiocarbamate (APDC) into methylisobuthylketone (MIBK), followed by direct stibine generation from the organic phase. Both separation steps are carried out in a continuous mode and on-line with the ICP-AES detector. Optimization of experimental conditions for the tandem separation and ICP-AES detection are investigated in detail. Detection limits for Sb(III) were 3 ng.mL{sup -1} and for Sb(V) 8 ng.mL{sup -1}. Precisions observed are in the range {+-} 5%. The proposed methodology has been applied to Sb(III) and Sb(V) speciation in sea-water samples. (orig.)

Icotinib inhibits the invasion of Tca8113 cells via downregulation of nuclear factor κB-mediated matrix metalloproteinase expression.

Science.gov (United States)

Yang, Cailing; Yan, Jianguo; Yuan, Guoyan; Zhang, Yinghua; Lu, Derong; Ren, Mingxin; Cui, Weigang

2014-09-01

Icotinib is an epidermal growth factor receptor tyrosine kinase inhibitor, which has been revealed to inhibit proliferation in tumor cells. However, the effect of icotinib on cancer cell metastasis remains to be explained. This study examines the effect of icotinib on the migration and invasion of squamous cells of tongue carcinoma (Tca8113 cells) in vitro . The results of the Boyden chamber invasion assay demonstrated that icotinib reduced cell invasion, suppressed the protein levels of matrix metalloproteinases (MMPs), MMP-2 and MMP-9, and increased the expression of tissue inhibitor of metalloproteinase-1. In addition, icotinib was found to significantly decrease the protein levels of nuclear factor κB (NF-κB) p65, which suggested that icotinib inhibits NF-κB activity. Furthermore, treatment with the NF-κB inhibitor, pyrrolidine dithiocarbamate, suppressed cell invasion and MMP-2 expression. These results suggested that icotinib inhibits the invasion of Tca8113 cells by downregulating MMP via the inactivation of the NF-κB signaling pathways.

Ultratrace Determination of Cr(VI and Pb(II by Microsample Injection System Flame Atomic Spectroscopy in Drinking Water and Treated and Untreated Industrial Effluents

Directory of Open Access Journals (Sweden)

Jameel Ahmed Baig

2013-01-01

Full Text Available Simple and robust analytical procedures were developed for hexavalent chromium (Cr(VI and lead (Pb(II by dispersive liquid-liquid microextraction (DLLME using microsample injection system coupled with flame atomic absorption spectrophotometry (MIS-FAAS. For the current study, ammonium pyrrolidine dithiocarbamate (APDC, carbon tetrachloride, and ethanol were used as chelating agent, extraction solvent, and disperser solvent, respectively. The effective variables of developed method have been optimized and studied in detail. The limit of detection of Cr(VI and Pb(II were 0.037 and 0.054 µg/L, respectively. The enrichment factors in both cases were 400 with 40 mL of initial volumes. The relative standard deviations (RSDs, were 96%. The proposed method was successfully applied to the determination of Cr(VI and Pb(II at ultratrace levels in natural drinking water and industrial effluents wastewater of Denizli. Moreover, the proposed method was compared with the literature reported method.

Synthesis of a new series of dithiocarbamates with effective human carbonic anhydrase inhibitory activity and antiglaucoma action.

Science.gov (United States)

Bozdag, Murat; Carta, Fabrizio; Vullo, Daniela; Akdemir, Atilla; Isik, Semra; Lanzi, Cecilia; Scozzafava, Andrea; Masini, Emanuela; Supuran, Claudiu T

2015-05-15

A new series of dithiocarbamates (DTCs) was prepared from primary/secondary amines incorporating amino/hydroxyl-alkyl, mono- and bicyclic aliphatic ring systems based on the quinuclidine, piperidine, hydroxy-/carboxy-/amino-substituted piperidine, morpholine and piperazine scaffolds, and carbon disulfide. The compounds were investigated for the inhibition of four mammalian α-carbonic anhydrases (CAs, EC 4.2.1.1) of pharmacologic relevance, that is, the human (h) hCA I, II, IX and XII, drug targets for antiglaucoma (hCA II and XII) or antitumor (hCA IX/XII) agents. The compounds were moderate or inefficient hCA I inhibitors (off-target isoform for both applications), efficiently inhibited hCA II, whereas some of them were low nanomolar/subnanomolar hCA IX/XII inhibitors. One DTC showed excellent intraocular pressure (IOP) lowering properties in an animal model of glaucoma, with a two times better efficiency compared to the clinically used sulfonamide dorzolamide. Copyright © 2015 Elsevier Ltd. All rights reserved.

Synthesis and biodistribution of a novel 99mTc nitrido dithiocarbamate complex containing aromatic group for cerebral imaging

International Nuclear Information System (INIS)

Zhang Junbo; Lin Xiao; Ren Jialei; Liu Jing; Wang Xuebin

2010-01-01

In the present study, the N-benzyl dithiocarbamate (BZDTC) was synthesized and radiolabeled with [ 99m TcN] 2+ intermediate to form the bis(N-benzyl dithiocarbamato) nitrido technetium-99m complex [ 99m TcN(BZDTC) 2 ]. The radiochemical purity of the complex was over 90% by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). It was stable over 6 h at room temperature. The partition coefficient and electrophoresis results indicated that this complex was lipophilic and neutral. Biodistribution in mice showed that the complex accumulated in the brain with high uptake. The brain uptake (ID%/g) was 1.87, 1.21 and 0.85 and the brain/blood ratio was 0.75, 1.55 and 1.12 at 5, 30 and 60 min post-injection, respectively. These results suggest that this complex could be a potential brain perfusion imaging agent.

Thermal Studies of Zn(II, Cd(II and Hg(II Complexes of Some N-Alkyl-N-Phenyl-Dithiocarbamates

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Peter A. Ajibade

2012-07-01

Full Text Available The thermal decomposition of Zn(II, Cd(II and Hg(II complexes of N-ethyl-N-phenyl and N-butyl-N-phenyl dithiocarbamates have been studied using thermogravimetric analysis (TGA and differential scanning calorimetry (DSC. The products of the decomposition, at two different temperatures, were further characterized by scanning electron microscopy (SEM and energy-dispersive X-ray spectroscopy (EDX. The results show that while the zinc and cadmium complexes undergo decomposition to form metal sulphides, and further undergo oxidation forming metal oxides as final products, the mercury complexes gave unstable volatiles as the final product.

A review of methods for the analysis of orphan and difficult pesticides: glyphosate, glufosinate, quaternary ammonium and phenoxy acid herbicides, and dithiocarbamate and phthalimide fungicides.

Science.gov (United States)

Raina-Fulton, Renata

2014-01-01

This article reviews the chromatography/MS methodologies for analysis of pesticide residues of orphan and difficult chemical classes in a variety of sample matrixes including water, urine, blood, and food. The review focuses on pesticide classes that are not commonly included in multiresidue analysis methods such as highly polar or ionic herbicides including glyphosate, glufosinate, quaternary ammonium, and phenoxy acid herbicides, and some of their major degradation or metabolite products. In addition, dithiocarbamate and phthalimide fungicides, which are thermally unstable and have stability issues in some solvents or sample matrixes, are also examined due to their special needs in residue analysis.

Evidence of active transport of cadmium complexing dithiocarbamates into renal and hepatic cells in vivo

International Nuclear Information System (INIS)

Gale, G.R.; Smith, A.B.; Jones, M.M.; Singh, P.K.

1992-01-01

A study was made of the effects of certain inhibitors of transport systems on the actions of four cadmium (Cd) complexing N,N-disubstituted dithiocarbamates (DTCs) in mobilizing murine renal and hepatic Cd in vivo. Probenecid, the prototypical antagonist of organic anion transport in the kidney, when given 1 hr prior to each DTC, sharply suppressed the DTC-induced reduction of renal Cd but was virtually without effect on mobilization of Cd from liver. Sulfinpyrazone, which blocks tubular reabsorption of uric acid and also inhibits transport of a variety of organic acids, inhibited markedly the mobilization of both renal and hepatic Cd by DTCs. Phlorizin, an inhibitor of tubular sugar reabsorption, did not affect the Cd mobilizing actions of DTCs in any consistent fashion. We propose that the high degree of selectivity of DTCs in mobilizing renal hepatic Cd is dependent, at lest in part, upon active transport of DTCs into these tissues via the organic anion transport systems. This report presents the first evidence that compounds of the (R) 2 NCSS - class may gain access to intracellular space by an active, carrier-mediated process. (au)

Adsorption performances and mechanisms of the newly synthesized N,N'-di (carboxymethyl) dithiocarbamate chelating resin toward divalent heavy metal ions from aqueous media

International Nuclear Information System (INIS)

Jing Xiaosheng; Liu Fuqiang; Yang Xin; Ling Panpan; Li Lanjuan; Long Chao; Li Aimin

2009-01-01

N,N'-di (carboxymethyl) dithiocarbamate chelating resin (PSDC) was synthesized by anchoring the chelating agent of N,N'-di (carboxymethyl) dithiocarbamate to the chloromethylated PS-DVB (Cl-PS-DVB) matrix, as a new adsorbent for removing divalent heavy metal ions from waste-stream. The physicochemical structures of Cl-PS-DVB and PSDC were elaborately characterized using Fourier transform infrared spectroscopy (FT-IR), elemental analysis (EA), and were further morphologically characterized using BET and BJH methods. The adsorption performances of PSDC towards heavy metals such as Cu(II), Pb(II) and Ni(II) were systematically investigated, based upon which the adsorption mechanisms were deeply exploited. For the above target, the classic batch adsorption experiments were conducted to explore the kinetics and isotherms of the removal processes with pH-value, initial concentration, temperature, and contact time as the controlling parameters. The kinetic and isotherm data could be well elucidated with Lagergren-second-order equation and Langmuir model respectively. The strong affinity of PSDC toward these target soft acids could be well demonstrated with the electrostatic attraction and chelating interaction caused by IDA moiety and sulphur which were namely soft bases on the concept of hard and soft acids and bases (HASB). Thermodynamic parameters, involving ΔH o , ΔS o and ΔG o were also calculated from graphical interpretation of the experimental data. The standard heats of adsorption (ΔH o ) were found to be endothermic and the entropy change values (ΔS o ) were calculated to be positive for the adsorption of Cu(II), Pb(II) and Ni(II) ions onto the tested adsorbents. Negative values of ΔG o indicated that adsorption processes for all tested metal ions onto PSDC were spontaneous.

Poorly Differentiated Thyroid Carcinoma.

Science.gov (United States)

Setia, Namrata; Barletta, Justine A

2014-12-01

Poorly differentiated thyroid carcinoma (PDTC) has been recognized for the past 30 years as an entity showing intermediate differentiation and clinical behavior between well-differentiated thyroid carcinomas (ie, papillary thyroid carcinoma and follicular thyroid carcinoma) and anaplastic thyroid carcinoma; however, there has been considerable controversy around the definition of PDTC. In this review, the evolution in the definition of PDTC, current diagnostic criteria, differential diagnoses, potentially helpful immunohistochemical studies, and molecular alterations are discussed with the aim of highlighting where the diagnosis of PDTC currently stands. Published by Elsevier Inc.

Discovery of a New Class of Ionotropic Glutamate Receptor Antagonists by the Rational Design of (2S,3R)-3-(3-Carboxyphenyl)-pyrrolidine-2-carboxylic Acid

DEFF Research Database (Denmark)

Larsen, Ann Møller; Venskutonyte, Raminta; Valadés, Elena Antón

2011-01-01

The kainic acid (KA) receptors belong to the class of glutamate (Glu) receptors in the brain and constitute a promising target for the treatment of neurological and/ or psychiatric diseases such as schizophrenia, major depression, and epilepsy. Five KA subtypes have been identified and named GluK1......-5. In this article, we present the discovery of (2S,3R)-3-(3-carboxyphenyl)-pyrrolidine-2-carboxylic acid (1) based on a rational design process. Target compound 1 was synthesized by a stereoselective strategy in 10 steps from commercially available starting materials. Binding affinities of 1 at native ionotropic...

Clinical features and prognostic factors for survival in patients with poorly differentiated thyroid carcinoma and comparison to the patients with the aggressive variants of papillary thyroid carcinoma

International Nuclear Information System (INIS)

Jung, Tae-Sik; Kim, Tae-Yong; Kim, Kyung-Won

2007-01-01

We performed this study to compare the clinicopathologic features and outcomes between the patients with poorly differentiated thyroid carcinoma (PDTC) and the patients with the aggressive variants of papillary thyroid carcinoma (PTC). To evaluate the prognostic factors for survival of the patients with PDTC, we selected 49 patients with PDTC and 23 patients with the aggressive variants of PTC from three hospitals during the recent 15 years. The five-year survival rate and clinicopathologic features of the patients with PDTC were not different from those of the patients with the aggressive variants of PTC. Univariate analysis revealed the significant poor prognostic factors for survival of the patients with PDTC and the aggressive variants of PTC as follows: an age more than 45 years, a tumor size larger than 4 cm, the presence of tumor invasion to extrathyroidal tissue or the trachea, the presence of cervical lymph node invasion, the presence of distant metastasis, the absence of high-dose radioactive iodine (RAI) therapy, and tumor, nodes and metastasis (TNM) stage II, III and IV. Distant metastasis and high-dose RAI therapy were independent significant predictors for survival of the patients with PDTC and the aggressive variants of PTC on multivariate analysis. However, distant metastasis was the only independent significant predictors for survival of the patients with PDTC excluding patients with the aggressive variants of PTC. (author)

Synthesis, Structural and Antibacterial Studies of New Dithiocarbamate Complexes of Sb (III) And Bi (III)

International Nuclear Information System (INIS)

Nur Amirah Jamaluddin; Ibrahim Baba; Nazlina Ibrahim

2014-01-01

Six new dithiocarbamate complexes from three different amines, for example N-ethyl ethanol-, N-butylethyl- and N-benzylmethylamine were successfully prepared using in situ method. All complexes were characterized by elemental analysis, IR, UV-Vis, 13 C and 1 H NMR. Elemental analysis data (C, H, N and S) showed an agreement with the general formula of MCl(S 2 CNR ' R '' ) 2 , (M = Sb (III), Bi (III); R ' = ethyl, butyl and benzyl; R '' = ethanol, ethyl and methyl). The complexes had been characterized by infrared spectroscopy that showed a thioureido bands, v(C-N) in the region of 1427 - 1490 cm -1 followed by v(C-S) bands that can be seen in the region of 935 - 1060 cm -1 and v(M-S) bands existed in the region of 350 - 392 cm -1 . Maximum wavelength absorption for ultraviolet-visible spectroscopy for N-C-S group was at 254 nm which indicates π → π * transition. Data from 13 C NMR showed a signal in the region of 198.39 - 199.44 ppm that corresponded to the NCS 2 group. The crystal structure of bis(N,N ' utylethyldithiocarbamato)chloride antimony (III), SbCl (S 2 CN(C 4 H 9 )(C 2 H 5 )) 2 demonstrated a five-coordination geometry, triclinic system, space group P1 with a = 10.0141(8) Armstrong, b = 10.1394(7) Am strong, c = 11.8665(9) Armstrong, α = 67.960(2) degree, β = 87.616(2) degree and γ = 80.172(2) degree. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests were done using five dithiocarbamate complexes which are Bi Cl[S 2 CN(C 2 H 5 )(C 2 H 4 OH)) 2 , SbCl[S 2 CN(C 2 H 5 )(C 2 H 4 OH)) 2 , Bi Cl(S 2 CN(C 4 H 9 )(C 2 H 5 )) 2 , SbCl(S 2 CN(C 4 H 9 )(C 2 H 5 )) 2 , Bi Cl(S 2 CN(C 7 H 7 )(CH 3 )) 2 towards S. aureus, S. epidermidis, E. aerogenes and E. coli. It was found that all four complexes were active against S. aureus except SbCl(S 2 CN(C 2 H 5 )(C 2 H 4 OH)) 2 while Bi Cl(S 2 CN(C 7 H 7 )(CH 3 )) 2 and Bi Cl(S 2 CN(CH 3 )(C 6 H 11 )) 2 complexes were active against S. epidermidis with MIC value of 5.0 mg/ m

Synthesis, Crystal Structure, and Electroconducting Properties of a 1D Mixed-Valence Cu(I–Cu(II Coordination Polymer with a Dicyclohexyl Dithiocarbamate Ligand

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Kenji Nakatani

2015-04-01

Full Text Available A new mixed-valence Cu(I–Cu(II 1D coordination polymer, [CuI4CuIIBr4(Cy2dtc2]n, with an infinite chain structure is synthesized by the reaction of Cu(Cy2dtc2 (Cy2dtc− = dicyclohexyl dithiocarbamate, C13H22NS2 with CuBr·S(CH32. The as-synthesized polymer consists of mononuclear copper(II units of CuII(Cy2dtc2 and tetranuclear copper(I cluster units, CuI4Br4. In the cluster unit, all the CuI ions have distorted trigonal pyramidal coordination geometries, and the CuI–CuI or CuI–CuII distances between the nearest copper ions are shorter than the sum of van der Waals radii for Cu–Cu.

Analysis of Dithiocarbamate Fungicides in Vegetable Matrices Using HPLC-UV Followed by Atomic Absorption Spectrometry.

Science.gov (United States)

Al-Alam, Josephine; Bom, Laura; Chbani, Asma; Fajloun, Ziad; Millet, Maurice

2017-04-01

A simple method combining ion-pair methylation, high-performance liquid chromatography (HPLC) analysis with detection at 272 nm and atomic absorption spectrometry was developed in order to determine 10 dithiocarbamate fungicides (Dazomet, Metam-sodium, Ferbam, Ziram, Zineb, Maneb, Mancozeb, Metiram, Nabam and Propineb) and distinguish ethylenbisdithiocarbamates (EBDTCs) Zineb, Maneb and Mancozeb in diverse matrices. This method associates reverse phase analysis by HPLC analysis with detection at 272 nm, with atomic absorption spectrometry in order to distinguish, with the same extraction protocol, Maneb, Mancozeb and Zineb. The limits of detection (0.4, 0.8, 0.5, 1.25 and 1.97) and quantification (1.18, 2.5, 1.52, 4.2 and 6.52) calculated in injected nanogram, respectively, for Dazomet, Metam-Na, dimethyldithiocarbamates (DMDTCs), EBDTCs and propylenebisdithiocarbamates (PBDTCs) justify the sensitivity of the method used. The coefficients of determination R2 were 0.9985, 0.9978, 0.9949, 0.988 and 0.9794, respectively, for Dazomet, Metam-Na, DMDTCs, EBDTCs and PBDTCs, and the recovery from fortified apple and leek samples was above 90%. Results obtained with the atomic absorption method in comparison with spectrophotometric analysis focus on the importance of the atomic absorption as a complementary specific method for the distinction between different EBDTCs fungicides. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Preconcentration of trace manganese from natural waters by complexation with dithiocarbamate and adsorption onto C18-solid phase extraction column for neutron activation analysis

International Nuclear Information System (INIS)

Sarmani, S.B.; Abdullah, M.P.; Bobaker, A.M.

2004-01-01

A method was developed for the preconcentration and separation of trace manganese from natural water samples by complexation with dithiocarbamate followed by adsorption onto C 18 -solid phase extraction column prior to irradiation. The Mn recovery was better than 99.8% without interference from iron(III) at 5 mg x l -1 , copper(II), zinc(II), aluminum(III) and cobalt(II) at 0.5 mg x l -1 and sodium(I), potassium(I), magnesium(II) and calcium(II) at 1 mg x l -1 . The separation factor was 100 and the detection limit was 0.01 μg x l -1 with good precision and accuracy with a relative error lower than 3%. The method was applied to the determination of Mn in tap, well, river and treated water samples. (author)

Design and Synthesis of a Series of L-trans-4-Substituted Prolines as Selective Antagonists for the Ionotropic Glutamate Receptors Including Functional and X-ray Crystallographic Studies of New Subtype Selective Kainic Acid Receptor Subtype 1 (GluK1) Antagonist (2S,4R)-4-(2-Carboxyphenoxy)pyrrolidine

DEFF Research Database (Denmark)

Krogsgaard-Larsen, Niels; Delgar, Claudia; Koch, Karina

2017-01-01

Ionotropic glutamate receptor antagonists are valuable tool compounds for studies of neurological pathways in the central nervous system. On the basis of rational ligand design, a new class of selective antagonists, represented by (2S,4R)-4-(2-carboxy-phenoxy)pyrrolidine-2-carboxylic acid (1b...... to the structure with glutamate, consistent with 1b being an antagonist. A structure-activity relationship study showed that the chemical nature of the tethering atom (C,O, or S) linking the pyrrolidine ring and the phenyl ring plays a key role in the receptor selectivity profile and that substituents......), for cloned homomeric kainic acid receptor subtype 1 (GluK1) was attained (Ki = 4 µM). In a functional assay, 1b displayed full antagonist activity with IC50 = 6 ± 2 µM. A crystal structure was obtained of 1b when bound in the ligand binding domain of GluK1. A domain opening of 13-14° was seen compared...

Core-shell magnetite-silica dithiocarbamate-derivatised particles achieve the Water Framework Directive quality criteria for mercury in surface waters.

Science.gov (United States)

Lopes, C B; Figueira, P; Tavares, D S; Lin, Z; Daniel-da-Silva, A L; Duarte, A C; Rocha, J; Trindade, T; Pereira, E

2013-09-01

The sorption capacity of nanoporous titanosilicate Engelhard titanosilicate number 4 (ETS-4) and silica-coated magnetite particles derivatised with dithiocarbamate groups towards Hg(II) was evaluated and compared in spiked ultra-pure and spiked surface-river water, for different batch factors. In the former, and using a batch factor of 100 m(3)/kg and an initial Hg(II) concentrations matching the maximum allowed concentration in an effluent discharge, both materials achieve Hg(II) uptake efficiencies in excess of 99 % and a residual metal concentration lower than the guideline value for drinking water quality. For the surface-river water and the same initial concentration, the Hg(II) uptake efficiency of magnetite particles is outstanding, achieving the quality criteria established by the Water Framework Directive (concerning Hg concentration in surface waters) using a batch factor of 50 m(3)/kg, while the efficiency of ETS-4 is significantly inferior. The dissimilar sorbents' Hg(II) removal efficiency is attributed to different uptake mechanisms. This study also highlights the importance of assessing the effective capacity of the sorbents under realistic conditions in order to achieve trustable results.

Synthesis of 99mTcN-clinafloxacin Dithiocarbamate Complex and Comparative Radiobiological Evaluation in Staphylococcus aureus Infected Mice

International Nuclear Information System (INIS)

Shah, Syed Qaiser; Khan, Mohammad Rafiullah

2014-01-01

Clinafloxacin dithiocarbamate (CNND) preparation and radiolabeling through [ 99m Tc ≡ N] 2+ core with the gamma (γ) emitter ( 99m Tc) was assessed. The potentiality of the 99m Tc V ≡ N-CNND complex was investigated as perspective a Staphylococcus aureus (S.a.) in vivo infection radiotracer in terms of radiochemical stability in normal saline (n.s.), human serum (h.s.), binding efficacy with live and heat killed S.a. and biodistribution in female nude mice model (FNMD). More than 90% stability was observed in n.s. for 4 h with the highest yield of 98.70 ± 0.26% at 30 min after reconstitution. In h.s., the 99m Tc V ≡ N-CNND complex was found stable up to 16 h with 15.35% side products. Maximum in vitro binding (68.75 ± 0.80%, 90 min) with S.a. was observed after 90 min of incubation. In FNMD, (infected with live strain) approximately six-fold higher uptakes was noted in the infected to inflamed and normal muscles. The higher stability in n.s., h.s., higher S.a. (live) up take with specific and targeted in vivo distribution confirmed potentiality of the 99m Tc V ≡ N-CNND complex as perspective S.a.in vivo infection radiotracer

Evaluation of Stability of Complexes of Inner Transition Metal Ions with 2-Oxo-1-pyrrolidine Acetamide and Role of Systematic Errors

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Sangita Sharma

2011-01-01

Full Text Available BEST FIT models were used to study the complexation of inner transition metal ions like Y(III, La(III, Ce(III, Pr(III, Nd(III, Sm(III, Gd(III, Dy(III and Th(IV with 2-oxo-1-pyrrolidine acetamide at 30 °C in 10%, 20, 30, 40, 50% and 60% v/v dioxane-water mixture at 0.2 M ionic strength. Irving Rossotti titration method was used to get titration data. Calculations were carried out with PKAS and BEST Fortran IV computer programs. The expected species like L, LH+, ML, ML2 and ML(OH3, were obtained with SPEPLOT. Stability of complexes has increased with increasing the dioxane content. The observed change in stability can be explained on the basis of electrostatic effects, non electrostatic effects, solvating power of solvent mixture, interaction between ions and interaction of ions with solvents. Effect of systematic errors like effect of dissolved carbon dioxide, concentration of alkali, concentration of acid, concentration of ligand and concentration of metal have also been explained here.

Determination of Lead in Urine by Atomic Absorption Spectrophotometry1

Science.gov (United States)

Selander, Stig; Cramé, Kim

1968-01-01

A method for the determination of lead in urine by means of atomic absorption spectrophotometry (AAS) is described. A combination of wet ashing and extraction with ammonium pyrrolidine dithiocarbamate into isobutylmethylketone was used. The sensitivity was about 0·02 μg./ml. for 1% absorption, and the detection limit was about 0·02 μg./ml. with an instrumental setting convenient for routine analyses of urines. Using the scale expansion technique, the detection limit was below 0·01 μg./ml., but it was found easier to determine urinary lead concentrations below 0·05 μg./ml. by concentrating the lead in the organic solvent by increasing the volume of urine or decreasing that of the solvent. The method was applied to fresh urines, stored urines, and to urines, obtained during treatment with chelating agents, of patients with lead poisoning. Urines with added inorganic lead were not used. The results agreed well with those obtained with a colorimetric dithizone extraction method (r = 0·989). The AAS method is somewhat more simple and allows the determination of smaller lead concentrations. PMID:5647975

High performance preconcentration of inorganic Se species by dispersive micro-solid phase extraction with a nanosilica-ionic liquid hybrid material

Science.gov (United States)

Llaver, Mauricio; Coronado, Eduardo A.; Wuilloud, Rodolfo G.

2017-12-01

A highly sensitive and efficient dispersive micro-solid phase extraction (D-μ-SPE) method was developed for inorganic Se speciation analysis. A novel ionic liquid (IL)-nanomaterial hybrid consisting of 1-dodecyl-3-methylimidazolium bromide-functionalized nanosilica was used for the efficient retention of Se(IV) complexed with ammonium pyrrolidine dithiocarbamate, followed by elution with an ethyl acetate/Triton X-114 mixture and determination by electrothermal atomic absorption spectroscopy. The Se(VI) species was selectively determined by difference between total inorganic Se and Se(IV) after pre-reduction. The IL-nanomaterial hybrid was characterized by Fourier transform infrared spectroscopy and transmission electronic microscopy. Likewise, Se(IV) sorption capacity of the retention material and maximum amount of IL loaded on its surface were determined. Several factors concerning the functionalization, extraction and elution steps were optimized, yielding a 100% extraction efficiency for Se(IV) under optimal conditions. A limit of detection of 1.1 ng L- 1, a relative standard deviation of 5.7% and a 110-fold enhancement factor were obtained. The D-μ-SPE method was successfully applied to several water samples from different origins and compositions, including rain, tap, underground, river and sea.

Simultaneous Pre-Concentration of Cadmium and Lead in Environmental Water Samples with Dispersive Liquid-Liquid Microextraction and Determination by Inductively Coupled Plasma-Atomic Emission Spectrometry

Directory of Open Access Journals (Sweden)

M. Salahinejad

2013-06-01

Full Text Available The dispersive liquid–liquid microextraction (DLLME method for determination of Pb+2 and Cd+2 ions in the environmental water samples was combined with inductively coupled plasma-atomic emission spectrometry (ICP-AES. Ammonium pyrrolidine dithiocarbamate (APDC, chloroform and ethanol were used as chelating agent, extraction solvent and disperser solvent, respectively. Some effective parameters on the microextraction and the complex formation were selected and optimized. These parameters included extraction and disperser solvent type as well as their volume, extraction time, salt effect, pH, sample volume and amount of the chelating agent.   Under the optimum conditions, the enrichment factor of 75 and 105 for Cd+2 and Pb+2 ions respectively was obtained from only 5.00mL of water sample. The detection limit (S/N=3 was 12 and 0.8ngmL−1 for Pb and Cd respectively. The relative standard deviation (RSDs for five replicate measurements of 0.50 mgL−1 of lead and cadmium was 6.5 and 4.4 % respectively. Mineral, tap, river, sea, dam and spiked water samples were analyzed for Cd and Pb amount.

An automated flow injection system for metal determination by flame atomic absorption spectrometry involving on-line fabric disk sorptive extraction technique.

Science.gov (United States)

Anthemidis, A; Kazantzi, V; Samanidou, V; Kabir, A; Furton, K G

2016-08-15

A novel flow injection-fabric disk sorptive extraction (FI-FDSE) system was developed for automated determination of trace metals. The platform was based on a minicolumn packed with sol-gel coated fabric media in the form of disks, incorporated into an on-line solid-phase extraction system, coupled with flame atomic absorption spectrometry (FAAS). This configuration provides minor backpressure, resulting in high loading flow rates and shorter analytical cycles. The potentials of this technique were demonstrated for trace lead and cadmium determination in environmental water samples. The applicability of different sol-gel coated FPSE media was investigated. The on-line formed complex of metal with ammonium pyrrolidine dithiocarbamate (APDC) was retained onto the fabric surface and methyl isobutyl ketone (MIBK) was used to elute the analytes prior to atomization. For 90s preconcentration time, enrichment factors of 140 and 38 and detection limits (3σ) of 1.8 and 0.4μgL(-1) were achieved for lead and cadmium determination, respectively, with a sampling frequency of 30h(-1). The accuracy of the proposed method was estimated by analyzing standard reference materials and spiked water samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of molybdenum dithiocarbamate and zinc dialkyl dithiophosphate additives on tribological behaviors of hydrogenated diamond-like carbon coatings

International Nuclear Information System (INIS)

Yue, Wen; Liu, Chunyue; Fu, Zhiqiang; Wang, Chengbiao; Huang, Haipeng; Liu, Jiajun

2014-01-01

Highlights: • For MoDTC, DLC coating showed better anti-friction and worse anti-wear behaviors. • The improved anti-friction property was due to graphitization and MoS 2 . • Formation of MoO x resulted in a high wear volume. • For ZDDP, DLC coating showed the best anti-wear and the worst anti-friction behaviors. • Absence of friction reducing product and graphitized layer resulted in a higher friction. - Abstract: The tribological behaviors of hydrogenated diamond-like carbon (DLC) coatings under varied load conditions lubricated with polyalpha olefin (PAO), molybdenum dithiocarbamate (MoDTC) and zinc dialkyl dithiophosphate (ZDDP) additives were investigated in this paper. Hydrogenated DLC coatings were synthesized through the decomposition of acetylene by the ion source. The tribological performances were measured on a SRV tribometer. The morphologies and chemical structures of the DLC coatings were investigated by the scanning electron microscope (SEM), Raman spectrometer (Raman) and X-ray photoelectron spectroscope (XPS). It was shown that the low friction and high wear were achieved on the hydrogenated DLC coating under MoDTC lubrication, while low wear was found on the hydrogenated DLC coating lubricated by ZDDP. The primary reason was attributed to different tribofilms formed on the contact area and the formation of graphitic layer. Both factors working together leaded to quite different tribological behaviors

Novel Hybrid Anticonvulsants Derived from Pyrrolidine-2,5-dione Scaffold with Broad Spectrum of Activity in the Preclinical Studies.

Science.gov (United States)

Kaminski, Krzysztof

2017-01-01

The multifunctional ligands application is an emerging approach in drug delivery, mainly in the treatment of diseases with complex pathology, such as Alzheimer's, cancer, and epilepsy. Using this method many biomolecules with different properties are combined to form a single unit that can provide a complex broad spectrum activity. Thus, a new type of hybrid anticonvulsants based on the pyrrolidine-2,5-dione frame are detailed with the aim of acquiring more effective antiepileptic drugs (AED) that could suppress various human convulsions. These hybrid molecules attach to the chemical particles of clinically relevant AEDs such as ethosuximide, levetiracetam, and lacosamide. As a result of this hybridization process the compounds obtained were effective in three most important animal epilepsy models, namely the maximal electroshock seizure (MES) test, the subcutaneous pentylenetetrazole (scPTZ) test, and the six-Hertz (6 Hz) model in mice. These substances displayed wider spectrum of protection, more potent efficacy, and better safety profile than the aforementioned AEDs. Several compounds were also active in the formalin model of persistent pain in mice. The in vitro ligand binding studies have proved that the most conceivable molecular mechanism of anticonvulsant and antinociceptive action was the influence on the neuronal voltage-sensitive sodium and L-type calcium channels. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Synthesis, Characterization, and Processing of Copper, Indium, and Gallium Dithiocarbamates for Energy Conversion Applications

Science.gov (United States)

Duraj, S. A.; Duffy, N. V.; Hepp, A. F.; Cowen, J. E.; Hoops, M. D.; Brothrs, S. M.; Baird, M. J.; Fanwick, P. E.; Harris, J. D.; Jin, M. H.-C.

2009-01-01

Ten dithiocarbamate complexes of indium(III) and gallium(III) have been prepared and characterized by elemental analysis, infrared spectra and melting point. Each complex was decomposed thermally and its decomposition products separated and identified with the combination of gas chromatography/mass spectrometry. Their potential utility as photovoltaic materials precursors was assessed. Bis(dibenzyldithiocarbamato)- and bis(diethyldithiocarbamato)copper(II), Cu(S2CN(CH2C6H5)2)2 and Cu(S2CN(C2H5)2)2 respectively, have also been examined for their suitability as precursors for copper sulfides for the fabrication of photovoltaic materials. Each complex was decomposed thermally and the products analyzed by GC/MS, TGA and FTIR. The dibenzyl derivative complex decomposed at a lower temperature (225-320 C) to yield CuS as the product. The diethyl derivative complex decomposed at a higher temperature (260-325 C) to yield Cu2S. No Cu containing fragments were noted in the mass spectra. Unusual recombination fragments were observed in the mass spectra of the diethyl derivative. Tris(bis(phenylmethyl)carbamodithioato-S,S'), commonly referred to as tris(N,N-dibenzyldithiocarbamato)indium(III), In(S2CNBz2)3, was synthesized and characterized by single crystal X-ray crystallography. The compound crystallizes in the triclinic space group P1(bar) with two molecules per unit cell. The material was further characterized using a novel analytical system employing the combined powers of thermogravimetric analysis, gas chromatography/mass spectrometry, and Fourier transform infrared (FT-IR) spectroscopy to investigate its potential use as a precursor for the chemical vapor deposition (CVD) of thin film materials for photovoltaic applications. Upon heating, the material thermally decomposes to release CS2 and benzyl moieties in to the gas phase, resulting in bulk In2S3. Preliminary spray CVD experiments indicate that In(S2CNBz2)3 decomposed on a Cu substrate reacts to produce

Radiocomplexation and biological characterization of the 99mTcN-trovafloxacin dithiocarbamate. A novel methicillin-resistant Staphylococcus aureus infection imaging agent

International Nuclear Information System (INIS)

Syed Qaiser Shah; Muhammad Rafiullah Khan

2011-01-01

The radiolabeling of trovafloxacin dithiocarbamate (TVND) with technetium-99m using [ 99m Tc-N] 2+ core was investigated and biologically assessed as prospective infection imaging agent. The achievability of the 99m TcN-TVND complex as a future MRSA infection radiotracer was investigated in artificially methicillin-resistant Staphylococcus aureus (MRSA) infected male Sprague-Dawley rats (MSDR). Radiochemically the 99m TcN-TVND complex was characterized in terms of radiochemical purity (RCP) in saline, in vitro permanence in serum, in vitro binding with MRSA and biodistribution in living and heat killed MRSA infected MSDR. Radiochemically the complex showed stability in saline with a 97.90 ± 0.22% yield and serum at 37 deg C up to 4 h. The 99m TcN-TVND complex showed saturated in vitro binding with MRSA. Normal in vivo uptake in the MRSA infected MDRS was observed with a five fold uptake in the infected muscle as compared to inflamed and normal muscles. The high RCP values, in vitro permanence in serum, better in vitro binding with MRSA, biodistribution behavior and the target to non-target (infected to inflamed muscle) ratios posed the 99m TcN-TVND complex as a promising MRSA infection radiotracer. (author)

Cloud point extraction combined with electrothermal atomic absorption spectrometry for the speciation of antimony(III) and antimony(V) in food packaging materials

International Nuclear Information System (INIS)

Jiang Xiuming; Wen Shengping; Xiang Guoqiang

2010-01-01

A simple, sensitive method for the speciation of inorganic antimony by cloud point extraction combined with electrothermal atomic absorption spectrometry (ETAAS) is presented and evaluated. The method based on the fact that formation of a hydrophobic complex of antimony(III) with ammonium pyrrolidine dithiocarbamate (APDC) at pH 5.0 and subsequently the hydrophobic complex enter into surfactant-rich phase, whereas antimony(V) remained in aqueous solutions. Antimony(III) in surfactant-rich phase was analyzed by ETAAS after dilution by 0.2 mL nitric acid in methanol (0.1 M), and antimony(V) was calculated by subtracting antimony(III) from the total antimony after reducing antimony(V) to antimony(III) by L-cysteine. The main factors affecting the cloud point extraction, such as pH, concentration of APDC and Triton X-114, equilibrium temperature and incubation time, sample volume were investigated in detail. Under the optimum conditions, the detection limit (3σ) of the proposed method was 0.02 ng mL -1 for antimony(III), and the relative standard deviation was 7.8% (c = 1.0 ng mL -1 , n = 7). The proposed method was successfully applied to speciation of inorganic antimony in the leaching solutions of different food packaging materials with satisfactory results.

A novel separation/preconcentration technique based on ultrasonic dispersion liquid-liquid microextraction for determination of trace cobalt by flame atomic absorption spectrometry

Directory of Open Access Journals (Sweden)

Jingci Li

2012-12-01

Full Text Available An improved method for the determination of trace cobalt in water samples has been developed using ultrasonic dispersion liquid-liquid microextraction (US-DLLME prior to flame atomic absorption spectrometry (FAAS analysis. In this method, cobalt was extracted into the fine droplets of carbon tetrachloride after chelate formation with the water soluble ligand, ammonium pyrrolidine dithiocarbamate (APDC. The fine droplets of carbon tetrachloride were formed and dispersed in the aqueous sample with the help of ultrasonic waves which accelerated the formation of the fine cloudy solution without using disperser solvents. Under optimum conditions, the calibration curve was linear in the range of 2.5-500 μg L-1, with a detection limit of 0.8 μg L-1. The relative standard deviation (RSD for ten replicate measurements of 20 and 500 μg L-1 of cobalt were 3.3 and 2.2%. This proposed method was successfully applied to tap water, river water, and sea water, and accuracy was assessed through the analysis of certified reference water or recovery experiments. Operation simplicity, low cost, high enrichment factor, and low consumption of the extraction solvent are the main advantages of the proposed method.DOI: http://dx.doi.org/10.4314/bcse.v26i1.2

RAPID AND SENSITIVE DETERMINATION OF PALLADIUM USING HOMOGENEOUS LIQUID-LIQUID MICROEXTRACTION VIA FLOTATION ASSISTANCE FOLLOWED BY GRAPHITE FURNACE ATOMIC ABSORPTION SPECTROMETRY

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Mohammad Rezaee

2015-05-01

Full Text Available A method for the determination of trace amounts of palladium was developed using homogeneous liquid-liquid microextraction via flotation assistance (HLLME-FA followed by graphite furnace atomic absorption spectrometry (GFAAS. Ammonium pyrrolidine dithiocarbamate (APDC was used as a complexing agent. This was applied to determine palladium in three types of water samples. In this study, a special extraction cell was designed to facilitate collection of the low-density solvent extraction. No centrifugation was required in this procedure. The water sample solution was added to the extraction cell which contained an appropriate mixture of extraction and homogeneous solvents. By using air flotation, the organic solvent was collected at the conical part of the designed cell. Parameters affecting extraction efficiency were investigated and optimized. Under the optimum conditions, the calibration graph was linear in the range of 1.0-200 µg L-1 with a limit of detection of 0.3 µg L-1. The performance of the method was evaluated for the extraction and determination of palladium in water samples and satisfactory results were obtained. In order to verify the accuracy of the approach, the standard addition method was applied for the determination of palladium in spiked synthetic samples and satisfactory results were obtained.

Biotransformation of Daclatasvir In Vitro and in Nonclinical Species: Formation of the Main Metabolite by Pyrrolidine δ-Oxidation and Rearrangement.

Science.gov (United States)

Li, Wenying; Zhao, Weiping; Liu, Xiaohong; Huang, Xiaohua; Lopez, Omar D; Leet, John E; Fancher, R Marcus; Nguyen, Van; Goodrich, Jason; Easter, John; Hong, Yang; Caceres-Cortes, Janet; Chang, Shu Y; Ma, Li; Belema, Makonen; Hamann, Lawrence G; Gao, Min; Zhu, Mingshe; Shu, Yue-Zhong; Humphreys, W Griffith; Johnson, Benjamin M

2016-06-01

Daclatasvir is a first-in-class, potent, and selective inhibitor of the hepatitis C virus nonstructural protein 5A replication complex. In support of nonclinical studies during discovery and exploratory development, liquid chromatography-tandem mass spectrometry and nuclear magnetic resonance were used in connection with synthetic and radiosynthetic approaches to investigate the biotransformation of daclatasvir in vitro and in cynomolgus monkeys, dogs, mice, and rats. The results of these studies indicated that disposition of daclatasvir was accomplished mainly by the release of unchanged daclatasvir into bile and feces and, secondarily, by oxidative metabolism. Cytochrome P450s were the main enzymes involved in the metabolism of daclatasvir. Oxidative pathways included δ-oxidation of the pyrrolidine moiety, resulting in ring opening to an aminoaldehyde intermediate followed by an intramolecular reaction between the aldehyde and the proximal imidazole nitrogen atom. Despite robust formation of the resulting metabolite in multiple systems, rates of covalent binding to protein associated with metabolism of daclatasvir were modest (55.2-67.8 pmol/mg/h) in nicotinamide adenine dinucleotide phosphate (reduced form)-supplemented liver microsomes (human, monkey, rat), suggesting that intramolecular rearrangement was favored over intermolecular binding in the formation of this metabolite. This biotransformation profile supported the continued development of daclatasvir, which is now marketed for the treatment of chronic hepatitis C virus infection. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

An evaluation of the performance and mechanistic action of the costabiliser N-phenyl-3-acetyl pyrrolidine-2,4-dione and its derivatives in poly(vinyl chloride)

International Nuclear Information System (INIS)

Chaudhry, H.I.

1999-10-01

N-phenyl-3-acetyl pyrrolidine-2,4-dione (F6) and its derivatives (F6c and F6d) have been investigated as costabilisers for PVC at processing temperatures, along with the commercial costabilisers: dehydroacetic acid (DHA) and Rhodiostab-83 (R83). Spectroscopic (fluorescence, Fourier-transform infrared and nuclear magnetic resonance) studies on PVC itself, and model compounds of PVC impurities (e.g. 4-chloro-2-hexene) have shown two distinct modes of action: in which a metal complex between the costabiliser and a metal soap stabiliser (zinc stearate and calcium stearate is the active entity, one in which costabiliser action is facilitated by release of zinc chloride. F6 was shown to substitute for allylic chloride by a C-alkylation reaction so inhibiting polyene formation and giving very good initial colour. It was demonstrated that F6 formed a complex with the zinc stearate at room temperature to give a chelate in which the zinc ion is tetracoordinated. Because the costabiliser is able to co-ordinate readily to zinc stearate, this leads to good initial colour, but a more rapid evolution of HCl ('short-term' costabilisation). When the -C=O substituent in the 3-position was replaced by a '-C=N-alkyl' (F6d), or a '-C=N-phenyl' (F6c) group, the behaviour was changed markedly. FTIR and HCl evolution showed that F6d was unstable at 180 deg. C and reacted with HCl evolved from the degraded PVC, decomposing into a basic gas and a structure similar to F6. F6d being more basic formed a complex with the Lewis acid ZnCI 2 instead of zinc stearate. F6c did not interact with the ZnCl 2 or ZnSt 2 , despite the fact that it has an extra nitrogen atom. The reason for this is that the π orbital system of the N-substituted phenyl ring in the 3-position in the pyrrolidine ring is conjugated with the C=N double bond. DHA also interacted with the zinc stearate, but this interaction was significant only at higher temperatures, i.e. after heating to processing temperatures. The

99mTc(CO)3-tosufloxacin dithiocarbamate complexation and radiobiological evaluation in male Wister rat model

International Nuclear Information System (INIS)

Syed Qaiser Shah; Muhammad Rafiullah Khan

2011-01-01

In the current investigation tosufloxacin (TSN) was derivatized to its dithiocarbamate (TSND) derivative and its radiolabeling with technetium-99m using [ 99m Tc(CO) 3 (H 2 O) 3 ] + precursor. The labeled TSND ( 99m Tc(CO) 3 -TSND) was radiochemically characterized in saline and serum and biologically its in vitro binding with Proteus mirabilis (P. mirabilis) and biodistribution in male Wister rats (MWR) artificially infected with live and heat killed P. mirabilis. Radiochemically a stable radio-tricarbonyl TSND complex was observed with a maximum stability of 98.15 ± 0.32% and it remained more than 90% up to 4 h after reconstitution. The stability decreased to 91.00 ± 0.30% from 98.15 ± 0.32% within 4 h. In serum at 37 deg C the growth of some unwanted side product decreased the stability by 15.65% within 16 h. The complex showed saturated in vitro binding with P. mirabilis up to 78.50% (90 min). In MWR infected with live P. mirabilis the percent (%) uptake of the complex in blood, liver, spleen, stomach, intestines and kidneys were almost similar to the MWR infected with heat killed. However, the % accumulation of the complex in the infected muscle was six times higher than in the inflamed and normal muscle in MWR infected with live P. mirabilis. On the basis of immovability of the 99m Tc(CO) 3 -TSND complex in normal saline, in vitro permanence in serum, saturated in vitro binding with P. mirabilis and six fold uptake in the infected muscle of the MWR infected with live P. mirabilis as compared to the normal muscle, the suitability of the 99m Tc(CO) 3 -TSND complex is established as a promising infection radiotracer. (author)

Evaluation of 99mTcN-moxifloxacin dithiocarbamate, as a potential radiopharmaceutical for scintigraphic localization of infectious foci

International Nuclear Information System (INIS)

Syed Qaiser Shah; Muhammad Rafiullah Khan

2011-01-01

In the current study radio complexation of the moxifloxacin dithiocarbamate (MXND) with technetium-99m ( 99m Tc) using the [ 99m Tc-N] 2+ core through legend exchange reaction was explored. The 99m TcN-MXND complex was biologically evaluated as a potential radiopharmaceutical for in vivo scintigraphy using artificially infected male sprague-dawley rats (MSDR) with Staphylococcus aureus (S. aureus). The radiochemistry of the complex was explored in terms of radiochemical purity (RCP), in vitro stability in serum at 37 deg C for 16 h, in vitro binding with S. aureus and biodistribution in artificially infected with S. aureus MSDR. It was observed that the complex showed stability of more than 90% up to 4 h after reconstitution with a maximum RCP value of 97.55 ± 0.42% at 30 min. The complex showed significantly in vitro stability in serum at 37 deg C with an insignificant free species up to 16.50% within 16 h. In vitro saturated binding with S. aureus was noted up to 120 min with maximum value of 73.25% at 90 min of incubation. Almost sixfold uptake was noted in the infected muscle of the MSDR as compared to inflamed and normal muscle. The 97.55 ± 0.42% RCP values, stability in serum with insignificant untagged 16.50% species, 73.25% in vitro binding with S. aureus and sixfold uptake in the target organ posed the 99m TcN-MXND complex as a promising radiopharmaceutical for S. aureus infectious foci. (author)

Radiosynthesis and biodistribution of 99mTc-tricarbonyl complex of temafloxacin dithiocarbamate. A potential Streptococci pneumoniae infection radiotracer

International Nuclear Information System (INIS)

Syed Qaiser Shah; Muhammad Rafiullah Khan

2011-01-01

In the current investigation the complexation of derivatized temafloxacin with 99m Tc using [ 99m Tc(CO) 3 (H 2 O) 3 ] + precursor was assessed. The tricarbonyl complex of the temafloxacin dithiocarbamate ( 99m Tc(CO) 3 -TAND) was characterized in terms of radiochemical purity (RCP) yield in saline, in vitro radiochemical stability in serum, in vitro binding with Streptococci pneumoniae and biodistribution in male Wister rats (MWR) artificially infected with living and heat killed Streptococci pneumoniae. The 99m Tc(CO) 3 -TAND complex showed 98.10 ± 15% RCP value at 30 min of the reconstitution and remained more than 90% stable up to 120 min in normal saline at room temperature. In serum a stable behavior with the appearance of 15.30% unwanted side product up to 16 h of incubation was observed. A saturated in vitro binding with Streptococci pneumoniae was observed. The complex showed almost six times higher uptake in the infected muscle as compared to the inflamed and normal muscles of the MWR infected with living Streptococci pneumoniae. Insignificant difference in the uptake of the tracer in the infected, inflamed and normal muscles of the MWR infected with heat killed Streptococci pneumoniae was noted. Based on the elevated RCP in saline, in vitro stability in serum at 37 deg C, saturated in vitro binding with pathogens and better biodistribution behavior with higher accumulation of the tracer in target organs confirmed the suitability of the 99m Tc(CO) 3 -TAND complex as promising infection radiotracer. (author)

Nonanaplastic follicular cell-derived thyroid carcinoma: mitosis and necrosis in long-term follow-up.

