Stereoselective synthesis, X-ray analysis, computational studies and biological evaluation of new thiazole derivatives as potential anticancer agents.

Science.gov (United States)

Mabkhot, Yahia N; Alharbi, Mohammed M; Al-Showiman, Salim S; Ghabbour, Hazem A; Kheder, Nabila A; Soliman, Saied M; Frey, Wolfgang

2018-05-11

The synthesis of new thiazole derivatives is very important because of their diverse biological activities. Also , many drugs containing thiazole ring in their skeletons are available in the market such as Abafungin, Acotiamide, Alagebrium, Amiphenazole, Brecanavir, Carumonam, Cefepime, and Cefmatilen. Ethyl cyanoacetate reacted with phenylisothiocyanate, chloroacetone, in two different basic mediums to afford the thiazole derivative 6, which reacted with dimethylformamide- dimethyl acetal in the presence of DMF to afford the unexpected thiazole derivative 11. The structures of the thiazoles 6 and 11 were optimized using B3LYP/6-31G(d,p) method. The experimentally and theoretically geometric parameters agreed very well. Also, the natural charges at the different atomic sites were predicted. HOMO and LUMO demands were discussed. The anticancer activity of the prepared compounds was evaluated and showed moderate activity. Synthesis of novel thiazole derivatives was done. The structure was established using X-ray and spectral analysis. Optimized molecular structures at the B3LYP/6-31G(d,p) level were investigated. Thiazole derivative 11 has more electropositive S-atom than thiazole 6. The HOMO-LUMO energy gap is lower in the former compared to the latter. The synthesized compounds showed moderate anticancer activity.

Biologically Active Macrocyclic Compounds – from Natural Products to Diversity‐Oriented Synthesis

DEFF Research Database (Denmark)

Madsen, Charlotte Marie; Clausen, Mads Hartvig

2011-01-01

Macrocyclic compounds are attractive targets when searching for molecules with biological activity. The interest in this compound class is increasing, which has led to a variety of methods for tackling the difficult macrocyclization step in their synthesis. This microreview highlights some recent...... developments in the synthesis of macrocycles, with an emphasis on chemistry developed to generate libraries of putative biologically active compounds....

Opportunities for Merging Chemical and Biological Synthesis

Science.gov (United States)

Wallace, Stephen; Balskus, Emily P.

2014-01-01

Organic chemists and metabolic engineers use largely orthogonal technologies to access small molecules like pharmaceuticals and commodity chemicals. As the use of biological catalysts and engineered organisms for chemical production grows, it is becoming increasingly evident that future efforts for chemical manufacture will benefit from the integration and unified expansion of these two fields. This review will discuss approaches that combine chemical and biological synthesis for small molecule production. We highlight recent advances in combining enzymatic and non-enzymatic catalysis in vitro, discuss the application of design principles from organic chemistry for engineering non-biological reactivity into enzymes, and describe the development of biocompatible chemistry that can be interfaced with microbial metabolism. PMID:24747284

Biological synthesis of nanoparticles in biofilms.

Science.gov (United States)

Tanzil, Abid H; Sultana, Sujala T; Saunders, Steven R; Shi, Liang; Marsili, Enrico; Beyenal, Haluk

2016-12-01

The biological synthesis of nanoparticles (NPs) by bacteria and biofilms via extracellular redox reactions has received attention because of the minimization of harmful chemicals, low cost, and ease of culturing and downstream processing. Bioreduction mechanisms vary across bacteria and growth conditions, which leads to various sizes and shapes of biosynthesized NPs. NP synthesis in biofilms offers additional advantages, such as higher biomass concentrations and larger surface areas, which can lead to more efficient and scalable biosynthesis. Although biofilms have been used to produce NPs, the mechanistic details of NP formation are not well understood. In this review, we identify three critical areas of research and development needed to advance our understanding of NP production by biofilms: 1) synthesis, 2) mechanism and 3) stabilization. Advancement in these areas could result in the biosynthesis of NPs that are suitable for practical applications, especially in drug delivery and biocatalysis. Specifically, the current status of methods and mechanisms of nanoparticle synthesis and surface stabilization using planktonic bacteria and biofilms is discussed. We conclude that the use of biofilms to synthesize and stabilize NPs is underappreciated and could provide a new direction in biofilm-based NP production. Copyright © 2016 Elsevier Inc. All rights reserved.