Science.gov (United States)

Skansing, Daniel Bräuner; Londero, Stefano Christian; Asschenfeldt, Pia; Larsen, Stine Rosenkilde; Godballe, Christian

2017-06-01

Nonanaplastic follicular cell-derived thyroid carcinoma (NAFCTC) includes differentiated- (DTC) and poorly differentiated thyroid carcinoma (PDTC). DTC has an excellent prognosis, while PDTC is situated between DTC and anaplastic carcinomas. Short-term studies suggest that PDTC patients diagnosed only on tumor necrosis and/or mitosis have a prognosis similar to those diagnosed according to the TURIN proposal. The purpose of this study was to evaluate prognosis for NAFCTC based on long-term follow-up illuminating the significance of tumor necrosis and mitosis. A cohort of 225 patients with NAFCTC was followed more than 20 years. Age, sex, distant metastasis, histology, tumor size, extrathyroidal invasion, lymph node metastasis, tumor necrosis and mitosis were examined as possible prognostic factors. Median follow-up time for patients alive was 28 years (range 20-43 years). Age, distant metastasis, extrathyroidal invasion, tumor size, tumor necrosis and mitosis were independent prognostic factors in multivariate analysis for overall survival (OS). In disease specific survival (DSS) age was not significant. Using only necrosis and/or mitosis as criteria for PDTC the 5-, 10- and 20-year OS for DTC was 87, 79 and 69%, respectively. In DSS it was 95, 92 and 90%. For PDTC the 5-, 10- and 20-year OS was 57, 40 and 25%, respectively. In DSS it was 71, 55 and 48%. Tumor necrosis and mitosis are highly significant prognostic indicators in analysis of long time survival of nonanaplastic follicular cell-derived thyroid carcinoma indicating that a simplification of the actually used criteria for poorly differentiated carcinomas may be justified.

Kinetic investigation of uranyl-uranophile complexation. 1. Macrocyclic kinetic effect and macrocyclic protection effect

International Nuclear Information System (INIS)

Tabushi, I.; Yoshizawa, A.

1986-01-01

Equilibria and rates of ligand-exchange reactions between uranyl tricarbonate and dithiocarbamates and between uranyl tris-(dithiocarbamates) and carbonate were studied under a variety of conditions. The dithiocarbamates used were acyclic diethyl-dithiocarbamate and macrocyclic tris(dithiocarbamate). The acyclic ligand showed a triphasic (successive three-step) equilibrium with three different equilibrium constants while the macrocyclic ligand showed a clear monophasic (one-step) equilibrium with a much larger stability constant for the dithiocarbamate-uranyl complex. The macrocyclic ligand showed the S/sub N/2-type ligand-exchange rate in the forward as well as reverse process, while the first step of the acyclic ligand-exchange reaction proceeded via the S/sub N/1-type mechanism. This kinetic macrocyclic effect on molecularity is interpreted as the result of a unique topological requirement of uranyl complexation. The macrocyclic ligand also exhibited a clear protection effect, leading to the large stability constant. 19 references, 10 figures, 2 tables

Ligand-conjugated mesoporous silica nanorattles based on enzyme targeted prodrug delivery system for effective lung cancer therapy

Energy Technology Data Exchange (ETDEWEB)

Sundarraj, Shenbagamoorthy, E-mail: sundarrajbu09@gmail.com [Proteomics and Molecular Cell Physiology Laboratory, Department of Zoology, Bharathiar University, Coimbatore 641 046, TN (India); Thangam, Ramar [Proteomics and Molecular Cell Physiology Laboratory, Department of Zoology, Bharathiar University, Coimbatore 641 046, TN (India); Department of Virology, King Institute of Preventive Medicine and Research, Guindy, Chennai 600 032, TN (India); Sujitha, Mohanan V.; Vimala, Karuppaiya [Proteomics and Molecular Cell Physiology Laboratory, Department of Zoology, Bharathiar University, Coimbatore 641 046, TN (India); Kannan, Soundarapandian, E-mail: skperiyaruniv@gmail.com [Proteomics and Molecular Cell Physiology Laboratory, Department of Zoology, Bharathiar University, Coimbatore 641 046, TN (India); Department of Zoology, Periyar University, Salem 636 011, TN (India)

2014-03-15

Epidermal growth factor receptor antibody (EGFRAb) conjugated silica nanorattles (SNs) were synthesized and used to develop receptor mediated endocytosis for targeted drug delivery strategies for cancer therapy. The present study determined that the rate of internalization of silica nanorattles was found to be high in lung cancer cells when compared with the normal lung cells. EGFRAb can specifically bind to EGFR, a receptor that is highly expressed in lung cancer cells, but is expressed at low levels in other normal cells. Furthermore, in vitro studies clearly substantiated that the cPLA{sub 2}α activity, arachidonic acid release and cell proliferation were considerably reduced by pyrrolidine-2 loaded EGFRAb-SN in H460 cells. The cytotoxicity, cell cycle arrest and apoptosis were significantly induced by the treatment of pyrrolidine-2 loaded EGFRAb-SN when compared with free pyrrolidine-2 and pyrrolidine-2 loaded SNs in human non-small cell lung cancer cells. An in vivo toxicity assessment showed that silica nanorattles and EGFRAb-SN-pyrrolidine-2 exhibited low systemic toxicity in healthy Balb/c mice. The EGFRAb-SN-pyrrolidine-2 showed a much better antitumor activity (38%) with enhanced tumor inhibition rate than the pyrrolidine-2 on the non-small cell lung carcinoma subcutaneous model. Thus, the present findings validated the low toxicity and high therapeutic potentials of EGFRAb-SN-pyrrolidine-2, which may provide a convincing evidence of the silica nanorattles as new potential carriers for targeted drug delivery systems. - Highlights: • EGFRAb-SN developed for receptor-mediated Drug delivery system (DDS). • EGFRAb-SN-pyrrolidine-2 targeted DDS for cPLA2α inhibition in NSLC. • Study indicates EGFRAb-SN-pyrrolidine-2 as an efficient in target dug delivery carrier. • Study explains entire efficiency of EGFRAb-SN-pyrrolidine-2 in vitro and in vivo models.

Ligand-conjugated mesoporous silica nanorattles based on enzyme targeted prodrug delivery system for effective lung cancer therapy

International Nuclear Information System (INIS)

Sundarraj, Shenbagamoorthy; Thangam, Ramar; Sujitha, Mohanan V.; Vimala, Karuppaiya; Kannan, Soundarapandian

2014-01-01

Epidermal growth factor receptor antibody (EGFRAb) conjugated silica nanorattles (SNs) were synthesized and used to develop receptor mediated endocytosis for targeted drug delivery strategies for cancer therapy. The present study determined that the rate of internalization of silica nanorattles was found to be high in lung cancer cells when compared with the normal lung cells. EGFRAb can specifically bind to EGFR, a receptor that is highly expressed in lung cancer cells, but is expressed at low levels in other normal cells. Furthermore, in vitro studies clearly substantiated that the cPLA 2 α activity, arachidonic acid release and cell proliferation were considerably reduced by pyrrolidine-2 loaded EGFRAb-SN in H460 cells. The cytotoxicity, cell cycle arrest and apoptosis were significantly induced by the treatment of pyrrolidine-2 loaded EGFRAb-SN when compared with free pyrrolidine-2 and pyrrolidine-2 loaded SNs in human non-small cell lung cancer cells. An in vivo toxicity assessment showed that silica nanorattles and EGFRAb-SN-pyrrolidine-2 exhibited low systemic toxicity in healthy Balb/c mice. The EGFRAb-SN-pyrrolidine-2 showed a much better antitumor activity (38%) with enhanced tumor inhibition rate than the pyrrolidine-2 on the non-small cell lung carcinoma subcutaneous model. Thus, the present findings validated the low toxicity and high therapeutic potentials of EGFRAb-SN-pyrrolidine-2, which may provide a convincing evidence of the silica nanorattles as new potential carriers for targeted drug delivery systems. - Highlights: • EGFRAb-SN developed for receptor-mediated Drug delivery system (DDS). • EGFRAb-SN-pyrrolidine-2 targeted DDS for cPLA2α inhibition in NSLC. • Study indicates EGFRAb-SN-pyrrolidine-2 as an efficient in target dug delivery carrier. • Study explains entire efficiency of EGFRAb-SN-pyrrolidine-2 in vitro and in vivo models

Synthesis, and anticonvulsant activity of new amides derived from 3-methyl- or 3-ethyl-3-methyl-2,5-dioxo-pyrrolidin-1-yl-acetic acids.

Science.gov (United States)

Obniska, Jolanta; Rapacz, Anna; Rybka, Sabina; Góra, Małgorzata; Kamiński, Krzysztof; Sałat, Kinga; Żmudzki, Paweł

2016-04-15

This paper describes the synthesis of the library of 22 new 3-methyl- and 3-ethyl-3-methyl-2,5-dioxo-pyrrolidin-1-yl-acetamides as potential anticonvulsant agents. The maximal electroshock (MES) and the subcutaneous pentylenetetrazole (scPTZ) seizure models were used for screening all the compounds. The 6 Hz model of pharmacoresistant limbic seizures was applied for studying selected derivatives. Six amides were chosen for pharmacological characterization of their antinociceptive activity in the formalin model of tonic pain as well as local anesthetic activity was assessed in mice. The pharmacological data indicate on the broad spectra of activity across the preclinical seizure models. Compounds 10 (ED50=32.08 mg/kg, MES test) and 9 (ED50=40.34 mg/kg, scPTZ test) demonstrated the highest potency. These compounds displayed considerably better safety profiles than clinically relevant antiepileptic drugs phenytoin, ethosuximide, or valproic acid. Several molecules showed antinociceptive and local anesthetic properties. The in vitro radioligand binding studies demonstrated that the influence on the sodium and calcium channels may be one of the essential mechanisms of action. Copyright © 2016. Published by Elsevier Ltd.

The antiproliferative activity of di-2-pyridylketone dithiocarbamate is partly attributed to catalase inhibition: detailing the interaction by spectroscopic methods.

Science.gov (United States)

Li, Cuiping; Liu, Youxun; Fu, Yun; Huang, Tengfei; Kang, Lixia; Li, Changzheng

2017-08-22

The bioactivity of drugs is attributed to their interaction with biological molecules, embodied in either their direct or indirect influence on enzyme activity and conformation. Di-2-pyridylketone hydrazine dithiocarbamate (DpdtC) exhibits significant antitumor activity in our preliminary study. We speculated that its activity may partly stem from enzyme inhibition due to strong metal chelating ability. To this end, we assessed its effect on catalase from erythrocytes and found evidence of inhibition, which was further confirmed by ROS determination in vivo. Thus, detailing the interaction between the agent and catalase via spectroscopic methods and molecular docking was required to obtain information on both the dynamics and thermodynamic parameters. The Lineweaver-Burk plot implied an uncompetitive pattern between DpdtC and catalase from beef liver, and IC 50 = ∼7 μM. The thermodynamic parameters from fluorescence quenching measurements indicated that DpdtC could bind to catalase with moderate affinity (K a = approximately 10 4 M -1 ). CD spectra revealed that DpdtC could significantly disrupt the secondary structure of catalase. Docking studies indicated that DpdtC bound to a flexible region of catalase, involving hydrogen bonds and salt bond; this was consistent with thermodynamic results from spectral investigations. Our data clearly showed that catalase inhibition of DpdtC was not due to direct chelation of iron from heme (killing), but through an allosteric effect. Thus, it can be concluded that the antiproliferative activity of DpdtC is partially attributed to its catalase inhibition.

Radiosynthesis and biological evaluation of the 99mTc-tricarbonyl moxifloxacin dithiocarbamate complex as a potential Staphylococcus aureus infection radiotracer

International Nuclear Information System (INIS)

Shah, Syed Qaiser; Khan, Muhammad Rafiullah

2011-01-01

In the present investigation, radiosynthesis of the 99m Tc-tricarbonyl moxifloxacin dithiocarbamate complex ( 99m Tc(CO) 3 -MXND) and its biological evaluation in male Wister rats (MWR) artificially infected with Staphylococcus aureus (S. aureus) was assessed. The 99m Tc(CO) 3 -MXND complex was radiochemically examined in terms of stability in saline and in serum and biologically its in-vitro binding with S. aureus and percent absorption in MWR models. Radiochemically the 99m Tc(CO) 3 -MXND complex showed more than 90% stability in saline up to 240 min and in serum 14.95% undesirable species was appeared within 16 h. In-vitro the 99m Tc(CO) 3 -MXND complex showed saturated binding with S. aureus. In MWR artificially infected with live S. aureus the complex showed about six fold higher uptakes in the infected muscle as compared to the normal muscle. However, insignificant change in the uptake of 99m Tc(CO) 3 -MXND complex in the infected and inflamed or normal muscle was observed in the MWR infected with heat killed S. aureus. The 99m Tc(CO) 3 -MXND complex disappeared from the circulatory system and appeared in the urinary system within 60-90 min followed by excretion through normal route of urinary system. Based on the elevated and stable radiochemical succumb in saline, serum, saturated in-vitro binding with S. aureus and higher accumulation in the target organ of the MWR, we recommend the 99m Tc(CO) 3 -MXND complex for radio-localization of the infection induced by S. aureus in human.

Passivating ZnO Surface States by C60 Pyrrolidine Tris-Acid for Hybrid Solar Cells Based on Poly(3-hexylthiophene/ZnO Nanorod Arrays

Directory of Open Access Journals (Sweden)

Peng Zhong

2017-12-01

Full Text Available Construction of ordered electron acceptors is a feasible way to solve the issue of phase separation in polymer solar cells by using vertically-aligned ZnO nanorod arrays (NRAs. However, the inert charge transfer between conducting polymer and ZnO limits the performance enhancement of this type of hybrid solar cells. In this work, a fullerene derivative named C60 pyrrolidine tris-acid is used to modify the interface of ZnO/poly(3-hexylthiophene (P3HT. Results indicate that the C60 modification passivates the surface defects of ZnO and improves its intrinsic fluorescence. The quenching efficiency of P3HT photoluminescence is enhanced upon C60 functionalization, suggesting a more efficient charge transfer occurs across the modified P3HT/ZnO interface. Furthermore, the fullerene modified hybrid solar cell based on P3HT/ZnO NRAs displays substantially-enhanced performance as compared to the unmodified one and the devices with other modifiers, which is contributed to retarded recombination and enhanced exciton separation as evidenced by electrochemical impedance spectra. Therefore, fullerene passivation is a promising method to ameliorate the connection between conjugated polymers and metal oxides, and is applicable in diverse areas, such as solar cells, transistors, and light-emitting dioxides.

Surfactant-enhanced liquid-liquid microextraction coupled to micro-solid phase extraction onto highly hydrophobic magnetic nanoparticles

International Nuclear Information System (INIS)

Giannoulis, Kiriakos M.; Giokas, Dimosthenis L.; Tsogas, George Z.; Vlessidis, Athanasios G.; Zhu, Qing; Pan, Qinmin

2013-01-01

We are presenting a simplified alternative method for dispersive liquid-liquid microextraction (DLLME) by resorting to the use of surfactants as emulsifiers and micro solid-phase extraction (μ-SPE). In this combined procedure, DLLME of hydrophobic components is initially accomplished in a mixed micellar/microemulsion extractant phase that is prepared by rapidly mixing a non-ionic surfactant and 1-octanol in aqueous medium. Then, and in contrast to classic DLLME, the extractant phase is collected by highly hydrophobic polysiloxane-coated core-shell Fe 2 O 3 (at)C magnetic nanoparticles. Hence, the sample components are the target analyte in the DLLME which, in turn, becomes the target analyte of the μ-SPE step. This 2-step approach represents a new and simple DLLME procedure that lacks tedious steps such as centrifugation, thawing, or delicate collection of the extractant phase. As a result, the analytical process is accelerated and the volume of the collected phase does not depend on the volume of the extraction solvent. The method was applied to extract cadmium in the form of its pyrrolidine dithiocarbamate chelate from spiked water samples prior to its determination by FAAS. Detection limits were brought down to the low μg L −1 levels by preconcentrating 10 mL samples with satisfactory recoveries (96.0–108.0 %). (author)

Mitochondrial Reactive Oxygen Species Trigger Hypoxia-Induced Transcription

Science.gov (United States)

Chandel, N. S.; Maltepe, E.; Goldwasser, E.; Mathieu, C. E.; Simon, M. C.; Schumacker, P. T.

1998-09-01

Transcriptional activation of erythropoietin, glycolytic enzymes, and vascular endothelial growth factor occurs during hypoxia or in response to cobalt chloride (CoCl2) in Hep3B cells. However, neither the mechanism of cellular O2 sensing nor that of cobalt is fully understood. We tested whether mitochondria act as O2 sensors during hypoxia and whether hypoxia and cobalt activate transcription by increasing generation of reactive oxygen species (ROS). Results show (i) wild-type Hep3B cells increase ROS generation during hypoxia (1.5% O2) or CoCl2 incubation, (ii) Hep3B cells depleted of mitochondrial DNA (ρ 0 cells) fail to respire, fail to activate mRNA for erythropoietin, glycolytic enzymes, or vascular endothelial growth factor during hypoxia, and fail to increase ROS generation during hypoxia; (iii) ρ 0 cells increase ROS generation in response to CoCl2 and retain the ability to induce expression of these genes; and (iv) the antioxidants pyrrolidine dithiocarbamate and ebselen abolish transcriptional activation of these genes during hypoxia or CoCl2 in wild-type cells, and abolish the response to CoCl2 in ρ 0 cells. Thus, hypoxia activates transcription via a mitochondria-dependent signaling process involving increased ROS, whereas CoCl2 activates transcription by stimulating ROS generation via a mitochondria-independent mechanism.

Tumor Necrosis Factor-α Is Required for Mast Cell-Mediated Host Immunity Against Cutaneous Staphylococcus aureus Infection.

Science.gov (United States)

Liu, Chao; Ouyang, Wei; Xia, Jingyan; Sun, Xiaoru; Zhao, Liying; Xu, Feng

2018-05-08

Mast cells (MCs) play a key role in immune process response to invading pathogens. This study assessed the involvement of MCs in controlling Staphylococcus aureus infection in a cutaneous infection model of MC-deficient (KitW-sh/W-sh) mice. KitW-sh/W-sh mice developed significantly larger skin lesions after the cutaneous S. aureus challenge, when compared to wild-type (WT) mice, while MC dysfunction reduced the inflammation response to S. aureus. The levels of tumor necrosis factor (TNF)-α in skin tissues were significantly decreased in KitW-sh/W-sh mice upon infection. Moreover, the exogenous administration of MCs or recombinant TNF-α effectively restored the immune response against S. aureus in KitW-sh/W-sh mice via the recruitment of neutrophils to the infected site. These results indicate that the effects of MC deficiency are largely attributed to the decrease in production of TNF-α in cutaneous S. aureus infection. In addition, S. aureus-induced MC activation was dependent on the c-kit receptor-activated phosphoinositide 3-kinase (PI3K)/AKT/P65-nuclear factor (NF-κB) pathway, which was confirmed by treatment with Masitinib (a c-kit receptor inhibitor), Wortmannin (a PI3K inhibitor), and pyrrolidine dithiocarbamate (a NF-κB inhibitor), respectively. The present study identifies the critical role of MCs in the host defense against S. aureus infection.

99mTc(CO)3-Garenoxacin dithiocarbamate synthesis and biological evolution in rats infected with multiresistant Staphylococcus aureus and penicillin-resistant Streptococci

International Nuclear Information System (INIS)

Syed Qaiser Shah; Aakif Ullah Khan; Muhammad Rafiullah Khan

2011-01-01

99m Tc(CO) 3 -Garenoxacin dithiocarbamate ( 99m Tc(CO) 3 -GXND) complex was synthesized and biologically characterized in rats artificially infected with multiresistant Staphylococcus aureus (MDRSA) and penicillin-resistant Streptococci (PRSC). The characteristics of the 99m Tc(CO) 3 -GXND complex was assessed in terms of radiochemical stability in saline, serum, in vitro binding with live and heat killed MDRSA and PRSC and biodistribution in rats artificially infected with MDRSA and PRSC. The complex showed maximum radiochemical stability at 30 min and remained more than 90% stable up to 240 min in normal saline after reconstitution. The complex was found stable in serum at 37 deg C up to 16 h. The complex showed in vitro saturated binding with living MDRSA and PRSC. In rats infected with living MDRSA and PRSC the complex showed five higher up take in the infected muscle as compared to the inflamed and normal muscle. No significant difference in uptake of the complex in rats infected with heat killed MDRSA and PRSC was observed. The disappearance of the complex from the blood and appearance in the urinary system confirm the normal biological route of biodistribution and excretion. The high values of the radiochemical stability in normal saline, serum, saturated in vitro binding with living MDRSA and PRSC and significant infected to normal muscles ratios, the 99m Tc(CO) 3 -GXND complex is recommended for the localization of soft tissue infection caused by living MDRSA and PRSC. (author)

Study of magnetization switching for MRAM based memory technologies

Science.gov (United States)

Pham, Huy

Amphibian alkaloids are attractive targets for synthesis due to their biological activity. An important class of amphibian alkaloids is the 2,5-disubstituted pyrrolidine-based family of compounds. There are many synthetic approaches for the preparation of the trans-2,5-disubstituted pyrrolidines, but methods for the construction of the cis-2,5-pyrrolidines are limited. Therefore, it was desired to develop an enantioselective approach for the preparation of cis-2,5-disubsituted pyrrolidines. (+)-Tropin-2-one derived from cocaine was used as starting material to exploit the inherent stereochemistry for construction of the cis-pyrrolidine ring. This permitted the unequivocal assignment of the absolute configuration of the target pyrrolidine. The structurally simple pyrrolidine alkaloid, 225H, was selected as a target to develop a general synthetic approach. The enantioselective synthesis of 225H was achieved in nine steps and good overall yield. The search for potent cannabinoid receptor partial agonist ligands as potential marijuana addiction therapeutic agents has led to an investigation of the synthesis of diaryl ether hybrid analogues of BAY 59-3074. A series of 2-(3-alkyl-5-hydroxyphenoxy)-6-(trifluoromethyl)benzonitriles, 3-(2-cyano-3-(trifluoromethyl)phenoxy)phenylalkanoates, and (3-(benzyloxy)phenoxy)-6-(trifluoromethyl)benzonitriles were synthesized and evaluated in vitro for CB1 affinity. The olivetol diaryl ether analogue was the most potent ligand of the alkyl series, but the diaryl ester analogues exhibited modest affinity for CB1 receptors. The most potent compound of the series was the 2-(3-(benzyloxy)phenoxy)-6-(trifluoromethyl)benzonitrile. Keywords. amphibian alkaloids, enantioselective synthesis, pyrrolidine, cannabinoid receptor, marijuana.

Carbonate binding to copper(II) in solution: mixed-ligand complex formation and its application to the isolation and separation of the three isomers of [Cu(bpp)(H₂O)][ClO₄]₂ [bpp = 2,6-bis(pyrrolidin-2-yl)pyridine

OpenAIRE

Bernauer, Klaus; Godefroy, Isabelle; Cabort, Amel; Guicher, Nathalie; Stoeckli-Evans, Helen; Süss-Fink, Georg

2006-01-01

The binding of the carbonate anion to [Cu(meso-bpp)(H2O)]2+ and rac-[Cu(bpp)(H2O)]2+ [bpp = 2,6-bis(pyrrolidin-2-yl)pyridine] in aqueous solution has been investigated. Formation constants of the carbonato complexes [Cu(meso-bpp)(CO3)] and rac-[Cu(bpp)(CO3)] (1.02 × 103 M–1 and 1.77 × 103 M–1, respectively, µ= 0.70 M) have been calculated from spectrophotometric measurements. The formation of these Cu2+ complexes can also be used for an improved synthesis and an easy isolation of the three di...

Synthesis of the 99mTc(CO)3-trovafloxacin dithiocarbamate complex and biological characterization in artificially methicillin-resistant Staphylococcus aureus infected rats model

International Nuclear Information System (INIS)

Syed Qaiser Shah; Muhammad Rafiullah Khan

2011-01-01

Synthesis of the 99m Tc(CO) 3 -trovafloxacin dithiocarbamate ( 99m Tc(CO) 3 -TVND) complex and biological characterization in artificially Staphylococcus aureus (S. aureus) infected rats model was assessed. The suitability of the complex was evaluated and compared with 99m TcN-TVND, in terms of radiochemical immovability in saline, in vitro permanence in serum, in vitro binding with S. aureus and biodistribution in Male Sprague-Dawley rats (MSDR). After 30 min of the reconstitution both the complexes showed maximum radiochemical stabilities in saline and remain more than 90% stable up to 120 min. However the 99m Tc(CO) 3 -TVND showed to some extent higher stability than 99m TcN-TVND complex. In serum 1.75% less de-tagging was observed than 99m TcN-TVND complex. Both the complexes showed saturated in vitro binding with S. aureus and no significant difference were observed between the uptakes. Six fold uptakes were noted in the infected muscle as compared to the inflamed and normal muscles of the MDSR. The uptake of the 99m Tc(CO) 3 -TVND in infected muscle of the MSDR was 2.25% high as compared to the 99m TcN-TVND complex. Based on radiochemical stabilities in saline, serum, in vitro binding with MRSA and significantly higher uptake in the infected muscle, we recommend both the complexes for in vivo investigation of the MRSA infection in human. (author)

Synthesis of 99mTcV ≡ N-Pazufloxacin dithiocarbamate complex and biological evaluation in Wister rats artificially infected with Escherichia coli

International Nuclear Information System (INIS)

Syed Qaiser Shah; Muhammad Rafiullah Khan

2011-01-01

99m Tc ≡ N-Pazufloxacin dithiocarbamate ( 99m Tc ≡ N-PZN) complex was synthesized through the [ 99m Tc ≡ N] 2+ core and its aptness was radiochemically and biologically evaluated in terms of radiochemical purity (RCP) in saline, in vitro stability in serum, in vitro bacterial uptake and percent in vivo uptake in male Wister rats (MWR) artificially infected with alive and heat killed Escherichia coli (E. coli). The 99m Tc ≡ N-PZN complex showed more than 90% RCP up to 4 h after reconstitution in normal saline at room temperature with a maximum RCP value of 98.40 ± 0.28% (at 30 min). At 37 deg C in serum the complex showed stable behaviour up to 4 h with the appearance of 15.95% undesirable by products within 16 h of the incubation. The complex showed saturated in vitro binding with E. coli with a maximum uptake of 74.25 ± 0.50% (at 90 min). Normal biodistribution behaviour was noted with a sixfold higher accumulation in the muscle of the MWR, artificially infected with live E. coli as compared to the MWR infected with heat killed E. coli, inflamed and normal muscle. The high RCP in saline, elevated in vitro stability in serum, saturated in vitro binding with E. coli and the sixfold higher accumulation in the infected (live) muscle of the MWR as compared to the inflamed and normal muscle, recognized the aptness of the 99m Tc ≡ N-PZND complex as a prospective E. coli in vivo infection radiotracer. (author)

N,N-diethyldithiocarbamate promotes oxidative stress prior to myelin structural changes and increases myelin copper content

International Nuclear Information System (INIS)

Viquez, Olga M.; Lai, Barry; Ahn, Jae Hee; Does, Mark D.; Valentine, Holly L.; Valentine, William M.

2009-01-01

Dithiocarbamates are a commercially important class of compounds that can produce peripheral neuropathy in humans and experimental animals. Previous studies have supported a requirement for copper accumulation and enhanced lipid peroxidation in dithiocarbamate-mediated myelinopathy. The study presented here extends previous investigations in two areas. Firstly, although total copper levels have been shown to increase within the nerve it has not been determined whether copper is increased within the myelin compartment, the primary site of lesion development. Therefore, the distribution of copper in sciatic nerve was characterized using synchrotron X-ray fluorescence microscopy to determine whether the neurotoxic dithiocarbamate, N,N-diethyldithiocarbamate, increases copper levels in myelin. Secondly, because lipid peroxidation is an ongoing process in normal nerve and the levels of lipid peroxidation products produced by dithiocarbamate exposure demonstrated an unusual cumulative dose response in previous studies the biological impact of dithiocarbamate-mediated lipid peroxidation was evaluated. Experiments were performed to determine whether dithiocarbamate-mediated lipid peroxidation products elicit an antioxidant response through measuring the protein expression levels of three enzymes, superoxide dismutase 1, heme oxygenase 1, and glutathione transferase α, that are linked to the antioxidant response element promoter. To establish the potential of oxidative injury to contribute to myelin injury the temporal relationship of the antioxidant response to myelin injury was determined. Myelin structure in peripheral nerve was assessed using multi-exponential transverse relaxation measurements (MET 2 ) as a function of exposure duration, and the temporal relationship of protein expression changes relative to the onset of changes in myelin integrity were determined. Initial assessments were also performed to explore the potential contribution of dithiocarbamate

Multiblock copolymers synthesized in aqueous dispersions using multifunctional RAFT agents

NARCIS (Netherlands)

Bussels, R.; Bergman-Göttgens, C.M.; Meuldijk, J.; Koning, C.E.

2005-01-01

Triblock copolymers were synthesized in aqueous dispersions in two polymerization steps using a low molar mass difunctional dithiocarbamate-based RAFT agent, and in merely one polymerization step using a macromolecular difunctional dithiocarbamate-based RAFT agent. Segmented block copolymers

Deleterious effect of salusin-β in paraventricular nucleus on sympathetic activity and blood pressure via NF-κB signaling in a rat model of obesity hypertension.

Science.gov (United States)

Huang, Xiaodong; Wang, Yanchun; Ren, Kuang

2015-08-01

The paraventricular nucleus (PVN) has been shown to play a critical role in regulating blood pressure and sympathetic activity in obesity hypertension (OH). Salusin-β is a bioactive peptide with potential roles in mediating cardiovascular activity. The study was designed to test the hypothesis that salusin-β in the PVN can modulate sympathetic activity and blood pressure in OH. Male Sprague-Dawley rats were used to induce OH by a 12-week feeding of a high-fat diet (42% kcal as fat). Microinjection of salusin-β into the PVN increased the renal sympathetic nerve activity (RSNA), mean arterial pressure (MAP) and heart rate (HR) in a dose-dependent manner, whereas salusin-β antibody elicited significant decreases in RSNA, MAP and HR, and abolished the effects of salusin-β only in the OH rats. As expected, the OH rats had a higher norepinephrine level, which was further increased by salusin-β. Furthermore, salusin-β in the PVN accelerated the nuclear translocation of the p65 subunit of nuclear factor kappa B (NF-KB) and the degradation of IKB-α (an endogenous inhibitor of NF-KB). Pretreatment with pyrrolidine dithiocarbamate (an exogenous inhibitor of NF-KB) decreased RSNA, MAP and HR, and abolished the effects of salusin-β in the PVN in the OH rats. We concluded that salusin-β in the PVN markedly increased sympathetic outflow and blood pressure in diet-induced OH rats via NF-κB signaling.

Development of a method for multielemental determination in water by EDXRF with radioisotopic source of 238Pu

International Nuclear Information System (INIS)

Serrano, C.; Estévez, J.; Montero, A.; Pupo, I.; Herrero, Z.; Leyva, D.; Arteche, J.; Varcárcel, L.; Van Espen, P.; Santos Júnior, J. A. dos

2017-01-01

A method for determination of Cr, Fe, Co, Ni, Cu, Zn, Hg and Pb in waters by Energy Dispersive X Ray Fluorescence (EDXRF) was implemented, using a radioisotopic source of 238 Pu. For previous concentration was employed a procedure including a coprecipitation step with ammonium pyrrolidine dithiocarbamate (APDC) as quelant agent, the separation of the phases by filtration, the measurement of filter by EDXRF and quantification by a thin layer absolute method. Sensitivity curves for K and L lines were obtained respectively. The sensitivity for most elements was greater by an order of magnitude in the case of measurement with a source of 238 Pu instead of 109 Cd, which means a considerable decrease in measurement times. The influence of the concentration in the precipitation efficiency was evaluated for each element. In all cases the recoveries are close to 100%, for this reason it can be affirmed that the method of determination of the studied elements is quantitative. Metrological parameters of the method such as trueness, precision, detection limit and uncertainty were calculated. A procedure to calculate the uncertainty of the method was elaborated; the most significant source of uncertainty for the thin layer EDXRF method is associated with the determination of instrumental sensitivities. The error associated with the determination, expressed as expanded uncertainty (in %), varied from 15.4% for low element concentrations (2.5-5 μg/L) to 5.4% for the higher concentration range (20-25 μg/L). (author)

Determination of trace elements in ground water by two preconcentration methods using atomic absorption spectrometry

International Nuclear Information System (INIS)

Elhag, A. Y.

2004-01-01

This is a comparative study between two different methods of preconcentration done to separate the trace elements cadmium, nickel. chromium, manganese, copper, zinc, and lead in drinking (ground) water samples taken from different locations in Gezira State, central Sudan (the map); these methods are (coprecipitation) with aluminium hydroxide and by Ammonium Pyrrolidine Dithiocarbamate (APDC) using Methyl Isobutyl Ketone (MIBK) as an organic solvent; and subsequent analysis by Atomic Absorption Spectrometry (AAS) for both methods. The result of comparison showed the superiority of the (APDC) coprecipitation method over the aluminium hydroxide coprecipitation method in the total percentage recoveries of the studied trace elements in drinking (ground) water samples, such results confirm previous studies. This study also involves direct analysis of these water samples by atomic absorption spectrometry to determine the concentrations of trace elements Cadmium, Nickel, Chromium, Manganese, Copper, Zinc and Lead and compare it to the corresponding guide line values described by the World Health Organization and the maximum concentrations of trace elements in drinking water permitted by the Sudanese Standards and Metrology Organizations (SSMO), where the concentrations of some elements in some samples were found to be different than the described values by both of the organizations. The study includes a trial to throw light on the effect of the proximity of the water samples sources to the Blue Nile river on its trace elements concentrations; no relation was proved to exist in that respect.(Author)

SIRT1 induces resistance to apoptosis in human granulosa cells by activating the ERK pathway and inhibiting NF-κB signaling with anti-inflammatory functions.

Science.gov (United States)

Han, Ying; Luo, Haining; Wang, Hui; Cai, Jun; Zhang, Yunshan

2017-10-01

SIRT1, a member of the sirtuin family, has recently emerged as a vital molecule in controlling ovarian function. The aims of the present study were to investigate SIRT1 expression and analyze SIRT1-mediated apoptosis in human granulosa cells (GCs). Human ovarian tissues were subjected to immunohistochemistry for localization of SIRT1 expression. SIRT1 knockdown in a human ovarian GC tumor line (COV434) was achieved by small interfering RNA, and the relationship between apoptosis and SIRT1 was assessed by quantitative reverse transcription polymerase chain reaction and western blotting. We further detected SIRT1 expression in human luteinized GCs. Associations among SIRT1 knockdown, SIRT1 stimulation (resveratrol) and expression of ERK1/2 and apoptotic regulatory proteins were analyzed in cell lines and luteinized GCs. Resveratrol downregulated the levels of nuclear factor (NF)-κB/p65, but this inhibitory effect was attenuated by suppressing SIRT1 activity. The NF-κB/p65 inhibitor pyrrolidine dithiocarbamate achieved similar anti-apoptosis effects. These results suggest that SIRT1 might play an anti-apoptotic role in apoptosis processes in GCs, possibly by sensing and regulating the ERK1/2 pathway, which has important clinical implications. Thus, our study provides a mechanistic link, whereby activation of SIRT1 function might help to sustain human reproduction by maintaining GCs as well as oocytes, offering a novel approach for developing a new class of therapeutic anti-inflammatory agents.

Development of a method for multielemental determination in water by EDXRF with radioisotopic source of {sup 238}Pu

Energy Technology Data Exchange (ETDEWEB)

Serrano, C.; Estévez, J.; Montero, A.; Pupo, I.; Herrero, Z.; Leyva, D.; Arteche, J.; Varcárcel, L. [Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear (CEADEN), (Cuba); Van Espen, P. [University of Amberes, (Belgium); Santos Júnior, J. A. dos, E-mail: cserrano@cedaen.edu.cu [Universidade Federal de Pernambuco (UFPE), Recife (Brazil)

2017-07-01

A method for determination of Cr, Fe, Co, Ni, Cu, Zn, Hg and Pb in waters by Energy Dispersive X Ray Fluorescence (EDXRF) was implemented, using a radioisotopic source of {sup 238}Pu. For previous concentration was employed a procedure including a coprecipitation step with ammonium pyrrolidine dithiocarbamate (APDC) as quelant agent, the separation of the phases by filtration, the measurement of filter by EDXRF and quantification by a thin layer absolute method. Sensitivity curves for K and L lines were obtained respectively. The sensitivity for most elements was greater by an order of magnitude in the case of measurement with a source of {sup 238}Pu instead of {sup 109}Cd, which means a considerable decrease in measurement times. The influence of the concentration in the precipitation efficiency was evaluated for each element. In all cases the recoveries are close to 100%, for this reason it can be affirmed that the method of determination of the studied elements is quantitative. Metrological parameters of the method such as trueness, precision, detection limit and uncertainty were calculated. A procedure to calculate the uncertainty of the method was elaborated; the most significant source of uncertainty for the thin layer EDXRF method is associated with the determination of instrumental sensitivities. The error associated with the determination, expressed as expanded uncertainty (in %), varied from 15.4% for low element concentrations (2.5-5 μg/L) to 5.4% for the higher concentration range (20-25 μg/L). (author)

1-[2-Oxo-1′-phenyl-2′,3′,5′,6′,7′,7a'-hexahydroindoline-3-spiro-3′-1′H-pyrrolizin-2′-yl]-3-phenylprop-2-en-1-one

Directory of Open Access Journals (Sweden)

S. Sriman Narayanan

2008-09-01

Full Text Available In the title compound, C29H26N2O2, one of the pyrrolidine rings in the pyrrolizine system is disordered, with site occupancies of ca 0.55 and 0.45. Both components of the disordered pyrrolidine ring adopt envelope conformations, whereas the other pyrrolidine ring adopts a twist conformation. The molecules are linked into centrosymmetric dimers by N—H...O hydrogen bonds and the dimers are connected via C—H...π interactions.

Phase equilibrium measurements and the tuning behavior of new sII clathrate hydrates

Energy Technology Data Exchange (ETDEWEB)

Shin, Woongchul; Park, Seongmin; Ro, Hyeyoon; Koh, Dong-Yeun; Seol, Jiwoong [Department of Chemical and Biomolecular Engineering (BK21 Program), KAIST, Daejeon 305-701 (Korea, Republic of); Lee, Huen, E-mail: h_lee@kaist.ac.kr [Department of Chemical and Biomolecular Engineering (BK21 Program), KAIST, Daejeon 305-701 (Korea, Republic of); Graduate School of EEWS, KAIST, Daejeon 305-701 (Korea, Republic of)

2012-01-15

Graphical abstract: Pyrrolidine and piperidine act as sII clathrate hydrate formers under methane gas. Highlights: > New sII clathrate hydrate formers were proposed: pyrrolidine and piperidine. > Formation of gas hydrate with methane as help gas was confirmed. > NMR, Raman, and XRD patterns were analyzed to identify the hydrate structures. > We measured (L + H + V) phase equilibrium with proposed hydrate formers. > Tuning phenomena increase gas storage in (pyrrolidine + CH{sub 4}) clathrate hydrates. - Abstract: We suggest two types of new amine-type sII formers: pyrrolidine and piperidine. These guest compounds fail to form clathrate hydrate structures with host water, but instead have to combine with light gaseous guest molecules (methane) for enclathration. First, two binary clathrate hydrates of (pyrrolidine + methane) and (piperidine + methane) were synthesized at various amine concentrations. {sup 13}C NMR and Raman analysis were done to identify the clathrate hydrate structure and guest distribution over sII-S and sII-L cages. XRD was also used to find the exact structure and corresponding cell parameters. At a dilute pyrrolidine concentration of less than 5.56 mol%, the tuning phenomenon is observed such that methane molecules surprisingly occupy sII-L cages. At the critical guest concentration of about 0.1 mol%, the cage occupancy ratio reaches the maximum of approximately 0.5. At very dilute guest concentration below 0.1 mol%, the methane molecules fail to occupy large cages on account of their rarefied distribution in the network. Direct-release experiments were performed to determine the actual guest compositions in the clathrate hydrate phases. Finally, we measured the clathrate hydrate phase equilibria of (pyrrolidine + methane) and (piperidine + methane).

Phase equilibrium measurements and the tuning behavior of new sII clathrate hydrates

International Nuclear Information System (INIS)

Shin, Woongchul; Park, Seongmin; Ro, Hyeyoon; Koh, Dong-Yeun; Seol, Jiwoong; Lee, Huen

2012-01-01

Graphical abstract: Pyrrolidine and piperidine act as sII clathrate hydrate formers under methane gas. Highlights: → New sII clathrate hydrate formers were proposed: pyrrolidine and piperidine. → Formation of gas hydrate with methane as help gas was confirmed. → NMR, Raman, and XRD patterns were analyzed to identify the hydrate structures. → We measured (L + H + V) phase equilibrium with proposed hydrate formers. → Tuning phenomena increase gas storage in (pyrrolidine + CH 4 ) clathrate hydrates. - Abstract: We suggest two types of new amine-type sII formers: pyrrolidine and piperidine. These guest compounds fail to form clathrate hydrate structures with host water, but instead have to combine with light gaseous guest molecules (methane) for enclathration. First, two binary clathrate hydrates of (pyrrolidine + methane) and (piperidine + methane) were synthesized at various amine concentrations. 13 C NMR and Raman analysis were done to identify the clathrate hydrate structure and guest distribution over sII-S and sII-L cages. XRD was also used to find the exact structure and corresponding cell parameters. At a dilute pyrrolidine concentration of less than 5.56 mol%, the tuning phenomenon is observed such that methane molecules surprisingly occupy sII-L cages. At the critical guest concentration of about 0.1 mol%, the cage occupancy ratio reaches the maximum of approximately 0.5. At very dilute guest concentration below 0.1 mol%, the methane molecules fail to occupy large cages on account of their rarefied distribution in the network. Direct-release experiments were performed to determine the actual guest compositions in the clathrate hydrate phases. Finally, we measured the clathrate hydrate phase equilibria of (pyrrolidine + methane) and (piperidine + methane).

New antimony(III) halide complexes with dithiocarbamate ligands derived from thiuram degradation: The effect of the molecule's close contacts on in vitro cytotoxic activity

International Nuclear Information System (INIS)

Urgut, O.S.; Ozturk, I.I.; Banti, C.N.; Kourkoumelis, N.; Manoli, M.; Tasiopoulos, A.J.; Hadjikakou, S.K.

2016-01-01

ABSTRACT: Antimony(III) halide complexes of the formulae {[SbBr(Me 2 DTC) 2 ] n } (1), {[SbI(Me 2 DTC) 2 ] n } (2) and {[(Me 2 DTC) 2 Sb(μ 2 -I)Sb(Me 2 DTC) 2 ] + .I 3 − } (3) (Me 2 DTC = dimethyldithiocarbomate) were synthesized from SbX 3 , (X = Br or I) and tetramethylthiuram monosulfide (Me 4 tms) or tetramethylthiuram disulfide (Me 4 tds). The complexes were characterized by melting point (m.p.), elemental analysis (e.a.), Fourier-transform Infra-Red (FT-IR), Fourier-transform Raman (FT-Raman), Nuclear Magnetic Resonance ( 1 H, 13 C-NMR) spectroscopy and Thermogravimetric-Differential Thermal Analysis (TG-DTA). Crystal structures of complexes 1–3 were determined with single crystal X-ray diffraction analysis. Complexes 1 and 2 are polymers with distorted square pyramidal (SP) geometry in each monomeric unit, whereas complex 3 is ionic, containing an iodonium linkage Sb–I + –Sb and an I 3 − counter anion; to the best of our knowledge, this is the first ionic antimony(III) iodide complex. The in vitro cytotoxic activity of 1–3 against human adenocarcinoma cells: breast (MCF-7) and cervix (HeLa) cells and non-cancerous cells: MRC-5 (normal human fetal lung fibroblast cells) was evaluated with trypan blue (TB) and sulforhodamine B (SRB) assays. Among antimony(III) compounds with sulfur containing ligand, those of dithiocarbamates exhibit significant cytotoxic activity. Hirshfeld surface volumes were analyzed to clarify the nature of the intermolecular interactions by the 2D fingerprint plot. Molecules with lower H-all atoms inter-molecular interactions exhibit the higher activity against MCF-7 cells. The in vivo genotoxicity of 1–3 was evaluated by the mean of Allium cepa test. Alterations in the mitotic index values due to the chromosomal aberrations were observed in the case of complexes 2 and 3. Since, no such alteration is caused by 1, it makes this compound candidate for further study as potential drug. - Graphical abstract: The in vitro

New antimony(III) halide complexes with dithiocarbamate ligands derived from thiuram degradation: The effect of the molecule's close contacts on in vitro cytotoxic activity

Energy Technology Data Exchange (ETDEWEB)

Urgut, O.S. [Department of Chemistry, Namık Kemal University, 59030, Tekirdag (Turkey); Ozturk, I.I., E-mail: iiozturk@nku.edu.tr [Department of Chemistry, Namık Kemal University, 59030, Tekirdag (Turkey); Banti, C.N., E-mail: cbanti@cc.uoi.gr [Section of Inorganic and Analytical Chemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina (Greece); Kourkoumelis, N., E-mail: nkourkou@uoi.gr [Medical Physics Laboratory, Medical School, University of Ioannina, Ioannina, 45110 (Greece); Manoli, M.; Tasiopoulos, A.J. [Department of Chemistry, University of Cyprus, Nicosia (Cyprus); Hadjikakou, S.K., E-mail: shadjika@uoi.gr [Section of Inorganic and Analytical Chemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina (Greece)

2016-01-01

ABSTRACT: Antimony(III) halide complexes of the formulae {[SbBr(Me_2DTC)_2]_n} (1), {[SbI(Me_2DTC)_2]_n} (2) and {[(Me_2DTC)_2Sb(μ_2-I)Sb(Me_2DTC)_2]"+.I_3"−} (3) (Me{sub 2}DTC = dimethyldithiocarbomate) were synthesized from SbX{sub 3}, (X = Br or I) and tetramethylthiuram monosulfide (Me{sub 4}tms) or tetramethylthiuram disulfide (Me{sub 4}tds). The complexes were characterized by melting point (m.p.), elemental analysis (e.a.), Fourier-transform Infra-Red (FT-IR), Fourier-transform Raman (FT-Raman), Nuclear Magnetic Resonance ({sup 1}H,{sup 13}C-NMR) spectroscopy and Thermogravimetric-Differential Thermal Analysis (TG-DTA). Crystal structures of complexes 1–3 were determined with single crystal X-ray diffraction analysis. Complexes 1 and 2 are polymers with distorted square pyramidal (SP) geometry in each monomeric unit, whereas complex 3 is ionic, containing an iodonium linkage Sb–I{sup +}–Sb and an I{sub 3}{sup −} counter anion; to the best of our knowledge, this is the first ionic antimony(III) iodide complex. The in vitro cytotoxic activity of 1–3 against human adenocarcinoma cells: breast (MCF-7) and cervix (HeLa) cells and non-cancerous cells: MRC-5 (normal human fetal lung fibroblast cells) was evaluated with trypan blue (TB) and sulforhodamine B (SRB) assays. Among antimony(III) compounds with sulfur containing ligand, those of dithiocarbamates exhibit significant cytotoxic activity. Hirshfeld surface volumes were analyzed to clarify the nature of the intermolecular interactions by the 2D fingerprint plot. Molecules with lower H-all atoms inter-molecular interactions exhibit the higher activity against MCF-7 cells. The in vivo genotoxicity of 1–3 was evaluated by the mean of Allium cepa test. Alterations in the mitotic index values due to the chromosomal aberrations were observed in the case of complexes 2 and 3. Since, no such alteration is caused by 1, it makes this compound candidate for further study as potential drug. - Graphical

Predictive Direct Torque Control Application-Specific Integrated Circuit of an Induction Motor Drive with a Fuzzy Controller

Directory of Open Access Journals (Sweden)

Guo-Ming Sung

2017-06-01

Full Text Available This paper proposes a modified predictive direct torque control (PDTC application-specific integrated circuit (ASIC of a motor drive with a fuzzy controller for eliminating sampling and calculating delay times in hysteresis controllers. These delay times degrade the control quality and increase both torque and flux ripples in a motor drive. The proposed fuzzy PDTC ASIC calculates the stator’s magnetic flux and torque by detecting the three-phase current, three-phase voltage, and rotor speed, and eliminates the ripples in the torque and flux by using a fuzzy controller and predictive scheme. The Verilog hardware description language was used to implement the hardware architecture, and the ASIC was fabricated by the Taiwan Semiconductor Manufacturing Company through a 0.18-μm 1P6M CMOS process that involved a cell-based design method. The measurements revealed that the proposed fuzzy PDTC ASIC of the three-phase induction motor yielded a test coverage of 96.03%, fault coverage of 95.06%, chip area of 1.81 × 1.81 mm2, and power consumption of 296 mW, at an operating frequency of 50 MHz and a supply voltage of 1.8 V.

3-(4-Fluorophenyl-1-[1′-(4-fluorophenyl-2-oxo-5′,6′,7′,7a′-tetrahydro-1H-indole-3(2H-spiro-3′(2′H-1H′-pyrrolizin-2′-yl]prop-2-en-1-one

Directory of Open Access Journals (Sweden)

S. Sriman Narayanan

2008-09-01

Full Text Available In the title compound, C29H24F2N2O2, one of the pyrrolidine rings of the pyrrolizine system is disordered over two sites, with occupancy factors 0.734:0.266 (12. Both components of the disordered pyrrolidine ring adopt envelope conformations, whereas the other pyrrolidine ring adopts a twist conformation. The molecules are linked into centrosymmetric dimers by N—H...O hydrogen bonds and the dimers are connected via C—H...π interactions. The crystal structure is also stabilized by intermolecular C—H...F hydrogen bonds.

Csbnd H⋯Ni and Csbnd H⋯π(chelate) interactions in nickel(II) complexes involving functionalized dithiocarbamates and triphenylphosphine

Science.gov (United States)

Sathiyaraj, E.; Thirumaran, S.; Selvanayagam, S.; Sridhar, B.; Ciattini, Samuele

2018-05-01

New bis(N-benzyl-N-substituted benzyldithiocarbamato-S,S‧)nickel(II) (1-3) and (N-benzyl-N-substituted benzyldithiocarbamato-S,S‧)(isothiocyanato-N)- (triphenylphosphane)nickel(II) (4-6) [where substituted benzyl = 2-HOsbnd C6H4sbnd CH2sbnd (1,4), 3-HOsbnd C6H4sbnd CH2sbnd (2,5), 4-Fsbnd C6H4sbnd CH2sbnd (3,6)] were synthesized and characterized using IR, electronic, and NMR (1H and 13C) spectra. X-ray structural analysis of homoleptic complex (1) and heteroleptic complexes (5 and 6) confirmed the presence of four coordinated nickel in a distorted square planar arrangement with NiS4 and NiS2PN chromophores, respectively. The νC-S stretching vibrations are observed around 990 cm-1 without any splitting supporting the bidentate coordination of the dithiocarbamate ligand. Electronic spectral studies of all the complexes (1-6) indicate that the geometry of the nickel atom is probably square planar. NMR spectra of all homoleptic and heteroleptic complexes (1-6) reveal a weak signal associated with the backbone carbon (N13CS2) in the region 204.0-210.0 ppm with a weak intensity characteristic of the quaternary carbon signals. The greater trans influence of triphenylphosphine in complexes 5 and 6 is supported by the long Nisbnd S distance compared to other Nisbnd S distance which is opposite to the NCS- ligand. In the structure of complex 5, C-H⋯π(chelate) interactions results in polymeric chain. Both structures show intramolecular Ni⋯H interactions but that on 6 is the strongest. C-H⋯π interactions are also found in 1, 5 and 6. Hirshfeld surface analysis and the associated 2D fingerprint plots of 1, 5 and 6 have been studied to evaluate intermolecular interactions. The molecular geometries of complexes 1, 5 and 6 have been optimized by abinitio HF method using LANL2DZ program.

Single-crystal-to-single-crystal transformation and solvochromic luminescence of a dinuclear gold(I)-(aza-[18]crown-6)dithiocarbamate compound.

Science.gov (United States)

Tzeng, Biing-Chiau; Chao, An

2015-01-26

The treatment of [AuCl(SMe2 )] with an equimolar amount of NaO5 NCS2 (O5 NCS2 =(aza-[18]crown-6)dithiocarbamate) in CH3 CN gave [Au2 (O5 NCS2 )2 ]⋅2 CH3 CN (2⋅2 CH3 CN), and its crystal structure displays a dinuclear gold(I)-azacrown ether ring and an intermolecular gold(I)⋅⋅⋅gold(I) contact of 2.8355(3) Å in crystal lattices. It is noted that two other single crystals of 2⋅tert-butylbenzene⋅H2 O and 2⋅0.5 m-xylene can be successfully obtained from a single-crystal-to-single-crystal (SCSC) transformation process by immersing single crystals of 2⋅2 CH3 CN in the respective solvents, and both also show intermolecular gold(I)⋅⋅⋅gold(I) contacts of 2.9420(5) and 2.890(2)-2.902(2) Å, respectively. Significantly, the emissions of all three 2⋅solvates are well correlated with their respective intermolecular gold(I)⋅⋅⋅gold(I) contacts, where such contacts increase with 2⋅2 CH3 CN (2.8355(3) Å)energies increase with 2⋅2 CH3 CN (602 nm)<2⋅0.5 m-xylene (583 nm)<2⋅tert-butylbenzene⋅H2 O (546 nm) as well. In this regard, we further examine the solvochromic luminescence for some other aromatics, and finally their emissions are within 546-602 nm. Obviously, the above results are mostly ascribed to the occurrence of intermolecular gold(I)⋅⋅⋅gold(I) contacts in 2⋅solvates, which are induced by the presence of various solvates in the solid state, as a key role to be responsible for their solvochromic luminescence. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Neutral and stereospecific Tc-99m complexes: [99mTc]N-benzyl-3,4-di-(N-2-mercaptoethyl)-amino-pyrrolidines (P-BAT)

International Nuclear Information System (INIS)

Zhuang Zhiping; Ploessl, Karl; Kung Meiping; Mu Mu; Kung, Hank F.

1999-01-01

Technetium-99m-labeled radiopharmaceuticals are currently the most commonly used agents in nuclear medicine. To prepare binding site-specific small molecules containing a Tc-99m complexing core, it is important to consider a ligand system, which selectively forms only one stereoisomer. A novel series of bisaminoethanethiol (BAT) derivatives as a model system were prepared. Stereoisomers of N-benzyl-3,4-di-(N-2-mercaptoethyl)-amino pyrrolidines (P-BAT): (3R,4R)-P-BAT (R,R-4) and (3,4)meso-P-BAT (8), the trans and meso isomer, respectively, as a chelating group were prepared successfully. The desired Tc-99m P-BAT complexes were obtained by using Sn(II)/glucoheptonate as the reducing agent for [ 99m Tc]pertechnetate. As predicted, after complexation with [ 99m Tc]Tc v O, the trans isomer, (3R,4R)-P-BAT (R,R-4), showed only one isomer; whereas the corresponding meso isomer, (3,4)meso-P-BAT (8), produced two distinctive complexes isolated readily by high performance liquid chromatography (HPLC). The [ 99m Tc](R,S)meso-P-BAT (8) isomers showed a different lipophilicity (partition coefficient [P.C.]=54.3 and 55.4 for peak A and peak B, respectively), as compared with that of the corresponding [ 99m Tc](3R,4R)-P-BAT (R,R-4), trans isomer ( P.C.=163). Results of the biodistribution study in rats of these isomers show different heart and brain uptake, suggesting that the intrinsic differences in biodistribution are due to structural and stereospecific factors. Examples in this report confirm that it is possible to design stereospecific Tc-99m complexes based on the bisaminoethanethiol (N 2 S 2 , BAT) ligand system. Consideration on stereoselectivity of site-specific agents labeled with Tc-99m is likely an essential requirement on developing binding-site specific radiopharmaceuticals

Aggregation behavior of gemini pyrrolidine-based ionic liquids 1,1'-(butane-1,4-diyl)bis(1-alkylpyrrolidinium) bromide ([C(n)py-4-C(n)py][Br2]) in aqueous solution.

Science.gov (United States)

Zhang, Shaohua; Yan, Han; Zhao, Mingwei; Zheng, Liqiang

2012-04-15

Three gemini pyrrolidine-based ionic liquids, 1,1'-(butane-1,4-diyl)bis(1-alkylpyrrolidinium) bromide ([C(n)py-4-C(n)py][Br(2)], n=10, 12, 14), were synthesized. Their aggregation behavior in aqueous solution was systematically investigated by surface tension, electrical conductivity, and steady-state fluorescence. Compared with their corresponding monomers, N-alkyl-N-methylpyrrolidinium bromide (C(n)MPB), [C(n)py-4-C(n)py][Br(2)], have higher surface activity. The special structure of [C(n)py-4-C(n)py][Br(2)] that has a spacer in their hydrophilic head groups results in a lower surface excess concentration (Γ(max)) and a larger molecular cross-sectional area (A(min)). Electrical conductivity studies show a lower degree of counter-ion binding to the aggregates. A smaller aggregation number (N(agg)) is observed by the pyrene fluorescence quenching method. A series of thermodynamic parameters (ΔG(agg)(0),ΔH(agg)(0),-TΔS(agg)(0)) of aggregation derived from electrical conductivity indicate that the aggregation of [C(n)py-4-C(n)py][Br(2)] is enthalpy-driven, while aggregation of C(n)MPB is entropy-driven at low temperatures but enthalpy-driven at high temperatures. Copyright © 2012 Elsevier Inc. All rights reserved.

Development of new portable miniaturize solid phase microextraction of silver-APDC complex using micropipette tip in-syringe system couple with electrothermal atomic absorption spectrometry

Science.gov (United States)

Naeemullah; Kazi, Tasneem Gul; Afridi, Hassan Imran; Shah, Faheem; Arain, Sadaf Sadia; Arain, Salma Aslam; Panhwar, Abdul Haleem; Arain, Mariam Shahzadi; Samoon, Muhammad Kashif

2016-02-01

An innovative and simple miniaturized solid phase microextraction (M-SPME) method, was developed for preconcentration and determination of silver(I) in the fresh and waste water samples. For M-SPME, a micropipette tip packed with activated carbon cloth (ACC) as sorbent, in a syringe system. The size, morphology and elemental composition of ACC before and after adsorption of analyte have been characterized by scanning electron microscopy and energy dispersive spectroscopy. The sample solution treated with a complexing reagent, ammonium pyrrolidine dithiocarbamate (APDC), was drawn into the syringe filled with ACC and dispensed manually for 2 to 10 aspirating/dispensing cycle. Then the Ag- complex sorbed on the ACC in micropipette was quantitatively eluted by drawing and dispensing of different concentrations of acids for 2 to 5 aspirating/dispensing cycles. The extracted Ag ions with modifier were injected directly into the electrothermal atomic absorption spectrometry for analysis. The influence of different variables on the extraction efficiency, including the concentration of ligand, pH, sample volume, eluent type, concentration and volume was investigated. Validity and accuracy of the developed method was checked by the standard addition method. Reliability of the proposed methodology was checked by the relative standard deviation (%RSD), which was found to be < 5%. Under the optimized experimental variables, the limits of detection (LOD) and enhancement factors (EF), were obtained to be 0.86 ng L- 1 and 120, respectively. The proposed method was successfully applied for the determination of trace levels of silver ions in fresh and waste water samples.

Lipopolysaccharide stimulates endogenous β-glucuronidase via PKC/NF-κB/c-myc signaling cascade: a possible factor in hepatolithiasis formation.

Science.gov (United States)

Yao, Dianbo; Dong, Qianze; Tian, Yu; Dai, Chaoliu; Wu, Shuodong

2017-11-29

Hepatolithiasis is commonly encountered in Southeastern and Eastern Asian countries, but the pathogenesis mechanism of stone formation is still not well understood. Now, the role of endogenous β-glucuronidase in pigment stones formation is being gradually recognized. In this study, the mechanism of increased expression and secretion of endogenous β-glucuronidase during hepatolithiasis formation was investigated. We assessed the endogenous β-glucuronidase, c-myc, p-p65, and p-PKC expression in liver specimens with hepatolithiasis by immunohistochemical staining, and found that compared with that in normal liver samples, the expression of endogenous β-glucuronidase, c-myc, p-p65, and p-PKC in liver specimens with hepatolithiasis significantly increased, and their expressions were positively correlated with each other. Lipopolysaccharide (LPS) induced increased expression of endogenous β-glucuronidase and c-myc in hepatocytes and intrahepatic biliary epithelial cells in a dose- and time-dependent manner, and endogenous β-glucuronidase secretion increased, correspondingly. C-myc siRNA transfection effectively inhibited the LPS-induced expression of endogenous β-glucuronidase. Furthermore, NF-κB inhibitor pyrrolidine dithiocarbamate or PKC inhibitor chelerythrine could effectively inhibit the LPS-induced expression of c-myc and endogenous β-glucuronidase, and the expression of p-p65 was also partly inhibited by chelerythrine. Our clinical observations and experimental data indicate that LPS could induce the increased expression and secretion of endogenous β-glucuronidase via a signaling cascade of PKC/NF-κB/c-myc in hepatocytes and intrahepatic biliary epithelial cells, and endogenous β-glucuronidase might play a possible role in the formation of hepatolithiasis.

Cytotoxicity and apoptotic inducibility of Vitex agnus-castus fruit extract in cultured human normal and cancer cells and effect on growth.

Science.gov (United States)

Ohyama, Kunio; Akaike, Takenori; Hirobe, Chieko; Yamakawa, Toshio

2003-01-01

A crude extract was prepared with ethanol from dried ripened Vitex agnus-castus fruits growing in Israel (Vitex extract). Cytotoxicity of the extract against human uterine cervical canal fibroblast (HCF), human embryo fibroblast (HE-21), ovarian cancer (MCF-7), cervical carcinoma (SKG-3a), breast carcinoma (SKOV-3), gastric signet ring carcinoma (KATO-III), colon carcinoma (COLO 201), and small cell lung carcinoma (Lu-134-A-H) cells was examined. After culture for 24 h (logarithmic growth phase) or 72 h (stationary growth phase), the cells were treated with various concentrations of Vitex extract. In both growth phases, higher growth activity of cells and more cytotoxic activity of Vitex extract were seen. The cytotoxic activity against stationary growth-phase cells was less than that against logarithmic growth-phase cells. DNA fragmentation of Vitex extract-treated cells was seen in SKOV-3, KATO-III, COLO 201, and Lu-134-A-H cells. The DNA fragmentation in Vitex extract-treated KATO-III cells was inhibited by the presence of the antioxidative reagent pyrrolidine dithiocarbamate or N-acetyl-L-cysteine (NAC). Western blotting analysis showed that in Vitex extract-treated KATO-III cells, the presence of NAC also inhibited the expression of heme oxygenase-1 and the active forms of caspases-3, -8 and -9. It is concluded that the cytotoxic activity of Vitex extract may be attributed to the effect on cell growth, that cell death occurs through apoptosis, and that this apoptotic cell death may be attributed to increased intracellular oxidation by Vitex extract treatment.

On-line liquid phase micro-extraction based on drop-in-plug sequential injection lab-at-valve platform for metal determination

Energy Technology Data Exchange (ETDEWEB)

Mitani, Constantina [Laboratory of Analytical Chemistry, Department of Chemistry, Aristotle University, Thessaloniki 54124 (Greece); Anthemidis, Aristidis N., E-mail: anthemid@chem.auth.gr [Laboratory of Analytical Chemistry, Department of Chemistry, Aristotle University, Thessaloniki 54124 (Greece)

2013-04-10

Highlights: ► Drop-in-plug micro-extraction based on SI-LAV platform for metal preconcentration. ► Automatic liquid phase micro-extraction coupled with FAAS. ► Organic solvents with density higher than water are used. ► Lead determination in environmental water and urine samples. -- Abstract: A novel automatic on-line liquid phase micro-extraction method based on drop-in-plug sequential injection lab-at-valve (LAV) platform was proposed for metal preconcentration and determination. A flow-through micro-extraction chamber mounted at the selection valve was adopted without the need of sophisticated lab-on-valve components. Coupled to flame atomic absorption spectrometry (FAAS), the potential of this lab-at-valve scheme is demonstrated for trace lead determination in environmental and biological water samples. A hydrophobic complex of lead with ammonium pyrrolidine dithiocarbamate (APDC) was formed on-line and subsequently extracted into an 80 μL plug of chloroform. The extraction procedure was performed by forming micro-droplets of aqueous phase into the plug of the extractant. All critical parameters that affect the efficiency of the system were studied and optimized. The proposed method offered good performance characteristics and high preconcentration ratios. For 10 mL sample consumption an enhancement factor of 125 was obtained. The detection limit was 1.8 μg L{sup −1} and the precision expressed as relative standard deviation (RSD) at 50.0 μg L{sup −1} of lead was 2.9%. The proposed method was evaluated by analyzing certified reference materials and applied for lead determination in natural waters and urine samples.

Development of new portable miniaturize solid phase microextraction of silver-APDC complex using micropipette tip in-syringe system couple with electrothermal atomic absorption spectrometry.

Science.gov (United States)

Naeemullah; Kazi, Tasneem Gul; Afridi, Hassan Imran; Shah, Faheem; Arain, Sadaf Sadia; Arain, Salma Aslam; Panhwar, Abdul Haleem; Arain, Mariam Shahzadi; Samoon, Muhammad Kashif

2016-02-05

An innovative and simple miniaturized solid phase microextraction (M-SPME) method, was developed for preconcentration and determination of silver(I) in the fresh and waste water samples. For M-SPME, a micropipette tip packed with activated carbon cloth (ACC) as sorbent, in a syringe system. The size, morphology and elemental composition of ACC before and after adsorption of analyte have been characterized by scanning electron microscopy and energy dispersive spectroscopy. The sample solution treated with a complexing reagent, ammonium pyrrolidine dithiocarbamate (APDC), was drawn into the syringe filled with ACC and dispensed manually for 2 to 10 aspirating/dispensing cycle. Then the Ag- complex sorbed on the ACC in micropipette was quantitatively eluted by drawing and dispensing of different concentrations of acids for 2 to 5 aspirating/dispensing cycles. The extracted Ag ions with modifier were injected directly into the electrothermal atomic absorption spectrometry for analysis. The influence of different variables on the extraction efficiency, including the concentration of ligand, pH, sample volume, eluent type, concentration and volume was investigated. Validity and accuracy of the developed method was checked by the standard addition method. Reliability of the proposed methodology was checked by the relative standard deviation (%RSD), which was found to be <5%. Under the optimized experimental variables, the limits of detection (LOD) and enhancement factors (EF), were obtained to be 0.86 ng L(-1) and 120, respectively. The proposed method was successfully applied for the determination of trace levels of silver ions in fresh and waste water samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Organotin(IV complexes derived from N-ethyl-N-phenyldithiocarbamate: Synthesis, characterization and thermal studies

Directory of Open Access Journals (Sweden)

Jerry O. Adeyemi

2018-05-01

Full Text Available Organotin(IV dithiocarbamate complexes, RSnClL2 and R2SnL2 (R = Me, Bu, Ph, and L = N-ethyl-N-phenyldithiocarbamate, have been synthesized by the reaction of mono- and disubstituted organotin(IV with ammonium dithiocarbamate. The complexes were characterized by elemental analyses, and spectroscopic techniques (1H, 13C NMR and FTIR. The structures of Me2SnL2 and Bu2SnL2 were further established by single crystal X-ray diffraction technique. The crystal structure analysis showed that both complexes (Me2SnL2 and Bu2SnL2 exist as monomers. One of the dithiocarbamate ligands formed a chelate, while the other dithiocarbamate bonded to the central tin atom through one of the sulfur atoms and the second sulfur atom existed as a pendant to form distorted trigonal bipyramidal geometry. The thermal stability of all the complexes was studied using simultaneous thermogravimetry (TG and differential scanning calorimetry (DSC. The TG-DSC results showed that Me2SnL2, BuSnClL2, Bu2SnL2, and PhSnClL2 displayed similar decomposition pathway via isothiocyanate intermediate, while MeSnClL2 and Ph2SnL2 showed decomposition pathways different from the rest of the complexes. All the complexes resulted in SnS as the final product of the thermal decomposition process. Keywords: Organotin, Dithiocarbamate, Crystal structure, Thermal studies

Photodynamic Therapy Plus Chemotherapy Compared with Photodynamic Therapy Alone in Hilar Nonresectable Cholangiocarcinoma.

Science.gov (United States)

Wentrup, Robert; Winkelmann, Nicola; Mitroshkin, Andrey; Prager, Matthias; Voderholzer, Winfried; Schachschal, Guido; Jürgensen, Christian; Büning, Carsten

2016-05-23

Standard treatments are not available for hilar nonresectable cholangiocarcinoma (NCC). It is unknown whether combination therapy of photodynamic therapy (PDT) plus systemic chemotherapy is superior to PDT alone. We retrospectively reviewed 68 patients with hilar NCC treated with either PDT plus chemotherapy (PTD-C) or PDT monotherapy (PDT-M). The primary endpoint was the mean overall survival rate. Secondary endpoints included the 1-year survival rate, risk of cholangitic complications, and outcomes, which were evaluated according to the chemotherapy protocol. More than 90% of the study population had advanced hilar NCC Bismuth type III or IV. In the PDT-M group (n=35), the mean survival time was 374 days compared with 520 days in the PDT-C group (n=33, p=0.021). The 1-year survival rate was significantly higher in the PDT-C group compared with the PDT-M group (88% vs 58%, p=0.001) with a significant reduction of mortality (hazard ratio, 0.20; 95% confidence interval, 0.07 to 0.58; p=0.003). Gemcitabine monotherapy resulted in a shorter survival time compared with the gemcitabine combination therapy (mean, 395 days vs 566 days; p=0.09). Cholangitic complications were observed at a similar frequency in the PDT-C and PDT-M groups. Combining repeated PDT with a gemcitabine-based combination therapy might offer a significant survival benefit in patients with hilar NCC.

A scanning tunneling microscopy investigation of the phases formed by the sulfur adsorption on Au(100) from an alkaline solution of 1,4-piperazine(bis)-dithiocarbamate of potassium

Energy Technology Data Exchange (ETDEWEB)

Martínez, Javier A. [Instituto de Ciencia y Tecnología de Materiales (IMRE), Universidad de La Habana, Zapata y G, El Vedado, Plaza de la Revolución, La Habana 10400 (Cuba); Valenzuela B, José [Centro de Nanociencias y Nanotecnología (CNyN), Universidad Nacional Autónoma de México (UNAM) , km 107 Carretera Tijuana-Ensenada, Ensenada, BC 22860 (Mexico); Cao Milán, R. [Facultad de Química, Universidad de La Habana, Zapata y G, El Vedado, Plaza de la Revolución, La Habana 10400 (Cuba); Herrera, José [Instituto de Ciencia y Tecnología de Materiales (IMRE), Universidad de La Habana, Zapata y G, El Vedado, Plaza de la Revolución, La Habana 10400 (Cuba); Farías, Mario H. [Centro de Nanociencias y Nanotecnología (CNyN), Universidad Nacional Autónoma de México (UNAM) , km 107 Carretera Tijuana-Ensenada, Ensenada, BC 22860 (Mexico); Hernández, Mayra P., E-mail: mayrap@fisica.uh.cu [Instituto de Ciencia y Tecnología de Materiales (IMRE), Universidad de La Habana, Zapata y G, El Vedado, Plaza de la Revolución, La Habana 10400 (Cuba)

2014-11-30

Highlights: • New phases of sulfur on gold: hexamer and (√(2)×√(2)) were observed by STM. • Hexamers and (√(2)×√(2)) structures coexist with well-known octomers. • Formation of sulfur multilayer by K{sub 2}DTC{sub 2}pz hydrolysis under alkaline condition. • Top octomer layer have dynamic behavior while (√(2)×√(2)) and hexamer were static. • A model is presented to explain sulfur multilayer formation on Au(100). - Abstract: Piperazine-dithiocarbamate of potassium (K{sub 2}DTC{sub 2}pz) was used as a new precursor for the spontaneous deposition of sulfur on the Au(100) surface in alkaline solution. Two new sulfur phases were studied by scanning tunneling microscopy (STM). These phases were formed by six sulfur atoms (S{sub 6} phase, hexamer) and by four sulfur atoms (S{sub 4} phase, tetramer with (√(2)×√(2)) structure), and they were observed in coexistence with the well-known quasi-square patterns formed by eight sulfur atoms (S{sub 8} phase, octomer). A model was proposed where sulfur multilayers were formed by a (√(2)×√(2)) phase adsorbed directly on the gold surface while one of the other structures: hexamers or octomers were deposited on top. Sulfur layers were formed on gold terraces, vacancies and islands produced by lifting reconstructed surface. Sequential high-resolution STM images allowed the direct observation of the dynamic of the octomers, while the (√(2)×√(2)) structure remained static. Images also showed the reversible association/dissociation of the octomer.

A scanning tunneling microscopy investigation of the phases formed by the sulfur adsorption on Au(100) from an alkaline solution of 1,4-piperazine(bis)-dithiocarbamate of potassium

International Nuclear Information System (INIS)

Martínez, Javier A.; Valenzuela B, José; Cao Milán, R.; Herrera, José; Farías, Mario H.; Hernández, Mayra P.

2014-01-01

Highlights: • New phases of sulfur on gold: hexamer and (√(2)×√(2)) were observed by STM. • Hexamers and (√(2)×√(2)) structures coexist with well-known octomers. • Formation of sulfur multilayer by K 2 DTC 2 pz hydrolysis under alkaline condition. • Top octomer layer have dynamic behavior while (√(2)×√(2)) and hexamer were static. • A model is presented to explain sulfur multilayer formation on Au(100). - Abstract: Piperazine-dithiocarbamate of potassium (K 2 DTC 2 pz) was used as a new precursor for the spontaneous deposition of sulfur on the Au(100) surface in alkaline solution. Two new sulfur phases were studied by scanning tunneling microscopy (STM). These phases were formed by six sulfur atoms (S 6 phase, hexamer) and by four sulfur atoms (S 4 phase, tetramer with (√(2)×√(2)) structure), and they were observed in coexistence with the well-known quasi-square patterns formed by eight sulfur atoms (S 8 phase, octomer). A model was proposed where sulfur multilayers were formed by a (√(2)×√(2)) phase adsorbed directly on the gold surface while one of the other structures: hexamers or octomers were deposited on top. Sulfur layers were formed on gold terraces, vacancies and islands produced by lifting reconstructed surface. Sequential high-resolution STM images allowed the direct observation of the dynamic of the octomers, while the (√(2)×√(2)) structure remained static. Images also showed the reversible association/dissociation of the octomer

Biodegradation of Chlorinated Solvents: Reactions near DNAPL and Enzyme Function

Energy Technology Data Exchange (ETDEWEB)

McCarty, P. L.; Spormann, Alfred M.; Criddle, Craig, S.

2003-12-11

three to five times, leading to a more rapid clean-up of the DNAPL zone. The most favored electron donor to add is one which partitions well with the chlorinated solvent or can be concentrated near it. Unfortunately, an ideal electron donor, such as vegetable oil, is difficult to introduce and mix with DNAPL in the ground, doing this properly remains an engineering challenge. Numerical model studies have indicated that several factors may significantly influence the rate and extent of enhancement, including the inhibitory effects of PCE and cDCE, the level of ED concentration, DNAPL configuration, and competition for ED. Such factors need to be considered when contemplating engineered DNAPL bioremediation. Pseudomonas stuzeri KC is an organism that transforms CT to carbon dioxide and chloride without the formation of the hazardous intermediate, chloroform. This is accomplished by production and secretion of a molecule called PDTC. This study was direct ed towards determining how PDTC works. Cu (II) at a ratio of 1:1 Cu to PDTC was found to result in the most rapid CT transformation, confirming that the PDTC-Cu complex is both a reactant and a catalyst in CT transformation. CT degradation requires that the PDTC be in a reduced form, which is generated by contact with cell components. Fe(II) inhibits CT transformation by PDTC. Studies indicated that this inhibition is enhanced by some compound or factor in the supernatant with molecular weight greater than 10,000 Da. We have made progress in determining what this factor might be, but have not yet been able to identify it. In related studies, we found that CT transformation by another organism, Shewanella oneidensis MR1, also involves an excreted factor, but this factor is different from PDTC and results in chloroform transformation as an intermediate. Our studies have indicated that this factor is similar to vitamin K2, and we have also confirmed that vitamin K2 does transform C T into chloroform.

Biodegradation of Chlorinated Solvents: Reactions near DNAPL and Enzyme Function

International Nuclear Information System (INIS)

McCarty, P. L.; Spormann, Alfred M.; Criddle, Craig S.

2003-01-01

three to five times, leading to a more rapid clean-up of the DNAPL zone. The most favored electron donor to add is one which partitions well with the chlorinated solvent or can be concentrated near it. Unfortunately, an ideal electron donor, such as vegetable oil, is difficult to introduce and mix with DNAPL in the ground, doing this properly remains an engineering challenge. Numerical model studies have indicated that several factors may significantly influence the rate and extent of enhancement, including the inhibitory effects of PCE and cDCE, the level of ED concentration, DNAPL configuration, and competition for ED. Such factors need to be considered when contemplating engineered DNAPL bioremediation. Pseudomonas stuzeri KC is an organism that transforms CT to carbon dioxide and chloride without the formation of the hazardous intermediate, chloroform. This is accomplished by production and secretion of a molecule called PDTC. This study was direct ed towards determining how PDTC works. Cu (II) at a ratio of 1:1 Cu to PDTC was found to result in the most rapid CT transformation, confirming that the PDTC-Cu complex is both a reactant and a catalyst in CT transformation. CT degradation requires that the PDTC be in a reduced form, which is generated by contact with cell components. Fe(II) inhibits CT transformation by PDTC. Studies indicated that this inhibition is enhanced by some compound or factor in the supernatant with molecular weight greater than 10,000 Da. We have made progress in determining what this factor might be, but have not yet been able to identify it. In related studies, we found that CT transformation by another organism, Shewanella oneidensis MR1, also involves an excreted factor, but this factor is different from PDTC and results in chloroform transformation as an intermediate. Our studies have indicated that this factor is similar to vitamin K2, and we have also confirmed that vitamin K2 does transform C T into chloroform

Soil-dithiocarbamate interactions

International Nuclear Information System (INIS)

Raghu, K.

1980-01-01

Soil is the ultimate repository of the pesticides applied for the control of plant pests and diseases. A variety of interactions like leaching, adsorption, chemical and microbial degradation etc take place between soil and pesticide. Results on work on two dialkyldithiocarbamates viz. thiram (tetramethylthiuram disulfide) and ziram (zinc dimethyldithiocarbamate) with respect to above interactions in soil are discussed and summarised. 35 S-labelled thiram and ziram were used in the studies. (author)

Trace and ultratrace determination of heavy metal ions by energy-dispersive X-ray fluorescence spectrometry using graphene as solid sorbent in dispersive micro solid-phase extraction

Energy Technology Data Exchange (ETDEWEB)

Kocot, Karina; Sitko, Rafal, E-mail: rafal.sitko@us.edu.pl

2014-04-01

In this paper, the adsorptive properties of graphene nanosheets were used for simultaneous preconcentration of cobalt, nickel, copper and lead ions from water samples. The developed methodology is based on dispersive micro-solid phase extraction (DMSPE) which is miniaturized and a simplified version of classical solid phase extraction technique. In proposed procedure only 200 μL of suspension containing graphene (0.2 mg), ammonium pyrrolidine dithiocarbamate (APDC) (0.8 mg) and Triton-X-100 (0.1 mg) is rapidly injected to 50 mL of water sample. Then, graphene nanosheets with adsorbed metal-APDC chelates are collected on membrane filter and measured using energy-dispersive X-ray fluorescence (EDXRF) spectrometry. The various parameters including pH, amount of APDC, sample volume, amount of Triton-X-100 and sorption time were optimized in order to obtain the best recoveries. The experiment shows that Co, Ni, Cu and Pb can be simultaneously preconcentrated at pH of 5 with high recoveries (97%, 96%, 99% and 96% for Co, Ni, Cu and Pb, respectively) and very good precision (RSDs within 2.6–3.4%). Due to the excellent enrichment factors ranging from 400 to 2500 the proposed DMSPE–EDXRF procedure offers low detection limits. For optimized measurement conditions (voltage and current of X-ray tube, primary beam filter) the detection limits are even 0.08, 0.07, 0.08 and 0.20 ng mL{sup −1} for Co, Ni, Cu and Pb, respectively. - Highlights: • Excellent detection limits using EDXRF • A new preconcentration procedure combining DMSPE and EDXRF measurement • Graphene as a promising and efficient solid sorbent in DMSPE • Simple, fast, inexpensive and environmental friendly method.

Water analysis in Londrina, PR, using a portable EDXRF system

International Nuclear Information System (INIS)

Melquiades, Fabio L.; Silva, Wislley D.; Parreira, Paulo S.; Lopes, Fabio; Appoloni, Carlos R.

2009-01-01

The use of Energy Dispersive X-Ray Fluorescence (EDXRF) for analysis of environmental samples has gained expressive attention in the last years. With the objective of identification and quantification of heavy metals in water, EDXRF methodology with portable equipment was employed. The work consisted on the use of a portable EDXRF system constituted by a X-ray tube to excite the samples, a Si-Pin detector, a holder for the excitation-detection system and samples positioning, with the standard data acquisition electronics to register the spectra. The samples were filtered in ester cellulose membranes for suspended particulate matter retention. After this, Ammonium Pyrrolidine Dithiocarbamate (APDC) precipitation methodology was applied for sample preconcentration with posterior filtering in membranes. So, the dissolved and non dissolved metal fractions were determined separately. The detection limits were, in mg L -1 : 0.006 (Fe), 0.015 (Co), 0.004 (Cu), 0.002 (Zn), 0.004 (Se) and 0.005 (Pb), with 5% deviations for 95% of confidence. Considering all the sampling locations, it was possible to quantify the following range of concentrations, in mg L -1 : Ca (0.043 - 0.021), Ti (0.137 - 0.014), Mn (0.052 - 0.008), Fe (1.66 - 0.035), Ni (0.012 - 0.010), Cu (0.010 - 0.007), Zn (0.070 - 0.007) and Pb (0.85 - 1.01). The results presented relative deviation from 5% to 22%, within 95% of confidence level, which is considered very satisfactory when using portable equipment. In 4 h of field work it was possible to filter 14 membranes and measure around 16 samples. (author)

Di-tert-butyl-chlorido(N,N-dibenzyl-dithio-carbamato)tin(IV).

Science.gov (United States)

Abdul Muthalib, Amirah Faizah; Baba, Ibrahim; Mohamed Tahir, Mohamed Ibrahim; Tiekink, Edward R T

2011-02-26

The Sn(IV) atom in the title diorganotin dithio-carbamate, [Sn(C(4)H(9))(2)(C(15)H(14)NS(2))Cl], is penta-coordinated by an asymmetrically coordinating dithio-carbamate ligand, a Cl atom and two C atoms of the Sn-bound tert-butyl groups. The resulting C(2)ClS(2) donor set defines a coordination geometry inter-mediate between square pyramidal and trigonal bipyramidal with a slight tendency towards the former.

Isomers and conformational barriers of gas phase nicotine, nornicotine and their protonated forms

Energy Technology Data Exchange (ETDEWEB)

Yoshida, Tomoki; Farone, William A.; Xantheas, Sotiris S.

2014-07-17

We report extensive conformational searches of the neutral nicotine, nornicotine and their protonated analogs that are based on ab-initio second order Møller-Plesset perturbation (MP2) electronic structure calculations. Initial searches were performed with the 6-31G(d,p) and the energetics of the most important structures were further refined from geometry optimizations with the aug-cc-pVTZ basis set. Based on the calculated free energies at T=298 K for the gas phase molecules, neutral nicotine has two dominant trans conformers, whereas neutral nornicotine is a mixture of several conformers. For nicotine, the protonation on both the pyridine and the pyrrolidine sites is energetically competitive, whereas nornicotine prefers protonation on the pyridine nitrogen. The protonated form of nicotine is mainly a mixture of two pyridine-protonated trans conformers and two pyrrolidine-protonated trans conformers, whereas the protonated form of nornicotine is a mixture of four pyridine-protonated trans conformers. Nornicotine is conformationally more flexible than nicotine, however it is less protonated at the biologically important pyrrolidine nitrogen site. The lowest energy isomers for each case were found to interconvert via low (< 6 kcal/mol) rotational barriers around the pyridine-pyrrolidine bond.

Comparing outcomes in poorly-differentiated versus anaplastic thyroid cancers treated with radiation: A surveillance, epidemiology, and end results analysis

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Shruthi Arora

2014-01-01

Conclusion: This is the first large population-based study evaluating PDTC and ATC outcomes in patients who received radiation treatment. Radioisotope use and timing of radiotherapy (postoperative vs. preoperative were associated with improved CSS in both histologies.

New comprehensive studies of a gold(III) Dithiocarbamate complex with proven anticancer properties: Aqueous dissolution with cyclodextrins, pharmacokinetics and upstream inhibition of the ubiquitin-proteasome pathway.

Science.gov (United States)

Tomasello, Marianna F; Nardon, Chiara; Lanza, Valeria; Di Natale, Giuseppe; Pettenuzzo, Nicolò; Salmaso, Stefano; Milardi, Danilo; Caliceti, Paolo; Pappalardo, Giuseppe; Fregona, Dolores

2017-09-29

The gold(III)-dithiocarbamate complex AuL12 (dibromo [ethyl-N-(dithiocarboxy-kS,kS')-N-methylglycinate] gold(III)), is endowed with promising in vitro/in vivo antitumor activity and toxicological profile. Here, we report our recent strategies to improve its water solubility and stability under physiological conditions along with our efforts for unravelling its tangled mechanism of action. We used three types of α-cyclodextrins (CDs), namely β-CD, Me-β-CD and HP-β-CD to prepare aqueous solutions of AuL12. The ability of these natural oligosaccharide carriers to enhance water solubility of hydrophobic compounds, allowed drug stability of AuL12 to be investigated. Moreover, pharmacokinetic experiments were first carried out for a gold(III) coordination compound, after i.v. injection of the nanoformulation AuL12/HP-β-CD to female mice. The gold content in the blood samples was detected at scheduled times by AAS (atomic absorption spectrometry) analysis, highlighting a fast biodistribution with a t β1/2 of few minutes and a slow escretion (t α1/2 of 14.3 h). The in vitro cytotoxic activity of AuL12 was compared with the AuL12/HP-β-CD mixture against a panel of three human tumor cell lines (i.e., HeLa, KB and MCF7). Concerning the mechanism of action, we previously reported the proteasome-inhibitory activity of some our gold(III)-based compounds. In this work, we moved from the proteasome target to upstream of the important ubiquitin-proteasome pathway, testing the effects of AuL12 on the polyubiquitination reactions involving the Ub-activating (E1) and -conjugating (E2) enzymes. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Multicomponent synthesis, biological evaluation and molecular docking of new spiro-oxindole derivatives

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M. Sapnakumari

2017-11-01

Full Text Available A new series of spiro-oxindoles that were identified based upon their ability to inhibit methionine tRNA synthase (PDB ID: 1PFV and glucosamine-6-phosphate synthase (PDB ID: 1JXA enzymes in virtual screening was synthesized by a three-component 1,3-dipolar cycloaddition method. The reaction proceeds through the formation of azomethine ylides generated in situ by the decarboxylative condensation of isatin and amino acids with dipolarophile chalcones. These compounds are active against Staphylococcus aureus, Escherichia coli, Aspergillus niger and Aspergillus flavus, supporting the in silico screening. In addition, their antitubercular activity was assessed using the MABA method. The compounds 3′-[(4-fluorophenylcarbonyl]-4′-phenylspiro[indole-3,2′-pyrrolidin]-2(1H-one 3a, 4′-(4-bromophenyl-3′-[(4-fluorophenylcarbonyl]-5′-(hydroxymethyl spiro[indole-3,2′-pyrrolidin]-2(1H-one 3e and 4′-(4-chlorophenyl-3′-[(4-fluorophenylcarbonyl]-5′-(2-methylpropylspiro[indole-3,2′-pyrrolidin]-2(1H-one 3g are potent molecules with MIC of 0.8 μg/mL. In the DPPH radical scavenging assay, compounds 4′-(4-chlorophenyl-3′-[(4-fluorophenylcarbonyl]spiro[indole-3,2′-pyrrolidin]-2(1H-one 3b, 4′-(4-chlorophenyl-3′-[(4-fluorophenylcarbonyl]-5′-(hydroxymethylspiro[indole-3,2′-pyrrolidin]-2(1H-one 3d and 4′-(4-bromophenyl-3′-[(4-fluorophenylcarbonyl]-5′-(hydroxymethylspiro[indole-3,2′-pyrrolidin]-2(1H-one 3e exhibited significant radical scavenging capacity. Keywords: Chalcone, Spiro-oxindole, Azomethine ylide, Antimicrobial activity, Molecular docking

Identification of solution products of lanthanoid (3) diethyldithiocarbamatohexamethyl phosphotriamide compounds from IR, electron and sup 1 H, sup 13 C, sup 31 P NMR absorption spectra. Identifikatsiya produktov rastvoreniya diehtilditiokarbamatogeksametil fosfotriamidnykh soedinenij lantanoidov (3) po IK, ehlektronnym i YaMR sup 1 H, sup 13 C, sup 31 P spektram pogloshcheniya

Energy Technology Data Exchange (ETDEWEB)

Skopenko, V V; Savost' yanova, A F; Trachevskij, V V; Gorbalyuk, A D; Sukhan, T A [Kievskij Gosudarstvennyj Univ., Kiev (Ukrainian SSR)

1991-01-01

By the methods of conductometry, IR, electron and {sup 1}H, {sup 13}C, {sup 31}P NMR spectroscopy nonaqueous solutions of the compounds (La(S{sub 2}CNEt{sub 2})Hmpa{sub 5})(BPh{sub 4}){sub 2}, Hmpa=OP(NMe{sub 2}){sub 3}; (Ln(S{sub 2}CNEt{sub 2}){sub 2}Hmpa{sub 3})BPh{sub 4}, Ln=Y, La-Lu; (Ln(S{sub 2}CNEt{sub 2}){sub 3}Hmpa{sub 2}), Ln=La-Gd, have been investigated. It is ascertained that bis-dithiocarbamate compounds are dissolved in all the studied solvents with preservation of composition and structure of lanthanide (3) inner coordination sphere. Tris-dithiocarbamates in nonaqueous solutions are subjected to reactions of ligand redistribution according to schemes depending on the solvent nature. In the process of dissolving of lanthanum monodithiocarbamate bond isomerization of dithiocarbamate groups occurs, which is pronounced in splitting of {sup 1}H and {sup 13}C NMR signals.

Angiotensin II induced inflammation in the kidney and in the heart of double transgenic rats

Directory of Open Access Journals (Sweden)

Haller Hermann

2002-01-01

Full Text Available Abstract Background We are investigating a double transgenic rat (dTGR model, in which rats transgenic for the human angiotensinogen and renin genes are crossed. These rats develop moderately severe hypertension but die of end-organ cardiac and renal damage by week 7. The heart shows necrosis and fibrosis, whereas the kidneys resemble the hemolytic-uremic syndrome vasculopathy. Surface adhesion molecules (ICAM-1 and VCAM-1 are expressed early on the endothelium, while the corresponding ligands are found on circulating leukocytes. Leukocyte infiltration in the vascular wall accompanies PAI-1, MCP-1, iNOS and Tissue Factor expression. Furthermore we show evidence that Ang II causes the upregulation of NF-kB in our model. Methods We started PDTC-treatment on four weeks old dTGR (200 mg/kg sc and age-matched SD rats.. Blood-pressure- and albuminuria- measurements were monitored during the treatement period (four weeks. The seven weeks old animals were killed, hearts and kidneys were isolated and used for immunohistochemical-and electromobility shift assay analsis. Results Chronic treatment with the antioxidant PDTC decreased blood pressure (162 ± 8 vs. 190 ± 7 mm Hg, p = 0.02. Cardiac hypertrophy index was significantly reduced (4.90 ± 0.1 vs. 5.77 ± 0.1 mg/g, p Conclusion Our data show that inhibition of NF-κB by PDTC markedly reduces inflammation, iNOS expression in the dTGR most likely leading to decreased cytotoxicity, and cell proliferation. Thus, NF-κB activation plays an important role in ANG II-induced end-organ damage.

(N-Benzyl-N-ethyl-dithio-carbamato)di-tert-butyl-chloridotin(IV).

Science.gov (United States)

Abdul Muthalib, Amirah Faizah; Baba, Ibrahim; Mohamed Tahir, Mohamed Ibrahim; Tiekink, Edward R T

2011-02-26

The Sn(IV) atom in the title diorganotin dithio-carbamate, [Sn(C(4)H(9))(2)Cl(C(10)H(12)NS(2))], is penta-coordinated by an asymmetrically coordinating dithio-carbamate ligand, a Cl and two C atoms of the Sn-bound tert-butyl groups. The resulting C(2)ClS(2) donor set defines a coordination geometry inter-mediate between square pyramidal and trigonal bipyramidal with a slight tendency towards the former. In the crystal structure, C-H⋯π contacts link centrosymmetrically related mol-ecules into dimeric aggregates.

Differential regulation of iron chelator-induced IL-8 synthesis via MAP kinase and NF-κB in immortalized and malignant oral keratinocytes

International Nuclear Information System (INIS)

Lee, Hwa-Jeong; Lee, Jun; Lee, Sun-Kyung; Lee, Suk-Keun; Kim, Eun-Cheol

2007-01-01

Interleukin-8 (IL-8) is a cytokine that plays an important role in tumor progression in a variety of cancer types; however, its regulation is not well understood in oral cancer cells. In the present study, we examined the expression and mechanism of IL-8 in which it is involved by treating immortalized (IHOK) and malignant human oral keratinocytes (HN12) cells with deferoxamine (DFO). IL-8 production was measured by an enzyme-linked immunoabsorbent assay and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. Electrophoretic mobility shift assays was used to determine NF-κB binding activity. Phosphorylation and degradation of the I-κB were analyized by Western blot. IHOK cells incubated with DFO showed increased expression of IL-8 mRNA, as well as higher release of the IL-8 protein. The up-regulation of DFO-induced IL-8 expression was higher in IHOK cells than in HN12 cells and was concentration-dependent. DFO acted additively with IL-1β to strongly up-regulate IL-8 in IHOK cells but not in HN12 cells. Accordingly, selective p38 and ERK1/2 inhibitors for both kinases abolished DFO-induced IL-8 expression in both IHOK and HN12 cells. Furthermore, DFO induced the degradation and phosphorylation of IκB, and activation of NF-κB. The IL-8 inducing effects of DFO were mediated by a nitric oxide donor (S-nitrosoglutathione), and by pyrrolidine dithiocarbamate, an inhibitor of NF-κB, as well as by wortmannin, which inhibits the phosphatidylinositol 3-kinase-dependent activation of NAD(P)H oxidase. This results demonstrate that DFO-induced IL-8 acts via multiple signaling pathways in immortalized and malignant oral keratinocytes, and that the control of IL-8 may be an important target for immunotheraphy against human oral premalignant lesions

Activation of the canonical nuclear factor-κB pathway is involved in isoflurane-induced hippocampal interleukin-1β elevation and the resultant cognitive deficits in aged rats

International Nuclear Information System (INIS)

Li, Zheng-Qian; Rong, Xiao-Ying; Liu, Ya-Jie; Ni, Cheng; Tian, Xiao-Sheng; Mo, Na; Chui, De-Hua; Guo, Xiang-Yang

2013-01-01

Highlights: •Isoflurane induces hippocampal IL-1β elevation and cognitive deficits in aged rats. •Isoflurane transiently activates the canonical NF-κB pathway in aged rat hippocampus. •NF-κB inhibitor mitigates isoflurane-induced IL-1β elevation and cognitive deficits. •We report a linkage between NF-κB signaling, IL-1β expression, and cognitive changes. -- Abstract: Although much recent evidence has demonstrated that neuroinflammation contributes to volatile anesthetic-induced cognitive deficits, there are few existing mechanistic explanations for this inflammatory process. This study was conducted to investigate the effects of the volatile anesthetic isoflurane on canonical nuclear factor (NF)-κB signaling, and to explore its association with hippocampal interleukin (IL)-1β levels and anesthetic-related cognitive changes in aged rats. After a 4-h exposure to 1.5% isoflurane in 20-month-old rats, increases in IκB kinase and IκB phosphorylation, as well as a reduction in the NF-κB inhibitory protein (IκBα), were observed in the hippocampi of isoflurane-exposed rats compared with control rats. These events were accompanied by an increase in NF-κB p65 nuclear translocation at 6 h after isoflurane exposure and hippocampal IL-1β elevation from 1 to 6 h after isoflurane exposure. Nevertheless, no significant neuroglia activation was observed. Pharmacological inhibition of NF-κB activation by pyrrolidine dithiocarbamate markedly suppressed the IL-1β increase and NF-κB signaling, and also mitigated the severity of cognitive deficits in the Morris water maze task. Overall, our results demonstrate that isoflurane-induced cognitive deficits may stem from upregulation of hippocampal IL-1β, partially via activation of the canonical NF-κB pathway, in aged rats

Dispersive liquid–liquid microextraction using diethyldithiocarbamate as a chelating agent and the dried-spot technique for the determination of Fe, Co, Ni, Cu, Zn, Se and Pb by energy-dispersive X-ray fluorescence spectrometry

International Nuclear Information System (INIS)

Kocot, Karina; Zawisza, Beata; Sitko, Rafal

2012-01-01

Dispersive liquid–liquid microextraction (DLLME) using sodium diethyldithiocarbamate (DDTC) as a chelating agent was investigated for the simultaneous determination of iron, cobalt, nickel, copper, zinc, selenium and lead ions in water samples. The procedure was performed using 5 mL of the sample, 100 μL of a 0.5% solution of DDTC, 30 μL of carbon tetrachloride (extraction phase) and 500 μL of methanol (disperser solvent). The experiments showed that Fe, Co, Ni, Cu, Zn and Pb can be simultaneously extracted at a pH of 5 and that Se can be extracted at a pH of 2–3. The results were compared with those obtained using ammonium pyrrolidine dithiocarbamate as a chelating agent. For all analytes, a linear range was observed up to 0.4 μg mL −1 . If Fe and Zn are present in concentrations 10 times higher than those of the other analytes, then the linearity is observed up to 0.2 μg mL −1 . In the present study, the organic phase that contained preconcentrated elements was deposited onto a Millipore filter and measured using energy-dispersive X-ray fluorescence spectrometry. The obtained detection limits were 2.9, 1.5, 2.0, 2.3, 2.5, 2.0 and 3.9 ng mL −1 for Fe, Co, Ni, Cu, Zn, Se and Pb, respectively. This combination of DLLME and the dried-spot technique is promising for multielement analyses using other spectroscopy techniques, such as laser ablation‐inductively coupled plasma‐mass spectrometry, laser-induced breakdown spectroscopy or total-reflection X-ray fluorescence spectrometry. - Highlights: ► Multielement trace analysis using dried-spot technique and dispersive liquid–liquid microextraction. ► Possibility of combination of LPME with EDXRF, LIBS or LA-ICP-MS. ► Comparison of APDC and DDTC as chelating agents.