Gold-Pluronic core-shell nanoparticles: synthesis, characterization and biological evaluation

Energy Technology Data Exchange (ETDEWEB)

Simon, Timea; Boca, Sanda [Babes-Bolyai University, Nanobiophotonics and Laser Microspectroscopy Center, Interdisciplinary Research Institute on Bio-Nano-Sciences and Faculty of Physics (Romania); Biro, Dominic [Sapientia University, Department of Mechanical Engineering, Faculty of Technical and Human Sciences (Romania); Baldeck, Patrice [Universite Joseph Fourier and CNRS, Laboratoire Interdisciplinaire de Physique, UMR 5588, CNRS (France); Astilean, Simion, E-mail: simion.astilean@phys.ubbcluj.ro [Babes-Bolyai University, Nanobiophotonics and Laser Microspectroscopy Center, Interdisciplinary Research Institute on Bio-Nano-Sciences and Faculty of Physics (Romania)

2013-04-15

This study presents the synthesis of gold-Pluronic core-shell nanoparticles by a two-step method and investigates their biological impact on cancer cells, specifically nanoparticle internalization and cytotoxicity. Uniform, 9-10-nm-sized, hydrophobic gold nanoparticles were synthesized in organic phase by reducing gold salt with oleylamine, after which oleylamine-protected gold nanoparticles were phase-transferred into aqueous medium using Pluronic F127 block copolymer, resulting in gold-Pluronic core-shell nanoparticles with a mean hydrodynamic diameter of {approx}35 nm. The formation and phase-transfer of gold nanoparticles were analyzed by UV-Vis absorption spectroscopy, transmission electron microscopy, and dynamic light scattering. The obtained gold-Pluronic core-shell nanoparticles proved to be highly stable in salted solution. Cytotoxicity tests showed no modification of cellular viability in the presence of properly purified particles. Furthermore, dark-field cellular imaging demonstrated that gold-Pluronic nanoparticles were able to be efficiently uptaken by cells, being internalized through nonspecific endocytosis. The high stability, proven biocompatibility, and imaging properties of gold-Pluronic core-shell nanoparticles hold promise for relevant intracellular applications, with such a design providing the feasibility to combine all multiple functionalities in one nanoparticle for simultaneous detection and imaging.

Gold–Pluronic core–shell nanoparticles: synthesis, characterization and biological evaluation

International Nuclear Information System (INIS)

Simon, Timea; Boca, Sanda; Biro, Dominic; Baldeck, Patrice; Astilean, Simion

2013-01-01

This study presents the synthesis of gold–Pluronic core–shell nanoparticles by a two-step method and investigates their biological impact on cancer cells, specifically nanoparticle internalization and cytotoxicity. Uniform, 9–10-nm-sized, hydrophobic gold nanoparticles were synthesized in organic phase by reducing gold salt with oleylamine, after which oleylamine-protected gold nanoparticles were phase-transferred into aqueous medium using Pluronic F127 block copolymer, resulting in gold–Pluronic core–shell nanoparticles with a mean hydrodynamic diameter of ∼35 nm. The formation and phase-transfer of gold nanoparticles were analyzed by UV–Vis absorption spectroscopy, transmission electron microscopy, and dynamic light scattering. The obtained gold–Pluronic core–shell nanoparticles proved to be highly stable in salted solution. Cytotoxicity tests showed no modification of cellular viability in the presence of properly purified particles. Furthermore, dark-field cellular imaging demonstrated that gold–Pluronic nanoparticles were able to be efficiently uptaken by cells, being internalized through nonspecific endocytosis. The high stability, proven biocompatibility, and imaging properties of gold–Pluronic core–shell nanoparticles hold promise for relevant intracellular applications, with such a design providing the feasibility to combine all multiple functionalities in one nanoparticle for simultaneous detection and imaging.