Historically aggressive types of follicular cell-derived thyroid cancer often have radioactive avid distant metastases: a study of 314 patients with distant metastases at a single institution

Energy Technology Data Exchange (ETDEWEB)

Tala, H.P.; Rondeau, G.; Fagin, J.A.; Tuttle, R.M. [Endocrinology Division, Department of Medicine, Nuclear Medicine Division, Memorial Sloan Kettering Cancer Center, New-York (United States); Ghossein, R.A. [Pathology Department, Nuclear Medecine Division, Memorial Sloan Kettering Cancer Center, New-York (United States); Grewal, R.K.; Larson, S.M. [Radiology Department, Nuclear Medicine Division, Memorial Sloan Kettering Cancer Center, New-York (United States)

2012-07-01

Radioactive iodine (RAI) remains one of the primary treatment options for metastatic, follicular cell derived thyroid cancers. The aim of this study was to determine the likelihood that metastatic lesions arising from one of the aggressive thyroid cancer histologies [tall cell variant of papillary thyroid carcinoma (TCV-PTC), poorly differentiated thyroid carcinoma (PDTC) and Hurthle cell carcinoma (HCC)] would demonstrate sufficient RAI avidity for visualization on RAI scanning and therefore could potentially benefit from RAI therapy. The study shows that in patients selected for RAI scanning or therapy at our center, RAI avid lesions can be identified in more than two thirds of the patients with distant metastases arising in the setting of C-PTC, WD-FTC, FV-PTC, TCV-PTC, or PDTC primary tumors. While RAI avidity on a post-therapy scan does not always correlate with clinically significant tumor killing activity, it is likely that some of these patients with RAI avid metastatic disease did obtain a clinical benefit

In vitro Dissolution Studies on Solid Dispersions of Mefenamic Acid.

Science.gov (United States)

Rao, K R S Sambasiva; Nagabhushanam, M V; Chowdary, K P R

2011-03-01

Solid dispersions of mefanamic acid with a water-soluble polymer polyvinyl pyrrolidine and a super disintegrant, primojel were prepared by common solvent and solvent evaporation methods employing methanol as the solvent. The dissolution rate and dissolution efficiency of the prepared solid dispersions were evaluated in comparison to the corresponding pure drug. Solid dispersions of mefenamic acid showed a marked enhancement in dissolution rate and dissolution efficiency. At 1:4 ratio of mefenamic acid-primojel a 2.61 fold increase in the dissolution rate of mefenamic acid was observed with solid dispersion. The solid dispersions in combined carriers gave much higher rates of dissolution than super disintegrants alone. Mefanamic acid-primojel-polyvinyl pyrrolidine (1:3.2:0.8) solid dispersion gave a 4.11 fold increase in the dissolution rate of mefenamic acid. Super disintegrants alone or in combination with polyvinyl pyrrolidine could be used to enhance the dissolution rate of mefenamic acid.

Deoxyiminoalditols from Aldonic Acids - VI. - Preparation of the Four Stereoisomeric 4-Amino-3-hydroxypyrrolidines from Bromodeoxytetronic Acids. Discovery of a New alfa-Mannosidase Inhibitor

DEFF Research Database (Denmark)

Lundt, Inge; Limberg, Gerrit; Zavilla, John

1999-01-01

A convenient four step synthesis of amino hydroxy pyrrolidines is presented. From the readily available D- and L-tetronic acids the four possible stereoisomeric 4-amino-3-hydroxy pyrrolidines 14, 15, 17 and 19 could be accessed as crystalline compounds, avoiding any chromatographic purification....... The key step in the reactions was the regioselective formation of either the 2,4-diamino-2,4-dideoxy-D-threono-1,4-lactam (5) or the 3,4-diamino-3,4-dideoxy-L-erythrono-1,4-lactam (10) by treatment of the methyl 4-bromo-4-deoxy-2,3-cis- 3 or 2,3-trans- 9 epoxy tetronates, respectively, with liquid ammonia....... Thus, opposite regioselectivity for opening of the cis-configurated epoxide 3 (4 : 1, C-2 : C-3) and the trans-configurated epoxide 9 (3 : 7, C-2 : C-3) by ammonia was observed. - Initial testing as glycosidase inhibitors of the amino hydroxy pyrrolidines formed by reduction of the lactams showed...

Structural, functional, and evolutionary analysis of moeZ, a gene encoding an enzyme required for the synthesis of the Pseudomonas metabolite, pyridine-2,6-bis(thiocarboxylic acid

Directory of Open Access Journals (Sweden)

Crawford Ronald L

2002-04-01

Full Text Available Abstract Background Pyridine-2,6-bis(thiocarboxylic acid (pdtc is a small secreted metabolite that has a high affinity for transition metals, increases iron uptake efficiency by 20% in Pseudomonas stutzeri, has the ability to reduce both soluble and mineral forms of iron, and has antimicrobial activity towards several species of bacteria. Six GenBank sequences code for proteins similar in structure to MoeZ, a P. stutzeri protein necessary for the synthesis of pdtc. Results Analysis of sequences similar to P. stutzeri MoeZ revealed that it is a member of a superfamily consisting of related but structurally distinct proteins that are members of pathways involved in the transfer of sulfur-containing moieties to metabolites. Members of this family of enzymes are referred to here as MoeB, MoeBR, MoeZ, and MoeZdR. MoeB, the molybdopterin synthase activating enzyme in the molybdopterin cofactor biosynthesis pathway, is the most characterized protein from this family. Remarkably, lengths of greater than 73% nucleic acid homology ranging from 35 to 486 bp exist between Pseudomonas stutzeri moeZ and genomic sequences found in some Mycobacterium, Mesorhizobium, Pseudomonas, Streptomyces, and cyanobacteria species. Conclusions The phylogenetic relationship among moeZ sequences suggests that P. stutzeri may have acquired moeZ through lateral gene transfer from a donor more closely related to mycobacteria and cyanobacteria than to proteobacteria. The importance of this relationship lies in the fact that pdtc, the product of the P. stutzeri pathway that includes moeZ, has an impressive set of capabilities, some of which could make it a potent pathogenicity factor.

Muscular contractions in the zebrafish embryo are necessary to reveal thiuram-induced notochord distortions

International Nuclear Information System (INIS)

Teraoka, Hiroki; Urakawa, Satsuki; Nanba, Satomi; Nagai, Yuhki; Wu Dong; Imagawa, Tomohiro; Tanguay, Robert L.; Svoboda, Kurt; Handley-Goldstone, Heather M.; Stegeman, John J.; Hiraga, Takeo

2006-01-01

Dithiocarbamates form a large group of chemicals that have numerous uses in agriculture and medicine. It has been reported that dithiocarbamates, including thiuram (tetramethylthiuram disulfide), cause wavy distortions of the notochord in zebrafish and other fish embryos. In the present study, we investigated the mechanism underlying the toxicity of thiuram in zebrafish embryos. When embryos were exposed to thiuram (2-1000 nM: 0.48-240 μg/L) from 3 h post fertilization (hpf) (30% epiboly) until 24 hpf (Prim-5), all embryos develop wavy notochords, disorganized somites, and have shortened yolk sac extensions. The thiuram response was specific and did not cause growth retardation or mortality at 24 hpf. The thiuram-dependent responses showed the same concentration dependence with a waterborne EC 5 values of approximately 7 nM. Morphometric measurements revealed that thiuram does not affect the rate of notochord lengthening. However, the rate of overall body lengthening was significantly reduced in thiuram-exposed animals. Other dithiocarbamates, such as ziram, caused similar malformations to thiuram. While expression of genes involved in somitogenesis was not affected, the levels of notochord-specific transcripts were altered after the onset of malformations. Distortion of the notochord started precisely at 18 hpf, which is concomitant with onset of spontaneous rhythmic trunk contractions. Abolishment of spontaneous contractions using tricaine, α-bungarotoxin, and a paralytic mutant sofa potato, resulted in normal notochord morphology in the presence of thiuram. These results indicate that muscle activity is necessary to reveal the underlying functional deficit and suggest that the developmental target of dithiocarbamates impairs trunk plasticity through an unknown mechanism

Structural and sensory characterization of key pungent and tingling compounds from black pepper (Piper nigrum L.).

Science.gov (United States)

Dawid, Corinna; Henze, Andrea; Frank, Oliver; Glabasnia, Anneke; Rupp, Mathias; Büning, Kirsten; Orlikowski, Diana; Bader, Matthias; Hofmann, Thomas

2012-03-21

To gain a more comprehensive knowledge on whether, besides the well-known piperine, other compounds are responsible for the pungent and tingling oral impression imparted by black pepper, an ethanol extract prepared from black pepper (Piper nigrum L.) was screened for its key sensory-active nonvolatiles by application of taste dilution analysis (TDA). Purification of the compounds perceived with the highest sensory impact, followed by LC-MS and 1D/2D NMR experiments as well as synthesis, led to the structure determination of 25 key pungent and tingling phytochemicals, among which the eight amides 1-(octadeca-2E,4E,13Z-trienyl)piperidine, 1-(octadeca-2E,4E,13Z-trienyl)pyrrolidine, (2E,4E,13Z)-N-isobutyl-octadeca-2,4,13-trienamide, 1-(octadeca-2E,4E,12Z-trienoyl)-pyrrolidine, 1-(eicosa-2E,4E,15Z-trienyl)piperidine, 1-(eicosa-2E,4E,15Z-trienyl)pyrrolidine, (2E,4E,15Z)-N-isobutyl-eicosa-2,4,15-trienamide, and 1-(eicosa-2E,4E,14Z-trienoyl)-pyrrolidine were not yet reported in literature. Sensory studies by means of a modified half-tongue test revealed recognition thresholds ranging from 3.0 to 1150.2 nmol/cm² for pungency and from 520.6 to 2162.1 nmol/cm² for the tingling orosensation depending on their chemical structure.

Synthesis and properties of radiation stabilized poly(α-amino acid)

International Nuclear Information System (INIS)

Nakagawa, T.; Shibata, T.

1981-01-01

In previous papers, one of the authors reported that modified poly(vinyl chloride) containing dithiocarbamate group has an excellent antiradiation property against γ-irradiation from the viewpoint of a negligibly small gaseous product, especially hydrogen chloride which was generated by radiolysis. Our studies of antiradiation polymers have now been extended to examine the stability of modified poly(α-amino acid) against γ-irradiation. Poly(α-amino acid) membranes have already been shown to be biologically compatible with blood and tissue. However, for practical uses of synthetic biomaterials, they would be required to be stable in the sterilization processing. The sterilization by γ-irradiation is more profitable for poly(α-amino acid) membranes which are less thermally stable. On the other hand, the transport of oxygen through poly(α-amino acid) membranes is of special interest because of the importance as a biomaterial for artificial lungs, skin and corneas. The purpose of the present study is to synthesize the antiradiation poly(α-amino acid) membranes by dithiocarbamate substitution, as well as to study the effect of dithiocarbamate substitution on the transport property of gases. (author)

Case series

African Journals Online (AJOL)

ebutamanya

2015-06-22

Jun 22, 2015 ... entity, few data are available on its features and none of them involves patients in North Africa. To date, there is no explicit consensus to sets PDTC patients' management. This study intended to report the experience of a tertiary medical centre in Morocco by reporting patients' features, clinical stage at the ...

Ethyl 27-oxo-15-oxa-2,20-diazahexacyclo[18.6.1.01,8.02,6.09,14.021,26]heptacosa-9,11,13,21,23,25-hexaene-7-carboxylate

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Devadasan Velmurugan

2013-01-01

Full Text Available In the title compound, C27H30N2O4, the pyrrolidine ring adopts a twisted conformation. The indoline ring system is almost perpendicular to the mean plane of the pyrrolidine ring, making a dihedral angle of 81.7 (8°. In the crystal, molecules are linked into centrosymmetric dimers with graph-set motif R22(16 via pairs of C—H...O hydrogen bonds. The terminal ethyl group of the ester group is disordered over two sets of sites, with a site-occupancy ratio of 0.587 (11:0.413 (11.

(N-Benzyl-N-isopropyldithiocarbamatochloridodiphenyltin(IV

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Amirah Faizah Abdul Muthalib

2010-09-01

Full Text Available The SnIV atom in the title organotin dithiocarbamate, [Sn(C6H52(C11H14NS2Cl], is penta-coordinated by an asymmetrically coordinating dithiocarbamate ligand, a Cl and two ispo-C atoms of the Sn-bound phenyl groups. The resulting C2ClS2 donor set defines a coordination geometry intermediate between square-pyramidal and trigonal-bipyramidal with a slight tendency towards the latter. The formation of close intramolecular C–H...Cl and C–H...S contacts precludes the Cl and S atoms from forming significant intermolecular contacts. The presence of C–H...π contacts leads to the formation of supramolecular arrays that stack along the b axis.

Remedial action of matrices contaminated by cobalt with supercritical CO_2: contribution to the understanding of the complex formation mechanisms and to the diphasic transfers

International Nuclear Information System (INIS)

Gervais, Florence

2001-01-01

Soils rehabilitation using supercritical CO_2 seems an interesting alternative way to existing techniques. No effluents are generated during the supercritical fluid extraction, which is the main advantage of this process. In order to be extracted by this techniques, metals or radionuclides have to be complexed by suitable chelating agents. Beta-diketones and dithiocarbamates (fluorinated or not) have been chosen. The first part of this work deals with chemical equilibria mechanisms study in an aqueous phase. Experiments show a very weak cobalt complexation kinetics with acetylacetone. Moreover, this complex exhibit a hydrophilic behaviour. On the other hand, cobalt and dithiocarbamate instantaneously from a chelate which is very hydrophobic. Mass transfer between extracting and aqueous phases (hexane and SC CO_2) are also investigated. Supercritical CO_2 seems to have a greater affinity towards fluorinated beta-diketones than hexane. This tendency is confirmed by in situ commercial chelates (fluorinates or not) solubility measurements using X-ray absorption spectroscopy. However, cobalt-beta-diketonates are hydrophilic because of their partial hydration. This kind of chelating agents is not suitable to cobalt supercritical fluid extraction from an aqueous phase. Inversely, distribution coefficients of hydrophobic dithiocarbamates are higher than beta-diketonates, whatever the extracting solvent is. Metals extraction from an aqueous matrix seems possible with these chelating agents. (author) [fr

(1′S-4-(3,4-Dichlorophenyl-1′-(3,5-dimethoxyphenyl-1,2,3,4-tetrahydronaphthalene-2-spiro-2′-pyrrolizidine-3′-spiro-3′′-indoline-1,2′′-dione

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S. Sriman Narayanan

2008-10-01

Full Text Available In the title compound C37H32Cl2N2O4, the unsubstituted pyrrolidine ring shows a twist conformation whereas the substituted pyrrolidine ring shows an envelope conformation. The dimethoxy benzene ring is perpendicular to the tetralone ring, making a dihedral angle of 89.94 (5°. Molecules are linked into centrosymmetric dimers by N—H...O hydrogen bonds and the crystal structure is stabilized by C—H...π interactions and C—H...O hydrogen bonds. One methoxy group is disordered over two positions with the site occupancy factors of 0.84 (2 and 0.16 (2.

The truncate mutation of Notch2 enhances cell proliferation through activating the NF-κB signal pathway in the diffuse large B-cell lymphomas.

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Xinxia Zhang

Full Text Available The Notch2 is a critical membrane receptor for B-cell functions, and also displays various biological roles in lymphoma pathogenesis. In this article, we reported that 3 of 69 (4.3% diffuse large B-cell lymphomas (DLBCLs exhibited a truncate NOTCH2 mutation at the nucleotide 7605 (G/A in the cDNA sequence, which led to partial deletion of the C-terminal of PEST (proline-, glutamic acid-, serine- and threonine-rich domain. The truncate Notch2 activated both the Notch2 and the NF-κB signals and promoted the proliferation of B-cell lymphoma cell lines, including DLBCL and Burkitt's lymphoma cell lines. Moreover, the ectopic proliferation was completely inhibited by ammonium pyrrolidinedithiocarbamate (PDTC, an NF-κB inhibitor. Simultaneously, PDTC also reduced the expression level of Notch2. Based on these results, we conclude that the Notch2 receptor with PEST domain truncation enhances cell proliferation which may be associated with the activation of the Notch2 and the NF-κB signaling. Our results are expected to provide a possible target for new DLBCL therapies by suppressing the Notch2 and the NF-κB signaling.

(N-Benzyl-N-isopropyl-dithio-carbamato)chloridodiphenyl-tin(IV).

Science.gov (United States)

Abdul Muthalib, Amirah Faizah; Baba, Ibrahim; Mohamed Tahir, Mohamed Ibrahim; Ng, Seik Weng; Tiekink, Edward R T

2010-08-11

The Sn(IV) atom in the title organotin dithio-carbamate, [Sn(C(6)H(5))(2)(C(11)H(14)NS(2))Cl], is penta-coordinated by an asymmetrically coordinating dithio-carbamate ligand, a Cl and two ispo-C atoms of the Sn-bound phenyl groups. The resulting C(2)ClS(2) donor set defines a coordination geometry inter-mediate between square-pyramidal and trigonal-bipyramidal with a slight tendency towards the latter. The formation of close intra-molecular C-H⋯Cl and C-H⋯S contacts precludes the Cl and S atoms from forming significant inter-molecular contacts. The presence of C-H⋯π contacts leads to the formation of supra-molecular arrays that stack along the b axis.

Sequential cloud point extraction for the speciation of mercury in seafood by inductively coupled plasma optical emission spectrometry

Energy Technology Data Exchange (ETDEWEB)

Li Yingjie [Department of Chemistry, Wuhan University, Wuhan 430072 (China); Hu Bin [Department of Chemistry, Wuhan University, Wuhan 430072 (China)], E-mail: binhu@whu.edu.cn

2007-10-15

A novel nonchromatographic speciation technique for the speciation of mercury by sequential cloud point extraction (CPE) combined with inductively coupled plasma optical emission spectrometry (ICP-OES) was developed. The method based on Hg{sup 2+} was complexed with I{sup -} to form HgI{sub 4}{sup 2-}, and the HgI{sub 4}{sup 2-} reacted with the methyl green (MG) cation to form hydrophobic ion-associated complex, and the ion-associated complex was then extracted into the surfactant-rich phase of the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114), which are subsequently separated from methylmercury (MeHg{sup +}) in the initial solution by centrifugation. The surfactant-rich phase containing Hg(II) was diluted with 0.5 mol L{sup -1} HNO{sub 3} for ICP-OES determination. The supernatant is also subjected to the similar CPE procedure for the preconcentration of MeHg{sup +} by the addition of a chelating agent, ammonium pyrrolidine dithiocarbamate (APDC), in order to form water-insolvable complex with MeHg{sup +}. The MeHg{sup +} in the micelles was directly analyzed after disposal as describe above. Under the optimized conditions, the extraction efficiency was 93.5% for Hg(II) and 51.5% for MeHg{sup +} with the enrichment factor of 18.7 for Hg(II) and 10.3 for MeHg{sup +}, respectively. The limits of detection (LODs) were 56.3 ng L{sup -1} for Hg(II) and 94.6 ng L{sup -1} for MeHg{sup +} (as Hg) with the relative standard deviations (RSDs) of 3.6% for Hg(II) and 4.5% for MeHg{sup +} (C = 10 {mu}g L{sup -1}, n = 7), respectively. The developed technique was applied to the speciation of mercury in real seafood samples and the recoveries for spiked samples were found to be in the range of 93.2-108.7%. For validation, a certified reference material of DORM-2 (dogfish muscle) was analyzed and the determined values are in good agreement with the certified values.

Determinação de cobre, ferro, manganês e zinco, num mesmo extrato de planta, por potometria de chama de absorção The determination of copper, iron, manganese and zinc in a bulk plant extract by atomic absorption spectrophotometry

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J. Romano Gallo

1971-05-01

Full Text Available É apresentado um método de determinação, num mesmo extrato de planta, de ferro, manganês e zinco na fase aquosa, e de cobre, após sua extração em solvente orgânico. Para êsse estudo usou-se um analisador automático de absorção atômica Perkin-Elmer, modêlo 4A. Somente á silica, em certas concentrações, poderá constituir problema na determinação de manganês ou ferro, na ausência de cálcio. Na extração quantitativa do cobre é necessário conservar o pH abaixo de 2, para evitar interferência de ferro.A method was developed to determine quantitatively Cu, Fe, Mn and Zn in a bulk plant extract, using flame absorption photometry. The process measures Fe, Mn and Zn directly in the aqueous solution, but a concentration of the extract with organic solvents is required for copper determination. Essentially the process consists in obtaining the plant extract through digestion of 1.000 g of the ground dry samples, with HNO3 and later with HC10(4-H2S0(4 (7:1 v/v, then the solution is diluted to 50 ml with water. Thirty ml of this solution are transferred to a separatory funnel, where the copper is extracted by the ammonium pyrrolidine dithiocarbamate/ methyl isobutyl ketone system, and its amount determined. It is necessary to keep the pH below 2 to avoid interference of Fe on Cu determination. Mn, Fe and Zn are determined directly in the remaining 20 ml of plant extract. It has been noticed that silicon might cause some problems in the determination of Fe and Mn, in the absence of Ca. All the determinations were made in a Perkin-Elmer mod. 4A atomic absorption automatic analyser.

Sequential cloud point extraction for the speciation of mercury in seafood by inductively coupled plasma optical emission spectrometry

International Nuclear Information System (INIS)

Li Yingjie; Hu Bin

2007-01-01

A novel nonchromatographic speciation technique for the speciation of mercury by sequential cloud point extraction (CPE) combined with inductively coupled plasma optical emission spectrometry (ICP-OES) was developed. The method based on Hg 2+ was complexed with I - to form HgI 4 2- , and the HgI 4 2- reacted with the methyl green (MG) cation to form hydrophobic ion-associated complex, and the ion-associated complex was then extracted into the surfactant-rich phase of the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114), which are subsequently separated from methylmercury (MeHg + ) in the initial solution by centrifugation. The surfactant-rich phase containing Hg(II) was diluted with 0.5 mol L -1 HNO 3 for ICP-OES determination. The supernatant is also subjected to the similar CPE procedure for the preconcentration of MeHg + by the addition of a chelating agent, ammonium pyrrolidine dithiocarbamate (APDC), in order to form water-insolvable complex with MeHg + . The MeHg + in the micelles was directly analyzed after disposal as describe above. Under the optimized conditions, the extraction efficiency was 93.5% for Hg(II) and 51.5% for MeHg + with the enrichment factor of 18.7 for Hg(II) and 10.3 for MeHg + , respectively. The limits of detection (LODs) were 56.3 ng L -1 for Hg(II) and 94.6 ng L -1 for MeHg + (as Hg) with the relative standard deviations (RSDs) of 3.6% for Hg(II) and 4.5% for MeHg + (C = 10 μg L -1 , n = 7), respectively. The developed technique was applied to the speciation of mercury in real seafood samples and the recoveries for spiked samples were found to be in the range of 93.2-108.7%. For validation, a certified reference material of DORM-2 (dogfish muscle) was analyzed and the determined values are in good agreement with the certified values

Aspirin suppresses the abnormal lipid metabolism in liver cancer cells via disrupting an NFκB-ACSL1 signaling

International Nuclear Information System (INIS)

Yang, Guang; Wang, Yuan; Feng, Jinyan; Liu, Yunxia; Wang, Tianjiao; Zhao, Man; Ye, Lihong; Zhang, Xiaodong

2017-01-01

Abnormal lipid metabolism is a hallmark of tumorigenesis. Hence, the alterations of metabolism enhance the development of hepatocellular carcinoma (HCC). Aspirin is able to inhibit the growth of cancers through targeting nuclear factor κB (NF-κB). However, the role of aspirin in disrupting abnormal lipid metabolism in HCC remains poorly understood. In this study, we report that aspirin can suppress the abnormal lipid metabolism of HCC cells through inhibiting acyl-CoA synthetase long-chain family member 1 (ACSL1), a lipid metabolism-related enzyme. Interestingly, oil red O staining showed that aspirin suppressed lipogenesis in HepG2 cells and Huh7 cells in a dose-dependent manner. In addition, aspirin attenuated the levels of triglyceride and cholesterol in the cells, respectively. Strikingly, we identified that aspirin was able to down-regulate ACSL1 at the levels of mRNA and protein. Moreover, we validated that aspirin decreased the nuclear levels of NF-κB in HepG2 cells. Mechanically, PDTC, an inhibitor of NF-κB, could down-regulate ACSL1 at the levels of mRNA and protein in the cells. Functionally, PDTC reduced the levels of lipid droplets, triglyceride and cholesterol in HepG2 cells. Thus, we conclude that aspirin suppresses the abnormal lipid metabolism in HCC cells via disrupting an NFκB-ACSL1 signaling. Our finding provides new insights into the mechanism by which aspirin inhibits abnormal lipid metabolism of HCC. Therapeutically, aspirin is potentially available for HCC through controlling abnormal lipid metabolism. - Highlights: • Aspirin inhibits the levels of liquid droplets, triglyceride and cholesterol in HCC cells. • Aspirin is able to down-regulate ACSL1 in HCC cells. • NF-κB inhibitor PDTC can down-regulate ACSL1 and reduces lipogenesis in HCC cells. • Aspirin suppresses the abnormal lipid metabolism in HCC cells via disrupting an NFκB-ACSL1 signaling.

Current Status on Biochemistry and Molecular Biology of Microbial Degradation of Nicotine

Science.gov (United States)

Gurusamy, Raman; Natarajan, Sakthivel

2013-01-01

Bioremediation is one of the most promising methods to clean up polluted environments using highly efficient potent microbes. Microbes with specific enzymes and biochemical pathways are capable of degrading the tobacco alkaloids including highly toxic heterocyclic compound, nicotine. After the metabolic conversion, these nicotinophilic microbes use nicotine as the sole carbon, nitrogen, and energy source for their growth. Various nicotine degradation pathways such as demethylation pathway in fungi, pyridine pathway in Gram-positive bacteria, pyrrolidine pathway, and variant of pyridine and pyrrolidine pathways in Gram-negative bacteria have been reported. In this review, we discussed the nicotine-degrading pathways of microbes and their enzymes and biotechnological applications of nicotine intermediate metabolites. PMID:24470788

Studies on the Red Sea Sponge Haliclona sp. for its Chemical and Cytotoxic Properties.

Science.gov (United States)

Al-Massarani, Shaza Mohamed; El-Gamal, Ali Ali; Al-Said, Mansour Sulaiman; Abdel-Kader, Maged S; Ashour, Abdelkader E; Kumar, Ashok; Abdel-Mageed, Wael M; Al-Rehaily, Adnan Jathlan; Ghabbour, Hazem A; Fun, Hoong-Kun

2016-01-01

A great number of novel compounds with rich chemical diversity and significant bioactivity have been reported from Red Sea sponges. To isolate, identify, and evaluate the cytotoxic activity of the chemical constituents of a sponge belonging to genus Haliclona collected from the Eastern coast of the Red Sea. The total ethanolic extract of the titled sponge was subjected to intensive chromatographic fractionation and purification guided by cytotoxic bioassay toward various cancer cell lines. The structures of the isolated compounds were elucidated using spectroscopic techniques including one-dimension and two-dimension nuclear magnetic resonance, mass spectrometry, ultraviolet, and infrared data, as well as comparison with the reported spectral data for the known compounds. X-ray single-crystal structure determination was performed to determine the absolute configuration of compound 4. The screening of antiproliferative activity of the compounds was carried on three tumor cell lines, namely the human cervical cancer (HeLa), human hepatocellular carcinoma (HepG2), and human medulloblastoma (Daoy) cells using MTT assay. This investigation resulted in the isolation of a new indole alkaloid, 1-(1H-indol-3-yloxy) propan-2-ol (1), with the previously synthesized pyrrolidine alkaloid, (2R, 3S, 4R, 5R) pyrrolidine-(1-hydroxyethyl)-3,4-diol hydrochloride (4), isolated here from a natural source for the first time. In addition, six known compounds tetillapyrone (2), nortetillapyrone (3), 2-methyl maleimide-5-oxime (5), maleimide-5-oxime (6), 5-(hydroxymethyl) dihydrofuran-2 (3H)-one (7), and ergosta-5,24 (28)-dien-3-ol (8) were also identified. Most of the isolated compounds exhibited weak cytotoxic activity against HepG-2, Daoy, and HeLa cancer cell lines. This is the first report of the occurrence of the indole and pyrrolidine alkaloids, 1-(1H-indol-2-yloxy) propan-2-ol (1), and the - (1-hydroxyethyl)-3,4-diol hydrochloride (4), in the Red Sea Haliclona sp. From the Red Sea

11-[(E-Benzylidene]-14-hydroxy-8-phenyl-6-thia-3,13-diazaheptacyclo[13.7.1.19,13.02,9.02,14.03,7.019,23]tetracosa-1(22,15(23,16,18,20-pentaen-10-one

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Raju Suresh Kumar

2012-07-01

Full Text Available In the title compound, C34H28N2O2S, the piperidine ring adopts a chair conformation. One of the pyrrolidine rings adopts an envelope conformation with the methylene C atom at the flap whereas the other pyrrolidine ring and the thiazolidine ring adopt half-chair conformations. The mean plane of the dihydroacenaphthylene ring system [maximum deviation = 0.067 (1 Å] makes dihedral angles of 28.31 (5 and 31.32 (6° with the two terminal benzene rings. An intramolecular O—H...N hydrogen bond forms an S(5 ring motif. In the crystal, molecules are linked by C—H...O and C—H...S hydrogen bonds into layers lying parallel to the ac plane.

Synthesis of cefepime-d3 and cefepime-d8

International Nuclear Information System (INIS)

Kamachi, Hajime; Okita, Takaaki; Tsuno, Takashi; Naito, Takayuki

1990-01-01

Synthesis of cefepime-d 3 (6a) and cefepime-d 8 (6b) is described. Diphenylmethyl 7-benzylideneamino-3-chloromethyl-3-cephem-4-carboxylate (2) was treated with sodium iodide to afford the iodide 3, which was without isolation, allowed to react with N-methyl-d 3 -pyrrolidine to give the quaternary salt 4a. Deblocking of 4a with HCO 2 H and HCl gave 7-amino-3-(N-methyl-d3-pyrrolidinio)methyl-3-cephem-4-carboxylate hydrochloride (5a). Acylation of 5a with benzotriazol-1-yl (Z)-2-(2-aminothiazol-4-yl)-2-methoxyiminoacetate followed by treatment with dil. H 2 SO 4 afforded 6a sulfate. In the same way, 6b was synthesized using N-methyl-pyrrolidine-d 8 . (author)

Ring Expansion of Vinylaziridines through the Strain-Release Pericyclic Reaction: Recent Developments and Applications

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Yu Mi Heo

2013-08-01

Full Text Available Recent syntheses of azetidines, pyrrolidines, piperidines and azepines through cycloaddition or sigmatropic rearrangements of vinylaziridines are described. Applications to natural product synthesis and mechanistic investigations are also summarized.

Synthesis of anisotropic CdS nanostructures via a single-source route

CSIR Research Space (South Africa)

Rajasekhar Pullabhotla, VSR

2011-02-01

Full Text Available A cadmium tetrahydroisoquinoline dithiocarbamate (DTC) complex has been used as single-source precursor for the synthesis of highly faceted hexadecylamine (HDA) capped CdS nanoparticles. Hexagonal and close to cubic shaped particles with distinct...

Bis(N,N-diethyldithiocarbamato-κ2S,S′(3-hydroxypyridine-κNzinc and bis[N-(2-hydroxyethyl-N-methyldithiocarbamato-κ2S,S′](3-hydroxypyridine-κNzinc: crystal structures and Hirshfeld surface analysis

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Mukesh M. Jotani

2016-12-01

Full Text Available The common feature of the molecular structures of the title compounds, [Zn(C5H10NS22(C5H5NO], (I, and [Zn(C4H8NOS22(C5H5NO], (II, are NS4 donor sets derived from N-bound hydroxypyridyl ligands and asymmetrically chelating dithiocarbamate ligands. The resulting coordination geometries are highly distorted, being intermediate between square pyramidal and trigonal bipyramidal for both independent molecules comprising the asymmetric unit of (I, and significantly closer towards square pyramidal in (II. The key feature of the molecular packing in (I is the formation of centrosymmetric, dimeric aggregates sustained by pairs of hydroxy-O—H...S(dithiocarbamate hydrogen bonds. The aggregates are connected into a three-dimensional architecture by methylene-C—H...O(hydroxy and methyl-C—H...π(chelate interactions. With greater hydrogen-bonding potential, supramolecular chains along the c axis are formed in the crystal of (II, sustained by hydroxy-O—H...O(hydroxy hydrogen bonds, with ethylhydroxy and pyridylhydroxy groups as the donors, along with ethylhydroxy-O—H...S(dithiocarbamate hydrogen bonds. Chains are connected into layers in the ac plane by methylene-C—H...π(chelate interactions and these stack along the b axis, with no directional interactions between them. An analysis of the Hirshfeld surfaces clearly distinguished the independent molecules of (I and reveals the importance of the C—H...π(chelate interactions in the packing of both (I and (II.

Life threatening central nervous system manifestations and hypothermia due to maneb intoxication in a child : a case report

NARCIS (Netherlands)

de Tollenaer, S M; Buysse, Cmp; van den Anker, J N; Touw, D J; de Hoog, M

2006-01-01

Maneb, manganese ethylene-bis-dithiocarbamate, is a fungicide pesticide used in the agriculture and bulb flower culture sector. Toxicological effects for humans have been reported in literature and are diverse. They vary from allergic reactions (dermatitis, conjunctivitis, and bronchitis), central

21 CFR 181.30 - Substances used in the manufacture of paper and paperboard products used in food packaging.

Science.gov (United States)

2010-04-01

... cyanodithioimidocarbamate with ethylene diamine and potassium N-methyl dithiocarbamate and/or sodium 2-mercaptobenzothiazole (slimicides).* Ethyl acrylate and methyl methacrylate copolymers of itaconic acid or methacrylic acid for use... acid (polymerized). Melamine formaldehyde polymer. Methyl acrylate (polymerized). Methyl ethers of mono...

Effect of thiram on chicken growth plate cartilage

Science.gov (United States)

Thiram is a general use dithiocarbamate pesticide. It causes tibial dyschondroplasia, a growth plate cartilage defect in poultry characterized by growth plate broadening due to the accumulation of nonviable chondrocytes which lead to lameness. Since proteins play significant roles in all aspects cel...

Synthesis and in vitro Evaluation of New Benzothiazole Derivatives as Schistosomicidal Agents

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Mona A Mahran

2007-03-01

Full Text Available A series of benzothiazol-2-yl-dithiocarbamates 3a-d along with their copper complexes 4a-c were synthesized via the reaction of suitable alkyl, aralkyl or heteroaryl halides with the sodium salt of benzothiazol-2-yl-dithiocarbamic acid, followed by complexation with copper sulphate. N-(4-Acetyl-5-aryl-4,5-dihydro-1,3,4-thiadiazol-2-yl-N-benzothiazol-2-yl-acetamides 7a-c were synthesized by cyclization of the appropriate thiosemicarbazones 6a-c in acetic anhydride. Selected compounds were screened for in vitro schistosomicidal activity against Schistosoma mansoni at three different dosage levels (10, 50 and 100 μg/ mL. Three of these products, 4a-c, showed schistosomicidal activity similar to praziquantel, with 100% worm mortality at 10 μg/mL. These compounds would constitute a new class of potent schistosomicidal agents.

Effects of the fungicide metiram in outdoor freshwater microcosms: responses of invertebrates, primany producers and microbes

NARCIS (Netherlands)

Ronghua, Lin; Buijse-Bogdan, L.L.; Rocha Dimitrov, M.; Dohmen, P.; Kosol, Sujitra; Maltby, L.; Roessink, I.; Sinkeldam, J.A.; Smidt, H.; Wijngaarden, van R.P.A.; Brock, T.C.M.

2012-01-01

The ecological impact of the dithiocarbamate fungicide metiram was studied in outdoor freshwater microcosms, consisting of 14 enclosures placed in an experimental ditch. The microcosms were treated three times (interval 7 days) with the formulated product BAS 222 28F (Polyram®). Intended metiram

Bis(N-ethyl-N-methyldithiocarbamato-κ2S,S′diphenyltin(IV

Directory of Open Access Journals (Sweden)

Amirah Faizah Muthalib

2010-04-01

Full Text Available The dithiocarbamate anions in the title compound, [Sn(C6H52(C4H8NS22], chelate to the SnIV atom, which is six-coordinated in a skew-trapezoidal-bipyramidal geometry. The molecule lies across a twofold rotation axis.

Bis(N-isopropyl-N-methyldithiocarbamato-κ2S,S′diphenyltin(IV

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Amirah Faizah Muthalib

2010-04-01

Full Text Available The dithiocarbamate anions in the title compound, [Sn(C6H52(C5H10NS22], chelate to the SnIV atom, which is six-coordinated in a skew-trapezoidal-bipyramidal geometry. The molecule lies across a twofold rotation axis.

4′-Methyl-14′,19′-dioxa-4′-azaspiro[acenaphthylene-1,5′-tetracyclo[18.4.0.02,6.08,13]tetracosane]-1′(24′,8′,10′,12′,20′,22′-hexaene-2,7′(1H-dione

Directory of Open Access Journals (Sweden)

Sibi Narayanan

2012-12-01

Full Text Available In the title compound, C33H29NO4, the acenaphthylene ring system is essentially planar (r.m.s. deviation = 0.0290 Å. The pyrrolidine ring adopts a C-envelope conformation with a C atom displaced by 0.671 (2 Å from the mean-plane formed by the remaining ring atoms. The pyrrolidine ring is fused to acenaphthylene ring system making a dihedral angle of 88.0 (7°. In the crystal, molecules are linked into R22(9 dimers via C—H...N and C—H...O hydrogen bonds. Two C atoms act as donors to the same O atom acceptor, resulting in the formation of R21(7 ring motifs. These two motifs combine to form hydrogen-bonded sheets running along the a- and b-axis directions.

Human Acid β-Glucosidase Inhibition by Carbohydrate Derived Iminosugars: Towards New Pharmacological Chaperones for Gaucher Disease.

Science.gov (United States)

Parmeggiani, Camilla; Catarzi, Serena; Matassini, Camilla; D'Adamio, Giampiero; Morrone, Amelia; Goti, Andrea; Paoli, Paolo; Cardona, Francesca

2015-09-21

A collection of carbohydrate-derived iminosugars belonging to three structurally diversified sub-classes (polyhydroxylated pyrrolidines, piperidines, and pyrrolizidines) was evaluated for inhibition of human acid β-glucosidase (glucocerebrosidase, GCase), the deficient enzyme in Gaucher disease. The synthesis of several new pyrrolidine analogues substituted at the nitrogen or α-carbon atom with alkyl chains of different lengths suggested an interpretation of the inhibition data and led to the discovery of two new GCase inhibitors at sub-micromolar concentration. In the piperidine iminosugar series, two N-alkylated derivatives were found to rescue the residual GCase activity in N370S/RecNcil mutated human fibroblasts (among which one up to 1.5-fold). This study provides the starting point for the identification of new compounds in the treatment of Gaucher disease. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Crystal structure of 2′-[(2′,4′-difluorobiphenyl-4-ylcarbonyl]-1′-phenyl-1′,2′,5′,6′,7′,7a'-hexahydrospiro[indole-3,3′-pyrrolizin]-2(1H-one

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M. Fathimunnisa

2015-08-01

Full Text Available In the title pyrrolizidine derivative, C33H26F2N2O2, both pyrrolidine rings of the pyrrolizidine moiety adopt an envelope conformation. The difluorophenyl group is oriented at an angle of 54.3 (1° with respect to the oxindole moiety. The crystal packing features an N—H...O hydrogen bond, which forms an R22(8 motif, and a C—H...O interaction, which generates a C(8 chain along [010]. In addition, this chain structure is stabilized by C—H...π interactions. In one of the pyrrolidine rings, the methylene group forming the flap of an envelope and the H atoms of the adjacent methylene groups are disordered over two sets of sites, with site-occupancy factors of 0.571 (4 and 0.429 (4

An Ugi Reaction Incorporating a Redox-Neutral Amine C-H Functionalization Step.

Science.gov (United States)

Zhu, Zhengbo; Seidel, Daniel

2016-02-19

Pyrrolidine and 1,2,3,4-tetrahydroisoquinoline (THIQ) undergo redox-neutral α-amidation with concurrent N-alkylation upon reaction with aromatic aldehydes and isocyanides. Reactions are promoted by acetic acid and represent a new variant of the Ugi reaction.

Study of Serum Drug Levels in Calves Following Intramuscular Administration of Three Tetracycline Drug Preparations

OpenAIRE

Black, W. D.; Claxton, J.; Robinson, G. A.

1982-01-01

Three antibiotic formulations, oxytetracycline (A) in propylene glycol and oxytetracycline (B) in polyvinyl pyrrolidine and pyrrolidino-methyltetracycline in an oil suspension were given to calves by the intramuscular route. Only oxytetracycline (A) appeared to cause much pain after injection.

Bis(N-ethyl-N-methyl?dithio?carbamato-?2 S,S?)diphenyl?tin(IV)

OpenAIRE

Muthalib, Amirah Faizah; Baba, Ibrahim; Ng, Seik Weng

2010-01-01

The dithio?carbamate anions in the title compound, [Sn(C6H5)2(C4H8NS2)2], chelate to the SnIV atom, which is six-coordinated in a skew-trapezoidal-bipyramidal geometry. The mol?ecule lies across a twofold rotation axis.

Bis(N-isopropyl-N-methyl-dithio-carbamato-κS,S')diphenyl-tin(IV).

Science.gov (United States)

Muthalib, Amirah Faizah; Baba, Ibrahim; Farina, Yang; Ng, Seik Weng

2010-03-03

The dithio-carbamate anions in the title compound, [Sn(C(6)H(5))(2)(C(5)H(10)NS(2))(2)], chelate to the Sn(IV) atom, which is six-coordinated in a skew-trapezoidal-bipyramidal geometry. The mol-ecule lies across a twofold rotation axis.

Bis(N-isopropyl-N-methyl?dithio?carbamato-?2 S,S?)diphenyl?tin(IV)

OpenAIRE

Muthalib, Amirah Faizah; Baba, Ibrahim; Farina, Yang; Ng, Seik Weng

2010-01-01

The dithio?carbamate anions in the title compound, [Sn(C6H5)2(C5H10NS2)2], chelate to the SnIV atom, which is six-coordinated in a skew-trapezoidal-bipyramidal geometry. The mol?ecule lies across a twofold rotation axis.

Bis(N-ethyl-N-methyl-dithio-carbamato-κS,S')diphenyl-tin(IV).

Science.gov (United States)

Muthalib, Amirah Faizah; Baba, Ibrahim; Ng, Seik Weng

2010-03-03

The dithio-carbamate anions in the title compound, [Sn(C(6)H(5))(2)(C(4)H(8)NS(2))(2)], chelate to the Sn(IV) atom, which is six-coordinated in a skew-trapezoidal-bipyramidal geometry. The mol-ecule lies across a twofold rotation axis.

Stabilization of colloidal palladium particles by a block copolymer of polystyrene and a block containing amide sidegroups

NARCIS (Netherlands)

Roescher, G.A.; Roescher, A.; Hempenius, Mark A.; Klok, H.A.; Moller, M.; Möller, M.

1996-01-01

A block copolymer of polystyrene and poly(tert-butylmethacrylate) was prepared by anionic polymerization. The ester groups of the poly(tert-butylmethacrylate) were hydrolyzed, after wich the remaining carboxyl groups were reacted with pyrrolidine. The resulting block copolymer with amide sidegroups

The use of dispersive X-ray fluorescence technique for pollution evaluation of heavy metals in water samples and lake sediments

International Nuclear Information System (INIS)

Vives, Ana Elisa Sirito de; Brienza, Sandra Maria Boscolo

2002-01-01

The energy dispersive X-ray fluorescence technique (EDXRF) was used to determine metals concentration in water and bottom sediments samples in lakes at Santa Gertrudes region, Sao Paulo state, Brazil. The studied area is about 12 ha, with several lakes formed by argil extraction and present high volume of waste which can be dangerous and cause risks to water flora and fauna and also to human health by direct or indirect contact with the residues. To evaluate contamination degree by heavy metals water samples were collected in three lakes, in 2000 July and November, corresponding to the dry and rainy season. In two lakes the sampling procedure were superficial, and in the third lake, sampling was done at central region and in different deepness. Sediment samples were collected at two lakes, in 2000, July (dry) and November (rainy). To determine biologically available metals concentration (no-residual fraction) in the sediment, an acid extraction procedure was used. To quantitative analysis of both samples, metals were pre concentrated by complexation with ammonium pyrrolidine dithiocarbamate. Samples were excited with a X-ray tube with Mo target and Zr filter, operated at 25 kV/10 mA, and X-ray characteristics measure were done with a Si(Li) semi conductor detector. In water samples, were determined the elements Fe, Cu, Zn and Pb. Among the analyzed elements, Fe presented the highest concentration, independent of the sampling local. Was verified that all the analyzed elements presented concentrations below the maximum limit allowed to waters class 2, which may be distributed to domestic provisioning, to primary contact recreation, to vegetables and fruitier plants irrigation and to the natural and/or intensive breeding (agriculture) of species destined to the alimentation. In the sediment samples were determined Fe, Co, Ni, Cu, Zn and Pb, and was observed high contents to the elements Fe, Zn and Pb and relatively low concentrations of Co, Ni and Cu. It was verified

Inhibition of nuclear factor kappa-B signaling reduces growth in medulloblastoma in vivo

Directory of Open Access Journals (Sweden)

Deckard Lindsey A

2011-04-01

Full Text Available Abstract Background Medulloblastoma is a highly malignant pediatric brain tumor that requires surgery, whole brain and spine irradiation, and intense chemotherapy for treatment. A more sophisticated understanding of the pathophysiology of medulloblastoma is needed to successfully reduce the intensity of treatment and improve outcomes. Nuclear factor kappa-B (NFκB is a signaling pathway that controls transcriptional activation of genes important for tight regulation of many cellular processes and is aberrantly expressed in many types of cancer. Methods To test the importance of NFκB to medulloblastoma cell growth, the effects of multiple drugs that inhibit NFκB, pyrrolidine dithiocarbamate, diethyldithiocarbamate, sulfasalazine, curcumin and bortezomib, were studied in medulloblastoma cell lines compared to a malignant glioma cell line and normal neurons. Expression of endogenous NFκB was investigated in cultured cells, xenograft flank tumors, and primary human tumor samples. A dominant negative construct for the endogenous inhibitor of NFκB, IκB, was prepared from medulloblastoma cell lines and flank tumors were established to allow specific pathway inhibition. Results We report high constitutive activity of the canonical NFκB pathway, as seen by Western analysis of the NFκB subunit p65, in medulloblastoma tumors compared to normal brain. The p65 subunit of NFκB is extremely highly expressed in xenograft tumors from human medulloblastoma cell lines; though, conversely, the same cells in culture have minimal expression without specific stimulation. We demonstrate that pharmacological inhibition of NFκB in cell lines halts proliferation and leads to apoptosis. We show by immunohistochemical stain that phosphorylated p65 is found in the majority of primary tumor cells examined. Finally, expression of a dominant negative form of the endogenous inhibitor of NFκB, dnIκB, resulted in poor xenograft tumor growth, with average tumor volumes

Biological activity of the alkaloids of Erythroxylum coca and Erythroxylum novogranatense

NARCIS (Netherlands)

Salemink, C.A.; Novák, M.; Khan, I.