Synthesis of C-di-saccharidic compounds by radical cyclisation. Study of biological, structural and dynamic properties

International Nuclear Information System (INIS)

Rubinstenn, Gilles

1996-01-01

The synthesis of carbohydrate mimics and particularly of C-disaccharides, molecules in which the inter-glycosidic oxygen atom has been replaced by a methylene group, has become, this past two decades, an important challenge in organic chemistry. In the first chapter we present the synthesis of C-disaccharides from the neutral series by a silaketal tethering. The key step of this C-glycosylation is a radical macro-cyclisation. This strategy is applied to the synthesis of two analogues of natural, biologically active, products, the lactose and the Lewis x tri-saccharide. The biological activity of this mimetics is then evaluated. A new tethering strategy, based on the use of phosphorus III compounds, is applied, in the second chapter, to the building of C-disaccharides of the 2'-amino 2'- deoxy series. The third chapter deals with the structural and dynamics study of the C-glycosides prepared in chapter 1 by Nuclear Magnetic Resonance. A new methodology, studying the dipolar relaxation along an effective field, generated through an off-resonance RF field, allowed the precise measurement of longitudinal and transverse cross-relaxation rates. Structural and dynamics parameter thus derived are used as restraints for molecular modeling. The results of this study are then compared to those of the biological tests. (author) [fr

Synthesis and biological evaluation of new C-12(α/β)-(N-) sulfamoyl-phenylamino-14-deoxy-andrographolide derivatives as potent anti-cancer agents.

Science.gov (United States)

Kandanur, Sai Giridhar Sarma; Nanduri, Srinivas; Golakoti, Nageswara Rao

2017-07-01

Andrographolide, the major diterpenoidal constituent of Andrographis paniculata (Acanthaceae) and its derivatives have been reported to possess plethora of biological properties including potent anti-cancer activity. In this work, synthesis and in-vitro anti-cancer evaluation of new C-12-substituted aryl amino 14-deoxy-andrographolide derivatives (III a-f) are reported. The substitutions include various sulfonamide moieties -SO 2 -NH-R 1 . The new derivatives (III a-e) exhibited improved cytotoxicity (GI 50 , TGI and LC 50 ) compared to andrographolide (I) and the corresponding 3,14,19-O-triacetyl andrographolide (II) when evaluated against 60 NCI cell line panel. Compounds III c and III e are found to be non-toxic to normal human dermal fibroblasts (NHDF) cells compared to reference drug THZ-1. Copyright © 2017 Elsevier Ltd. All rights reserved.

Synthesis, biological evaluation, and structure-activity relationship of clonazepam, meclonazepam, and 1,4-benzodiazepine compounds with schistosomicidal activity.

Science.gov (United States)

Menezes, Carla M S; Rivera, Gildardo; Alves, Marina A; do Amaral, Daniel N; Thibaut, Jean Pierre B; Noël, François; Barreiro, Eliezer J; Lima, Lídia M

2012-06-01

The inherent morbidity and mortality caused by schistosomiasis is a serious public health problem in developing countries. Praziquantel is the only drug in therapeutic use, leading to a permanent risk of parasite resistance. In search for new schistosomicidal drugs, meclonazepam, the 3-methyl-derivative of clonazepam, is still considered an interesting lead-candidate because it has a proven schistosomicidal effect in humans but adverse effects on the central nervous system did not allow its clinical use. Herein, the synthesis, in vitro biological evaluation, and molecular modeling of clonazepam, meclonazepam, and analogues are reported to establish the first structure-activity relationship for schistosomicidal benzodiazepines. Our findings indicate that the amide moiety [N(1) H-C(2) (=O)] is the principal pharmacophoric unit of 1,4-benzodiazepine schistosomicidal compounds and that substitution on the amide nitrogen atom (N(1) position) is not tolerated. © 2012 John Wiley & Sons A/S.

Dimeric ligands for GPCRs involved in human reproduction : synthesis and biological evaluation

NARCIS (Netherlands)

Bonger, Kimberly Michelle

2008-01-01

Dimeric ligands for G-protein coupled receptors that are involved in human reproduction, namely the gonadotropin releasing hormone receptor, the luteinizing hormone receptor and the follicle-stimulating hormone receptor, were synthesized and biologically evaluated.

SYNTHESIS, REACTIVITY AND BIOLOGICAL ACTIVITY OF QUINOXALIN-2-ONE DERIVATIVES

OpenAIRE

El Mokhtar Essassi; R. Bouhfid; Y. Kandri Rodi; S. Ferfra; H. Benzeid; Y. Ramli

2010-01-01

Quinoxalines have a great interest in various fields and particularly in chemistry, biology and pharmacology. It enabled the researchers to develop many methods for their preparations and to seek new fields of application. In this review, we’ll expose different methods of synthesis of the quinoxalin-2-one, its reactivity and finally we’ll discuss the various biological activities of its derivatives.

Natural product synthesis at the interface of chemistry and biology

Science.gov (United States)

2014-01-01

Nature has evolved to produce unique and diverse natural products that possess high target affinity and specificity. Natural products have been the richest sources for novel modulators of biomolecular function. Since the chemical synthesis of urea by Wöhler, organic chemists have been intrigued by natural products, leading to the evolution of the field of natural product synthesis over the past two centuries. Natural product synthesis has enabled natural products to play an essential role in drug discovery and chemical biology. With the introduction of novel, innovative concepts and strategies for synthetic efficiency, natural product synthesis in the 21st century is well poised to address the challenges and complexities faced by natural product chemistry and will remain essential to progress in biomedical sciences. PMID:25043880

Novel Carbonyl Analogs of Tamoxifen: Design, Synthesis, and Biological Evaluation

Directory of Open Access Journals (Sweden)

Konstantinos M. Kasiotis

2017-09-01

Full Text Available Aim of this work was to provide tamoxifen analogs with enhanced estrogen receptor (ER binding affinity. Hence, several derivatives were prepared using an efficient triarylethylenes synthetic protocol. The novel compounds bioactivity was evaluated through the determination of their receptor binding affinity and their agonist/antagonist activity against breast cancer tissue using a MCF-7 cell-based assay. Phenyl esters 6a,b and 8a,b exhibited binding affinity to both ERα and ERβ higher than 4-hydroxytamoxifen while compounds 13 and 14 have shown cellular antiestrogenic activity similar to 4-hydroxytamoxifen and the known ER inhibitor ICI182,780. Theoretical calculations and molecular modeling were applied to investigate, support and explain the biological profile of the new compounds. The relevant data indicated an agreement between calculations and demonstrated biological activity allowing to extract useful structure-activity relationships. Results herein underline that modifications of tamoxifen structure still provide molecules with substantial activity, as portrayed in the inhibition of MCF-7 cells proliferation.

Novel Carbonyl Analogues of Tamoxifen: Design, Synthesis, and Biological Evaluation

Science.gov (United States)

Kasiotis, Konstantinos M.; Lambrinidis, George; Fokialakis, Nikolas; Tzanetou, Evangelia N.; Mikros, Emmanuel; Haroutounian, Serkos A.

2017-09-01

Aim of this work was to provide tamoxifen analogues with enhanced estrogen receptor binding affinity. Hence, several derivatives were prepared using an efficient triarylethylenes synthetic protocol. The novel compounds bioactivity was evaluated through the determination of their receptor binding affinity and their agonist/antagonist activity against breast cancer tissue using a MCF-7 cell-based assay. Phenyl esters 6a,b and 8a,b exhibited binding affinity to both ERα and ERβ higher than 4-hydroxytamoxifen while compounds 13 and 14 have shown cellular antiestrogenic activity similar to 4-hydroxytamoxifen and the known estrogen receptor inhibitor ICI182,780. Theoretical calculations and molecular modelling were applied to investigate, support and explain the biological profile of the new compounds. The relevant data indicated an agreement between calculations and demonstrated biological activity allowing to extract useful structure-activity relationships. Results herein underline that modifications of tamoxifen structure still provide molecules with substantial activity, as portrayed in the inhibition of MCF-7 cells proliferation.

SYNTHESIS, REACTIVITY AND BIOLOGICAL ACTIVITY OF QUINOXALIN-2-ONE DERIVATIVES

Directory of Open Access Journals (Sweden)

El Mokhtar Essassi

2010-04-01

Full Text Available Quinoxalines have a great interest in various fields and particularly in chemistry, biology and pharmacology. It enabled the researchers to develop many methods for their preparations and to seek new fields of application. In this review, we’ll expose different methods of synthesis of the quinoxalin-2-one, its reactivity and finally we’ll discuss the various biological activities of its derivatives.

Synthesis and biological evaluation of the progenitor of a new class of cephalosporin analogues, with a particular focus on structure-based computational analysis.