1984-01-01

The cultivated Erythroxylum varieties E. coca var. coca, E. coca var. ipadu, E. novogranatense var. novogranatense and E. novogranatense var. truxillense contain 18 alkaloids, identified so far, belonging to the tropanes, pyrrolidines and pyridines, with cocaine as the main alkaloid. The biological

Tying up Nicotine: New Selective Competitive Antagonist of the Neuronal Nicotinic Acetylcholine Receptors

DEFF Research Database (Denmark)

Petersen, Ida Nymann; Crestey, François; Jensen, Anders A

2015-01-01

Conformational restriction of the pyrrolidine nitrogen in nicotine by the introduction of an ethylene bridge provided a potent and selective antagonist of the α4β2-subtype of the nicotinic acetylcholine receptors. Resolution by chiral SFC, pharmacological characterization of the two enantiomers...

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

The latter products reacted with DMS in the presence of PEG-600 to afford the corresponding N, N1 dimethylated derivatives 6(a-e). Volume 127 Issue 3 March 2015 pp 447-453 Regular Articles. Dithiocarbamate promoted practical synthesis of N-Aryl-2-aminobenzazoles: Synthesis of novel Aurora-A kinase inhibitor.

A new efficient synthesis of isothiocyanates from amines using di-tert-butyl dicarbonate

DEFF Research Database (Denmark)

Munch, Henrik; Hansen, Jon S.; Pittelkow, Michael

2008-01-01

Alkyl and aryl amines are converted smoothly to the corresponding isothiocyanates via the dithiocarbamates in good to excellent yields using di-tert-butyl dicarbonate (Boc(2)O) and 1-3 mol% of DMAP or DABCO as catalyst. As most of the byproducts are volatile, the work-up involves simple evaporation...

Synthesis of quarternary ammonium salts with dithiocarbamate ...

Indian Academy of Sciences (India)

were taken from PDA (Potato Dextrose Agar) slants and spore suspension was made by addition of sterili- zed distilled water. The suspension was filtered through three layers of sterilized cheese cloth under aseptic con- ditions in order to remove agar bits and mycelium. Haemocytometer was used to get spore suspension.

Fullerene-based Anchoring Groups for Molecular Electronics

DEFF Research Database (Denmark)

Martin, Christian A.; Ding, Dapeng; Sørensen, Jakob Kryger

2008-01-01

We present results on a new fullerene-based anchoring group for molecular electronics. Using lithographic mechanically controllable break junctions in vacuum we have determined the conductance and stability of single-molecule junctions of 1,4-bis(fullero[c]pyrrolidin-1-yl)benzene. The compound can...

Asymmetric synthesis of synthetic alkaloids by a tandem biocatalysis/Ugi/Pictet-Spengler-type

NARCIS (Netherlands)

Znabet, A.; Zonneveld, J.; Janssen, E.; de Kanter, F.J.J.; Helliwell, M.; Turner, N.J.; Ruijter, E.; Orru, R.V.A.

2010-01-01

We have combined the biocatalytic desymmetrization of 3,4-cis-substituted meso-pyrrolidines with an Ugi-type multicomponent reaction followed in situ by a Pictet-Spengler-type cyclization reaction sequence for the rapid asymmetric synthesis of alkaloid-like polycyclic compounds. © The Royal Society

Expedient Access to an N -phenylpyrrolidin-2-yl Heterocycle via a ...

African Journals Online (AJOL)

Expedient Access to an N -phenylpyrrolidin-2-yl Heterocycle via a Base-Induced Intramolecular aza -Michael Reaction. ... in good overall yield when employing a stoichiometric amount of base to facilitate the intramolecular aza-Michael reaction. Keywords: aza Michael, intramolecular, catalysed, piperidine, pyrrolidine, base ...

Aggregation behavior of fullerenes in aqueous solutions: a capillary electrophoresis and asymmetric flow field-flow fractionation study

NARCIS (Netherlands)

Astefanei, A.; Núñez, O.; Galceran, M.T.; Kok, W.Th.; Schoenmakers, P.J.

2015-01-01

In this work, the electrophoretic behavior of hydrophobic fullerenes [buckminsterfullerene (C-60), C-70, and N-methyl-fulleropyrrolidine (C-60-pyrr)] and water-soluble fullerenes [fullerol (C-60(OH)(24)); polyhydroxy small gap fullerene, hydrated (C-120(OH)(30)); C-60 pyrrolidine tris acid

synthesis, characterization and antibacterial studies of metal

African Journals Online (AJOL)

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Metal complexes of sulfadiazine with N-alkyl-N-phenyldithiocarbamate. Bull. Chem. Soc. Ethiop. 2013, 27(1). 81 character of the C−N bond, and this is responsible for the shift in the v(C−N) stretching vibrations. In dithiocarbamate complexes, the v(C−S) symmetrical and asymmetrical stretching vibrations are diagnostics of ...

78 FR 50147 - 2012 Liquid Chemical Categorization Updates

Science.gov (United States)

2013-08-16

... Amylene, see Pentene (all isomers) Animal acid oil Animal and Fish acid oils and distillates, n.o.s...) ether Dithiocarbamate ester (C7-C35) X Distillates: Flashed feed stocks I Straight run I Diundecyl... oil Groundnut oil Y Hazelnut oil Heartcut distillate I Heptadecane, see n-Alkanes (C10+) Heptane (all...

The Development of an Aza-C-Glycoside Library Based on a Tandem Staudinger/Aza-Wittig/Ugi Three-Component Reaction

NARCIS (Netherlands)

Wennekes, T.; Bonger, K.M.; Vogel, K.; Berg, van den S.A.; Strijland, A.; Donker-Koopman, W.E.; Aerts, J.; Marel, van der A.; Overkleeft, H.S.

2012-01-01

We report the tandem Staudinger/aza-Wittig/Ugi three-component reaction mediated synthesis of a 64-member compound library of aza-C-glycosides. The library is composed of four pyrrolidine and three piperidine scaffolds, onto which a number of functional groups is grafted to form seven sublibraries.

4′-Methyl-1H-14′,19′-dioxa-4′-azaspiro[indole-3,5′-tetracyclo[18.4.0.02,6.08,13]tetracosane]-1′(24′,8′,10′,12′,20′,22′-hexaene-2,7′(3H-dione

Directory of Open Access Journals (Sweden)

Sibi Narayanan

2012-12-01

Full Text Available In the title compound, C29H28N2O4, the indoline ring system is essentially planar, with a maximum deviation of 0.027 (2 Å; the carbonyl O atom lies 0.102 (1 Å out of the least-squares plane of the indole ring. The pyrrolidine ring adopts a C-envelope conformation, with a C atom displaced by 0.643 (2 Å from the mean plane formed by the remaining ring atoms. The pyrrolidine ring makes a dihedral angle of 86.1 (8° with the indoline ring system. In the crystal, N—H...O hydrogen bonds result in the formation of cyclic centrosymmetric dimers [R22(8]. C—H...π interactions also occur, leading to a chain along the b-axis direction. There is a rather weak π–π electron interaction between the pyrrazole and benzene rings, with a centroid–centroid distance of 3.765 (1 Å.

Active and passive vectorization of technetium{sup 99m} and {sup 188}rhenium radiopharmaceuticals for medical imaging and radiotherapy; Vectorisations active et passive de radiopharmaceutiques du technetium-99m et du rhenium-188 pour l'imagerie medicale et la therapie

Energy Technology Data Exchange (ETDEWEB)

Lepareur, N

2003-11-15

Research for new molecules for nuclear medicine is a field in constant development. Over the past few years, development of new radiopharmaceuticals for radiotherapy has renewed interest for rhenium chemistry. Indeed, its two isotopes {sup 186}Re and {sup 188}Re, owing to their ideal properties and their similitude with {sup 99m}Tc, which is widely used as a radiotracer for diagnostic imaging, seem very promising for the preparation of radiopharmaceuticals. In the first part of this manuscript, the synthesis of rhenium and technetium-99 complexes, [M(RPhCS3)2(RPhCS2)] (M = Re, Tc), is described. The preparation of technetium{sup 99m} based radiopharmaceuticals, analogues to the pondered complexes, is also described. The stability/reactivity of these complexes has been studied by exchange reactions with potential ligands, specially dithiocarbamates, and also by UV-visible absorption spectroscopy and thermogravimetry. The reactivity of the complexes towards dithiocarbamates leads to the possibility to bind biomolecules to the metallic core, via the dithiocarbamate moiety. This method represents a potential alternative to current ones using the so-called bifunctional approach. In the second part of this manuscript, a new kit formulation for the {sup 188}Re labeling of lipiodol is described, using a complex analogous to those described in the previous part. The labeled oil is a potential cure for hepatocellular carcinoma. The in vitro and in vivo stability of this {sup 188}Re-SSS lipiodol and of its analogue {sup 99m}Tc-SSS lipiodol has been studied, and also their in vivo behavior in healthy pigs. This study has shown the quasi-exclusive hepatic fixation of the radiopharmaceutical, and has proven its good stability. Its selectivity for tumors remains to be shown before trying it on humans. (author)

Active and passive vectorization of technetium99m and 188rhenium radiopharmaceuticals for medical imaging and radiotherapy

International Nuclear Information System (INIS)

Lepareur, N.

2003-11-01

Research for new molecules for nuclear medicine is a field in constant development. Over the past few years, development of new radiopharmaceuticals for radiotherapy has renewed interest for rhenium chemistry. Indeed, its two isotopes 186 Re and 188 Re, owing to their ideal properties and their similitude with 99m Tc, which is widely used as a radiotracer for diagnostic imaging, seem very promising for the preparation of radiopharmaceuticals. In the first part of this manuscript, the synthesis of rhenium and technetium-99 complexes, [M(RPhCS3)2(RPhCS2)] (M = Re, Tc), is described. The preparation of technetium 99m based radiopharmaceuticals, analogues to the pondered complexes, is also described. The stability/reactivity of these complexes has been studied by exchange reactions with potential ligands, specially dithiocarbamates, and also by UV-visible absorption spectroscopy and thermogravimetry. The reactivity of the complexes towards dithiocarbamates leads to the possibility to bind biomolecules to the metallic core, via the dithiocarbamate moiety. This method represents a potential alternative to current ones using the so-called bifunctional approach. In the second part of this manuscript, a new kit formulation for the 188 Re labeling of lipiodol is described, using a complex analogous to those described in the previous part. The labeled oil is a potential cure for hepatocellular carcinoma. The in vitro and in vivo stability of this 188 Re-SSS lipiodol and of its analogue 99m Tc-SSS lipiodol has been studied, and also their in vivo behavior in healthy pigs. This study has shown the quasi-exclusive hepatic fixation of the radiopharmaceutical, and has proven its good stability. Its selectivity for tumors remains to be shown before trying it on humans. (author)

Active and passive vectorization of technetium{sup 99m} and {sup 188}rhenium radiopharmaceuticals for medical imaging and radiotherapy; Vectorisations active et passive de radiopharmaceutiques du technetium-99m et du rhenium-188 pour l'imagerie medicale et la therapie

Energy Technology Data Exchange (ETDEWEB)

Lepareur, N

2003-11-15

Research for new molecules for nuclear medicine is a field in constant development. Over the past few years, development of new radiopharmaceuticals for radiotherapy has renewed interest for rhenium chemistry. Indeed, its two isotopes {sup 186}Re and {sup 188}Re, owing to their ideal properties and their similitude with {sup 99m}Tc, which is widely used as a radiotracer for diagnostic imaging, seem very promising for the preparation of radiopharmaceuticals. In the first part of this manuscript, the synthesis of rhenium and technetium-99 complexes, [M(RPhCS3)2(RPhCS2)] (M = Re, Tc), is described. The preparation of technetium{sup 99m} based radiopharmaceuticals, analogues to the pondered complexes, is also described. The stability/reactivity of these complexes has been studied by exchange reactions with potential ligands, specially dithiocarbamates, and also by UV-visible absorption spectroscopy and thermogravimetry. The reactivity of the complexes towards dithiocarbamates leads to the possibility to bind biomolecules to the metallic core, via the dithiocarbamate moiety. This method represents a potential alternative to current ones using the so-called bifunctional approach. In the second part of this manuscript, a new kit formulation for the {sup 188}Re labeling of lipiodol is described, using a complex analogous to those described in the previous part. The labeled oil is a potential cure for hepatocellular carcinoma. The in vitro and in vivo stability of this {sup 188}Re-SSS lipiodol and of its analogue {sup 99m}Tc-SSS lipiodol has been studied, and also their in vivo behavior in healthy pigs. This study has shown the quasi-exclusive hepatic fixation of the radiopharmaceutical, and has proven its good stability. Its selectivity for tumors remains to be shown before trying it on humans. (author)

A new continuous two-step molecular precursor route to rare-earth oxysulfides Ln2O2S

International Nuclear Information System (INIS)

De Crom, N.; Devillers, M.

2012-01-01

A continuous two-step molecular precursor pathway is designed for the preparation of rare-earth oxysulfides Ln 2 O 2 S (Ln=Y, La, Pr, Nd, Sm–Lu). This new route involves a first oxidation step leading to the rare-earth oxysulfate Ln 2 O 2 SO 4 which is subsequently reduced to the rare-earth oxysulfide Ln 2 O 2 S by switching to a H 2 –Ar atmosphere. The whole process occurs at a temperature significantly lower than usual solid state synthesis (T≤650 °C) and avoids the use of dangerous sulfur-based gases, providing a convenient route to the synthesis of the entire series of Ln 2 O 2 S. The molecular precursors consist in heteroleptic dithiocarbamate complexes [Ln(Et 2 dtc) 3 (phen)] and [Ln(Et 2 dtc) 3 (bipy)] (Et 2 dtc=N,N-diethyldithiocarbamate; phen=1,10-phenanthroline; bipy=2,2′-bipyridine) and were synthesized by a new high yield and high purity synthesis route. The nature of the molecular precursor determines the minimum synthesis temperature and influences therefore the purity of the final Ln 2 O 2 S crystalline phase. - Graphical abstract: A continuous two-step molecular precursor pathway was designed for the preparation of rare-earth oxysulfides Ln 2 O 2 S (Ln=Y, La, Pr, Nd, Sm–Lu), starting from heteroleptic dithiocarbamate complexes. The influence of the nature of the molecular precursor on the minimum synthesis temperature and on the purity of the final Ln 2 O 2 S crystalline phase is discussed. Highlights: ► A new high yield and high purity synthesis route of rare earth dithiocarbamates is described. ► These compounds are used as precursors in a continuous process leading to rare-earth oxysulfides. ► The oxysulfides are obtained under much more moderate conditions than previously described.

Comment on "An unexpected formation of the novel 7-oxa-2-azabicyclo[2.2.1]hept-5-ene skeleton during the reaction of furfurylamine with maleimides and their bioprospection using a zebrafish embryo model" by C. E. Puerto Galvis and V. V. Kouznetsov, Org. Biomol. Chem., 2013, 11, 407.

Science.gov (United States)

Zubkov, F I; Kvyatkovskaya, E A; Nikitina, E V; Amoyaw, P N-A; Kouznetsov, V V; Lazarenko, V A; Khrustalev, V N

2017-08-02

It has been proved that the reaction between furfuryl amines and N-R-maleimides leads to the formation of aza-Michael addition products - 3-(furylmethylamino)-N-R-pyrrolidine-2,5-diones, instead of 7-oxa-2-azabicyclo[2.2.1]hept-5-enes, as this journal reported previously.

ALKALOIDS OF SOME EUROPEAN AND MACARONESIAN SEDOIDEAE AND SEMPERVIVOIDEAE (CRASSULACEAE)

NARCIS (Netherlands)

STEVENS, JF; THART, H; HENDRIKS, H; MALINGRE, TM

1992-01-01

Some 22 pyrrolidine and piperdine alkaloids were detected in the leafy parts of Sedum acre, S. aetnense, S. anglicum, S. brissemoreti, S. farinosum, S. fusiforme, S. lancerottense, S. melanantherum, and S. nudum. In addition to the alkaloids known from S. acre, 1-(2-pyrrolidyl)-propan-2-one and

Non-Heme Iron Catalysts with a Rigid Bis-Isoindoline Backbone and Their Use in Selective Aliphatic C−H Oxidation

NARCIS (Netherlands)

Chen, Jianming; Lutz, Martin; Milan, Michela; Costas, Miquel; Otte, Matthias; Klein Gebbink, Bert

2017-01-01

Iron complexes derived from a bis-isoindoline-bis-pyridine ligand platform based on the BPBP ligand (BPBP=N,N′-bis(2-picolyl)-2,2′-bis-pyrrolidine) have been synthesized and applied in selective aliphatic C−H oxidation with hydrogen peroxide under mild conditions. The introduction of benzene

IBX-mediated oxidation of unactivated cyclic amines: application in highly diastereoselective oxidative Ugi-type and aza-Friedel-Crafts reactions.

Science.gov (United States)

de Graaff, C; Bensch, L; van Lint, Matthijs J; Ruijter, E; Orru, R V A

2015-10-28

The first o-iodoxybenzoic acid (IBX) mediated oxidation of unactivated amines to imines is described. A range of meso-pyrrolidines were shown to be suitable substrates. The chemical space was further explored with one-pot oxidative Ugi-type and aza-Friedel-Crafts reactions, which proved to be highly diastereoselective.

DNA-Binding Studies of Some Potential Antitumor 2,2'-bipyridine Pt(II)/Pd(II) Complexes of piperidinedithiocarbamate. Their Synthesis, Spectroscopy and Cytotoxicity.

Science.gov (United States)

Mansouri-Torshizi, Hassan; Eslami-Moghadam, Mahboube; Divsalar, Adeleh; Saboury, Ali-Akbar

2011-12-01

In this study two platinum(II) and palladium(II) complexes of the type [M(bpy)(pip-dtc)]NO3 (where M=Pt(II) or Pd(II), bpy=2,2'-bipyridine, pip-dtc=piperidinedithiocarbamate) were synthesized by reaction between diaquo-2,2'-bipyridine Pt(II)/Pd(II) nitrate and sodium salt of dithiocarbamate. These cationic water soluble complexes were characterized by elemental analysis, molar conductance, IR, electronic and 1H NMR spectroscopic studies. The cyclic dithiocarbamate was found to coordinate as bidentate fasion with Pt(II) or Pd(II) center. Their biological activities were tested against chronic myelogenous leukemia cell line, K562, at micromolar concentration. The obtained cytotoxic concentration (IC50) values were much lower than cisplatin. The interaction of these complexes with highly polymerized calf thymus DNA (ct-DNA) was extensively studied by means of electronic absorption, fluorescence, circular dichroism and other measurements. The experimental results, thermodynamic and binding parameters, suggested that these complexes cooperatively bind to DNA presumably via intercalation. Moreover, the tendency of the Pt(II) complex to interact with DNA was more than that of Pd(II) complex.

Microglial phagocytosis induced by fibrillar β-amyloid is attenuated by oligomeric β-amyloid: implications for Alzheimer's disease

Directory of Open Access Journals (Sweden)

Lin Nan

2011-06-01

Full Text Available Abstract Background Reactive microglia are associated with β-amyloid (Aβ deposit and clearance in Alzhiemer's Disease (AD. Paradoxically, entocranial resident microglia fail to trigger an effective phagocytic response to clear Aβ deposits although they mainly exist in an "activated" state. Oligomeric Aβ (oAβ, a recent target in the pathogenesis of AD, can induce more potent neurotoxicity when compared with fibrillar Aβ (fAβ. However, the role of the different Aβ forms in microglial phagocytosis, induction of inflammation and oxidation, and subsequent regulation of phagocytic receptor system, remain unclear. Results We demonstrated that Aβ(1-42 fibrils, not Aβ(1-42 oligomers, increased the microglial phagocytosis. Intriguingly, the pretreatment of microglia with oAβ(1-42 not only attenuated fAβ(1-42-triggered classical phagocytic response to fluorescent microspheres but also significantly inhibited phagocytosis of fluorescent labeled fAβ(1-42. Compared with the fAβ(1-42 treatment, the oAβ(1-42 treatment resulted in a rapid and transient increase in interleukin 1β (IL-1β level and produced higher levels of tumor necrosis factor-α (TNF-α, nitric oxide (NO, prostaglandin E2 (PGE2 and intracellular superoxide anion (SOA. The further results demonstrated that microglial phagocytosis was negatively correlated with inflammatory mediators in this process and that the capacity of phagocytosis in fAβ(1-42-induced microglia was decreased by IL-1β, lippolysaccharide (LPS and tert-butyl hydroperoxide (t-BHP. The decreased phagocytosis could be relieved by pyrrolidone dithiocarbamate (PDTC, a nuclear factor-κB (NF-κB inhibitor, and N-acetyl-L-cysteine (NAC, a free radical scavenger. These results suggest that the oAβ-impaired phagocytosis is mediated through inflammation and oxidative stress-mediated mechanism in microglial cells. Furthermore, oAβ(1-42 stimulation reduced the mRNA expression of CD36, integrin β1 (Itgb1, and Ig

ADMA induces monocyte adhesion via activation of chemokine receptors in cultured THP-1 cells.

Science.gov (United States)

Chen, Meifang; Li, Yuanjian; Yang, Tianlun; Wang, Yongjin; Bai, Yongping; Xie, Xiumei

2008-08-01

Asymmetric dimethylarginine (ADMA), an endogenous NOS inhibitor, is also an important inflammatory factor contributing to the development of atherosclerosis (AS). The present study was to test the effect of ADMA on angiotensin (Ang) II-induced monocytic adhesion. Human monocytoid cells (THP-1) or isolated peripheral blood monocyte cells (PBMCs) were incubated with Ang II (10(-6)M) or exogenous ADMA (30 microM) for 4 or 24h in the absence or presence of losartan or antioxidant PDTC. In cultured THP-1 cells, Ang II (10(-6)M) for 24h elevated the level of ADMA in the medium, upregulated the protein expression of protein arginine methyltransferase (PRMT) and decreased the activity of dimethylarginine dimethylaminohydrolase (DDAH). Both of Ang II and ADMA increased monocytic adhesion to human umbilical vein endothelial cells (HUVECs), elevated the levels of monocyte chemoattractant protein (MCP)-1, interleukin (IL)-8 and tumor necrosis factor (TNF)-alpha and upregulated CCR(2) and CXCR(2) mRNA expression, concomitantly with increase in reactive oxygen species (ROS) generation and activation of nuclear factor (NF)-kappaB. Pretreatment with losartan (10 microM) or PDTC (10 microM) abolished the effects mediated by Ang II or ADMA. In isolated PBMCs from healthy individuals, ADMA upregulated the expression of CXCR(2) mRNA, which was attenuated by losartan (10 microM), however, ADMA had no effect on surface protein expression of CCR(2). The present results suggest that ADMA may be involved in monocytic adhesion induced by Ang II via activation of chemokine receptors by ROS/NF-kappaB pathway.

Aspirin suppresses the abnormal lipid metabolism in liver cancer cells via disrupting an NFκB-ACSL1 signaling.

Science.gov (United States)

Yang, Guang; Wang, Yuan; Feng, Jinyan; Liu, Yunxia; Wang, Tianjiao; Zhao, Man; Ye, Lihong; Zhang, Xiaodong

2017-05-06

Abnormal lipid metabolism is a hallmark of tumorigenesis. Hence, the alterations of metabolism enhance the development of hepatocellular carcinoma (HCC). Aspirin is able to inhibit the growth of cancers through targeting nuclear factor κB (NF-κB). However, the role of aspirin in disrupting abnormal lipid metabolism in HCC remains poorly understood. In this study, we report that aspirin can suppress the abnormal lipid metabolism of HCC cells through inhibiting acyl-CoA synthetase long-chain family member 1 (ACSL1), a lipid metabolism-related enzyme. Interestingly, oil red O staining showed that aspirin suppressed lipogenesis in HepG2 cells and Huh7 cells in a dose-dependent manner. In addition, aspirin attenuated the levels of triglyceride and cholesterol in the cells, respectively. Strikingly, we identified that aspirin was able to down-regulate ACSL1 at the levels of mRNA and protein. Moreover, we validated that aspirin decreased the nuclear levels of NF-κB in HepG2 cells. Mechanically, PDTC, an inhibitor of NF-κB, could down-regulate ACSL1 at the levels of mRNA and protein in the cells. Functionally, PDTC reduced the levels of lipid droplets, triglyceride and cholesterol in HepG2 cells. Thus, we conclude that aspirin suppresses the abnormal lipid metabolism in HCC cells via disrupting an NFκB-ACSL1 signaling. Our finding provides new insights into the mechanism by which aspirin inhibits abnormal lipid metabolism of HCC. Therapeutically, aspirin is potentially available for HCC through controlling abnormal lipid metabolism. Copyright © 2017. Published by Elsevier Inc.

Abrasive stripping voltammetry - a new method for the study of the electrochemistry of solid materials

International Nuclear Information System (INIS)

Scholz, F.

1992-01-01

The method is applicable to electronic conductors and non-conductors. The following applications are described: Qualitative and quantitative analysis of alloys, identification of minerals, quantitative analysis of powder mixtures, identification and study of the electrochemistry of different phases in high-T c superconductor systems, determination of stability constants of metal dithiocarbamates, study of the corrosion behaviour of dental alloys. (orig.)

Identification and analytical characterization of nine synthetic cathinone derivatives N-ethylhexedrone, 4-Cl-pentedrone, 4-Cl-α-EAPP, propylone, N-ethylnorpentylone, 6-MeO-bk-MDMA, α-PiHP, 4-Cl-α-PHP, and 4-F-α-PHP.

Science.gov (United States)

Liu, Cuimei; Jia, Wei; Li, Tao; Hua, Zhendong; Qian, Zhenhua

2017-08-01

Clinical and forensic toxicology laboratories are continuously confronted by analytical challenges when dealing with the new psychoactive substances (NPS) phenomenon. In this study, the analytical characterization of nine synthetic cathinones is described: 2-(ethylamino)-1-phenylhexan-1-one (N-ethylhexedrone 1), 1-(4-chlorophenyl)-2-(methylamino)pentan-1-one (4-Cl-pentedrone 2), 1-(4-chlorophenyl)-2-(ethylamino)pentan-1-one (4-Cl-α-EAPP 3), 1-(3,4-methylenedioxyphenyl)-2-propylaminopropan-1-one (propylone 4), 1-(3,4-methylenedioxyphenyl)-2-ethylaminopentan-1-one (N-ethylnorpentylone 5), 1-(6-methoxy-3,4-methylenedioxyphenyl)-2-methylaminopropan-1-one (6-MeO-bk-MDMA 6), 4-methyl-1-phenyl-2-(pyrrolidin-1-yl)pentan-1-one (α-PiHP 7), 1-(4-chlorophenyl)-2-(pyrrolidin-1-yl)hexan-1-one (4-Cl-α-PHP 8), and 1-(4-fluorophenyl)-2-(pyrrolidin-1-yl)hexan-1-one (4-F-α-PHP 9). The identification was based on ultra-high-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UHPLC-QTOF-MS), gas chromatography-mass spectrometry (GC-MS), and nuclear magnetic resonance (NMR) spectroscopy. The mass-spectral fragmentations of these compounds following collision-induced dissociation (CID) and electron ionization (EI) were studied to assist forensic laboratories in identifying these compounds or other substances with similar structure in their case work. To our knowledge, no analytical data about the compounds 1-4, 7, and 8 have appeared until now, making this the first report on these compounds. The GC-MS data of 5, 6 and 9 has been reported, but this study added the LC-MS, Fourier Transform Infrared (FTIR) and NMR data for additional characterization. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Proline-Based Carbamates as Cholinesterase Inhibitors

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Hana Pizova

2017-11-01

Full Text Available Series of twenty-five benzyl (2S-2-(arylcarbamoylpyrrolidine-1-carboxylates was prepared and completely characterized. All the compounds were tested for their in vitro ability to inhibit acetylcholinesterase (AChE and butyrylcholinesterase (BChE, and the selectivity of compounds to individual cholinesterases was determined. Screening of the cytotoxicity of all the compounds was performed using a human monocytic leukaemia THP-1 cell line, and the compounds demonstrated insignificant toxicity. All the compounds showed rather moderate inhibitory effect against AChE; benzyl (2S-2-[(2-chlorophenylcarbamoyl]pyrrolidine-1-carboxylate (IC50 = 46.35 μM was the most potent agent. On the other hand, benzyl (2S-2-[(4-bromophenyl-] and benzyl (2S-2-[(2-bromophenylcarbamoyl]pyrrolidine-1-carboxylates expressed anti-BChE activity (IC50 = 28.21 and 27.38 μM, respectively comparable with that of rivastigmine. The ortho-brominated compound as well as benzyl (2S-2-[(2-hydroxyphenylcarbamoyl]pyrrolidine-1-carboxylate demonstrated greater selectivity to BChE. The in silico characterization of the structure–inhibitory potency for the set of proline-based carbamates considering electronic, steric and lipophilic properties was provided using comparative molecular surface analysis (CoMSA and principal component analysis (PCA. Moreover, the systematic space inspection with splitting data into the training/test subset was performed to monitor the statistical estimators performance in the effort to map the probability-guided pharmacophore pattern. The comprehensive screening of the AChE/BChE profile revealed potentially relevant structural and physicochemical features that might be essential for mapping of the carbamates inhibition efficiency indicating qualitative variations exerted on the reaction site by the substituent in the 3′-/4′-position of the phenyl ring. In addition, the investigation was completed by a molecular docking study of recombinant human AChE.

Synthesis of some glycoside analogs and related compounds from 9-amino-6-(methylthio)-9H-purine.

Science.gov (United States)

Temple, C; Kussner, C L; Montgomery, J A

1975-12-01

Additional information on the anticancer activity of 9-amino-9H-purine-6(1H)-thione and its derivatives was sought by the synthesis of some 9-(substituted amino)-6-(methylthio)-9H-purines in which the 9-substituent contained functional groups capable of either reversible or irreversible binding with an enzymatic site. Condensation of 9-amino-6-(methylthio)-9H-purine (1) with some carbonyl compounds followed by hydride reduction of the azomethine linkage in the intermediates leads to the 2-pyrrolylmethyl (8), 2,3,4-trihydroxybutyl (10), and the 1,5-dihydroxy-2- and 3-pentyl (11 and 12) compounds. A 4-hydroxybutyl derivative (13) was obtained by alkylation of 18, the 9-acetyl derivative of 1, with 4-chlorobutyl acetate followed by saponification. The cyclization of 13 and 11 with a sulfonyl chloride gave the 9-pyrrolidin-1-yl (27) and the 9-[2-(tosyloxymethyl)pyrrolidin-1-yl] (28), respectively. Acylation of 1 with ethyl L-2-pyrrolidine-5-carboxylate and ethyl 1-methyl-5-pyrrolidone-3-carboxylate, respectively, in Me2SO containing NaH gave the corresponding amides 15 and 17. Alkylation of 18 with 1-bromo-2-chloroethane and epichlorohydrin gave the N-(2-chloroethyl) and N-(1,2-epoxy-3-propyl) derivatives 19 and 20. The chloro group of the chlorobutyl derivative of 18 was displaced with KSCN and NaN3, respectively, to give the thiocyanate and azido derivatives 23 and 24. Hydrogenation of the latter gave the amine (25), which was acylated with ethyl chloroformate to give the (ethoxycarbonyl)amino compound 26. None of these compounds showed activity against L1210 leukemia cells implanted ip in mice on a single-dose schedule, suggesting that the activity observed in the simpler 9-aminopurines resulted from cleavage of the hydrazino linkage to give pH-purine-6(1H)-thione.

1-Benzyl-2-(1H-indol-3-yl-5-oxopyrrolidine-2-carbonitrile

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Raymond Schinazi

2008-02-01

Full Text Available In the title compound, C20H17N3O, a potential anti-human immunodeficiency virus type 1 (HIV-1 non-nucleoside reverse-transcriptase inhibitor, the pyrrolidine ring has an envelope conformation. In the crystal structure, adjacent molecules are connected into infinite chains via an N—H...O hydrogen bond.

Dithiocarbamate promoted practical synthesis of N-Aryl-2 ...

Indian Academy of Sciences (India)

a wide variety of disorders such as HIV,1 neuro degeneration2 and inflammatory diseases.3 Moreover,. 2-aminobenzoxazoles have also been reported as. VEGFR inhibitors and are thus important for hyper proliferative diseases such as cancer and rheumatoid arthritis.4 The 2-aminobenzothiazole compounds were.

Design of Plasmodium vivax Hypoxanthine-Guanine Phosphoribosyltransferase Inhibitors as Potential Antimalarial Therapeutics

Czech Academy of Sciences Publication Activity Database

Keough, D. T.; Rejman, Dominik; Pohl, Radek; Zborníková, Eva; Hocková, Dana; Croll, T.; Edstein, M. D.; Birrell, G. W.; Chavchich, M.; Naesens, L. M. J.; Pierens, G. K.; Brereton, I. M.; Guddat, L. W.

2018-01-01

Roč. 13, č. 1 (2018), s. 82-90 ISSN 1554-8929 R&D Projects: GA ČR(CZ) GA16-06049S; GA ČR GA15-11711S Institutional support: RVO:61388963 Keywords : plasmodium vivax * inhibitor * pyrrolidine nucleotide bisphosphonate * HXGPRT Subject RIV: CC - Organic Chemistry OBOR OECD: Organic chemistry Impact factor: 4.995, year: 2016

Crystal structures and Hirshfeld surface analyses of bis[N,N-bis(2-methoxyethyldithiocarbamato-κ2S,S′]di-n-butyltin(IV and [N-(2-methoxyethyl-N-methyldithiocarbamato-κ2S,S′]triphenyltin(IV

Directory of Open Access Journals (Sweden)

Rapidah Mohamad

2018-03-01

Full Text Available The crystal and molecular structures of the two title organotin dithiocarbamate compounds, [Sn(C4H92(C7H14NO2S22], (I, and [Sn(C6H53(C5H10NOS2], (II, are described. Both structures feature asymmetrically bound dithiocarbamate ligands leading to a skew-trapezoidal bipyramidal geometry for the metal atom in (I and a distorted tetrahedral geometry in (II. The complete molecule of (I is generated by a crystallographic twofold axis (Sn site symmetry 2. In the crystal of (I, molecules self-assemble into a supramolecular array parallel to (10-1 via methylene-C—H...O(methoxy interactions. In the crystal of (II, supramolecular dimers are formed via pairs of weak phenyl-C—H...π(phenyl contacts. In each of (I and (II, the specified assemblies connect into a three-dimensional architecture without directional interactions between them. Hirshfeld surface analyses confirm the importance of H...H contacts in the molecular packing of each of (I and (II, and in the case of (I, highlight the importance of short methoxy-H...H(butyl contacts between layers.

Synthesis and structural studies of copper sulfide nanocrystals

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Peter A. Ajibade

Full Text Available We report the synthesis and structural studies of copper sulfide nanocrystals from copper(II dithiocarbamate single molecule precursors. The optical studies of the as-prepared copper sulfide nanoparticles were carried out using UV–Visible and photoluminescence spectroscopy. The absorption spectra show absorption band edges at 287 nm and exhibit considerable blue shift that could be ascribed to the quantum confinement effects as a result of the small crystallite sizes of the nanoparticles and the photoluminescence spectra show emission curves that are red shifted with respect to the absorption band edges. The structural studies were carried out using powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy and atomic force microscopy. The XRD patterns revealed the formation of hexagonal structure of covellite CuS with estimated crystallite sizes of 17.3–18.6 nm. The TEM images showed particles with almost spherical or rod shapes with average crystallite sizes of 3–9.8 nm. SEM images showed morphology with ball-like microsphere on the surfaces and EDS spectra confirmed the presence of CuS nanoparticles. Keywords: CuS, Dithiocarbamate, Nanoparticles, Electron microscopy, AFM

Synthesis and characterization of tris[butyl-(1-methyl-3-phenyl-propyl)-dithiocarbamato]-cobalt(III) seskvitoluene

OpenAIRE

TIBOR SABO; ISMET M. HODZIC; SRECKO R. TRIFUNOVIC; VESNA M. DJINOVIC; GORAN N. KALUDJEROVIC

2002-01-01

A new bidentate ligand butyl-(1-methyl-3-phenyl-propyl)-dithiocarbamate (bmFpdtc) was prepared, as the sodium salt. In the reaction of hexaaminecobalt(III) chloride with NabmFpdtc, the corresponding tris[butyl-(1-methyl-3-phenyl-propyl)-dithiocarbamato]cobalt(III), [Co(bmFpdtc)3] complex was prepared. The complex was characterized by elemental analysis, infrared, electronic absorption, 1H and 13C-NMR spectroscopy.

Rosiglitazone attenuates NF-κB-dependent ICAM-1 and TNF-α production caused by homocysteine via inhibiting ERK1/2/p38MAPK activation

International Nuclear Information System (INIS)

Bai, Yong-Ping; Liu, Yu-Hui; Chen, Jia; Song, Tao; You, Yu; Tang, Zhen-Yan; Li, Yuan-Jian; Zhang, Guo-Gang

2007-01-01

Previous studies demonstrated an important interaction between nuclear factor-kappaB (NF-κB) activation and homocysteine (Hcy)-induced cytokines expression in endothelial cells and vascular smooth muscle cells. However, the underlying mechanism remains illusive. In this study, we investigated the effects of Hcy on NF-κB-mediated sICAM-1, TNF-α production and the possible involvement of ERK 1/2 /p38MAPK pathway. The effects of rosiglitazone intervention were also examined. Our results show that Hcy increased the levels of sICAM-1 and TNF-α in cultured human umbilical vein endothelial cells (HUVECs) in a time- and concentration-dependent manner. This effect was significantly depressed by rosiglitazone and different inhibitors (PDTC, NF-κB inhibitor; PD98059, MEK inhibitor; SB203580, p38MAPK specific inhibitor; and staurosporine, PKC inhibitor). Next, we investigated the effect of Hcy on ERK 1/2 /p38MAPK pathway and NF-κB activity in HUVECs. The results show that Hcy activated both ERK 1/2 /p38MAPK pathway and NF-κB-DNA-binding activity. These effects were markedly inhibited by rosiglitazone as well as other inhibitors (SB203580, PD98059, and PDTC). Further, the pretreatment of staurosporine abrogated ERK 1/2 /p38MAPK phosphorylation, suggesting that Hcy-induced ERK 1/2 /p38MAPK activation is associated with PKC activity. Our results provide evidence that Hcy-induced NF-κB activation was mediated by activation of ERK 1/2 /p38MAPK pathway involving PKC activity. Rosiglitazone reduces the NF-κB-mediated sICAM-1 and TNF-α production induced by Hcy via inhibition of ERK 1/2 /p38MAPK pathway

1-(4-Bromobenzoyl-2-phenylpyrrolidine-2-carboxamide

Directory of Open Access Journals (Sweden)

Vahan Martirosyan

2008-03-01

Full Text Available In the title compound, C18H17BrN2O2, which is a potential human immunodeficiency virus type 1 (HIV-1 non-nucleoside reverse transcriptase inhibitor, the pyrrolidine ring exhibits an envelope conformation. In the crystal structure, intermolecular N—H...O hydrogen bonds [N...O = 2.861 (3 Å] link the molecules into centrosymmetric dimers.

7-Chloro-11a-phenyl-2,3,5,10,11,11a-hexahydro-1H-pyrrolo[2,1-c][1,4]benzodiazepine-5,11-dione

Directory of Open Access Journals (Sweden)

Vahan Martirosyan

2008-03-01

Full Text Available The title compound, C18H15ClN2O2, is a potential human immunodeficiency virus type-1 (HIV-1 non-nucleoside reverse transcriptase inhibitor. The pyrrolidine ring adopts an envelope and the diazepine ring a boat conformation. In the crystal structure, two isomers (R and S form centrosymmetric dimers via N—H...O hydrogen bonds.

N-Iodosuccinimide-Promoted Hofmann-Löffler Reactions of Sulfonimides under Visible Light.

Science.gov (United States)

O'Broin, Calvin Q; Fernández, Patricia; Martínez, Claudio; Muñiz, Kilian

2016-02-05

Conditions for an attractive and productive protocol for the position-selective intramolecular C-H amination of aliphatic groups (Hofmann-Löffler reaction) are reported employing sulfonimides as nitrogen sources. N-Iodosuccinimide is the only required promoter for this transformation, which is conveniently initiated by visible light. The overall transformation provides pyrrolidines under mild and selective conditions as demonstrated for 17 different substrates.

Synthesis and characterization of tris[butyl-(1-methyl-3-phenyl-propyl-dithiocarbamato]-cobalt(III seskvitoluene

Directory of Open Access Journals (Sweden)

TIBOR SABO

2002-02-01

Full Text Available A new bidentate ligand butyl-(1-methyl-3-phenyl-propyl-dithiocarbamate (bmFpdtc was prepared, as the sodium salt. In the reaction of hexaaminecobalt(III chloride with NabmFpdtc, the corresponding tris[butyl-(1-methyl-3-phenyl-propyl-dithiocarbamato]cobalt(III, [Co(bmFpdtc3] complex was prepared. The complex was characterized by elemental analysis, infrared, electronic absorption, 1H and 13C-NMR spectroscopy.

Di-tert-butyl-bis(N-isopropyl-N-methyl-dithio-carbamato-κS,S')tin(IV).

Science.gov (United States)

Muthalib, Amirah Faizah; Baba, Ibrahim; Samsudin, Mohd Wahid; Ng, Seik Weng

2010-03-03

The dithio-carbamate anions in the title compound, [Sn(C(4)H(9))(2)(C(5)H(10)NS(2))(2)], chelate to the Sn(IV) atom, which is six-coordinated in a skew-trapezoidal-bipyramidal geometry. The mol-ecule lies across a twofold rotation axis. The crystal studied was a non-merohedral twin, the ratio of the twin components being 0.82 (1):0.18 (1).

Di-tert-butylbis(N-isopropyl-N-methyldithiocarbamato-κ2S,S′tin(IV

Directory of Open Access Journals (Sweden)

Amirah Faizah Muthalib

2010-04-01

Full Text Available The dithiocarbamate anions in the title compound, [Sn(C4H92(C5H10NS22], chelate to the SnIV atom, which is six-coordinated in a skew-trapezoidal-bipyramidal geometry. The molecule lies across a twofold rotation axis. The crystal studied was a non-merohedral twin, the ratio of the twin components being 0.82 (1:0.18 (1.

Crystal structures and Hirshfeld surface analyses of bis-[N,N-bis-(2-meth-oxy-eth-yl)di-thio-carbamato-κ2S,S']di-n-butyl-tin(IV) and [N-(2-meth-oxy-eth-yl)-N-methyl-dithio-carbamato-κ2S,S']tri-phenyl-tin(IV).

Science.gov (United States)

Mohamad, Rapidah; Awang, Normah; Kamaludin, Nurul Farahana; Jotani, Mukesh M; Tiekink, Edward R T

2018-03-01

The crystal and mol-ecular structures of the two title organotin di-thio-carbamate compounds, [Sn(C 4 H 9 ) 2 (C 7 H 14 NO 2 S 2 ) 2 ], (I), and [Sn(C 6 H 5 ) 3 (C 5 H 10 NOS 2 )], (II), are described. Both structures feature asymmetrically bound di-thio-carbamate ligands leading to a skew-trapezoidal bipyramidal geometry for the metal atom in (I) and a distorted tetra-hedral geometry in (II). The complete mol-ecule of (I) is generated by a crystallographic twofold axis (Sn site symmetry 2). In the crystal of (I), mol-ecules self-assemble into a supra-molecular array parallel to (10-1) via methyl-ene-C-H⋯O(meth-oxy) inter-actions. In the crystal of (II), supra-molecular dimers are formed via pairs of weak phenyl-C-H⋯π(phen-yl) contacts. In each of (I) and (II), the specified assemblies connect into a three-dimensional architecture without directional inter-actions between them. Hirshfeld surface analyses confirm the importance of H⋯H contacts in the mol-ecular packing of each of (I) and (II), and in the case of (I), highlight the importance of short meth-oxy-H⋯H(but-yl) contacts between layers.

Proteochemometric Modeling of the Interaction Space of Carbonic Anhydrase and its Inhibitors: An Assessment of Structure-based and Sequence-based Descriptors.

Science.gov (United States)

Rasti, Behnam; Namazi, Mohsen; Karimi-Jafari, M H; Ghasemi, Jahan B

2017-04-01

Due to its physiological and clinical roles, carbonic anhydrase (CA) is one of the most interesting case studies. There are different classes of CAinhibitors including sulfonamides, polyamines, coumarins and dithiocarbamates (DTCs). However, many of them hardly act as a selective inhibitor against a specific isoform. Therefore, finding highly selective inhibitors for different isoforms of CA is still an ongoing project. Proteochemometrics modeling (PCM) is able to model the bioactivity of multiple compounds against different isoforms of a protein. Therefore, it would be extremely applicable when investigating the selectivity of different ligands towards different receptors. Given the facts, we applied PCM to investigate the interaction space and structural properties that lead to the selective inhibition of CA isoforms by some dithiocarbamates. Our models have provided interesting structural information that can be considered to design compounds capable of inhibiting different isoforms of CA in an improved selective manner. Validity and predictivity of the models were confirmed by both internal and external validation methods; while Y-scrambling approach was applied to assess the robustness of the models. To prove the reliability and the applicability of our findings, we showed how ligands-receptors selectivity can be affected by removing any of these critical findings from the modeling process. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Biodistribution studies of {sup 99m}Tc-labeled myoblasts in a murine model of muscular dystrophy

Energy Technology Data Exchange (ETDEWEB)

Colombo, F.R. E-mail: colombof@policlinico.mi.it; Torrente, Y.; Casati, R.; Benti, R.; Corti, S.; Salani, S.; D' Angelo, M.G.; DeLiso, A.; Scarlato, G.; Bresolin, N.; Gerundini, P

2001-11-01

The purpose of this study was twofold: first, to evaluate the myoblast labeling of various {sup 99m}Tc complexes and to select the complex that best accomplishes this labeling, and second to evaluate the biodistribution of myoblasts labeled with this complex using mice with MDX muscular dystrophy (the murine homologue of Duchenne's muscular dystrophy). The following ligands were used to prepare the corresponding {sup 99m}Tc complexes: hexakis-methoxy-isobutyl-isonitrile (MIBI), bis(2-ethoxyethyl)diphosphinoethane (Tf), (RR,SS)-4,8-diaza-3,6,6,9-tetramethyl-undecane-2,10-dione-bisoxime (HM-PAO), bis(N-ethyl)dithiocarbamate (NEt), and bis(N-ethoxy, N-ethyl)dithiocarbamate (NOEt). One million murine myoblasts were incubated for 30-60 minutes with 5 mCi of each of the 99mTc complexes prepared from the above ligands. Viability was assessed by microscopic counting after trypan blue staining, and the radioactivity absorbed in the cells was measured after centrifugation. The compound with the highest uptake in cellular pellets was [{sup 99m}Tc]N-NOEt. The biodistribution of myoblasts labeled with this complex was evaluated after intraaortic injection in dystrophic mice. Such an approach has the potential of effecting widespread gene transfer through the bloodstream to muscles lacking dystrophin.

Biodistribution studies of 99mTc-labeled myoblasts in a murine model of muscular dystrophy

International Nuclear Information System (INIS)

Colombo, F.R.; Torrente, Y.; Casati, R.; Benti, R.; Corti, S.; Salani, S.; D'Angelo, M.G.; DeLiso, A.; Scarlato, G.; Bresolin, N.; Gerundini, P.