Directory of Open Access Journals (Sweden)

Anna Verdino

Full Text Available We present the synthesis and biological evaluation of the prototype of a new class of cephalosporins, containing an additional isolated beta lactam ring with two phenyl substituents. This new compound is effective against Gram positive microorganisms, with a potency similar to that of ceftriaxone, a cephalosporin widely used in clinics and taken as a reference, and with no cytotoxicity against two different human cell lines, even at a concentration much higher than the minimal inhibitory concentration tested. Additionally, a deep computational analysis has been conducted with the aim of understanding the contribution of its moieties to the binding energy towards several penicillin-binding proteins from both Gram positive and Gram negative bacteria. All these results will help us developing derivatives of this compound with improved chemical and biological properties, such as a broader spectrum of action and/or an increased affinity towards their molecular targets.

Phase-assisted synthesis and DNA unpacking evaluation of biologically inspired metallo nanocomplexes using peptide as unique building block.

Science.gov (United States)

Raman, N; Sudharsan, S

2011-12-01

The goal of nanomaterials' surface modification using a biomaterial is to preserve the materials' bulk properties while modifying only their surface to possess desired recognition and specificity. Here, we have developed a phase-assisted, modified Brust-Schiffrin methodological synthesis of metallo nanocomplexes anchored by a peptide, N,N'-(1,3-propylene)-bis-hippuricamide. The spectral, thermal and morphological characterizations assure the formation of nanocomplexes. Therapeutic behavior of all the nanocomplexes has been well sighted by evaluating their DNA unpacking skills. In addition, we demonstrate their biological inspiration by targeting few bacterial and fungal strains. The in vitro antimicrobial investigation reports that all the nanocomplexes disrupt microbial cell walls/membranes efficiently and inhibit the growth of microbes. These sorts of nanocomplexes synthesized in large quantities and at low cost, deliver versatile biomedical applications, and can be used to treat various diseases which may often cause high mortality. Copyright © 2011 Elsevier Inc. All rights reserved.

Synthesis and biological evaluation of several dephosphonated analogues of CMP-Neu5Ac as inhibitors of GM3-synthase.

Science.gov (United States)

Rota, Paola; Cirillo, Federica; Piccoli, Marco; Gregorio, Antonio; Tettamanti, Guido; Allevi, Pietro; Anastasia, Luigi

2015-10-05

Previous studies demonstrated that reducing the GM3 content in myoblasts increased the cell resistance to hypoxic stress, suggesting that a pharmacological inhibition of the GM3 synthesis could be instrumental for the development of new treatments for ischemic diseases. Herein, the synthesis of several dephosphonated CMP-Neu5Ac congeners and their anti-GM3-synthase activity is reported. Biological activity testes revealed that some inhibitors almost completely blocked the GM3-synthase activity in vitro and reduced the GM3 content in living embryonic kidney 293A cells, eventually activating the epidermal growth factor receptor (EGFR) signaling cascade. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Design, Synthesis, and Biological Evaluation of Vanillin Hydroxamic Acid Derivatives as Novel Peptide Deformylase Inhibitors.

Science.gov (United States)

Gao, Jian; Qiu, Shengzhi; Liang, Li; Hao, Zhixiang; Zhou, Qianqian; Wang, Fanfan; Mou, Jie; Lin, Qisi

2018-01-01

Infectious disease is increasingly hampering human health, which challenge the discovery of new antibacterial target. Peptide deformylase (PDF), a metalloenzyme responsible for catalyzing the removal of the N-formyl group from nascent proteins, was considered as an important target in antibacterial drug discovery. Reported here are the design, synthesis and biological evaluation of vanillin hydroxamic acid derivatives. Analysis of the structure-activity relationships lead to the discovery of compound 8, which exhibits promising antibacterial activity against Escherichia coli, Staphylococcus aureus, Aspergillus oryzae, and Aspergillus foetidus with the MIC value of 0.32 µg/ml, 0.32 µg/ml, 0.16 µg/ml and 0.16 µg/ml, respectively. Furthermore, molecular docking study was applied to elucidate binding interaction between compound 8 and PDF, which indicate that compound 8 not only shares the same binding pocket with actinonin, but also has a similar binding pattern. In silico pharmacokinetic and toxicity prediction studies also suggested that compound 8 has a relatively high drug score of 0.80, and has no risk of toxicity. Compound 8 might represent a promising scaffold for the further development of novel antibacterial drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Synthesis and biological evaluation of flexible and conformationally constrained LpxC inhibitors

DEFF Research Database (Denmark)

Löppenberg, Marius; Müller, Hannes; Pulina, Carla

2013-01-01

, conformationally constrained C-glycosidic as well as open chained hydroxamic acids with a defined stereochemistry were prepared. Diversity was introduced by performing C–C coupling reactions like the Sonogashira and Suzuki cross-coupling reactions. The biological evaluation of the synthesized compounds revealed...