2001-01-01

The purpose of this study was twofold: first, to evaluate the myoblast labeling of various 99m Tc complexes and to select the complex that best accomplishes this labeling, and second to evaluate the biodistribution of myoblasts labeled with this complex using mice with MDX muscular dystrophy (the murine homologue of Duchenne's muscular dystrophy). The following ligands were used to prepare the corresponding 99m Tc complexes: hexakis-methoxy-isobutyl-isonitrile (MIBI), bis(2-ethoxyethyl)diphosphinoethane (Tf), (RR,SS)-4,8-diaza-3,6,6,9-tetramethyl-undecane-2,10-dione-bisoxime (HM-PAO), bis(N-ethyl)dithiocarbamate (NEt), and bis(N-ethoxy, N-ethyl)dithiocarbamate (NOEt). One million murine myoblasts were incubated for 30-60 minutes with 5 mCi of each of the 99mTc complexes prepared from the above ligands. Viability was assessed by microscopic counting after trypan blue staining, and the radioactivity absorbed in the cells was measured after centrifugation. The compound with the highest uptake in cellular pellets was [ 99m Tc]N-NOEt. The biodistribution of myoblasts labeled with this complex was evaluated after intraaortic injection in dystrophic mice. Such an approach has the potential of effecting widespread gene transfer through the bloodstream to muscles lacking dystrophin

Effects of pesticides on the peripheral and central nervous system in tobacco farmers in Malaysia: studies on peripheral nerve conduction, brain-evoked potentials and computerized posturography.

Science.gov (United States)

Kimura, Kaoru; Yokoyama, Kazuhito; Sato, Hajime; Nordin, Rusli Bin; Naing, Lin; Kimura, Satoshi; Okabe, Shingo; Maeno, Takashi; Kobayashi, Yasuki; Kitamura, Fumihiko; Araki, Shunichi

2005-04-01

We examined the effects of pesticides on the central and peripheral nervous system in the setting of a tobacco farm at a developing country. Maximal motor and sensory nerve conduction velocities (MCV and SCV, respectively) in the median, sural and tibial nerves, postural sway, and brain-evoked potentials (auditory event-related and visual-evoked potentials) were measured in 80 male tobacco farmers and age- and sex-matched 40 controls in Kelantan, Malaysia. Median SCV (finger-wrist) in farmers using Delsen (mancozeb, dithiocarbamate fungicide), who showed significant decrease of serum cholinesterase activities, were significantly lower compared with the controls. Sural SCV in farmers using Fastac (alpha-cypermethrin, pyrethroid insecticide) and median MCV (elbow-wrist) in farmers using Tamex (butralin, dinitroaniline herbicide) were significantly slowed compared with their respective controls. In Delsen (mancozeb, dithiocarbamate) users, the power of postural sway of 0-1 Hz was significantly larger than that in the controls both in the anterior-posterior direction with eyes open and in the right-left direction with eyes closed. The former type of sway was also significantly increased in Tamaron (methamidophos, organophosphorus insecticide) users. In conclusion, nerve conduction velocities and postural sway seem to be sensitive indicators of the effects of pesticides on the central and peripheral nervous system.

Discovery and optimization of adamantyl carbamate inhibitors of 11β-HSD1.

Science.gov (United States)

Tice, Colin M; Zhao, Wei; Krosky, Paula M; Kruk, Barbara A; Berbaum, Jennifer; Johnson, Judith A; Bukhtiyarov, Yuri; Panemangalore, Reshma; Scott, Boyd B; Zhao, Yi; Bruno, Joseph G; Howard, Lamont; Togias, Jennifer; Ye, Yuan-Jie; Singh, Suresh B; McKeever, Brian M; Lindblom, Peter R; Guo, Joan; Guo, Rong; Nar, Herbert; Schuler-Metz, Annette; Gregg, Richard E; Leftheris, Katerina; Harrison, Richard K; McGeehan, Gerard M; Zhuang, Linghang; Claremon, David A

2010-11-15

Synthesis of 2-adamantyl carbamate derivatives of piperidines and pyrrolidines led to the discovery of 9a with an IC(50) of 15.2 nM against human 11β-HSD1 in adipocytes. Optimization for increased adipocyte potency, metabolic stability and selectivity afforded 11k and 11l, both of which were >25% orally bioavailable in rat. Copyright © 2010 Elsevier Ltd. All rights reserved.

Vacuum ultraviolet photochemistry of tetrahydrothiophene and sulfolane

International Nuclear Information System (INIS)

Scala, A.A.; Colon, I.

1979-01-01

The vacuum uv photolysis of tetrahydrothiophene (THT) involves the breaking of the S to α-C bond. Besides ethylene, C 3 H 6 and 1,3-butadiene are also formed. Photolyses of THT, tetrahydrofuran, and pyrrolidine are similar. The vacuum uv photolysis of tetramethylene sulfone (sulfolane) was also studied; products are SO 2 , cyclobutane, 1-butene, and ethylene. No cis-2-butene was observed

Piracetam and TRH analogues antagonise inhibition by barbiturates, diazepam, melatonin and galanin of human erythrocyte D-glucose transport

OpenAIRE

Naftalin, Richard J; Cunningham, Philip; Afzal-Ahmed, Iram

2004-01-01

Nootropic drugs increase glucose uptake into anaesthetised brain and into Alzheimer's diseased brain. Thyrotropin-releasing hormone, TRH, which has a chemical structure similar to nootropics increases cerebellar uptake of glucose in murine rolling ataxia. This paper shows that nootropic drugs like piracetam (2-oxo 1 pyrrolidine acetamide) and levetiracetam and neuropeptides like TRH antagonise the inhibition of glucose transport by barbiturates, diazepam, melatonin and endogenous neuropeptide...

A new feruloyl amide derivative from the fruits of Tribulus terrestris.

Science.gov (United States)

Zhang, Xiaopo; Wei, Na; Huang, Jian; Tan, Yinfeng; Jin, Dejun

2012-01-01

A new feruloyl amide derivative, named tribulusamide C, was isolated from the fruits of Tribulus terrestris. Its structure was determined on the basis of spectroscopic analysis including IR, 1-D-, 2-D-NMR and HR-ESI-MS. The structure of tribulusamide C was characterised by a unit of pyrrolidine-2,5-dione, which distinguished it from other lignanamides previously isolated from the fruits of T. terrestris.

Effects of the fungicide metiram in outdoor freshwater microcosms: responses of invertebrates, primany producers and microbes

OpenAIRE

Ronghua, Lin; Buijse-Bogdan, L.L.; Rocha Dimitrov, M.; Dohmen, P.; Kosol, Sujitra; Maltby, L.; Roessink, I.; Sinkeldam, J.A.; Smidt, H.; Wijngaarden, van, R.P.A.; Brock, T.C.M.

2012-01-01

The ecological impact of the dithiocarbamate fungicide metiram was studied in outdoor freshwater microcosms, consisting of 14 enclosures placed in an experimental ditch. The microcosms were treated three times (interval 7 days) with the formulated product BAS 222 28F (Polyram®). Intended metiram concentrations in the overlying water were 0, 4, 12, 36, 108 and 324 μg a.i./L. Responses of zooplankton, macroinvertebrates, phytoplankton, macrophytes, microbes and community metabolism endpoints we...

(μ-trans-1,2-Di-4-pyridylethylene-κ2N:N′bis[bis(N,N-diisopropyldithiocarbamato-κ2S,S′zinc(II

Directory of Open Access Journals (Sweden)

Hadi D. Arman

2009-11-01

Full Text Available The dinuclear title compound, [Zn2(C7H14NS24(C12H10N2], is centrosymmetric about the central C=C bond. The five-coordinate Zn atom is bonded to two asymmetrically chelating dithiocarbamate ligands and a pyridine N atom to define an NS4 coordination geometry tending towards a square pyramid, with the N atom in the apical site. In the crystal structure, C—H...S contacts lead to supramolecular chains.

Selective separation of Cu, Zn, and As from solution by flotation techniques

International Nuclear Information System (INIS)

Stalidis, G.A.; Matis, K.A.; Lazaridis, N.K.

1989-01-01

The selective precipitation and flotation of copper, zinc, and arsenic ions from dilute aqueous solutions were investigated. Phase separation was accomplished effectively by the dissolved-air technique for the production of fine gas bubbles, and a short-chain xanthate was applied as the collector for copper ions, dialkyl-dithiocarbamate for zinc, and ferric sulfate for the pentavalent arsenic. The procedures followed were ion flotation for copper and zinc, and adsorbing colloid flotation for arsenic (without a surfactant)

Diclofenac salts, part 6: release from lipid microspheres.

Science.gov (United States)

Fini, Adamo; Cavallari, Cristina; Rabasco Alvarez, Antonio M; Rodriguez, Marisa Gonzalez

2011-08-01

The release of diclofenac (20%, w/w) was studied from lipidic solid dispersions using three different chemical forms (acid, sodium salt, and pyrrolidine ethanol salt) and two different lipid carriers (Compritol 888 ATO or Carnauba wax) either free or together with varying amounts (10%-30%, w/w) of stearic acid. Microspheres were prepared by ultrasound-assisted atomization of the molten dispersions and analyzed by scanning electron microscopy, differential scanning calorimetry, and hot stage microscopy. The effects of different formulations on the resulting drug release profiles as a function of pH were studied and the results were discussed. The formulation of the 18 systems and the chemical form of the drug were found to strongly affect the mode of the drug release. The solubility of the chemical forms in the lipid mixture is in the following order: pyrrolidine ethanol salt ≫ acid > sodium salt (according to the solubility parameters), and the nature of the systems thus obtained ranges from a matrix, for mutually soluble drug/carrier pairs, to a microcapsule, for pairs wherein mutual solubility is poor. Drug release from microspheres prepared by pure lipids was primarily controlled by diffusion, whereas the release from microspheres containing stearic acid was diffusion/erosion controlled at pH 7.4. Copyright © 2011 Wiley-Liss, Inc.

Electroencephalographic, behavioral and receptor binding correlates of phencyclinoids in the rat

International Nuclear Information System (INIS)

Mattia, A.; Marquis, K.L.; Leccese, A.P.; el-Fakahany, E.E.; Moreton, J.E.

1988-01-01

The pharmacology and structure-activity relationship of phencyclidine (PCP)-like drugs (phencyclinoids) were studied using electroencephalographic (EEG), behavioral and receptor binding techniques. The effects of PCP, 1-phenylcyclohexylamine HCl, N-methyl-1-phenycyclohexylamine HCl, N-ethyl-1-phenylcyclohexylamine HCl, N-(s-butyl)-1-phenylcyclohexylamine HCL, 1-(1-phenylcyclo-hexyl)-pyrrolidine HCl, 1-[1-(2-thienyl)cyclohexyl] piperidine HCl, 1-[1-(2-thienyl)cyclohexyl]-pyrrolidine HCl, ketamine and (+/-)-SKF 10047 were evaluated on the direct EEG and EEG spectra after acute i.v. injections (0.1-17.8 mg/kg). Similarities and differences were noted in the EEG dose-response curves. At lower doses of PCP and its analogs, low-amplitude theta waves predominated; however, at higher doses, high-amplitude, lower-frequency waves predominated. Qualitatively, the N-piperidine derivatives were similar to PCP and differed primarily in potency. The benzomorphan (+/-)-SKF 10047 produced only theta activity at doses up to 12.8 mg/kg. These EEG effects occurred in conjunction with overt behaviors including locomotion, stereotypy and ataxia, concurrently assessed via observer-based rating scales. A strong correlation (r = 0.98) was obtained between the EEG and behavioral effects and the IC50 values from [ 3 H]PCP displacement experiments using crude rat brain homogenates

Density functional study of the electronic structure of dye-functionalized fullerenes and their model donor-acceptor complexes containing P3HT

International Nuclear Information System (INIS)

Baruah, Tunna; Garnica, Amanda; Paggen, Marina; Basurto, Luis; Zope, Rajendra R.

2016-01-01

We study the electronic structure of C 60 fullerenes functionalized with a thiophene-diketo-pyrrolopyrrole-thiophene based chromophore using density functional theory combined with large polarized basis sets. As the attached chromophore has electron donor character, the functionalization of the fullerene leads to a donor-acceptor (DA) system. We examine in detail the effect of the linker and the addition site on the electronic structure of the functionalized fullerenes. We further study the electronic structure of these DA complexes with a focus on the charge transfer excitations. Finally, we examine the interface of the functionalized fullerenes with the widely used poly(3-hexylthiophene-2,5-diyl) (P3HT) donor. Our results show that all functionalized fullerenes with an exception of the C 60 -pyrrolidine [6,6], where the pyrrolidine is attached at a [6,6] site, have larger electron affinities relative to the pristine C 60 fullerene. We also estimate the quasi-particle gap, lowest charge transfer excitation energy, and the exciton binding energies of the functionalized fullerene-P3MT model systems. Results show that the exciton binding energies in these model complexes are slightly smaller compared to a similarly prepared phenyl-C 61 -butyric acid methyl ester (PCBM)-P3MT complex.

Supported L-pyrrolidine-2-carboxylic acid-4-hydrogen sulphate on ...

Indian Academy of Sciences (India)

pounds.2 Furthermore, a field of increasing interest is the synthesis of useful ... MCRs is of interest.3–5 β-Acetamido ketones .... we decide to introduce a new, simple, mild and effective .... Financial support for this study by the Research Affairs.

A Gate-to-gate Case Study of the Life Cycle Assessment of an Oil Palm Seedling

Science.gov (United States)

Muhamad, Halimah; Sahid, Ismail Bin; Surif, Salmijah; Ai, Tan Yew; May, Choo Yuen

2012-01-01

The palm oil industry has played an important role in the economic development of Malaysia and has enhanced the economic welfare of its people. To determine the environmental impact of the oil palm seedling at the nursery stage, information on inputs and outputs need to be assessed. The oil palm nursery is the first link in the palm oil supply chain. A gate-to-gate study was carried out whereby the system boundary was set to only include the process of the oil palm seedling. The starting point was a germinated seed in a small polyethylene bag (6 in × 9 in) in which it remained until the seedling was approximately 3 to 4 months old. The seedling was then transferred into a larger polyethylene bag (12 in × 15 in), where it remained until it was 10–12 months old, when it was planted in the field (plantation). The functional unit for this life cycle inventory (LCI) is based on the production of one seedling. Generally, within the system boundary, the production of an oil palm seedling has only two major environmental impact points, the polybags used to grow the seedling and the fungicide (dithiocarbamate) used to control pathogenic fungi, as both the polybags and the dithiocarbamate are derived from fossil fuel. PMID:24575222

Exposure of rat hippocampal astrocytes to Ziram increases oxidative stress.

Science.gov (United States)

Matei, Ann-Marie; Trombetta, Louis D

2016-04-01

Pesticides have been shown in several studies to be the leading candidates of environmental toxins and may contribute to the pathogenesis of several neurodegenerative diseases. Ziram (zinc-bis(dimethyldithiocarbamate)) is an agricultural dithiocarbamate fungicide that is used to treat a variety of plant diseases. In spite of their generally acknowledged low toxicity, dithiocarbamates are known to cause a wide range of neurobehavioral effects as well as neuropathological changes in the brain. Astrocytes play a key role in normal brain physiology and in the pathology of the nervous system. This investigation studied the effects of 1.0 µM Ziram on rat hippocampal astrocytes. The thiobarbituric acid reactive substance assay performed showed a significant increase in malondialdehyde, a product of lipid peroxidation, in the Ziram-treated cells. Biochemical analysis also revealed a significant increase in the induction of 70 kDa heat shock and heme oxygenase 1 stress proteins. In addition, an increase of glutathione peroxidase (GPx) and a significant increase in oxidized glutathione (GSSG) were observed in the Ziram-treated cells. The ratio GSH to GSSG calculated from the treated cells was also decreased. Light and transmission electron microscopy supported the biochemical findings in Ziram-treated astrocytes. This data suggest that the cytotoxic effects observed with Ziram treatments may be related to the increase of oxidative stress. © The Author(s) 2013.

A solvent extraction technique for the isotopic measurement of dissolved copper in seawater

Energy Technology Data Exchange (ETDEWEB)

Thompson, Claire M., E-mail: claire.thompson@anu.edu.au; Ellwood, Michael J., E-mail: michael.ellwood@anu.edu.au; Wille, Martin, E-mail: martin.wille@uni-tuebingen.de

2013-05-02

Graphical abstract: -- Highlights: •A new sample preparation method for seawater copper isotopic analysis (δ{sup 65}Cu). •Solvent-extraction was used to pre-concentrate metals from seawater samples. •Anion-exchange was used to purify copper from the metal-rich extract. •δ{sup 65}Cu was measured in the north Tasman Sea. •Seawater δ{sup 65}Cu may be linked to marine biological activity. -- Abstract: Stable copper (Cu) isotope geochemistry provides a new perspective for investigating and understanding Cu speciation and biogeochemical Cu cycling in seawater. In this work, sample preparation for isotopic analysis employed solvent-extraction with amino pyrollidine dithiocarbamate/diethyl dithiocarbamate (APDC/DDC), coupled with a nitric acid back-extraction, to concentrate Cu from seawater. This was followed by Cu-purification using anion-exchange. This straightforward technique is high yielding and fractionation free for Cu and allows precise measurement of the seawater Cu isotopic composition using multi-collector inductively coupled plasma mass-spectrometry. A deep-sea profile measured in the oligotrophic north Tasman Sea shows fractionation in the Cu isotopic signature in the photic zone but is relatively homogenised at depth. A minima in the Cu isotopic profile correlates with the chlorophyll a maximum at the site. These results indicate that a range of processes are likely to fractionate stable Cu isotopes in seawater.

The 5-Endo-trig Cyclization of D-Glucose Derived γ-Alkenylamines with Mercury (II Salts: Synthesis of 1-Deoxycastanospermine and its 8a-epi-Analogueâ€

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S. Jachak

2005-08-01

Full Text Available The intramolecular aminomercuration of γ-alkenylamines 1a, 1b and 4 was shown to afford the 5-endo-trig cyclized product exclusively in good yield. The utility of pyrrolidine derivatives thus obtained from D-glucose derived γ-alkenylamines 1a and 1b was demonstrated in the synthesis of 1-deoxycastanospermine (3a and 1-deoxy-8a-epi- castanospermine (3b.

Facile and Green Synthesis of Saturated Cyclic Amines

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Arruje Hameed

2017-10-01

Full Text Available Single-nitrogen containing saturated cyclic amines are an important part of both natural and synthetic bioactive compounds. A number of methodologies have been developed for the synthesis of aziridines, azetidines, pyrrolidines, piperidines, azepanes and azocanes. This review highlights some facile and green synthetic routes for the synthesis of unsubstituted, multisubstituted and highly functionalized saturated cyclic amines including one-pot, microwave assisted, metal-free, solvent-free and in aqueous media.

Catalytic enantioselective alkene aminohalogenation/cyclization involving atom transfer.

Science.gov (United States)

Bovino, Michael T; Chemler, Sherry R

2012-04-16

Problem solved: the title reaction was used for the synthesis of chiral 2-bromo, chloro, and iodomethyl indolines and 2-iodomethyl pyrrolidines. Stereocenter formation is believed to occur by enantioselective cis aminocupration and C-X bond formation is believed to occur by atom transfer. The ultility of the products as versatile synthetic intermediates was demonstrated, as was a radical cascade cyclization sequence. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

CD44+/CD24- breast cancer cells exhibit phenotypic reversion in three-dimensional self-assembling peptide RADA16 nanofiber scaffold

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Mi K

2015-04-01

formation assay further supported of the functional changes caused by the reversion in 3D RADA16 culture. Expression levels of intercellular surface adhesion molecule-1 were upregulated in cells cultured in RADA16 scaffolds, and the NF-kappa B inhibitor pyrrolidine dithiocarbamate could inhibit RADA16-induced upregulation of intercellular surface adhesion molecule-1 and the phenotype reversion of MDA-MB-453S cells.Conclusion: Culturing a CD44+/CD24--enriched breast cancer cell population in 3D RADA16 peptide nanofiber scaffold led to a significant phenotypic reversion compared with Matrigel and collagen I. Keywords: 3D culture, phenotype, reversion

Design, Synthesis and Characterization of Novel Arylamides Containing 1,2,4-triazole Nuclei for Possible Antimicrobial Activity

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S. R. Dhol

2004-01-01

Full Text Available Diphenyl aceto hydrazide on reaction with carbon disulfide and potassium hydroxide gave potassium α,α-diphenyl acetamido dithiocarbamate, which on cyclisation with hydrazine hydrate yielded key intermediate 3-mercapto-4,N-amino-5-benzhydryl-1,2,4-triazoles. The key intermediate on condensation with different acid chloride afforded our titled compounds. The synthesised compounds have been confirmed elemental analyses and further supported by spectral data. All the synthesised compounds have been evaluated for their in vitroin vitro antimicrobial activity.

Use of chelating agents as immovable phase in extraction chromatography

International Nuclear Information System (INIS)

Sebesta, F.

1978-01-01

Extraction chromatography using chelating agents is reviewed. The theory of element extraction by chelating agents and factors influencing this process (pH, extracting agent concentration in organic phase, masking agent concentration in aqueous phase) are briefly considered. The effect of kinetic factors on the extraction chromatography process is discussed. Ways of preparing columns are emphasized. Examples of using chelating reagents in various extraction chromatography systems are given. β-Diketones, oximes, hydroxamic acids, dithizon, diethyl dithiocarbamic acid are chosen as chelating agents

Determination of Cr(VI) and Cr(III) in urine and dextrose by inductively coupled plasma emission spectroscopy

Science.gov (United States)

Mianzhi, Zhuang; Barnes, Ramon M.

The determination of Cr(VI) and Cr(III) in human urine and in commercial dextrose solution is performed by induclively coupled plasma-atomic emission spectroscopy after selective preconcentration of the chromium species at different pH values by poly(dithiocarbamate) and poly(acrylamidoxime) chelating resins. The chelating properties of these resins with chromium, including the kinetics of uptake and removal of Cr(III), and the influence of matrix concentrations were evaluated. Chromium in human urine was found to exist exclusively as Cr(III).

The unexpected product of Diels-Alder reaction between "indanocyclon" and maleimide

Science.gov (United States)

Dobrowolski, Michał A.; Roszkowski, Piotr; Struga, Marta; Szulczyk, Daniel

2017-02-01

A heterocyclic compound commonly known as "indanocyclon" undergoes an unexpected Diels-Alder addition with maleimide. The resulting product has been isolated and characterized in order to get an information about its structure and possible mechanism of the reaction. Extensive comparison of single crystal properties of 3-(2,8-dioxo-1,3-diphenyl-2,8-dihydrocyclopenta[a]inden-8a(1H)-yl)pyrrolidine-2,5-dione and favorable product of the reaction has been also performed.

Unusual reactions of diazocarbonyl compounds with α,β-unsaturated δ-amino esters: Rh(II-catalyzed Wolff rearrangement and oxidative cleavage of N–H-insertion products

Directory of Open Access Journals (Sweden)

Valerij A. Nikolaev

2016-08-01

Full Text Available Rh(II-сatalyzed reactions of aroyldiazomethanes, diazoketoesters and diazodiketones with α,β-unsaturated δ-aminoesters, in contrast to reactions of diazomalonates and other diazoesters, give rise to the Wolff rearrangement and/or oxidative cleavage of the initially formed N–H-insertion products. These oxidation processes are mediated by Rh(II catalysts possessing perfluorinated ligands. The formation of pyrrolidine structures, characteristic for catalytic reactions of diazoesters, was not observed in these processes at all.

Synthesis, Characterization and Biological Activities of Novel (E)-3-(1-(Alkyloxyamino)ethylidene)-1-alkylpyrrolidine-2,4-dione Derivatives

Energy Technology Data Exchange (ETDEWEB)

Zhu, Zhao Yong; Shi, Qing Ming; Han, Bao Feng; Wang, Xian Feng; Qiang, Sheng; Yang, Chun Long [Nanjing Agricultural University, Nanjing (China)

2010-09-15

Twenty novel tetramic acid derivatives (E)-3-(1-(alkyloxyamino)ethylidene)-1-alkylpyrrolidine-2,4-diones were synthesized by the reaction of 3-(1-hydroxyethylidene)pyrrolidine-2,4-diones with O-alkyl hydroxylamines. The title compounds were confirmed by IR, {sup 1}H NMR, MS and elemental analysis. The structure of compound 6r was further verified by X-ray diffraction crystallography. The bioassays showed that most of the title compounds exhibited noticeable herbicidal and fungicidal activities.

Radical cascades using enantioenriched 7-azabenzonorbornenes and their applications in synthesis

Directory of Open Access Journals (Sweden)

2008-10-01

Full Text Available Tandem deoxygenation–neophyl-type radical rearrangement–electrophile trapping using xanthates from 7-azabenzonorbornadienes gives 3-exo-substituted 2-aza-5,6-benzonorbornenes, which in some cases undergo isomerisation to (aminomethylindenes. The starting xanthates are accessible in good yields and high enantiomeric ratios via asymmetric hydroboration of (aryne/pyrrole-derived 7-azabenzonorbornadienes. Oxidation (using RuO4 and Birch reduction of the 2-aza-5,6-benzonorbornenes provide access to substituted pyrrolidines and tetrahydroindenes, respectively.

Recent developments in the synthesis of five- and six-membered heterocycles using molecular iodine

Digital Repository Service at National Institute of Oceanography (India)

Parvatkar, P.T.; Parameswaran, P.S.; Tilve, S.G.

obtained from reaction of 2-vinyl phenyl lithium with carbonyl compounds (Scheme 4). In case of electron donating group (R 2 = OMe) on the aryl ring, the yield was found to decrease. The resulting (1-iodomethyl)-1,3- dihydroisobenzofurans... and 18. Functional group manipulations with AgOAc proceeds via the corresponding aziridinium ion. Further deprotection gave access to polyhydroxylated pyrrolidines. Interestingly, iodocyclization of (3R)-configured β-amino esters (3R,αS)-19 and (3R...

The effect of nucleotides and adenosine on stimulus-evoked glutamate release from rat brain cortical slices

OpenAIRE

Bennett, Gillian C; Boarder, Michael R

2000-01-01

Evidence has previously been presented that P1 receptors for adenosine, and P2 receptors for nucleotides such as ATP, regulate stimulus-evoked release of biogenic amines from nerve terminals in the brain. Here we investigated whether adenosine and nucleotides exert presynaptic control over depolarisation-elicited glutamate release.Slices of rat brain cortex were perfused and stimulated with pulses of 46 mM K+ in the presence of the glutamate uptake inhibitor L-trans-pyrrolidine-2,4-dicarboxyl...

2′-Methyl-2′-nitro-1′-phenyl-2′,3′,5′,6′,7′,7a'-hexahydrospiro[indoline-3,3′-1′H-pyrrolizin]-2-one

Directory of Open Access Journals (Sweden)

Yaghoub Sarrafi

2008-08-01

Full Text Available The title compound, C21H21N3O3, was synthesized by a multi-component 1,3-dipolar cycloaddition of azomethine ylide, derived from isatin and proline by a decarboxylative route, and (E-1-phenyl-2-nitropropene. In the molecule, the spiro junction links a planar oxindole ring and a pyrrolidine ring in an envelope conformation. The molecular packing is stabilized by an intermolecular N—H...N interaction of the oxindole and pyrrolizidine rings.

Thermodynamics of adsorption of dithiocarbamates at the hanging mercury drop.

Science.gov (United States)

Giannakopoulos, Evangelos; Deligiannakis, Yiannis

2007-02-27

Two dimethyldithiocarbamate (DMDTC) pesticides, thiram and ziram, are adsorbed onto a Hg drop via an entropically driven process. The adsorption isotherms are described by the Frumkin equation. For both molecules, the adsorption is characterized by a nonlinear pseudosigmoid temperature dependence of the Gibbs free energy. For the temperature range of 273-313 K, DeltaGADS varies between -43.4 and -56.71 kJ/mol for thiram and -42.60 and -55.67 kJ/mol for ziram. This variation of DeltaGADS reveals that the adsorption strength is increased at higher temperatures. During the adsorption of either molecule, strong lateral interactions are developed between neighboring adsorbates, which are severely weakened as the temperature increases. A unified reaction scheme is suggested for both ziram and thiram that predicts the formation and adsorption of a surface complex, (DMDTC)2Hg. In the case of thiram, two DMDTC molecules are formed by the cleavage of the disulfide S-S bond near the Hg electrode. The thermodynamic and structural parameters reveal that there are two limiting thermodynamic regimes for the adsorbed (DMDTC)2Hg species that originate from two limiting adsorption conformations of the adsorbates on the Hg surface. A transition occurs between these two conformations at temperatures in the region of 285-295 K. This transition is accompanied by large entropic and enthalpic changes.

Electron spin resonance of vanadium(4)-thallium(1) dithiocarbamate complexes

International Nuclear Information System (INIS)

Ivanov, A.V.; Solozhenkin, P.M.; Baratova, Z.R.; Klyashtornyj, V.B.; Uskov, V.Yu.

1990-01-01

Heteronuclear vanadium(4), thallium(1) dithiocarbanate complexes of the composition TlVO(Dtc) 3 and Tl 2 VO(Dtc) 4 under conditions of magnetic dilution were studied by ESR spectroscopy. Magnetically diluted complexes were prepared by coprecipitation from aqueous solutions of thallium(1) and oxovanadium(2) by solutions of sodium diethyldithiocarbamate, dibutyldithiocarbamate, hexamethylenedithiocarbamate, taken in superstoichiometric excess. Analysis of parameters of ESR spectra of the complexes synthesized shows that thallium atoms are not included in the first coordination sphere of oxovanadium(2), and chelate node VS 4 in thallium(1) complex lattice practically preserves its plane quadratic structure

Identification of phase I and II metabolites of the new designer drug α-pyrrolidinohexiophenone (α-PHP) in human urine by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS).

Science.gov (United States)

Paul, Michael; Bleicher, Sergej; Guber, Susanne; Ippisch, Josef; Polettini, Aldo; Schultis, Wolfgang

2015-11-01

Pyrrolidinophenones represent one emerging class of newly encountered drugs of abuse, also known as 'new psychoactive substances', with stimulating psychoactive effects. In this work, we report on the detection of the new designer drug α-pyrrolidinohexiophenone (α-PHP) and its phase I and II metabolites in a human urine sample of a drug abuser. Determination and structural elucidation of these metabolites have been achieved by liquid chromatography electrospray ionisation quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS). By tentative identification, the exact and approximate structures of 19 phase I metabolites and nine phase II glucuronides were elucidated. Major metabolic pathways revealed the reduction of the ß-keto moieties to their corresponding alcohols, didesalkylation of the pyrrolidine ring, hydroxylation and oxidation of the aliphatic side chain leading to n-hydroxy, aldehyde and carboxylate metabolites, and oxidation of the pyrrolidine ring to its lactam followed by ring cleavage and additional hydroxylation, reduction and oxidation steps and combinations thereof. The most abundant phase II metabolites were glucuronidated ß-keto-reduced alcohols. Besides the great number of metabolites detected in this sample, α-PHP is still one of the most abundant ions together with its ß-keto-reduced alcoholic dihydro metabolite. Monitoring of these metabolites in clinical and forensic toxicology may unambiguously prove the abuse of the new designer drug α-PHP. Copyright © 2015 John Wiley & Sons, Ltd.

Why does anatabine, but not nicotine, accumulate in jasmonate-elicited cultured tobacco BY-2 cells?

Science.gov (United States)

Shoji, Tsubasa; Hashimoto, Takashi

2008-08-01

Suspension-cultured cells of Nicotiana tabacum cv. Bright Yellow-2 (BY-2) grow rapidly in a highly homogenous population and still exhibit the general behavior of plant cells, and thus are often used as model systems in several areas of plant molecular and cellular biology, including secondary metabolism. While the parental tobacco variety synthesizes nicotine as a major alkaloid, the cultured tobacco cells mainly produce a related alkaloid anatabine, instead of nicotine, when elicited with jasmonates. We report here that cultured BY-2 cells scarcely express N-methylputrescine oxidase (MPO) genes even after jasmonate elicitation. MPO is the second enzyme in the biosynthetic pathway that supplies the pyrrolidine moiety of nicotine and nornicotine, but is predicted to be dispensable for the biosynthesis of anatabine, anabasine and anatalline, which do not contain the pyrrolidine moiety. When MPO was overexpressed in tobacco BY-2 cells, nicotine synthesis was dramatically enhanced while anatabine formation was effectively suppressed. As a complementary approach, we suppressed MPO expression by RNA interference in tobacco hairy roots that normally accumulate nicotine. In the MPO-suppressed roots, the contents of anatabine, anabasine and anatalline, as well as N-methylputrescine and putrescine, markedly increased to compensate for suppressed formation of nicotine and nornicotine. These results identify the transcriptional regulation of MPO as a critical rate-limiting step that restricts nicotine formation in cultured tobacco BY-2 cells.

Ruthenium-bipyridine complexes bearing fullerene or carbon nanotubes: synthesis and impact of different carbon-based ligands on the resulting products.

Science.gov (United States)

Wu, Zhen-yi; Huang, Rong-bin; Xie, Su-yuan; Zheng, Lan-sun

2011-09-07

This paper discusses the synthesis of two carbon-based pyridine ligands of fullerene pyrrolidine pyridine (C(60)-py) and multi-walled carbon nanotube pyrrolidine pyridine (MWCNT-py) via 1,3-dipolar cycloaddition. The two complexes, C(60)-Ru and MWCNT-Ru, were synthesized by ligand substitution in the presence of NH(4)PF(6), and Ru(II)(bpy)(2)Cl(2) was used as a reaction precursor. Both complexes were characterized by mass spectroscopy (MS), elemental analysis, nuclear magnetic resonance (NMR) spectroscopy, infrared spectroscopy (IR), ultraviolet/visible spectroscopy (UV-VIS) spectrometry, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and cyclic voltammetry (CV). The results showed that the substitution way of C(60)-py is different from that of MWCNT-py. The C(60)-py and a NH(3) replaced a Cl(-) and a bipyridine in Ru(II)(bpy)(2)Cl(2) to produce a five-coordinate complex of [Ru(bpy)(NH(3))(C(60)-py)Cl]PF(6), whereas MWCNT-py replaced a Cl(-) to generate a six-coordinate complex of [Ru(bpy)(2)(MWCNT-py)Cl]PF(6). The cyclic voltammetry study showed that the electron-withdrawing ability was different for C(60) and MWCNT. The C(60) showed a relatively stronger electron-withdrawing effect with respect to MWCNT. This journal is © The Royal Society of Chemistry 2011

Herbicide and pesticide occurrence in the soils of children's playgrounds in Sarajevo, Bosnia and Herzegovina.

Science.gov (United States)

Sapcanin, Aida; Cakal, Mirsada; Imamovic, Belma; Salihovic, Mirsada; Pehlic, Ekrem; Jacimovic, Zeljko; Jancan, Gordan

2016-08-01

Pesticide pollution in Sarajevo public playgrounds is an important health and environmental issue, and the lack of information about it is causing concerns amongst the general population as well as researchers. Since children are in direct contact with surface soils on children's playgrounds, such soils should be much more carefully examined. Furthermore, herbicides and pesticides get transmitted from soil surfaces brought from outside the urban areas, or they get dispersed following their direct applications in urban areas. Infants' and children's health can be directly affected by polluted soils because of the inherent toxicity and widespread use of the different pesticides in urban environments such as playgrounds. In addition to that, the presence of chromated copper arsenate (CCA) wood preservative pesticide found as soil pollutant in playing equipment was also documented. Soil samples from playgrounds were collected and analyzed for triazines, carbamates, dithiocarbamates, phenolic herbicides and organochlorine pesticides. Samples for the determination of heavy metals Cu, Cr and As were prepared by microwave-assisted acid digestion, and the findings were determined by using an inductively coupled plasma optical emission spectrometer. Triazines, carbamates, dithiocarbamates, chlorphenoxy compounds, phenolic herbicides, organochlorine pesticides and organotin compounds were detected in playground soils and their determined concentrations (mg/kg) were respectively found as follows: herbicides and pesticides on human health, which strengthens the case for a more preventative and protective approach to the uncontrolled presence of herbicides and pesticides in Sarajevo's playground soils.

Reactivities of some thiol collectors and their interactions with Ag (+1) ion by molecular modeling

International Nuclear Information System (INIS)

Yekeler, Hulya; Yekeler, Meftuni

2004-01-01

The most commonly used collectors for sulfide minerals in the mining industry are the thiol collectors for the recovery of these minerals from their associated gangues by froth flotation. For this reason, a great deal of attention has been paid to understand the attachment mechanism of thiol collectors to metal sulfide surfaces. The density functional theory (DFT) calculations at the B3LYP/3-21G* and B3LYP/6-31++G** levels were employed to propose the flotation responses of these thiol collectors, namely, diethyl dithiocarbamate, ethyl dithiocarbamate, ethyl dithiocarbonate, ethyl trithiocarbonate and ethyl dithiophosphate ions, and to study the interaction energies of these collectors with Ag (+1) ion in connection to acanthite (Ag 2 S) mineral. The calculated interaction energies, ΔE, were interpreted in terms of the highest occupied molecular orbital (HOMO) energies of the isolated collector ions. The results show that the HOMOs are strongly localized to the sulfur atoms and the HOMO energies can be used as a reactivity descriptor for the flotation ability of the thiol collectors. Using the HOMO and ΔE energies, the reactivity order of the collectors is found to be (C 2 H 5 ) 2 NCS 2 - > C 2 H 5 NHCS 2 - > C 2 H 5 OCS 2 - > C 2 H 5 SCS 2 - > (C 2 H 5 O)(OH)PS 2 - . The theoretically obtained results are in good agreement with the experimental data reported

Intramolecular Redox-Mannich Reactions: Facile Access to the Tetrahydroprotoberberine Core.

Science.gov (United States)

Ma, Longle; Seidel, Daniel

2015-09-07

Cyclic amines such as pyrrolidine undergo redox-annulations with 2-formylaryl malonates. Concurrent oxidative amine α-CH bond functionalization and reductive N-alkylation render this transformation redox-neutral. This redox-Mannich process provides regioisomers of classic Reinhoudt reaction products as an entry to the tetrahydroprotoberberine core, enabling the synthesis of (±)-thalictricavine and its epimer. An unusually mild amine-promoted dealkoxycarbonylation was discovered in the course of these studies. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Coordination chemistry of the {sup 212}Pb/{sup 212}Bi nuclear transformation: Alpha-emitting radiopharmaceuticals. Final technical report

Energy Technology Data Exchange (ETDEWEB)

Parks, N.J.; Harris, W.R.; Keen, C.L.; Cooper, S.R.

1992-07-01

Subdivisions of this project are: (a) the synthesis of prototypical thiolate and dithiocarbamate based hexacoordinate complexes, (b) radiochemical engineering for generation of no-carrier-added lead and bismuth radioelements, (c) the first isolation of bismuth-binding proteins from in vivo studies with cyclotron produced {sup 205/206}Bi tracer, and (d) initial development of transport mechanisms for the intracellular radiobiological study of alpha emitting bismuth, and (e) the initiation of chemical equilibrium studies and biochemical pathways with cyclotron-produced, no-carrier-added, {sup 203}Pb (T{sub 1/2} = 51 hr).

Coordination chemistry of the sup 212 Pb/ sup 212 Bi nuclear transformation: Alpha-emitting radiopharmaceuticals

Energy Technology Data Exchange (ETDEWEB)

Parks, N.J.; Harris, W.R.; Keen, C.L.; Cooper, S.R.

1992-07-01

Subdivisions of this project are: (a) the synthesis of prototypical thiolate and dithiocarbamate based hexacoordinate complexes, (b) radiochemical engineering for generation of no-carrier-added lead and bismuth radioelements, (c) the first isolation of bismuth-binding proteins from in vivo studies with cyclotron produced {sup 205/206}Bi tracer, and (d) initial development of transport mechanisms for the intracellular radiobiological study of alpha emitting bismuth, and (e) the initiation of chemical equilibrium studies and biochemical pathways with cyclotron-produced, no-carrier-added, {sup 203}Pb (T{sub 1/2} = 51 hr).

Mercury determination in geological samples using radiochemical separation

International Nuclear Information System (INIS)

Goncalves, Cristina; Favaro, Deborah I.T.

1997-01-01

In this work, a radiochemical procedure is presented to increase the neutron activation analysis sensitivity. After irradiation, geological reference materials - Buffalo River Sediment (BRS- - NIST SRM 2704), Lake Sediment (BCR - CRM 280) and GXR-5 (USGS - AEG) - were leached with aqua regia in a Parr bomb placed in a domestic microwave oven and then bismuth diethyl dithiocarbamate was used to pre concentrate mercury by solvent extraction. This procedure eliminates the interference from 279 keV Se-75 photopeak and background radiation from 511 keV Cu-64 photopeak. (author). 15 refs., 2 figs., 1 tab

Coordination chemistry of the 212Pb/212Bi nuclear transformation: Alpha-emitting radiopharmaceuticals

International Nuclear Information System (INIS)

Parks, N.J.; Harris, W.R.; Keen, C.L.; Cooper, S.R.

1992-07-01

Subdivisions of this project are: (a) the synthesis of prototypical thiolate and dithiocarbamate based hexacoordinate complexes, (b) radiochemical engineering for generation of no-carrier-added lead and bismuth radioelements, (c) the first isolation of bismuth-binding proteins from in vivo studies with cyclotron produced 205/206 Bi tracer, and (d) initial development of transport mechanisms for the intracellular radiobiological study of alpha emitting bismuth, and (e) the initiation of chemical equilibrium studies and biochemical pathways with cyclotron-produced, no-carrier-added, 203 Pb (T 1/2 = 51 hr)

Antiradiation compounds XV: condensations of carbon disulfide with amino, chloro, cyanomethyl, and sulfonamido heterocycles

International Nuclear Information System (INIS)

Foye, W.O.; Kauffman, J.M.; Lanzillo, J.J.; LaSala, E.F.

1975-01-01

Condensations of carbon disulfide were carried out with amino, chloro, and diamino heterocycles to give condensed ring thiazoline-2-thiones and imidazoline-2-thiones, with cyanomethyl heterocycles to give dithio acid derivatives, and with heterocyclic sulfonamides to give sulfonyldithiocarbamates. Of several examples tested, pyrido[3,2-d]thiazoline-2-thione, disodium 2-(5-chloro-2-thienyl)-3,3-dimercaptoacrylonitrile, triethylammonium 4-sulfamoylphenyldithiocarbamate, ammonium β-phenethyldithiocarbamate, and methyl N-(thiophene-2-sulfonyl)dithiocarbamate, only the last-named compound showed any radiation protection for mice. Several compounds gave negative tests for antimalarial activity

Synthesis and biological evaluation of a novel 99mTc-labelled MPP

International Nuclear Information System (INIS)

Lin Yan; Zhang Junbo; Tang Zhigang; Wang Xuebin; Zhang Xianzhong

2008-01-01

The 5-HT 1A receptor is tightly implicated in numerous mental illnesses, such as depression, anxiety, eating disorders and so on. Thus, it has become a key target for various efforts in developing in vivo imaging agents. Many efforts have been focused on the development of 99m Tc labeled 5-HT 1A receptor-bound radiotracer. In this study, a dithiocarbamate ligand containing the MPP ((2-methoxyphenyl)piperazine) moiety was labeled with [ 99m TcN] 2+ core and evaluated as potential imaging agent for 5-HT 1A receptor. (authors)

A review of pitfalls and progress in chelation treatment of metal poisonings

DEFF Research Database (Denmark)

Andersen, Ole; Aaseth, Jan

2016-01-01

to clinical settings. Intramuscular administration of dimercaptopropanol (BAL) has until now been used in acute arsenic, lead, and mercury poisonings, but repeated BAL administration increased the brain uptake of As, Pb and Hg in experimental animals. Also, diethyl dithiocarbamate (DDC) has been used...... as antidote in acute experimental animal parenteral Cd poisoning, and both DDC and tetraethylthiuram disulfide (TTD, disulfiram, Antabuse) have been used in nickel allergic patients. However, even one dose of DDC given immediately after oral Cd or Ni increased their brain uptake considerably. The calcium salt...

Redetermination of tetrakis(N,N-diethyldithiocarbamatotin(IV

Directory of Open Access Journals (Sweden)

Coco K. Y. A. Okio

2009-06-01

Full Text Available The crystal structure of the title compound, [Sn(C5H10NS24], was originally determined by Harreld & Schlemper [Acta Cryst. (1971, B27, 1964–1969] using intensity data estimated from Weissenberg films. In comparison with the previous refinement, the current redetermination reveals anisotropic displacement parameters for all non-H atoms, localization of the H atoms, and higher precision of lattice parameters and interatomic distances. The complex features a distorted S6 octahedral coordination geometry for tin and a cis disposition of the monodentate dithiocarbamate ligands.

(S-2-(2-Pyrrolidinio-1H-benzimidazol-3-ium dichloride monohydrate

Directory of Open Access Journals (Sweden)

Dai Jing

2009-06-01

Full Text Available In the title compound, C11H15N32+·2Cl−·H2O, one N atom of the imidazole ring and the N atom of the pyrrolidine ring are protonated. The crystal structure is stabilized by aromatic π–π interactions between the benzene rings of neighbouring benzimidazole systems [centroid–centroid duistance = 3.712 (2 Å]. The crystal structure is further stabilized by intermolecular N—H...Cl, O—H...Cl and N—H...O hydrogen bonds.

Fluorinated Amine Stereotriads via Allene Amination.

Science.gov (United States)

Liu, Lu; Gerstner, Nels C; Oxtoby, Lucas J; Guzei, Ilia A; Schomaker, Jennifer M

2017-06-16

The incorporation of fluorine into organic scaffolds often improves the bioactivity of pharmaceutically relevant compounds. C-F/C-N/C-O stereotriad motifs are prevalent in antivirals, neuraminidase inhibitors, and modulators of androgen receptors, but are challenging to install. An oxidative allene amination strategy using Selectfluor rapidly delivers triply functionalized triads of the form C-F/C-N/C-O, exhibiting good scope and diastereoselectivity for all syn products. The resulting stereotriads are readily transformed into fluorinated pyrrolidines and protected α-, β-, and γ-amino acids.

A short synthesis and its application to the preparation of radio labelled leukotriene inhibitor Sch 37224

International Nuclear Information System (INIS)

Duelfer, T.; Gala, D.

1991-01-01

A new, short synthesis of 1-(1,2-dihydro-4-hydroxyl-1-phenyl-2-oxo-1,8-naphthyridin-3-yl)-pyrrolidinium hydroxide, inner salt, 1, was achieved by condensing methyl 2-phenylamino-3-pyridine carboxylate 2 with ethyl 1-pyrrolidine acetate 4. This gave highly pure product in 60% yield. This synthesis was applied to the preparation of 14 C labelled 1. Radiolabelled 1 was synthesized from u-[ 14 C]-aniline in three steps at 97% radiochemical purity and 27.3% radiochemical yield. (author)

Facile synthesis of some novel 2-substituted-4,6-diarylpyrimidines using 4 ' -hydroxy-3 ' ,5 ' -dinitrochalcones and S-benzylthiouronium chloride

Directory of Open Access Journals (Sweden)

K. L. Ameta

2012-01-01

Full Text Available Various 4'-hydroxy-3',5'-dinitro substituted chalcones 1 and S-benzylthiouronium chloride (SBT 2 in the presence of DMF-organic bases (morpholine/ pyrrolidine/ piperidine gave 4,6-diaryl-2-(4-morpholinyl / 1-pyrrolidinyl /1-piperidinyl- pyrimidines 4, 5 and 6 in a facile one-pot conversion. In an another attempt reactants 1 and 2 yielded intermediate 2-benzylthiopyrimidines 3, in presence of DMF, which on treatment with heterocyclic secondary amines gave products 4, 5 and 6 in an alternate two-step process.

Spectroscopic studies on the interactions of 5-ethyl-6-phenyl-3,8-bis((3-aminoalkyl)propanamido)phenanthridin-5-ium derivatives with G-quadruplex DNA

Science.gov (United States)

Yalçın, Ergin; Duyar, Halil; Ihmels, Heiko; Seferoğlu, Zeynel

2018-05-01

An improved microwave-induced synthesis of five ethidium derivatives (Ethidium derivatives, 2a-d) is presented. As the derivatives 2a-d have been proposed previously to be telomerase inhibitors, the binding interactions of these ethidium derivatives with G-quadruplex DNA were evaluated by means of photometric and fluorimetric titration, thermal DNA denaturation, CD and 1H NMR spectroscopy. In particular, the compound bearing 3,8-bis(pyrrolidin-1-yl)propanamido substituent 2a exhibits high selectivity for G-quadruplex DNA relative to duplex DNA.