Solid-Phase Synthesis for the Construction of Biologically Interesting Molecules and the Total Synthesis of Trioxacarcin DC-45-A2

DEFF Research Database (Denmark)

Mikkelsen, Remi Jacob Thomsen

. Furthermore a route to another key building block was developed featuring a Stille cross-coupling.Synthesis of Poly-fused Heterocycles. In the search for new biologically active compounds a methodology for the synthesis of polyfused heterocycles was investigated. This led to the development and optimization...

Design, Synthesis and Biological Activity of Novel Reversible Peptidyl FVIIa Inhibitors Rh-Catalyzed Enantioselective Synthesis of Diaryl Amines

DEFF Research Database (Denmark)

Storgaard, Morten

functional group tolerance. Unfortunately, these -aryl tetramic acids were too unreactive and ring opening toward the synthesis of the building block did not succeed. However, -aryl tetramic acids are still interesting compounds due to their potential biological activity. The building block 3.15 (P1......-catalyzed enantioselective synthesis of diaryl amines, which is an important class of compounds (Chapter 4). For example it is found in the third generation anti-histaminic agent levocetirizine. Development of efficient synthetic routes is therefore of considerably interest. The rhodium-catalyzed enantioselective synthesis...

Synthesis and Biological Evaluation of Novel 3-Alkylpyridine Marine Alkaloid Analogs with Promising Anticancer Activity

Directory of Open Access Journals (Sweden)

Alessandra Mirtes Marques Neves Gonçalves

2014-07-01

Full Text Available Cancer continues to be one of the most important health problems worldwide, and the identification of novel drugs and treatments to address this disease is urgent. During recent years, marine organisms have proven to be a promising source of new compounds with action against tumoral cell lines. Here, we describe the synthesis and anticancer activity of eight new 3-alkylpyridine alkaloid (3-APA analogs in four steps and with good yields. The key step for the synthesis of these compounds is a Williamson etherification under phase-transfer conditions. We investigated the influence of the length of the alkyl chain attached to position 3 of the pyridine ring on the cytotoxicity of these compounds. Biological assays demonstrated that compounds with an alkyl chain of ten carbon atoms (4c and 5c were the most active against two tumoral cell lines: RKO-AS-45-1 and HeLa. Micronucleus and TUNEL assays showed that both compounds are mutagenic and induce apoptosis. In addition, Compound 5c altered the cellular actin cytoskeleton in RKO-AS-45-1 cells. The results suggest that Compounds 4c and 5c may be novel prototype anticancer agents.

Green Synthesis of Metallic Nanoparticles via Biological Entities

Directory of Open Access Journals (Sweden)

Monaliben Shah

2015-10-01

Full Text Available Nanotechnology is the creation, manipulation and use of materials at the nanometre size scale (1 to 100 nm. At this size scale there are significant differences in many material properties that are normally not seen in the same materials at larger scales. Although nanoscale materials can be produced using a variety of traditional physical and chemical processes, it is now possible to biologically synthesize materials via environment-friendly green chemistry based techniques. In recent years, the convergence between nanotechnology and biology has created the new field of nanobiotechnology that incorporates the use of biological entities such as actinomycetes algae, bacteria, fungi, viruses, yeasts, and plants in a number of biochemical and biophysical processes. The biological synthesis via nanobiotechnology processes have a significant potential to boost nanoparticles production without the use of harsh, toxic, and expensive chemicals commonly used in conventional physical and chemical processes. The aim of this review is to provide an overview of recent trends in synthesizing nanoparticles via biological entities and their potential applications.