13-Hydroxy-4,16-dimethyl-4,16-diazapentacyclo[12.3.1.01,5.05,13.07,12]octadeca-7(12,8,10-triene-6,18-dione

Directory of Open Access Journals (Sweden)

K. Gurunathan

2009-05-01

Full Text Available In the title compound, C18H20N2O3, the N-methylpiperidone ring adopts a chair conformation. The pyrrolidine ring and the five-membered cyclopentane rings adopt envelope conformations. The five-membered ring of the ninhydrin system adopts an envelope conformation with the central C atom deviating by 0.217 (1Å from the mean plane through the other atoms. The molecular packing is characterized by intermolecular C—H...O and intramolecular C—H...O and O—H...N interactions.

Interaction of serum amyloid P component with hexanoyl bis(d-proline) (CPHPC)

Energy Technology Data Exchange (ETDEWEB)

Kolstoe, Simon E. [University College London, Rowland Hill Street, London NW3 2PF (United Kingdom); Jenvey, Michelle C. [University of Southampton, Southampton SO17 1BJ (United Kingdom); Purvis, Alan [Imperial College London, London SW7 2AZ (United Kingdom); Light, Mark E. [University of Southampton, Southampton SO17 1BJ (United Kingdom); Thompson, Darren [University of Sussex, Falmer, Brighton BN1 9RQ (United Kingdom); Hughes, Peter; Pepys, Mark B.; Wood, Stephen P., E-mail: s.wood@ucl.ac.uk [University College London, Rowland Hill Street, London NW3 2PF (United Kingdom)

2014-08-01

Serum amyloid P component is a pentameric plasma glycoprotein that recognizes and binds to amyloid fibres in a calcium-dependent fashion and is likely to contribute to their deposition and persistence in vivo. Five molecules of the drug CPHPC avidly cross-link pairs of protein pentamers and the decameric complex is rapidly cleared in vivo. Crystal structures of the protein in complex with a bivalent drug and cadmium ions, which improve crystal quality, allow the definition of the preferred bound drug isomers. Under physiological conditions, the pentameric human plasma protein serum amyloid P component (SAP) binds hexanoyl bis(d-proline) (R-1-(6-[R-2-carboxy-pyrrolidin-1-yl]-6-oxo-hexanoyl) pyrrolidine-2-carboxylic acid; CPHPC) through its d-proline head groups in a calcium-dependent interaction. Cooperative effects in binding lead to a substantial enhancement of affinity. Five molecules of the bivalent ligand cross-link and stabilize pairs of SAP molecules, forming a decameric complex that is rapidly cleared from the circulation by the liver. Here, it is reported that X-ray analysis of the SAP complex with CPHPC and cadmium ions provides higher resolution detail of the interaction than is observed with calcium ions. Conformational isomers of CPHPC observed in solution by HPLC and by X-ray analysis are compared with the protein-bound form. These are discussed in relation to the development of CPHPC to provide SAP depletion for the treatment of amyloidosis and other indications.

Stabilization of inorganic mixed waste to pass the TCLP and STLC tests using clay and pH-insensitive additives

International Nuclear Information System (INIS)

Bowers, J.S.; Anson, J.R.; Painter, S.M.; Maitino, R.E.

1995-03-01

Stabilization traps toxic contaminants (usually both chemically and physically) in a matrix so that they do not leach into the environment. Typical contaminants are metals (mostly transition metals) that exhibit the characteristic of toxicity. The stabilization process routinely uses pozzolanic materials. Portland cement, fly ash-lime mixes, gypsum cements, and clays are some of the most common materials. In many instances, materials that can pass the Toxicity Characteristic Leaching Procedure (TCLP-the federal leach test) or the Soluble Threshold Leachate Concentration (STLC-the California leach test) must have high concentrations of lime or other caustic material because of the low pH of the leaching media. Both leaching media, California's and EPA's, have a pH of 5.0. California uses citric acid and sodium citrate while EPA uses acetic acid and sodium acetate. These media can form ligands that provide excellent metal leaching. Because of the aggressive nature of the leaching medium, stabilized wastes in many cases will not pass the leaching tests. At the Lawrence Livermore National Laboratory, additives such as dithiocarbamates and thiocarbonates, which are pH-insensitive and provide resistance to ligand formation, are used in the waste stabilization process. Attapulgite, montmorillonite, and sepiolite clays are used because they are forgiving (recipe can be adjusted before the matrix hardens). The most frequently used stabilization process consists of a customized recipe involving waste sludge, clay and dithiocarbamate salt, mixed with a double planetary mixer into a pasty consistency. TCLP and STLC data on this waste matrix have shown that the process matrix meets land disposal requirements

Reactivities of some thiol collectors and their interactions with Ag (+1) ion by molecular modeling

Energy Technology Data Exchange (ETDEWEB)

Yekeler, Hulya; Yekeler, Meftuni

2004-09-15

The most commonly used collectors for sulfide minerals in the mining industry are the thiol collectors for the recovery of these minerals from their associated gangues by froth flotation. For this reason, a great deal of attention has been paid to understand the attachment mechanism of thiol collectors to metal sulfide surfaces. The density functional theory (DFT) calculations at the B3LYP/3-21G* and B3LYP/6-31++G** levels were employed to propose the flotation responses of these thiol collectors, namely, diethyl dithiocarbamate, ethyl dithiocarbamate, ethyl dithiocarbonate, ethyl trithiocarbonate and ethyl dithiophosphate ions, and to study the interaction energies of these collectors with Ag (+1) ion in connection to acanthite (Ag{sub 2}S) mineral. The calculated interaction energies, {delta}E, were interpreted in terms of the highest occupied molecular orbital (HOMO) energies of the isolated collector ions. The results show that the HOMOs are strongly localized to the sulfur atoms and the HOMO energies can be used as a reactivity descriptor for the flotation ability of the thiol collectors. Using the HOMO and {delta}E energies, the reactivity order of the collectors is found to be (C{sub 2}H{sub 5}){sub 2}NCS{sub 2}{sup -} > C{sub 2}H{sub 5}NHCS{sub 2}{sup -} > C{sub 2}H{sub 5}OCS{sub 2}{sup -} > C{sub 2}H{sub 5}SCS{sub 2}{sup -} > (C{sub 2}H{sub 5}O)(OH)PS{sub 2}{sup -}. The theoretically obtained results are in good agreement with the experimental data reported.

Estimation of modern range of fungicides and scope of their application in agriculture of Ukraine as component of state social and hygienic monitoring

Directory of Open Access Journals (Sweden)

Vavrinevych O.P.

2013-12-01

Full Text Available The analysis of the range of pesticides, including fungicides, authorized for use in Ukraine and the scope of their application during 1999 - 2012 years was carried out. Statistical research methods were used in the analysis, evaluation of the results was car¬ried out in terms of the rate of growth and increase. It was determined that in the range structure of pesticides, authorized for use in Ukraine the largest share accounted for herbicides. Part of the herbicides was 43,8±0,95% on average over the period from 1999 to 2012. The share of fungicides was 28,6±1,1%, insecticides - 20,3±0,78%, plant growth regulators - 7,4±0,59%. Mixed fungicides are the largest part of fungicides in the structure of the range (26,3-39,3%, the number of its had increased by 542% over 13-year period. Prior to 2003 there was a slight increase in the number of mixed fungicides, growth rate was 0-8,3% since 2006, its rate of increase has averaged 53% every 2 years. Triazoles and conazoles (14,9-31,4%, benzimidazoles, imidazoles (9,8-14,7%, carbamates, dithiocarbamates (3,1-13,8%, inorganic compounds (6,1-11,1% containing one active ingredient in formulation were the most common among the fungicides. The growth rate of strobilurin fungicides was 900%, triazoles – 550%, benzimidazoles, imidazoles – 400%, inorganic compounds – 243%, aniline-pyrimidines – 200%, pyrimidines, pyridines, pyrroles – 67%, dithiocarbamic and carbamic acid derivatives – 50%, phthalimides, phenylsulfamides, amides – 43%.

Crystal structure of bis-[N-(2-hy-droxy-eth-yl)-N-methyl-dithio-carbamato-κ2S,S'](pyridine)-zinc(II) pyridine monosolvate and its N-ethyl analogue.

Science.gov (United States)

Poplaukhin, Pavel; Tiekink, Edward R T

2017-07-01

The common structural feature of the title compounds, [Zn(C 4 H 8 NOS 2 ) 2 (C 5 H 5 N)]·C 5 H 5 N (I) and [Zn(C 5 H 10 NOS 2 ) 2 (C 5 H 5 N)]·C 5 H 5 N (II), which differ by having di-thio-carbamate N-bound methyl (I) and ethyl (II) groups, is the coordination of each Zn II atom by two non-symmetrically chelating di-thio-carbamate ligands and by a pyridine ligand; in each case, the non-coordinating pyridine mol-ecule is connected to the Zn-containing mol-ecule via a (hy-droxy)O-H⋯N(pyridine) hydrogen bond. The resulting NS 4 coordination geometry is closer to a square-pyramid than a trigonal bipyramid in the case of (I), but almost inter-mediate between the two extremes in (II). The mol-ecular packing features (hy-droxy)O-H⋯O(hy-droxy) hydrogen bonds, leading to supra-molecular chains with a zigzag arrangement along [10-1] (I) or a helical arrangement along [010] (II). In (I), π-π [inter-centroid distances = 3.4738 (10) and 3.4848 (10) Å] between coordinating and non-coordinating pyridine mol-ecules lead to stacks comprising alternating rings along the a axis. In (II), weaker π-π contacts occur between centrosymmetrically related pairs of coordinating pyridine mol-ecules [inter-centroid separation = 3.9815 (14) Å]. Further inter-actions, including C-H⋯π(chelate) inter-actions in (I), lead to a three-dimensional architecture in each case.

Technetium-99m dithiocarbamates: the development of a new hepatobiliary agent

International Nuclear Information System (INIS)

Baldas, J.; Pojer, P.M.

1983-01-01

Preparation of dithiocarbamato ligands, preparation of sup(99m)Tc-dithiocarbamato complexes and physical properties of these complexes are discussed. The in vivo distribution of the complexes in mice correlated with their polarity. The lipophilic complexes were rapidly extracted by the liver and were then either retained or were slowly excreted. The soluble, polar complexes were characterised by slow blood clearance which occurred concurrently with rapid liver excretion. The ethylenebis (dithiocarbamato) complex enabled gallbladder visualisation over a period greater than two and a half hours

Heteroleptic Palladium(II) dithiocarbamates: Synthesis, characterization and in vitro biological screening

Science.gov (United States)

Khan, Shahan Zeb; Zia-ur-Rehman; Amir, Muhammad Kashif; Ullah, Imdad; Akhter, M. S.; Bélanger-Gariepy, Francine

2018-03-01

Two new heteroleptic Pd(II) complexes of sodium 4-(2-pyrimidyl)piperazine-1-carbodithioate with tris-p-flourophenylphosphine (1) and tris-p-chlorophenylphosphine (2) were prepared and characterized by elemental analysis, FT-IR, multinuclear NMR {1H, 13C and 31P} and single-crystal X-ray diffraction measurement. In both complexes, Pd exhibit pseudo square planner geometry mediated by SS chelate, P and Cl. In vitro cytotoxicity against five different cancer cell lines using staurosporine as a standard revealed 1 to be more cytotoxic than 2, though both complexes are more active than cisplatin. Subsequent DNA binding studies revealed that non-covalent complex-DNA interaction may be the reason for arresting cancer cell growth. Furthermore, 1 and 2 are potent antioxidant agents.

Lewis acid catalyzed [3 + 2] annulation of ketenimines with donor-acceptor cyclopropanes: an approach to 2-alkylidenepyrrolidine derivatives.

Science.gov (United States)

Alajarin, Mateo; Egea, Adrian; Orenes, Raul-Angel; Vidal, Angel

2016-11-02

The [3 + 2] annulation reaction of C,C,N-trisubstituted ketenimines with donor-acceptor cyclopropanes bearing aryl, styryl and vinyl substituents at the C2 position, triggered by the Lewis acid Sc(OTf) 3 , supplies highly substituted pyrrolidines. Activated cyclopropanes fused to naphthalene and [1]benzopyrane nuclei are also suitable substrates in similar transformations, yielding partially saturated benz[g]indoles and [1]benzopyran[4,3-b]pyrroles. An intramolecular version of this ketenimine/cyclopropane [3 + 2] annulation has also been developed leading to the pyrrolo[2,1-a]isoindole framework.

Stereodivergent Synthesis of N-Heterocycles by Catalyst-Controlled, Activity-Directed Tandem Annulation of Diazo Compounds with Amino Alkynes.

Science.gov (United States)

Liu, Kai; Zhu, Chenghao; Min, Junxiang; Peng, Shiyong; Xu, Guangyang; Sun, Jiangtao

2015-10-26

A stereodivergent synthesis of five-membered N-heterocycles, such as 2,3-dihydropyrroles, and 2-methylene and 3-methylene pyrrolidines, has been developed through a tandem annulation of amino alkynes with diazo compounds and involves the trapping of in situ formed intermediates. Mechanistic investigations indicate that the copper-catalyzed tandem annulations proceed by allenoate formation and subsequent intramolecular hydroamination. In contrast, the rhodium-catalyzed protocol features a carbenoid insertion into the NH bond and subsequent Conia-ene cyclization. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nonanaplastic follicular cell-derived thyroid carcinoma

DEFF Research Database (Denmark)

Skansing, Daniel Bräuner; Londero, Stefano Christian; Asschenfeldt, Pia

2017-01-01

only on tumor necrosis and/or mitosis have a prognosis similar to those diagnosed according to the TURIN proposal. The purpose of this study was to evaluate prognosis for NAFCTC based on long-term follow-up illuminating the significance of tumor necrosis and mitosis. A cohort of 225 patients...... with NAFCTC was followed more than 20 years. Age, sex, distant metastasis, histology, tumor size, extrathyroidal invasion, lymph node metastasis, tumor necrosis and mitosis were examined as possible prognostic factors. Median follow-up time for patients alive was 28 years (range 20–43 years). Age, distant...... metastasis, extrathyroidal invasion, tumor size, tumor necrosis and mitosis were independent prognostic factors in multivariate analysis for overall survival (OS). In disease specific survival (DSS) age was not significant. Using only necrosis and/or mitosis as criteria for PDTC the 5-, 10- and 20-year OS...

Spectrophotometric determination of zinc in impure solutions; Determinacion Espectrofotometrica de Zinc en muestras de rio-Tinto prvia estracciond el Ditizonato con Tetracloruro

Energy Technology Data Exchange (ETDEWEB)

Rodriguez Hernandez, B; Reyes Tamaral, A

1972-07-01

A dithizone colorimetric method is described for determining zinc concentrations of 0.001 to 5 g/l in aqueous solutions from Rio Tinto Mines, containing copper, iron and other impurities. Citrate, cyanide and bis-(2hydroxyethyl)-dithiocarbamate are added to the aqueous sample of masking several metals, and zinc is extracted at pH 5 with a solution of dithizone in carbon tetrachloride. Excess of dithizone is removed with sodium sulphide, and optical density of zinc dithionate in organic solution is measured at 5.35 nm. Calibration curves obey Beer's law up to 0.5 micro Zn/ml. (Author) 5 refs.

Spectrophotometric determination of zinc in impure solutions

International Nuclear Information System (INIS)

Rodriguez Hernandez, B.; Reyes Tamaral, A.

1972-01-01

A dithizone colorimetric method is described for determining zinc concentrations of 0.001 to 5 g/l in aqueous solutions from Rio Tinto Mines, containing copper, iron and other impurities. Citrate, cyanide and bis-2hydroxyethyl)-dithiocarbamate are added to the aqueous sample of masking several metals, and zinc is extracted at pH 5 with a solution of dithizone in carbon tetrachloride. Excess of dithizone is removed with sodium sulphide, and optical density of zinc dithionate in organic solution is measured at 5.35 nm. Calibration curves obey Beer's law up to 0.5 micro Zn/ml. (Author) 5 refs

Spectrophotometric determination of zinc in impure solutions; Determinacion Espectrofotometrica de Zinc en muestras de rio-Tinto prvia estracciond el Ditizonato con Tetracloruro

Energy Technology Data Exchange (ETDEWEB)

Rodriguez Hernandez, B.; Reyes Tamaral, A.

1972-07-01

A dithizone colorimetric method is described for determining zinc concentrations of 0.001 to 5 g/l in aqueous solutions from Rio Tinto Mines, containing copper, iron and other impurities. Citrate, cyanide and bis-(2hydroxyethyl)-dithiocarbamate are added to the aqueous sample of masking several metals, and zinc is extracted at pH 5 with a solution of dithizone in carbon tetrachloride. Excess of dithizone is removed with sodium sulphide, and optical density of zinc dithionate in organic solution is measured at 5.35 nm. Calibration curves obey Beer's law up to 0.5 micro Zn/ml. (Author) 5 refs.

Standardization of solvent extraction procedure for determination of uranium in seawater

International Nuclear Information System (INIS)

Sukanta Maity; Sahu, S.K.; Pandit, G.G.

2015-01-01

Solvent extraction procedure using ammonium pyrolidine dithiocarbamate complexing agent in methyl isobutyl ketone organic phase and acid exchange back-extraction is described for the simultaneous quantitative pre-concentration of uranium in seawater followed by its determination by differential pulse adsorptive stripping voltammetry. Solvent extraction time is optimized for extraction of uranium from seawater. Solvent extraction efficiency for uranium in seawater at different pH was carried out. The method gives a recovery of 98 ± 2 % for 400 mL sample at pH 3.0 ± 0.02, facilitating the rapid and interference free analysis of seawater samples. (author)

Study of effects of engine oil additives on the properties of fluorelastomers; Fusso gomu ni oyobosu engine yu tenkazai no eikyo chosa

Energy Technology Data Exchange (ETDEWEB)

Kurono, K; Owaki, M; Suzuki, Y; Akiyama, K; Shionoya, M [Toyota Motor Corp., Aichi (Japan)

1997-10-01

Fluoroelastmers are well known for their resistance to heat and fluids and have become major material for crankcase oil sealers. On the other hand new additive formulations are developed for engine lubricants used for fuel economic gasoline engines. In this paper the effects of those additives on properties of fluoroelastmers are investigated. The results of the immersion tests of both test plaques and oil sealer products indicates that dithiocarbamates friction modifier have hardening effects on fluoroelastomers. The fluoroelastmer deterioration mechanism is presumed by analysis of elastmer samples after immersion in oil. 6 refs., 9 figs., 3 tabs.

2-[4-(2-Chloroacetylphenyl]-2-methyl-1-(pyrrolidin-1-ylpropan-1-one

Directory of Open Access Journals (Sweden)

Dong-mei Ren

2013-08-01

Full Text Available The asymmetric unit of the title compound, C16H20ClNO2, contains two molecules in which the dihedral angles between the benzene ring and the plane of the amide unit are 77.4 (1 and 81.1 (1°. In both molecules, the five-membered ring adopts an envelope conformation with one of the β-C atoms as the flap. In the crystal, molecules are connected via C—H...O hydrogen bonds, forming chains along the b-axis direction. These chains are further linked by C—H...π interactions, forming a three-dimensional network.

A novel surfactant S-benzoyl-N,N-diethyldithiocarbamate synthesis and its flotation performance to galena

Energy Technology Data Exchange (ETDEWEB)

Ma, Xin; Hu, Yuan; Zhong, Hong, E-mail: zhongh@csu.edu.cn; Wang, Shuai, E-mail: wangshuai@csu.edu.cn; Liu, Guangyi; Zhao, Gang

2016-03-01

Graphical abstract: - Highlights: • A novel surfactant BEDTC was first introduced as galena flotation collector. • BEDTC exhibited superior collecting power to galena against sphalerite. • BEDTC has two active centers to mineral surfaces. • BEDTC molecules formed two distinct adsorption geometries on galena surfaces. - Abstract: In this paper, a novel dithiocarbamate compound, S-benzoyl-N,N-diethyldithiocarbamate (BEDTC), was synthesized via one-pot reaction of diethylamine, carbon disulfide, sodium hydroxide and benzoyl chloride using abundant carbon disulfide as a solvent. Its flotation performance and adsorption mechanism on the galena was first investigated by flotation tests, adsorption quantity measurements, FTIR spectra, X-ray photoelectron spectra (XPS) and density functional theory (DFT) calculation. The flotation results illustrated that BEDTC exhibited stronger collecting power than the conventional sulphide collectors such as sodium diethyl dithiocarbamate (SEDTC) and sodium isobutyl xanthate (SIBX) and superior selectivity for galena against sphalerite. The adsorption data demonstrated that the adsorption affinity of BEDTC to galena was stronger than that of SEDTC and SIBX, and the preferable pH range for BEDTC adsorption on galena surfaces was 6–10. The results of FTIR spectra and XPS indicated that the interaction of BEDTC with galena may be dominated by the chemical adsorption, which was further confirmed by DFT calculation. BEDTC probably acted as a bidentate ligand, bonding with lead through the thiol sulfur and carbonyl oxygen atoms to form two distinct adsorption geometries, one with the same Pb atom to form a six-membered ring complex, and the other with two different Pb atoms to form a ''bullet'' shape complex.

Discovery of a potent, dual serotonin and norepinephrine reuptake inhibitor.

Science.gov (United States)

Dreyfus, Nicolas; Myers, Jason K; Badescu, Valentina O; de Frutos, Oscar; de la Puente, Maria Luz; Ding, Chunjin; Filla, Sandra A; Fynboe, Karsten; Gernert, Douglas L; Heinz, Beverly A; Hemrick-Luecke, Susan K; Johnson, Kirk W; Johnson, Michael P; López, Pilar; Love, Patrick L; Martin, Laura J; Masquelin, Thierry; McCoy, Michael J; Mendiola, Javier; Morrow, Denise; Muhlhauser, Mark; Pascual, Gustavo; Perun, Thomas J; Pfeifer, Lance A; Phebus, Lee A; Richards, Simon J; Rincón, Juan Antonio; Seest, Eric P; Shah, Jikesh; Shaojuan, Jia; Simmons, Rosa Maria A; Stephenson, Gregory A; Tromiczak, Eric G; Thompson, Linda K; Walter, Magnus W; Weber, Wayne W; Zarrinmayeh, Hamideh; Thomas, Craig E; Joshi, Elizabeth; Iyengar, Smriti; Johansson, Anette M

2013-06-13

The objective of the described research effort was to identify a novel serotonin and norepinephrine reuptake inhibitor (SNRI) with improved norepinephrine transporter activity and acceptable metabolic stability and exhibiting minimal drug-drug interaction. We describe herein the discovery of a series of 3-substituted pyrrolidines, exemplified by compound 1. Compound 1 is a selective SNRI in vitro and in vivo, has favorable ADME properties, and retains inhibitory activity in the formalin model of pain behavior. Compound 1 thus represents a potential new probe to explore utility of SNRIs in central nervous system disorders, including chronic pain conditions.

Opportunities and challenges for direct C–H functionalization of piperazines

Directory of Open Access Journals (Sweden)

Zhishi Ye

2016-04-01

Full Text Available Piperazine ranks within the top three most utilized N-heterocyclic moieties in FDA-approved small-molecule pharmaceuticals. Herein we summarize the current synthetic methods available to perform C–H functionalization on piperazines in order to lend structural diversity to this privileged drug scaffold. Multiple approaches such as those involving α-lithiation trapping, transition-metal-catalyzed α-C–H functionalizations, and photoredox catalysis are discussed. We also highlight the difficulties experienced when successful methods for α-C–H functionalization of acyclic amines and saturated mono-nitrogen heterocyclic compounds (such as piperidines and pyrrolidines were applied to piperazine substrates.

4-Hydroxy-5-(4-methoxyphenylpyrrolidin-2-one

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Suchada Chantrapromma

2008-03-01

Full Text Available In the title compound, C11H13NO3, the pyrrolidin-2-one ring is in an envelope conformation with the hydroxyl and 4-methoxyphenyl substituents mutually cis. The methoxy group is slighty twisted away from the mean plane of the attached benzene ring. The molecules are arranged into screw chains along the c axis. These chains are interconnected via intermolecular O—H...O and N—H...O hydrogen bonds into sheets parallel to the ac plane. The crystal structure is further stabilized by weak intermolecular C—H...O and C—H...π interactions.

Rhodium-Catalyzed Denitrogenative [3+2] Cycloaddition: Access to Functionalized Hydroindolones and the Framework of Montanine-Type Amaryllidaceae Alkaloids.

Science.gov (United States)

Yang, Hongjian; Hou, Shengtai; Tao, Cheng; Liu, Zhao; Wang, Chao; Cheng, Bin; Li, Yun; Zhai, Hongbin

2017-09-18

Rhodium-catalyzed denitrogenative [3+2] cycloaddition of 1-sulfonyl-1,2,3-triazoles with cyclic silyl dienol ethers has been developed for the synthesis of functionalized hydroindolones or their corresponding silyl ethers. The present method has been employed to construct synthetically valuable bicyclo[3.3.1]alkenone derivatives and pyrrolidine-ring-containing bicyclic indole compounds. As a further synthetic application, a stereoselective synthesis of 5,11-methanomorphanthridin-3-one, which shares a key skeleton with montanine-type Amaryllidaceae alkaloids has been achieved by using this chemistry. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

New enamine derivatives of lapachol and biological activity

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OLIVEIRA MAILCAR F.

2002-01-01

Full Text Available A convenient synthesis of the new enamine derivatives 2-(4-morpholinyl-3-(3-methyl-2-butenyl-1,4-naphthalenedione, 2-(1-piperidinyl-3-(3-methyl-2-butenyl-1,4-naphtalenedione and 2-(1-pyrrolidinyl-3-(3-methyl-2-butenyl-1,4-naphthalenedione was carried out from natural 2-hydroxy-3-(3-methyl-2-butenyl-1,4-naphthalenedione (lapachol and morpholine, piperidine and pyrrolidine. The structures of the products were established mainly by NMR analysis, including 2D experiments. Biological activities of these products were evaluated against Artemia salina, Aedes aegypti and cytotoxicity using A549 human breast cells.

Discovery and Optimization of Imidazopyridine-Based Inhibitors of Diacylglycerol Acyltransferase 2 (DGAT2).

Science.gov (United States)

Futatsugi, Kentaro; Kung, Daniel W; Orr, Suvi T M; Cabral, Shawn; Hepworth, David; Aspnes, Gary; Bader, Scott; Bian, Jianwei; Boehm, Markus; Carpino, Philip A; Coffey, Steven B; Dowling, Matthew S; Herr, Michael; Jiao, Wenhua; Lavergne, Sophie Y; Li, Qifang; Clark, Ronald W; Erion, Derek M; Kou, Kou; Lee, Kyuha; Pabst, Brandon A; Perez, Sylvie M; Purkal, Julie; Jorgensen, Csilla C; Goosen, Theunis C; Gosset, James R; Niosi, Mark; Pettersen, John C; Pfefferkorn, Jeffrey A; Ahn, Kay; Goodwin, Bryan

2015-09-24

The medicinal chemistry and preclinical biology of imidazopyridine-based inhibitors of diacylglycerol acyltransferase 2 (DGAT2) is described. A screening hit 1 with low lipophilic efficiency (LipE) was optimized through two key structural modifications: (1) identification of the pyrrolidine amide group for a significant LipE improvement, and (2) insertion of a sp(3)-hybridized carbon center in the core of the molecule for simultaneous improvement of N-glucuronidation metabolic liability and off-target pharmacology. The preclinical candidate 9 (PF-06424439) demonstrated excellent ADMET properties and decreased circulating and hepatic lipids when orally administered to dyslipidemic rodent models.

The Influence of pH and Temperature on the Stability of N-[(Piperidinemethylene]daunorubicin Hydrochloride and a Comparison of the Stability of Daunorubicin and Its Four New Amidine Derivatives in Aqueous Solutions

Directory of Open Access Journals (Sweden)

Mikołaj Piekarski

2014-01-01

Full Text Available The influence of pH and temperature on the stability of N-[(piperidinemethylene]daunorubicin hydrochloride (PPD was investigated. Degradation was studied using an HPLC method. Specific acid-base catalysis of PPD involves hydrolysis of protonated molecules of PPD catalyzed by hydrogen ions and spontaneous hydrolysis under the influence of water zwitterions, unprotonated molecules, and monoanions of PPD. The thermodynamic parameters of these reactions, energy, enthalpy, and entropy, were calculated. Also, the stability of daunorubicin and its new amidine derivatives (piperidine, morpholine, pyrrolidine, and hexahydroazepin-1-yl in aqueous solutions was compared and discussed.

Towards the chiral metabolomics: Liquid chromatography–mass spectrometry based DL-amino acid analysis after labeling with a new chiral reagent, (S)-2,5-dioxopyrrolidin-1-yl-1-(4,6-dimethoxy-1,3,5-triazin-2-yl) pyrrolidine-2-carboxylate, and the application to saliva of healthy volunteers

Energy Technology Data Exchange (ETDEWEB)

Mochizuki, Toshiki; Takayama, Takahiro; Todoroki, Kenichiro; Inoue, Koichi; Min, Jun Zhe; Toyo’oka, Toshimasa, E-mail: toyooka@u-shizuoka-ken.ac.jp

2015-05-22

Highlights: • A novel chiral labeling reagent was synthesized. • Analysis of DL-amino acids was performed by UPLC–ESI-MS/MS. • Efficient enantioseparation and detection of DL-amino acids were performed. • DL-Amino acid in saliva was successfully determined under mild conditions. - Abstract: A novel triazine-type chiral derivatization reagent, i.e., (S)-2,5-dioxopyrrolidin-1-yl-1-(4,6-dimethoxy-1,3,5-triazin-2-yl) pyrrolidine-2-carboxylate (DMT-(S)-Pro-OSu), was developed for the highly sensitive and selective detection of chiral amines and amino acids by UPLC–MS/MS analysis. The enantiomers of amino acids were easily labeled with the reagents at room temperature within 40 min in an alkaline medium containing triethylamine. The diastereomers derived from proteolytic amino acids, except serine, were well separated under isocratic elution conditions by reversed-phase chromatography using an ODS column (R{sub s} = 1.2–9.0). DL-Serine was separated by use of an ADME column which has relatively higher polar surface than the conventional ODS column. The characteristic product ions, i.e., m/z 195.3 and m/z 209.3, were detected from all the diastereomers by the collision-induced dissociation of the protonated molecule. A highly sensitive detection on the amol–fmol level was obtained from the selected reaction monitoring (SRM) chromatogram. The chiral amines (e.g., adrenaline and noradrenaline) labeled with DMT-(S)-Pro-OSu were also well separated and sensitively detected by the present procedure. The method using DMT-(S)-Pro-OSu was used for the determination of DL-amino acids in the human saliva from healthy volunteers. Various L-amino acids were identified in the saliva. Furthermore, D-alanine (D-Ala) and D-proline (D-Pro) were also detected in relatively high concentrations (>5%). The ratio was higher in male saliva than in female saliva. However, the difference in the ratio of D-Ala for one day was not very high and the effect of foods and beverage

Determination of platinum and gold in biological materials by neutron activation analysis

International Nuclear Information System (INIS)

Taskaev, E.; Grigorov, T.

1988-01-01

A procedure for platinum and gold determination utilizing neutron activation combined with radiochemical separation was developed. The reaction 198 Pt (n, γ) 199 Pt undergoing β decay into 199 Au is used for Pt determination. Four procedures for gold separation are examined: adsorption on untreated polyurethane foam (UPF), extraction with dibutyl sulphide, reduction of gold to elementary state in conc. H 2 SO 4 , and extraction of gold as diethyl-dithiocarbamate complex. The extraction with Cu(DDC) 2 is chosen as the most suitable process and applied to platinum and gold determinations in Bowen's Kale and mice organs, previously treated with Biocisplatinum specimens. (author) 12 refs.; 5 figs

Synthesis of tetramethylthiuram disulfide ({sup 35}S); Synthese du disulfure de tetramethylthiurame ({sup 35}S)

Energy Technology Data Exchange (ETDEWEB)

Bentov, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

Tetramethylthiuram disulfide ({sup 35}S) has been prepared by exchange between elementary sulfur ({sup 35}S) and sodium N-dithiocarbamate followed by an oxidation with potassium ferricyanide. The method allows to obtain rapidly a pure product with relatively high activity. The radioactive exchange is 82 per cent. (author) [French] Le disurfure de tetramethylthiurame ({sup 35}S) a ete prepare par echange entre le soufre elementaire ({sup 35}S) et le N-dimethyldithiocarbamate de soude suivi d'une oxydation par le ferricyanure de potasse. La methode permet d'obtenir rapidement un produit pur avec une activite relativement haute. L'echange radioactif effectue est de 82 pour cent. (auteur)

Search for new potential anticonvulsants with anxiolytic and antidepressant properties among derivatives of 4,4-diphenylpyrrolidin-2-one.

Science.gov (United States)

Malawska, Katarzyna; Rak, Aleksandra; Gryzło, Beata; Sałat, Kinga; Michałowska, Małgorzata; Żmudzka, Elżbieta; Lodarski, Krzysztof; Malawska, Barbara; Kulig, Katarzyna

2017-02-01

The aim of this study was to synthesize a series of new N-Mannich bases derived from 4,4-diphenylpyrrolidin-2-one having differently substituted 4-phenylpiperazines as potential anticonvulsant agents with additional (beneficial) pharmacological properties. The target compounds 8-12 were prepared in one step from the 4-substituted phenylpiperazines, paraformaldehyde, and synthesized 4,4-diphenylpyrrolodin-2-one (7) by a Mannich-type reaction. The obtained compounds were assessed and tested for their anticonvulsant activity in two screening mouse models of seizures, i.e., the maximal electroshock (MES) test and in the subcutaneous pentylenetetrazole (scPTZ) test. The effect of these compounds on animals' motor coordination was measured in the rotarod test. A selected 4,4-diphenyl-1-((4-phenylpiperazin-1-yl)methyl)pyrrolidin-2-one (8) was evaluated in vivo for its anxiolytic- and antidepressant-like properties. Its impact on animals' locomotor activity was also evaluated. Compound 8 showed protection (25%) in the MES and in the scPTZ tests at the dose of 100mg/kg and was not neurotoxic. In the four-plate test, compound 8 at the dose of 30mg/kg showed a statistically significant (p<0.05) anxiolytic-like activity. In the forced swim test, it reduced the immobility time by 24.3% (significant at p<0.05), which indicates its potential antidepressant-like properties. In the locomotor activity test, compound 8 significantly reduced animals' locomotor activity by 79.9%. The results obtained make a new derivative of 4,4-diphenyl-1-((4-phenylpiperazin-1-yl)methyl)pyrrolidin-2-one (8) a promising lead structure for further development. Copyright © 2016. Published by Elsevier Urban & Partner Sp. z o.o.

Nanostructured interfaces with site-specific bioreceptors for immunosensing

Energy Technology Data Exchange (ETDEWEB)

Paiva, Telmo O.; Almeida, Inês; Marquês, Joaquim T. [Centro de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, Edifício C8, 1749-016 Lisboa (Portugal); Liu, Wei [NML, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100190 (China); Institute of Microelectronics, Tsinghua University, Beijing 100084 (China); Niu, Yu [NML, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100190 (China); Jin, Gang, E-mail: gajin@imech.ac.cn [NML, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100190 (China); School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049 (China); Viana, Ana S., E-mail: anaviana@fc.ul.pt [Centro de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, Edifício C8, 1749-016 Lisboa (Portugal)

2017-08-01

Highlights: • Innovative and simple strategy to create sensitive immunosensing platforms. • Gold surface modification with dithiocarbamate nanoconjugates of protein A. • CS{sub 2} strongly adsorbed on gold able to block protein nonspecific adsorption. • High performance for antigen detection by properly oriented antibodies. - Abstract: In this work, we propose a simple and effective approach to build nanostructured immunosensor platforms. The one-step strategy relies on i) the in situ formation of dithiocarbamates from the reaction between carbon disulfide and amine groups, present on protein A, ii) their attachment to gold nanoparticles (AuNPs), and iii) the linkage of the modified AuNPs to the electrode surface, which depends on the strong interaction between gold substrates and sulfur moieties. AuNPs and protein A are used to increase the surface coverage of Immunoglobulin G (IgG) and promote the oriented immobilization of the antibodies on the immunosensing interface. The modified gold surfaces with biomolecules were thoroughly characterized by a combination of techniques: UV–vis spectrophotometry, conventional ellipsometry and atomic force microscopy. The immunosensor performance was assessed in real-time, by surface plasmon resonance and by the highly sensitive total internal reflection imaging ellipsometry, through the specific biorecognition between anti-IgG and the immobilized IgG molecules. We demonstrate that the presence of AuNPs improves the sensitivity of the anti-IgG specific detection, whereas the presence of co-adsorbed CS{sub 2} is responsible for blocking the undesired protein nonspecific adsorption to the gold substrate. Overall, we report a simple and innovative one-step method, to chemically modify gold surfaces with protein A and AuNPs, able to specifically detect antigen/antibody interactions with capability of preventing protein nonspecific adsorption.

Stabilization of inorganic mixed waste to pass the TCLP and STLC tests using clay and pH-insensitive additives

Energy Technology Data Exchange (ETDEWEB)

Bowers, J.S.; Anson, J.R.; Painter, S.M. [Lawrence Livermore National Lab., CA (United States)] [and others

1995-12-31

Stabilization is a best demonstrated available technology, or BDAT. This technology traps toxic contaminants in a matrix so that they do not leach into the environment. The stabilization process routinely uses pozzolanic materials. Portland cement, fly ash-lime mixes, gypsum cements, and clays are some of the most common materials. In many instances, materials that can pass the Toxicity Characteristic Leaching Procedure (TCLP the federal leach test) or the Soluble Threshold Leachate Concentration (STLC the California leach test) must have high concentrations of lime or other caustic material because of the low pH of the leaching media. Both leaching media, California`s and EPA`s, have a pH of 5.0. California uses citric acid and sodium citrate while EPA uses acetic acid and sodium acetate. The concentration in the leachate is approximately ten times higher for the STLC procedure than the TCLP. These media can form ligands that provide excellent metal leaching. Because of the aggressive nature of the leaching medium, stabilized wastes in many cases will not pass the leaching tests. At the Lawrence Livermore National Laboratory (LLNL), additives such as dithiocarbamates and thiocarbonates, which are pH-insensitive and provide resistance to ligand formation, are used in the waste stabilization process. Attapulgite, montmorillonite, and sepiolite clays are used because they are forgiving (recipe can be adjusted before the matrix hardens) when formulating a stabilization matrix, and they have a neutral pH. By using these clays and additives, LLNL`s highly concentrated wastewater treatment sludges have passed the TCLP and STLC tests. The most frequently used stabilization process consists of a customized recipe involving waste sludge, clay and dithiocarbamate salt, mixed with a double planetary mixer into a pasty consistency. TCLP and STLC data on this waste matrix have shown that the process matrix meets land disposal requirements.

Cu(I)/Cu(II) mixed-valence surface complexes of S-[(2-hydroxyamino)-2-oxoethyl]-N,N-dibutyldithiocarbamate: Hydrophobic mechanism to malachite flotation.

Science.gov (United States)

Liu, Sheng; Zhong, Hong; Liu, Guangyi; Xu, Zhenghe

2018-02-15

Hydroxamate and sulfhydryl surfactants are effective collectors for flotation of copper minerals. The combination application of hydroxamate and sulfhydryl collectors has been proved to be an effective approach for improving the flotation recovery of non-sulfide copper minerals. A surfactant owing both hydroxamate and dithiocarbamate groups might exhibit strong affinity to non-sulfide copper minerals through double sites adsorption, rendering an enhanced hydrophobization to non-sulfide copper minerals flotation. The flotation performance of S-[(2-hydroxyamino)-2-oxoethyl]- N,N-dibutyldithiocarbamate (HABTC) to malachite, calcite and quartz were first evaluated through systematic micro-flotation experiments. HABTC's hydrophobic mechanism to malachite was further investigated and analyzed by zeta potential, Fourier transform infrared spectroscopy (FTIR), time-of-flight secondary ion mass spectrometry (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS). The micro-flotation results demonstrated HABTC was an excellent collector for malachite flotation and exhibited favorable selectivity for flotation separation of malachite from quartz or calcite under pH 8.5-10.3. Zeta potential and FTIR implied that HABTC might bond with the surface copper atoms of malachite, with releasing the H + ions of its hydroxamate group into pulp. ToF-SIMS provided clear evidences that the Cu-hydroxamate and Cu-dithiocarbamate groups were formed on malachite surfaces after HABTC adsorption. XPS revealed that Cu(I)/Cu(II) mixed-valence surface complexes of HABTC anchored on malachite through formation of Cu(I)S and Cu(II)O bonds, accompanying with reduction of partial surface Cu(II) to Cu(I). The Cu(I)/Cu(II) mixed-valence double chelating character and "chair"-shape N,N-dibutyldithiocarbamate hydrophobic group, resulting in an enhanced affinity and hydrophobization of HABTC to malachite flotation. Copyright © 2017 Elsevier Inc. All rights reserved.

Asymmetric Michael Addition Mediated by Chiral Ionic Liquids.

Science.gov (United States)

Suzuki, Yumiko

2018-06-01

Chiral ionic liquids with a focus on their applications in asymmetric Michael additions and related reactions were reviewed. The examples were classified on the basis of the mode of asymmetric induction (e.g., external induction/non-covalent interaction or internal induction/covalent bond formation), the roles in reactions (as a solvent or catalyst), and their structural features (e.g., imidazolium-based chiral cations, other chiral oniums; proline derivatives). Most of the reactions with high chiral induction are Michael addition of ketones or aldehydes to chalcones or nitrostyrenes where proline-derived chiral ionic liquids catalyze the reaction through enamine/ iminium formation. Many reports demonstrate the recyclability of ionic liquid-tagged pyrrolidines.

Rhodium(III)-catalyzed [3+2] annulation of 5-aryl-2,3-dihydro-1H-pyrroles with internal alkynes through C(sp²)-H/alkene functionalization.

Science.gov (United States)

Zhou, Ming-Bo; Pi, Rui; Hu, Ming; Yang, Yuan; Song, Ren-Jie; Xia, Yuanzhi; Li, Jin-Heng

2014-10-13

This study describes a new rhodium(III)-catalyzed [3+2] annulation of 5-aryl-2,3-dihydro-1H-pyrroles with internal alkynes using a Cu(OAc)2 oxidant for building a spirocyclic ring system, which includes the functionalization of an aryl C(sp(2))-H bond and addition/protonolysis of an alkene C=C bond. This method is applicable to a wide range of 5-aryl-2,3-dihydro-1H-pyrroles and internal alkynes, and results in the assembly of the spiro[indene-1,2'-pyrrolidine] architectures in good yields with excellent regioselectivities. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

2-Hydroxy-16-[(E-4-methylbenzylidene]-13-(4-methylphenyl-12-phenyl-1,11-diazapentacyclo[12.3.1.02,10.03,8.010,14]octadeca-3(8,4,6-triene-9,15-dione

Directory of Open Access Journals (Sweden)

Raju Suresh Kumar

2010-08-01

Full Text Available In the title compound, C37H32N2O3, an intramolecular O—H...N hydrogen bond generates a five-membered ring, producing an S(5 motif. The piperidone ring adopts a half-chair conformation. The two fused pyrrolidine rings have similar envelope conformations. The interplanar angles between the benzene rings A/B and C/D are 75.68 (7 and 30.22 (6°, respectively. In the crystal structure, adjacent molecules are interconnected into chains propagating along the [010] direction via intermolecular C—H...O hydrogen bonds. Further stabilization is provided by weak C—H...π interactions.

[1+1+3] Annulation of Diazoenals and Vinyl Azides: Direct Synthesis of Functionalized 1-Pyrrolines through Olefination.

Science.gov (United States)

Kanchupalli, Vinaykumar; Katukojvala, Sreenivas

2018-05-04

A dirhodium carboxylate catalyzed [1+1+3] annulation reaction of diazoenals and vinyl azides that gives synthetically important enal-functionalized 1-pyrroline derivatives was developed. The reaction involves a novel rhodium-catalyzed olefination of diazoenals with vinyl azides via electrophilic enal carbenoids, resulting in a new class of enal acrylates. The annulation reaction was used for the direct synthesis of valuable deuterated 1-pyrrolines. Structural diversification of the enal-functionalized 1-pyrrolines resulted in the biologically important pyrrolidine-fused oxaziridine, amino acid derivatives, and a 6-azabicyclo[3.2.1]octane motif present in polycyclic alkaloids. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Survey of pesticide residues in table grapes: Determination of processing factors, intake and risk assessment

DEFF Research Database (Denmark)

Poulsen, Mette Erecius; Hansen, H.K.; Sloth, Jens Jørgen

2007-01-01

of the European Union maximum residue limit (MRL) were found in five samples from Italy. A number of samples were rinsed to study the possible reduction of residues. For copper, iprodione, procymidone and dithiocarbamates a significant effect of rinsing was found (20-49% reduction of residues). However......(-1) for pesticides and 21 mu g day(-1) for copper. Correspondingly, the intakes from South African grapes were 2.6 and 5.7 mu g day(-1) respectively. When the total exposure of pesticides from grapes were related to acceptable daily intake, expressed as the sum of Hazard Quotients, the exposure were...... approximately 0.5% for Italian samples and 1% for South African samples....

Effects of Forsythia suspensa on expression of NF-κB and Foxp3 during liver injury in rats with severe acute pancreatitis

Directory of Open Access Journals (Sweden)

FAN Xiaobin

2013-07-01

Full Text Available ObjectiveTo investigate the roles of nuclear factor-kappa B (NF-κB and forkhead box P3 (Foxp3 during liver injury in rats with severe acute pancreatitis (SAP and the effects of Forsythia suspensa on their expression. MethodsEighty male Wistar rats were randomly allocated into sham operation (SO group, SAP group, and intervention group. The intervention group was further divided into high-dose, middle-dose, and low-dose Forsythia suspensa subgroups and positive control (PDTC subgroup. A rat model was induced by injecting sodium taurocholate into the bile-pancreatic duct. The rats in SO and SAP groups were sacrificed at 3, 6, and 12 h after operation, and those in intervention group were sacrificed at 12 h after operation. The serum levels of amylase (Amy, alanine aminotransferase (ALT, and tumor necrosis factor (TNFα were measured. The endotoxin content in plasma was determined using a limulus reagent. The percentage of Treg cells among peripheral blood lymphocytes was measured by flow cytometry. The pathological examination and scoring of the liver and pancreas were performed. The mRNA expression levels of NF-κB and Foxp3 in liver tissue were measured by RT-PCR. One-way analysis of variance was used for comparison among groups; multiple comparison was performed by LSD test; the indices were subjected to linear correlation analysis. ResultsCompared with those in the SO group, all the indices in the SAP group increased over time and reached the peak levels at 12 h after operation. Compared with the rats in SAP group that were sacrificed at 12 h after operation, the intervention group (mortality = 0 had significantly decreased mRNA expression of NF-κB and Foxp3 in liver tissue (P＜0.01. The NF-κB mRNA level was positively correlated with the percentage of Treg cells (r=0.738, P＜0.01. As the dose of Forsythia suspensa rose, Amy, ALT, and TNFα levels decreased significantly, and the inflammation of liver and pancreas was significantly

Crystal structures of two triazola-dioxola-benzenacyclononaphanes

Directory of Open Access Journals (Sweden)

Vijayan Viswanathan

2015-07-01

Full Text Available In the title compounds, C25H29BrN5O7, (I [systematic name: (Z-15-bromo-32,32-dimethyl-21-nitro-22,23,25,26,27,27a,33a,35,36,36a-decahydro-21H,61H-4,9-dioxa-2(3,2-pyrrolizina-6(4,1-triazola-3(5,6-furo[2,3-d][1,3]dioxola-1(1,2-benzenacyclononaphane], and C24H29N5O7S, (II [systematic name: (Z-32,32-dimethyl-27-nitro-25,26,27,27a,33a,35,36,36a-octahydro-21H,23H,61H-4,9-dioxa-2(5,6-pyrrolo[1,2-c]thiazola-6(4,1-triazola-3(5,6-furo[2,3-d][1,3]dioxola-1(1,2-benzenacyclononaphane], the triazole rings adopt almost planar conformations. In (I, the fused pyrrolidine rings adopt envelope conformations with the C atoms opposite the fused N—C bond as the flap in each ring, and their mean planes are inclined to one another by 52.8 (3°. In (II, the pyrrolidine and thiazole rings are both twisted on the fused N—C bond, and their mean planes are inclined to one another by 70.8 (2°. In both (I and (II, the furan ring adopts an envelope conformation with the adjacent C atom of the macrocycle as the flap. In the crystal of (I, molecules are linked via C—H...N and C—H...O hydrogen bonds, forming sheets parallel to (10-1, while in (II, molecules are linked via C—H...N and C—H...O hydrogen bonds, forming helical chains propagating along [010], which are linked via C—H...S hydrogen bonds, forming slabs parallel to (001.

Asymmetric Michael Addition Mediated by Chiral Ionic Liquids

Science.gov (United States)

Suzuki, Yumiko

2018-01-01

Chiral ionic liquids with a focus on their applications in asymmetric Michael additions and related reactions were reviewed. The examples were classified on the basis of the mode of asymmetric induction (e.g., external induction/non-covalent interaction or internal induction/covalent bond formation), the roles in reactions (as a solvent or catalyst), and their structural features (e.g., imidazolium-based chiral cations, other chiral oniums; proline derivatives). Most of the reactions with high chiral induction are Michael addition of ketones or aldehydes to chalcones or nitrostyrenes where proline-derived chiral ionic liquids catalyze the reaction through enamine/ iminium formation. Many reports demonstrate the recyclability of ionic liquid-tagged pyrrolidines. PMID:29861702

Modification of indole by electron-rich atoms and their application in novel electron donor materials

Science.gov (United States)

Zhang, Maolin; Qin, Guangjiong; Liu, Jialei; Zhen, Zhen; Fedorchuk, A. A.; Lakshminarayana, G.; Albassam, A. A.; El-Naggar, A. M.; Ozga, Katarzyna; Kityk, I. V.

2017-08-01

Novel nonlinear optical (NLO) chromophore based on 6-(pyrrolidin-1-yl)-1H-indole as the electron donor group was designed and synthesized. The molecular structure of this chromophore was characterized by 1H NMR spectra, 13C NMR spectra, and MS spectra. The delocalized energy level was estimated by UV-Vis. spectra. The thermal property was studied by thermogravimetric analysis (TGA). The poled films containing chromophores ZML-1 with a loading density of 10 wt% in amorphous polycarbonate (APC) afford an average electro-optic (EO) coefficient (r33) of 19 pm/V at 1310 nm. Compared to the reported aniline-based chromophore (r33 = 12 pm/V) analogues, chromophore ZML-1 exhibits enhanced electro-optical activity.

Neutron spectroscopic and Raman studies of interaction between water and proline

Energy Technology Data Exchange (ETDEWEB)

Zhang Peng [Department of Space Science and Applied Physics, Shandong University at Weihai, Weihai 264209 (China); State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100080 (China); Han Shenghao [Department of Space Science and Applied Physics, Shandong University at Weihai, Weihai 264209 (China); Zhang Ying [State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100080 (China); Ford, Robert C. [MIB, University of Manchester, Manchester M60 1QD (United Kingdom); Li Jichen [Department of Physics and Astronomy, University of Manchester, Manchester M60 1QD (United Kingdom)], E-mail: j.c.li@manchester.ac.uk

2008-04-18

A series of measurements for the vibrational dynamics of water around proline were made by using inelastic neutron scattering and Raman spectroscopy techniques. Comparing the spectra at different hydrations, we found that proline has very different hydrophilic property compared with other amino acids we have studied [Y. Zhang et al., J. Phys. Chem. B 109 (2005) 17784]. We interpret these differences in terms of the unique structure of proline with an imino group which is fixed rigidly in the pyrrolidine ring. As result, we may observe a non-ionic form of proline solid transformed to an ionic state after hydration. This phenomenon was not seen in other amino acids we have studied so far.

Synthesis of chitosan derivative with diethyldithiocarbamate and its antifungal activity.

Science.gov (United States)

Qin, Yukun; Xing, Ronge; Liu, Song; Li, Kecheng; Hu, Linfeng; Yu, Huahua; Chen, Xiaolin; Li, Pengcheng

2014-04-01

With an aim to discover novel chitosan derivatives with enhanced antifungal properties compared with chitosan. Diethyl dithiocarbamate chitosan (EtDTCCS) was investigated and its structure was well identified. The antifungal activity of EtDTCCS against Alternaria porri (A. porri), Gloeosporium theae sinensis Miyake (G. theae sinensis), and Stemphylium solani Weber (S. solani) was tested at 0.25, 0.5, and 1.0 mg/mL, respectively. Compared with plain chitosan, EtDTCCS shows better inhibitory effect with 93.2% inhibitory index on G. theae sinensis at 1.0 mg/mL, even stronger than for polyoxin (82.5%). It was inferred derivatives of this kind may find potential applications for the treatment of various crop-threatening diseases. Copyright © 2014 Elsevier B.V. All rights reserved.

Weak-link capacitor

Science.gov (United States)

Dirk, Shawn M.; Johnson, Ross S.; Wheeler, David R.; Bogart, Gregory R.

2013-04-23

A process for making a dielectric material where a precursor polymer selected from poly(phenylene vinylene)polyacetylene, poly(p-phenylene), poly(thienylene vinylene), poly(1,4-naphthylene vinylene), and poly(p-pyridine vinylene) is energized said by exposure by radiation or increase in temperature to a level sufficient to eliminate said leaving groups contained within the precursor polymer, thereby transforming the dielectric material into a conductive polymer. The leaving group in the precursor polymer can be a chloride, a bromide, an iodide, a fluoride, an ester, an xanthate, a nitrile, an amine, a nitro group, a carbonate, a dithiocarbamate, a sulfonium group, an oxonium group, an iodonium group, a pyridinium group, an ammonium group, a borate group, a borane group, a sulphinyl group, or a sulfonyl group.

Analytical chemical system for the determination of heavy metals and organic compounds. Annual progress report, December 1, 1978-November 30, 1979

Energy Technology Data Exchange (ETDEWEB)

Siggia, S.; Barnes, R.M.

1979-10-24

Progress has been made in the synthesis and characterization of new resins for sequestering inorganic and organic compounds. The capabilities of the poly(dithiocarbamate) resin have been extended, a new poly(acrylamidoxime) resin prepared and characterized, and a series of resins for organic compounds prepared and tested. Limited actual sample analyses have been performed with these resins. A new inductively coupled plasma source, spectrometer, and computer system have been received and they are undergoing tests and installation. With this system in place, the multielement analysis of metals during the forthcoming period will insure the application of sequestering resins to practical analysis of energy-related materials. An automated sample handling and data system has been designed, some components purchased, and construction is scheduled for 1980.

Thermal-kinetic study of natural rubber latex films vulcanized by using gamma radiation; Estudo termo-cinetico de filmes de latex de borracha natural de Hevea brasiliensis vulcanizada por radiacao gama

Energy Technology Data Exchange (ETDEWEB)

Leal, Ana Paula Pinho Rodrigues; Barros, Glaucione Gomes de [Brasilia Univ., DF (Brazil). Inst. de Quimica; Guedes, Selma M.L. [Instituto de Pesquisa em Energia Nuclear, Sao Paulo, SP (Brazil)

1999-07-01

Vulcanization of natural rubber latex by ionization radiation produces the crosslink in disperse latex particles. Advantages over conventional process of vulcanization are: the absence of carcinogenic nitrosamines, low cytotoxicity and better degradation at room conditions, due to mainly to the absence of sulfur, zinc oxide and dithiocarbamates. Thermogravimetric analysis (TG) is the measurement of the weight change of a material as a function of temperature and time. TG data different heat speed provide an alternative model of the kinetics of degradation of polymeric materials. The kinetic studies of this material showed a single degradation process at least for 76,5% of mass loss. The activation energy was 49 Kcal/mol. For higher mass loss (85%) the degradation was characterized by associate mechanism. (author)

PLANT PROTECTION PRODUCT RESIDUES IN AGRICULTURAL PRODUCTS OF SLOVENE ORIGIN FOUND IN 2008

Directory of Open Access Journals (Sweden)

Helena BAŠA ČESNIK

2012-01-01

Full Text Available In the year 2008, 166 apple, bean, carrot, cucumber, lettuce, pear, potato and spinach samples from Slovene producers were analysed for plant protection product residues. The samples were analysed for the presence of 158 different active compounds using three analytical methods. In two samples (1.2% exceeded maximum residue levels (MRLs were determined which is better than the results of the monitoring of pesticide residues in the products of plant origin in the 27 European Union, Member States (EU MS and 2 European Free Trade Association (EFTA States: Norway and Iceland in 2008 (2.2%. The most frequently found active substance in agricultural products was dithiocarbamates. Products which contained 4 or more active substances per sample were apples and pears.

Analytical chemical system for the determination of heavy metals and organic compounds. Annual progress report, December 1, 1978-November 30, 1979

International Nuclear Information System (INIS)

Siggia, S.; Barnes, R.M.

1979-01-01

Progress has been made in the synthesis and characterization of new resins for sequestering inorganic and organic compounds. The capabilities of the poly(dithiocarbamate) resin have been extended, a new poly(acrylamidoxime) resin prepared and characterized, and a series of resins for organic compounds prepared and tested. Limited actual sample analyses have been performed with these resins. A new inductively coupled plasma source, spectrometer, and computer system have been received and they are undergoing tests and installation. With this system in place, the multielement analysis of metals during the forthcoming period will insure the application of sequestering resins to practical analysis of energy-related materials. An automated sample handling and data system has been designed, some components purchased, and construction is scheduled for 1980

Cellular Hsp27 interacts with classical swine fever virus NS5A protein and negatively regulates viral replication by the NF-κB signaling pathway.

Science.gov (United States)

Ling, Shifeng; Luo, Mingyang; Jiang, Shengnan; Liu, Jiayu; Ding, Chunying; Zhang, Qinghuan; Guo, Huancheng; Gong, Wenjie; Tu, Changchun; Sun, Jinfu

2018-05-01

Classical swine fever virus (CSFV) nonstructural protein NS5A is a multifunctional protein functioning in regulation of viral genome replication, protein translation and assembly by interaction with viral or host proteins. Here, heat shock protein 27 (Hsp27) has been identified as a novel binding partner of NS5A by using His tag "pull down" coupled with shotgun LC-MS/MS, with interaction of both proteins further confirmed by co-immunoprecipitation and laser confocal assays. In PK-15 cells, silencing of Hsp27 expression by siRNA enhanced CSFV replication, and upregulation of Hsp27 inhibited viral proliferation. Additionally, we have shown that overexpression of Hsp27 increased NF-κB signaling induced by TNFα. Blocking NF-κB signaling in PK-15 cells overexpressing Hsp27 by ammonium pyrrolidinedithiocarbamate (PDTC) eliminated the inhibition of CSFV replication by Hsp27. These findings clearly demonstrate that the inhibition of CSFV replication by Hsp27 is mediated via the NF-κB signaling pathway. Copyright © 2018 Elsevier Inc. All rights reserved.

Regulation of ROS in transmissible gastroenteritis virus-activated apoptotic signaling

Energy Technology Data Exchange (ETDEWEB)

Ding, Li [College of Veterinary Medicine, Northwest A and F University, Yangling, Shaanxi 712100 (China); College of Life Sciences, Hainan Normal University, Haikou, Hainan 571158 (China); Zhao, Xiaomin; Huang, Yong; Du, Qian; Dong, Feng; Zhang, Hongling; Song, Xiangjun; Zhang, Wenlong [College of Veterinary Medicine, Northwest A and F University, Yangling, Shaanxi 712100 (China); Tong, Dewen, E-mail: dwtong@nwsuaf.edu.cn [College of Veterinary Medicine, Northwest A and F University, Yangling, Shaanxi 712100 (China)

2013-12-06

Highlights: •TGEV infection induced ROS accumulation. •ROS accumulation is involved in TGEV-induced mitochondrial integrity impairment. •ROS is associated with p53 activation and apoptosis occurrence in TGEV-infected cells. -- Abstract: Transmissible gastroenteritis virus (TGEV), an enteropathogenic coronavirus, causes severe lethal watery diarrhea and dehydration in piglets. Previous studies indicate that TGEV infection induces cell apoptosis in host cells. In this study, we investigated the roles and regulation of reactive oxygen species (ROS) in TGEV-activated apoptotic signaling. The results showed that TGEV infection induced ROS accumulation, whereas UV-irradiated TGEV did not promote ROS accumulation. In addition, TGEV infection lowered mitochondrial transmembrane potential in PK-15 cell line, which could be inhibited by ROS scavengers, pyrrolidinedithiocarbamic (PDTC) and N-acetyl-L-cysteine (NAC). Furthermore, the two scavengers significantly inhibited the activation of p38 MAPK and p53 and further blocked apoptosis occurrence through suppressing the TGEV-induced Bcl-2 reduction, Bax redistribution, cytochrome c release and caspase-3 activation. These results suggest that oxidative stress pathway might be a key element in TGEV-induced apoptosis and TGEV pathogenesis.

Synthesis of Unsymmetrical Annulated 2,2’-Bipyridine Analogues with Attached Cycloalkene and Piperidine Rings via Sequential Diels-Alder Reaction of 5,5’-bi-1,2,4-triazinesâ€

Directory of Open Access Journals (Sweden)

D. Branowska

2005-12-01

Full Text Available Synthesis of bisfunctionalized unsymmetrical 2,2’-bipyridines 8 or their sulfonyl derivatives 12a,b are described. They were prepared via the Diels-Alder reaction of 1-methyl-4-pyrrolidin-1-yl-1,2,3,6-tetrahydropyridine (6 with 3,3’-bis(methyl- sulfanyl-5,5’-bi-1,2,4-triazine (1. The reaction leads to the single cycloaddition product 7 which undergoes Diels-Alder reaction with cyclic enamines 2a,b to give unsymmetrical 2,2’-bipyridine derivatives 8, consisting of the two different heterocyclic units: cycloalkeno[c]pyridine and 2,6-naphthyridine.

Design of novel HIV-1 protease inhibitors incorporating isophthalamide-derived P2-P3 ligands: Synthesis, biological evaluation and X-ray structural studies of inhibitor-HIV-1 protease complex

Energy Technology Data Exchange (ETDEWEB)

Ghosh, Arun K.; Brindisi, Margherita; Nyalapatla, Prasanth R.; Takayama, Jun; Ella-Menye, Jean-Rene; Yashchuk, Sofiya; Agniswamy, Johnson; Wang, Yuan-Fang; Aoki, Manabu; Amano, Masayuki; Weber, Irene T.; Mitsuya, Hiroaki

2017-10-01

Based upon molecular insights from the X-ray structures of inhibitor-bound HIV-1 protease complexes, we have designed a series of isophthalamide-derived inhibitors incorporating substituted pyrrolidines, piperidines and thiazolidines as P2-P3 ligands for specific interactions in the S2-S3 extended site. Compound 4b has shown an enzyme Ki of 0.025 nM and antiviral IC50 of 69 nM. An X-ray crystal structure of inhibitor 4b-HIV-1 protease complex was determined at 1.33 Å resolution. We have also determined X-ray structure of 3b-bound HIV-1 protease at 1.27 Å resolution. These structures revealed important molecular insight into the inhibitor–HIV-1 protease interactions in the active site.

Unusual NHC-Iridium(I) Complexes and Their Use in the Intramolecular Hydroamination of Unactivated Aminoalkenes

KAUST Repository

Sipos, Gellé rt; Ou, Arnold; Skelton, Brian W.; Falivene, Laura; Cavallo, Luigi; Dorta, Reto

2016-01-01

N-heterocyclic carbene (NHC) ligands with naphthyl side chains were employed for the synthesis of unsaturated, yet isolable [(NHC)Ir(cod)]+ (cod=1,5-cyclooctadiene) complexes. These compounds are stabilised by an interaction of the aromatic wingtip that leads to a sideways tilt of the NHC-Ir bond. Detailed studies show how the tilting of such N-heterocyclic carbenes affects the electronic shielding properties of the carbene carbon atom and how this is reflected by significant upfield shifts in the 13CNMR signals. When employed in the intramolecular hydroamination, these [(NHC)Ir(cod)]+ species show very high catalytic activity under mild reaction conditions. An enantiopure version of the catalyst system produces pyrrolidines with excellent enantioselectivities. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A new furofuran lignan from Piper terminaliflorum Tseng.

Science.gov (United States)

Liu, Tie; Liang, Qian; Zhang, Xin-Min; Huang, Shen-Yang; Xu, Wen-Hui

2018-02-01

The chemical investigation of whole plants Piper terminaliflorum Tseng led to the isolation of one new furofuran lignan, 7-methoxyasarinin (1), along with three known amide alkaloids (2-4) as N-3,5-dimethoxy-4-hydroxycinnamoylpyrrole (2), dihydropipercide (3) and 1-[(2E,4E,9E)-10-(3,4-Methylenedioxyphenyl)-2,4,9-undecatrienoyl]pyrrolidine (4). Their structures were elucidated by extensive spectroscopic analyses, including 1D, 2D NMR and HR-ESI-MS, and by comparison with the literature. Compounds (2-4) were isolated from Piper terminaliflorum Tseng for the first time. All isolated compounds (1-4) were evaluated for their cytotoxic activities against five human cancer cell lines (including A-549, SMMC-7721, HL-60, MCF-7 and SW-480).

Hydrogen-bonded co-crystal structure of benzoic acid and zwitterionic l-proline

Directory of Open Access Journals (Sweden)

Aaron M. Chesna

2017-03-01

Full Text Available The title compound [systematic name: benzoic acid–pyrrolidin-1-ium-2-carboxylate (1/1], C7H6O2·C5H9NO2, is an example of the application of non-centrosymmetric co-crystallization for the growth of a crystal containing a typically centrosymmetric component in a chiral space group. It co-crystallizes in the space group P212121 and contains benzoic acid and l-proline in equal proportions. The crystal structure exhibits chains of l-proline zwitterions capped by benzoic acid molecules which form a C(5[R33(11] hydrogen-bonded network along [100]. The crystal structure is examined and compared to that of a similar co-crystal containing l-proline zwitterions and 4-aminobenzoic acid.

N-Butoxycarbonyl-5-oxo-l-proline ethyl ester

Directory of Open Access Journals (Sweden)

P. Rajalakshmi

2013-04-01

Full Text Available The molecular structure of the title compound, C12H19NO5, may be visualized as made up of two nearly perpendicular planes [dihedral angle = 87.39 (12°] and its crystal structure is a good example of C—H...O interactions assuming significance in optimizing supramolecular aggregation in crystals in a molecule which is severely imbalanced in terms of donors to acceptor atoms. The pyrrolidine ring adopts a (3T2 twist conformation with puckering parameters Q = 0.2630 (4 Å and ϕ = 59 (9°. The crystal structure features R24(10 and R34(26 ring motifs formed by four weak C—H...O interactions, leading to supramolecular sheets lying parallel to the bc plane.

2,3-Di­phenyl­male­imide 1-methyl­pyrrol­idin-2-one monosolvate

Science.gov (United States)

Bulatov, Evgeny; Boyarskaya, Dina; Chulkova, Tatiana; Haukka, Matti

2014-01-01

In the title compound, C16H11NO2·C5H9NO, the dihedral angles between the male­imide and phenyl rings are 34.7 (2) and 64.8 (2)°. In the crystal, the 2,3-di­phenyl­male­imide and 1-methyl­pyrrolidin-2-one mol­ecules form centrosymmetrical dimers via pairs of strong N—H⋯O hydrogen bonds and π–π stacking inter­actions between the two neighboring male­imide rings [centroid–centroid distance = 3.495 (2) Å]. The dimers are further linked by weak C—H⋯O and C—H⋯π hydrogen bonds into a three-dimensional framework. PMID:24764976

Unusual NHC-Iridium(I) Complexes and Their Use in the Intramolecular Hydroamination of Unactivated Aminoalkenes

KAUST Repository

Sipos, Gellért

2016-04-10

N-heterocyclic carbene (NHC) ligands with naphthyl side chains were employed for the synthesis of unsaturated, yet isolable [(NHC)Ir(cod)]+ (cod=1,5-cyclooctadiene) complexes. These compounds are stabilised by an interaction of the aromatic wingtip that leads to a sideways tilt of the NHC-Ir bond. Detailed studies show how the tilting of such N-heterocyclic carbenes affects the electronic shielding properties of the carbene carbon atom and how this is reflected by significant upfield shifts in the 13CNMR signals. When employed in the intramolecular hydroamination, these [(NHC)Ir(cod)]+ species show very high catalytic activity under mild reaction conditions. An enantiopure version of the catalyst system produces pyrrolidines with excellent enantioselectivities. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Synthesis of carbon-14 and tritium labeled cis-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)cyclohexyl]benzamidehydrochloride, an anticonvulsant agent

International Nuclear Information System (INIS)

Hsi, R.S.P.; Stolle, W.T.; Ayer, D.E.

1992-01-01

The title compound, U-54494A, is an anticonvulsant agent with clinical potential for treating epilepsy and a broad spectrum of seizure disorders. Structurally it is related to kappa opiod agonists and shares their anticonvulsant properties, but appears to be devoid of analgesic, sedative, and diuretic side effects. It also has been shown to inhibit neuronal damage and seizures induced by excitatory amino acids. This report describes the synthesis of the racemic U-54494A labeled with carbon-14 at the carboxamide carbon and with tritium in the pyrrolidine ring at C-3 and C-4. These radioisotope labeled versions of U-54494A were prepared for conducting drug disposition studies of this compound in test animals and human subjects

Photoelectron spectroscopy study of the X-ray-induced decomposition of some gold(III) dithiocarbamates

International Nuclear Information System (INIS)

Attekum, P.M.Th.M. van; Trooster, J.M.

1980-01-01

The factors influencing the decomposition rate of two gold(III) complexes, [AuMe 2 (S 2 CNMe 2 )] and [AuBr 2 (S 2 CNPr 2 sup(n))]; in an X-ray photoelectron spectroscopy experiment have been studied. It is shown that the decomposition rate can be slowed down by using graphite as substrate and by lowering the sample temperature. From the Au(4f) spectrum a direct measure has been made of the shift in the binding energy between Ausup(III) and Ausup(I) and this shift is shown to be dependent on the electronegativity of the ligands. The valence bands of the complexes show a narrow Au(5d) band with a spin-orbit splitting of ca. 1.6 eV. (author)

Syntheses, structures and third-order non-linear optical properties of homometal clusters containing molybdenum

International Nuclear Information System (INIS)

Li Yong; Lu Jing; Cui Xiaobing; Xu Jiqing; Li Kechang; Sun Huaying; Li Guanghua; Pan Lingyun; Yang Qingxin

2005-01-01

Both the homometal cluster [P(ph 4 )] 2 [Mo 2 O 2 (μ-S) 2 (S 2 ) 2 ] (1) and [Mo 2 O 2 (μ-S) 2 (Et 2 dtc) 2 ] (2) (Et 2 dtc=diethyl-dithiocarbamate) were successfully synthesized by low-temperature solid-state reactions. X-ray single-crystal diffraction studies suggest that compound (1) is a dinuclear anion cluster, and compound (2) is a dinuclear neutral cluster. The two compounds were characterized by elemental analyses, IR spectra and UV-Vis spectra. The third-order non-linear optical (NLO) properties of the clusters were also investigated and all exhibited nice non-linear absorption and self-defocusing performance with moduli of the hyperpolarizabilities 5.145x10 -30 esu for (1) and 5.428x10 -30 esu for (2)

Gold nanoparticle-based optical microfluidic sensors for analysis of environmental pollutants

DEFF Research Database (Denmark)

Lafleur, Josiane P.; Senkbeil, Silja; Jensen, Thomas G.

2012-01-01

Conventional methods of environmental analysis can be significantly improved by the development of portable microscale technologies for direct in-field sensing at remote locations. This report demonstrates the vast potential of gold nanoparticle-based microfluidic sensors for the rapid, in......-field, detection of two important classes of environmental contaminants – heavy metals and pesticides. Using gold nanoparticle-based microfluidic sensors linked to a simple digital camera as the detector, detection limits as low as 0.6 μg L−1 and 16 μg L−1 could be obtained for the heavy metal mercury...... and the dithiocarbamate pesticide ziram, respectively. These results demonstrate that the attractive optical properties of gold nanoparticle probes combine synergistically with the inherent qualities of microfluidic platforms to offer simple, portable and sensitive sensors for environmental contaminants....

Analysis of medicinal plant extracts by neutron activation method

International Nuclear Information System (INIS)

Vaz, Sandra Muntz

1995-01-01

This dissertation has presented the results from analysis of medicinal plant extracts using neutron activation method. Instrumental neutron activation analysis was applied to the determination of the elements Al, Br, Ca, Ce, Cl, Cr, Cs, Fe, K, La, Mg, Mn, Na, Rb, Sb, Sc and Zn in medicinal extracts obtained from Achyrolcline satureoides DC, Casearia sylvestris, Centella asiatica, Citrus aurantium L., Solano lycocarpum, Solidago microglossa, Stryphnondedron barbatiman and Zingiber officinale R. plants. The elements Hg and Se were determined using radiochemical separation by means of retention of Se in HMD inorganic exchanger and solvent extraction of Hg by bismuth diethyl-dithiocarbamate solution. Precision and accuracy of the results have been evaluated by analysing reference materials. The therapeutic action of some elements found in plant extracts analyzed was briefly discussed

Analysis of medicinal plant extracts by neutron activation method; Analise de extratos de plantas medicinais pelo metodo de ativacao com neutrons

Energy Technology Data Exchange (ETDEWEB)

Vaz, Sandra Muntz

1996-12-31

This dissertation has presented the results from analysis of medicinal plant extracts using neutron activation method. Instrumental neutron activation analysis was applied to the determination of the elements Al, Br, Ca, Ce, Cl, Cr, Cs, Fe, K, La, Mg, Mn, Na, Rb, Sb, Sc and Zn in medicinal extracts obtained from Achyrolcline satureoides DC, Casearia sylvestris, Centella asiatica, Citrus aurantium L., Solano lycocarpum, Solidago microglossa, Stryphnondedron barbatiman and Zingiber officinale R. plants. The elements Hg and Se were determined using radiochemical separation by means of retention of Se in HMD inorganic exchanger and solvent extraction of Hg by bismuth diethyl-dithiocarbamate solution. Precision and accuracy of the results have been evaluated by analysing reference materials. The therapeutic action of some elements found in plant extracts analyzed was briefly discussed 70 refs., 13 figs., 15 tabs

In Situ Monitoring of RAFT Polymerization by Tetraphenylethylene-Containing Agents with Aggregation-Induced Emission Characteristics.

Science.gov (United States)

Liu, Shunjie; Cheng, Yanhua; Zhang, Haoke; Qiu, Zijie; Kwok, Ryan T K; Lam, Jacky W Y; Tang, Ben Zhong

2018-05-22

A facile and efficient approach is demonstrated to visualize the polymerization in situ. A group of tetraphenylethylene (TPE)-containing dithiocarbamates were synthesized and screened as agents for reversible addition fragmentation chain transfer (RAFT) polymerizations. The spatial-temporal control characteristics of photochemistry enabled the RAFT polymerizations to be ON and OFF on demand under alternating visible light irradiation. The emission of TPE is sensitive to the local viscosity change owing to its aggregation-induced emission characteristic. Quantitative information could be easily acquired by the naked eye without destroying the reaction system. Furthermore, the versatility of such a technique was well demonstrated by 12 different polymerization systems. The present approach thus demonstrated a powerful platform for understanding the controlled living radical polymerization process. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Analysis of medicinal plant extracts by neutron activation method; Analise de extratos de plantas medicinais pelo metodo de ativacao com neutrons

Energy Technology Data Exchange (ETDEWEB)

Vaz, Sandra Muntz

1995-12-31

This dissertation has presented the results from analysis of medicinal plant extracts using neutron activation method. Instrumental neutron activation analysis was applied to the determination of the elements Al, Br, Ca, Ce, Cl, Cr, Cs, Fe, K, La, Mg, Mn, Na, Rb, Sb, Sc and Zn in medicinal extracts obtained from Achyrolcline satureoides DC, Casearia sylvestris, Centella asiatica, Citrus aurantium L., Solano lycocarpum, Solidago microglossa, Stryphnondedron barbatiman and Zingiber officinale R. plants. The elements Hg and Se were determined using radiochemical separation by means of retention of Se in HMD inorganic exchanger and solvent extraction of Hg by bismuth diethyl-dithiocarbamate solution. Precision and accuracy of the results have been evaluated by analysing reference materials. The therapeutic action of some elements found in plant extracts analyzed was briefly discussed 70 refs., 13 figs., 15 tabs

Macroradical initiated polymerisation of acrylic and methacrylic monomers.

Science.gov (United States)

Mijangos, Irene; Guerreiro, António; Piletska, Elena; Whitcombe, Michael J; Karim, Kal; Chianella, Iva; Piletsky, Sergey

2009-10-01

An approach has been developed for the grafting of monomers onto poly(trimethylolpropane trimethacrylate) (polyTRIM) particles using 2,2-diethyl dithiocarbamic acid benzyl ester (DDCABE) as an initiator. A set of polymers was prepared with this technique over different lengths of time and the kinetics of the reaction studied experimentally. It was found that the grafting of initiator to the polymeric support followed a second order reaction, while the subsequent addition of monomers from solution into the polyTRIM macroradicals followed a first order reaction. The living nature of the iniferter modified macroradicals permits easy consecutive grafting of multiple polymeric layers, allowing straightforward functionalisation of particles. However, the effectiveness of the grafted initiator decreased with each cycle of polymerisation. This technique can be used for a wide range of applications in analytical and biochemistry.

A conformational study of proline derivatives

Directory of Open Access Journals (Sweden)

M.E. Kamwaya

2002-12-01

Full Text Available From the study of the structures and molecular conformations of a number of proline derivatives, some conclusions were drawn. The widening effect of angle Cα-C'-N' is caused by steric repulsion between a hydrogen atom at Cα of the preceding prolyl residue with any other at either Cα or Cδ of the pyrrolidine ring cis to it. This effect is influenced by the distance between the said hydrogen atoms: the nearer this distance is, the greater is the steric repulsion and the wider is the angle of steric repulsion. The ratio of the angle of steric repulsion to the distance between Cα and the following Cα (or Cδ cis to it is approximately 40 and 41 for peptides with trans and cis configurations, respectively. The torsion angle ranges for χ1, χ3, χ 4, θ and φ in these derivatives are widened more than usual. The highest vibration, which more often takes place at either the Cβ or Cγ of the pyrrolidine ring, does so not necessarily at the one that is puckered. A Δ&psi -relationship is established, for the determination of α-helixity or collageneity, also in small peptides and amino acids that contain proline. The Δ&psi-relationship is versatile and gives about +180o and –180o for the two categories, respectively. The distance between the carbonyl and hydroxyl (or otherwise terminal end atoms is minimal (2.2 Å and constant, for all peptides. The ratios of the angles at the carbonyl carbons (O'-C'-N' or (O'-C'-O' to this distance is also constant: 56 and 57 for the cis and trans confirgurations, respectively; i.e. a proline O'-C'-N'- (or O'-C'-O'-test, hereinafter called the CT-test, has been established for the determination of cis and trans configurations. It is also established in these proline derivatives, that whereas puckering takes place at Cβ for the CS form, it does so at Cγ for the C2 form.

Simultaneous determination of piracetam and its four impurities by RP-HPLC with UV detection.

Science.gov (United States)

Arayne, M Saeed; Sultana, Najma; Siddiqui, Farhan Ahmed; Mirza, Agha Zeeshan; Qureshi, Faiza; Zuberi, M Hashim

2010-08-01

A simple and rapid high-performance liquid chromatographic method for the separation and determination of piracetam and its four impurities, 2-oxopyrrolidin-1-yl)acetic acid, pyrrolidin-2-one, methyl (2-oxopyrrolidin-1-yl)acetate, and ethyl (2-oxopyrrolidin-1-yl)acetate, was developed. The separation was achieved on a reversed-phase C(18) Nucleosil column (25 cm x 0.46 cm, 10 microm). The mobile phase is composed of an aqueous solution containing 0.2 g/L of triethyl amine-acetonitrile (85:15, v/v). The pH of the mobile phase was adjusted to 6.5 with phosphoric acid at a flow rate of 1 mL/min at ambient temperature and UV detection at 205 nm. The developed method was found to give good separation between the pure drug and its four related substance. The polynomial regression data for the calibration plots showed good linear relationship in the concentration range of 50-10,000 ng/mL, 25-10,000 ng/mL, 45-10,000 ng/mL, 34-10,000 ng/mL, and 55-10,000 ng/mL, respectively, with r(2) = 0.9999. The method was validated for precision, accuracy, ruggedness, and recovery. The minimum quantifiable amounts were found to be 50 ng/mL of piracetam, 25 ng/mL of 2-oxopyrrolidin-1-yl)acetic acid, 45 ng/mL of pyrrolidin-2-one, 34 ng/mL of methyl (2-oxopyrrolidin-1-yl)acetate, and 55 ng/mL of ethyl (2-oxopyrrolidin-1-yl)acetate. Statistical analysis proves that the method is reproducible and selective for the estimation of piracetam as well as its related substance. As the method could effectively separate the drug from the related substances, it can be employed as a stability-indicating one. The proposed method shows high efficiency, allowing the separation of the main component piracetam from other impurities.

DFT studies of the substituent effects of dimethylamino on non-heme active oxidizing species: iron(V)-oxo species or iron(IV)-oxo acetate aminopyridine cation radical species?

Science.gov (United States)

Wang, Fang; Sun, Wei; Xia, Chungu; Wang, Yong

2017-10-01

Through the introduction of dimethylamino (Me 2 N) substituent at the pyridine ring of 2-((R)-2-[(R)-1-(pyridine-2-ylmethyl)pyrrolidin-2-yl]pyrrolidin-1-ylmethyl)pyridine (PDP) ligand, the non-heme Fe II ( Me2N PDP)/H 2 O 2 /AcOH catalyst system was found to exhibit significant higher catalytic activity and enantioselectivity than the non-substituent one in the asymmetric epoxidation experiments. The mechanistic origin of the remarkable substituent effects in these oxidation reactions has not been well established. To ascertain the potent oxidant and the related reaction mechanism, a detailed DFT calculation was performed. Interestingly, a novel Fe(IV)-oxo Me2N PDP cation radical species, [( Me2N PDP) + · Fe IV (O)(OAc)] 2+ ( Me2N 5), with about one spin spreading over the non-heme Me2N PDP ligand was formed via a carboxylic-acid-assisted O-O bond heterolysis, which is reminiscent of Compound I (an Fe(IV)(O)(porphyrin cation radical) species) in cytochrome P450 chemistry. Me2N 5 is energetically comparable with the cyclic ferric peracetate species Me2N 6, while in the pristine Fe(PDP) catalyst system, H 6 is more stable than H 5. Comparison of the activation energy for the ethylene epoxidation promoted by Me2N 5 and Me2N 6, Me2N 5 is supposed as the true oxidant triggering the epoxidation of olefins. In addition, a systematic research on the substituent effects varied from the electron-donating substituent (dMM, the substituents at sites 3, 4, and 5 of the pyridine ring: methyl, methoxyl, and methyl) to the electron-withdrawing one (CF 3 , 2,6-bis(trifluoromethyl)phenyl) on the electronic structure of the reaction intermediates has also been investigated. An alternative cyclic ferric peracetate complex is obtained, indicating that the substituents at the pyridine ring of PDP ligands have significant impacts on the electronic structure of the oxidants.

New One-Pot Methodologies for the Modification or Synthesis of Alkaloid Scaffolds

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Amir E. Wahba

2010-08-01

Full Text Available There are several avenues by which promising bioactive natural products can be produced in sufficient quantities to enable lead optimization and medicinal chemistry studies. The total synthesis of natural products is an important, but sometimes difficult, approach and requires the development of innovative synthetic methodologies to simplify the synthesis of complex molecules. Various classes of natural product alkaloids are both common and widely distributed in plants, bacteria, fungi, insects and marine organisms. This mini-review will discuss the scope, mechanistic insights and enantioselectivity aspects of selected examples of recently developed one-pot methods that have been published in 2009 for the synthesis of substituted piperidines, quinolizidines, pyrrolidines, hexahydropyrrolizines, octahydroindolizines and g-lactams. In addition, progress on the synthesis of b-carboline (manzamine alkaloids will also be discussed.

Penicillenols from a deep-sea fungus Aspergillus restrictus inhibit Candida albicans biofilm formation and hyphal growth.

Science.gov (United States)

Wang, Jie; Yao, Qi-Feng; Amin, Muhammad; Nong, Xu-Hua; Zhang, Xiao-Yong; Qi, Shu-Hua

2017-06-01

Penicillenols (A1, A2, B1, B2, C1 and C2) were isolated from Aspergillus restrictus DFFSCS006, and could differentially inhibit biofilm formation and eradicate pre-developed biofilms of Candida albicans. Their structure-bioactivity relationships suggested that the saturation of hydrocarbon chain at C-8, R-configuration of C-5 and trans-configuration of the double bond between C-5 and C-6 of pyrrolidine-2,4-dione unit were important for their anti-biofilm activities. Penicillenols A2 and B1 slowed the hyphal growth and suppressed the transcripts of hypha specific genes HWP1, ALS1, ALS3, ECE1 and SAP4. Moreover, penicillenols A2 and B1 were found to act synergistically with amphotericin B against C. albicans biofilm formation.

New and Efficient Synthesis of Amides from Acid Chlorides Using Diisobutyl(amino)aluminum

Energy Technology Data Exchange (ETDEWEB)

Park, Jae Kyo; Shin, Won Kyu; An, Duk Keun [Kangwon National Univ., Chuncheon (Korea, Republic of)

2013-05-15

In conclusion, we have developed a facile, alternative method for the formation of secondary and tertiary amides including morpholine amides from acid chlorides by using diisobutyl(amino)aluminum under mild reaction conditions. The advantages of the present method include the high product yields, simple experimental procedure, short reaction time (10 min), and the fact that an excess amount of amine is not required. This result suggests that our new method can provide an alternative method for the synthesis of useful amides from acid chlorides. Amides are valuable functional groups in biological, agrochemical, and pharmaceutical molecules. Several amides such as Weinreb amides, morpholine amides, and pyrrolidine amides are useful intermediates for the synthesis of aldehydes or ketones. Among them, morpholine amides are a cheap and good substitute for Weinreb amides.

The stereochemistry of the addition of chlorotitanium enolates of N-acyl oxazolidin-2-ones to 5- and 6- membered N-acyliminium ions

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Pilli Ronaldo A.

2001-01-01

Full Text Available The stereoselective addition of chiral and achiral titanium enolates derived from the corresponding N-acyl oxazolidin-2-ones to 5- and 6- membered N-acyliminium ions afforded 2-substituted pyrrolidines in moderate to good diastereoisomeric ratio (5:1 to 14:1 while lower diastereoselection was generally observed in the formation of the corresponding 2-substituted piperidines. The stereochemical outcome was found to be modulated by the nature of the cyclic N-acyliminium ion (5- or 6-membered and of its carbamate and by the N-acyl group in the enolate precursor. The preferential lk approach seems to be dictated mainly by the minimization of non-bonding interactions between the N-acyl group in the chlorotitanium (IV enolate and the carbamate and methylene groups in the cyclic N-acyliminium ion.

Fulleropyrrolidine end-capped molecular wires for molecular electronics--synthesis, spectroscopic, electrochemical, and theoretical characterization

DEFF Research Database (Denmark)

Sørensen, Jakob Kryger; Fock, Jeppe; Pedersen, Anders Holmen

2011-01-01

In continuation of previous studies showing promising metal-molecule contact properties a variety of C(60) end-capped "molecular wires" for molecular electronics were prepared by variants of the Prato 1,3-dipolar cycloaddition reaction. Either benzene or fluorene was chosen as the central wire...... state. However, the fluorescence of C(60) was quenched by charge transfer from the wire to C(60). Quantum chemical calculations predict and explain the collapse of coherent electronic transmission through one of the fulleropyrrolidine-terminated molecular wires......., and synthetic protocols for derivatives terminated with one or two fullero[c]pyrrolidine "electrode anchoring" groups were developed. An aryl-substituted aziridine could in some cases be employed directly as the azomethine ylide precursor for the Prato reaction without the need of having an electron...

New and Efficient Synthesis of Amides from Acid Chlorides Using Diisobutyl(amino)aluminum

International Nuclear Information System (INIS)

Park, Jae Kyo; Shin, Won Kyu; An, Duk Keun

2013-01-01

In conclusion, we have developed a facile, alternative method for the formation of secondary and tertiary amides including morpholine amides from acid chlorides by using diisobutyl(amino)aluminum under mild reaction conditions. The advantages of the present method include the high product yields, simple experimental procedure, short reaction time (10 min), and the fact that an excess amount of amine is not required. This result suggests that our new method can provide an alternative method for the synthesis of useful amides from acid chlorides. Amides are valuable functional groups in biological, agrochemical, and pharmaceutical molecules. Several amides such as Weinreb amides, morpholine amides, and pyrrolidine amides are useful intermediates for the synthesis of aldehydes or ketones. Among them, morpholine amides are a cheap and good substitute for Weinreb amides

Gas phase radiolysis and vacuum ultraviolet photolysis of heterocyclic organic compounds. Progress report, February 1, 1974--February 1, 1975

International Nuclear Information System (INIS)

Scala, A.A.; Salomon, D.; Colon, I.; D'Angona, J.

1975-01-01

In the γ radiolysis of tetrahydrofuran there are pronounced density effects in the pressure range from 0 to 50 Torr with the most important ion-pair yields decreasing as the pressure increases. The relative product yields of the radiolysis is compared with that of xenon photolysis. Possible mechanisms to explain the results obtained are discussed. The ion-pair yields from the γ radiolysis of the heterocyclic amines, ethylenimine, azetidine, pyrrolidine, and piperidine, are determined, and the pressure effects are evaluated. Reactions mechanisms are discussed. The vacuum ultraviolet photolysis products of thietane and tetrahydrothiophene are studied and compared with the γ radiolysis products. Reaction mechanisms are discussed. The status of the construction of a photoionization mass spectrometer and the measurement of the ionization efficiencies and extinction coefficients of organic compounds is reported. (U.S.)

Ultra-bright and highly efficient inorganic based perovskite light-emitting diodes

Science.gov (United States)

Zhang, Liuqi; Yang, Xiaolei; Jiang, Qi; Wang, Pengyang; Yin, Zhigang; Zhang, Xingwang; Tan, Hairen; Yang, Yang (Michael); Wei, Mingyang; Sutherland, Brandon R.; Sargent, Edward H.; You, Jingbi

2017-06-01

Inorganic perovskites such as CsPbX3 (X=Cl, Br, I) have attracted attention due to their excellent thermal stability and high photoluminescence quantum efficiency. However, the electroluminescence quantum efficiency of their light-emitting diodes was CsPbBr3 lattice and by depositing a hydrophilic and insulating polyvinyl pyrrolidine polymer atop the ZnO electron-injection layer to overcome these issues. As a result, we obtained light-emitting diodes exhibiting a high brightness of 91,000 cd m-2 and a high external quantum efficiency of 10.4% using a mixed-cation perovskite Cs0.87MA0.13PbBr3 as the emitting layer. To the best of our knowledge, this is the brightest and most-efficient green perovskite light-emitting diodes reported to date.

Di-n-butylbis[N-(2-methoxyethyl-N-methyldithiocarbamato-κ2S,S′]tin(IV: crystal structure and Hirshfeld surface analysis

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Rapidah Mohamad

2017-02-01

Full Text Available The complete molecule of the title compound, [Sn(C4H92(C5H10NOS22], is generated by a crystallographic mirror plane, with the SnIV atom and the two inner methylene C atoms of the butyl ligands lying on the mirror plane; statistical disorder is noted in the two terminal ethyl groups, which deviate from mirror symmetry. The dithiocarbamate ligand coordinates to the metal atom in an asymmetric mode with the resulting C2S4 donor set defining a skew trapezoidal bipyramidal geometry; the n-butyl groups are disposed to lie over the longer Sn—S bonds. Supramolecular chains aligned along the a-axis direction and sustained by methylene-C—H...S(weakly coordinating interactions feature in the molecular packing. A Hirshfeld surface analysis reveals the dominance of H...H contacts in the crystal.

Specific non-bonding contacts in the crystal structure of [Mo3(μ3-S)(μ-S2)3(S2CNEt2)3]Cl0.53Br0.47 solid solution

International Nuclear Information System (INIS)

Virovets, A.V.; Volkov, O.V.

2000-01-01

Solid solution [Mo 3 S 7 (dtc) 3 ]Cl 0.53 Br 0.47 (dtc diethyl-dithiocarbamate) featuring the following parameters of monoclinic all: a = 14.541(2), b = 12.407(2), c = 18.117(2) A, β = 90.032(9) deg, sp.gr. P2 1 /n, Z = 4, d cal = 2.107 g/cm 3 , was studied by the method of X-ray diffraction analysis. Formation of ionic pairs with axial contact 3S ax ...Br, its length 3.028-3.105 A, in the compound structure was ascertained. For compounds [Mo 3 S 7 (dtc) 3 ] Hal (Hal = Cl, Br, I) a regular growth in S...Hal distances in the series Cl-Br-I was pointed out, meanwhile the distances remained shorted than the van-der-Waals sums of sulfur and halogen radii [ru

Carcinogenicity tests of certain environmental and industrial chemicals

International Nuclear Information System (INIS)

Weisburger, E.K.; Ulland, B.M.; Nam, J.; Gart, J.J.; Weisburger, J.H.

1981-01-01

Fourteen chemicals of varied uses were tested for carcinogenicity by oral administration in male and female Charles River CD rats. Under the conditions of the tests, propane sultone, propylene imine, and ethylenethiourea, in addition to the positive control N-2-fluorenylacetamide, were carcinogenic. Avadex, bis(2-chloroethyl) ether, the potassium salt of bis(2-hydroxyethyl) dithiocarbamic acid, ethylene carbonate, and semicarbazide hydrochloride were not carcinogenic under the test conditions. Dithiooxamide, glycerol alpha-monochlorohydrin, and thiosemicarbazide gave somewhat ambiguous results, though administered at high enough dose levels to be toxic. An inadequate number of animals survived treatments with sodium azide, sodium bisulfide, and vinylene carbonate, or the animals may not have received sufficiently high doses of the test chemicals to provide maximum test sensitivity. However, there were no indications that these three chemicals were carcinogenic under the test conditions

Non-omnia moriantur-toxicity of mancozeb on dead wood microarthropod fauna.

Science.gov (United States)

Adamski, Zbigniew; Bloszyk, Jerzy; Bruin, Jan; Ziemnicki, Kazimierz

2007-01-01

The effect of Dithane M-45 (dithiocarbamate fungicide; active substance: mancozeb) was studied on microarthropod fauna inhabiting dead wood. Although the exposure was almost never 100% lethal for the majority of observed taxa, almost all (Mesostigmata, Oribatida, some Uropodina, Actinedida, Collembola and Diplopoda) showed very high correlation between concentration of the fungicide and mortality (r > 0.86). Only Stigmaeidae showed low correlation (r = 0.293). For the majority of taxa LC(50 )values were close to the concentrations used during agrochemical activities in woods. Only Trachytes aegrota showed full susceptibility to the fungicide within the range of recommended field concentrations used in forestry (characterised by the low LC(95 )value). Tolerance of mesostigmatid and oribatid mites was found to differ between juveniles and adults, but not consistently. Related Uropodina species varied in susceptibility to the fungicide.

Autoradiographic and metabolic studies of Mycobacterium leprae

International Nuclear Information System (INIS)

Khanolkar, S.R.; Ambrose, E.J.; Chulawala, R.G.; Bapat, C.V.

1978-01-01

Highly purified suspensions of Mycobacterium leprae show a progressive increase in incorporation of [ 3 H]thymidine and [ 3 H]DOPA in short-term cultures as shown by scintillation counting. The intact bacilli are known to have a high permeability barrier. The experiments described suggest that [ 3 H]DOPA becomes trapped within this barrier and oxidized inside the bacilli. Tests by pre-treatment with diethyl dithiocarbamate (DDC inhibitor of DOPA), cold DOPA or hyaluronidase distinguish the uptake of [ 3 H]DOPA by bacilli from the effects of connective tissue contamination. Similar increases in labelling of bacilli by scintillation counting of cultures, have been observed by autoradiography of the organisms. The scintillation method shows promise for rapidly identifying drug resistance in lepromatous patients relapsing while on treatment with dapsone (DDS) rifampicin, clofazimine or other anti-leprosy drugs. (author)

p55PIK regulates alpha-fetoprotein expression through the NF-κB signaling pathway.

Science.gov (United States)

Ye, Guoguo; Sun, Ge; Cheng, Zhikui; Zhang, Lei; Hu, Kanghong; Xia, Xianmin; Zhou, Yin

2017-12-15

Alpha-fetoprotein (AFP) is regarded as a diagnostic and prognostic biomarker and a potential therapeutic target for hepatocellular carcinoma (HCC). However, the regulation of AFP expression in HCC remains poorly understood. This study aimed to investigate the mechanism by which AFP expression is regulated by p55PIK, an isoform of PI3K. Human HCC cell lines (HepG2 and Huh-7) were treated with p55PIK specific competitive inhibitor or shRNA, or p55PIK overexpression vector, in the absence or presence of NF-κB inhibitor PDTC. AFP expression was detected by quantitative real-time PCR and Western blotting. NF-κB responsive elements in AFP enhancer region were characterized by luciferase reporter assay. p55PIK significantly stimulated the expression of AFP by activating NF-κB signaling pathway in HCC cells. Furthermore, two NF-κB binding sites in AFP enhancer region were identified to be primarily responsible for p55PIK mediated upregulation of AFP expression. p55PIK/NF-κB signaling plays an important role in the upregulation of AFP expression in HCC. Copyright © 2017 Elsevier Inc. All rights reserved.