Green Synthesis of Metallic Nanoparticles via Biological Entities

Science.gov (United States)

Shah, Monaliben; Fawcett, Derek; Sharma, Shashi; Tripathy, Suraj Kumar; Poinern, Gérrard Eddy Jai

2015-01-01

Nanotechnology is the creation, manipulation and use of materials at the nanometre size scale (1 to 100 nm). At this size scale there are significant differences in many material properties that are normally not seen in the same materials at larger scales. Although nanoscale materials can be produced using a variety of traditional physical and chemical processes, it is now possible to biologically synthesize materials via environment-friendly green chemistry based techniques. In recent years, the convergence between nanotechnology and biology has created the new field of nanobiotechnology that incorporates the use of biological entities such as actinomycetes algae, bacteria, fungi, viruses, yeasts, and plants in a number of biochemical and biophysical processes. The biological synthesis via nanobiotechnology processes have a significant potential to boost nanoparticles production without the use of harsh, toxic, and expensive chemicals commonly used in conventional physical and chemical processes. The aim of this review is to provide an overview of recent trends in synthesizing nanoparticles via biological entities and their potential applications. PMID:28793638

Cell-free protein synthesis enabled rapid prototyping for metabolic engineering and synthetic biology

Directory of Open Access Journals (Sweden)

Lihong Jiang

2018-06-01

Full Text Available Advances in metabolic engineering and synthetic biology have facilitated the manufacturing of many valuable-added compounds and commodity chemicals using microbial cell factories in the past decade. However, due to complexity of cellular metabolism, the optimization of metabolic pathways for maximal production represents a grand challenge and an unavoidable barrier for metabolic engineering. Recently, cell-free protein synthesis system (CFPS has been emerging as an enabling alternative to address challenges in biomanufacturing. This review summarizes the recent progresses of CFPS in rapid prototyping of biosynthetic pathways and genetic circuits (biosensors to speed up design-build-test (DBT cycles of metabolic engineering and synthetic biology. Keywords: Cell-free protein synthesis, Metabolic pathway optimization, Genetic circuits, Metabolic engineering, Synthetic biology

SYNTHESIS AND IN VITRO ANTIMICROBIAL EVALUATION OF 5 ...

African Journals Online (AJOL)

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creation of molecular diversity and complexity [1-3]. One of the main challenges in medicinal chemistry is the design and synthesis of biologically active molecules. 4H-pyran play an essential role as biologically active compounds and represent an interesting template for medicinal chemistry. Many of these compounds are.

Synthesis and Biological Evaluation of Benzochromenopyrimidinones as Cholinesterase Inhibitors and Potent Antioxidant, Non-Hepatotoxic Agents for Alzheimer’s Disease

Directory of Open Access Journals (Sweden)

Youssef Dgachi

2016-05-01

Full Text Available We report herein the straightforward two-step synthesis and biological assessment of novel racemic benzochromenopyrimidinones as non-hepatotoxic, acetylcholinesterase inhibitors with antioxidative properties. Among them, compound 3Bb displayed a mixed-type inhibition of human acetylcholinesterase (IC50 = 1.28 ± 0.03 μM, good antioxidant activity, and also proved to be non-hepatotoxic on human HepG2 cell line.

Solid-supported synthesis: From pharmacologically relevant heterocycles to biologically active surfaces

DEFF Research Database (Denmark)

Komnatnyy, Vitaly V.

for solid-phase synthesis, methods for on - and off-bead screening of combinatorial libraries and their applic ation to various biological targets. The first part of the thesis is dedicated to the development of methodology for the synthesis of structurally diverse heterocyclic scaffolds via N...... methods for the controlled organo-functionalization of titanium, one of the most prominent materials in medicinal device industry, have been suggested . Initial acidic and oxidative treatment s of the metal surface genera te reactive hydroxyl moieties , which are subsequently modified with synthetically...... versatile amine -containing reagents. Subsequent applications in antimicrobial peptide synthesis, metal -catalysis, release from the surface, and polymer grafti ng, are also presented....

Synthesis, Molecular Modelling and Biological Evaluation of Novel Heterodimeric, Multiple Ligands Targeting Cholinesterases and Amyloid Beta

Directory of Open Access Journals (Sweden)

Michalina Hebda

2016-03-01

Full Text Available Cholinesterases and amyloid beta are one of the major biological targets in the search for a new and efficacious treatment of Alzheimer’s disease. The study describes synthesis and pharmacological evaluation of new compounds designed as dual binding site acetylcholinesterase inhibitors. Among the synthesized compounds, two deserve special attention—compounds 42 and 13. The former is a saccharin derivative and the most potent and selective acetylcholinesterase inhibitor (EeAChE IC50 = 70 nM. Isoindoline-1,3-dione derivative 13 displays balanced inhibitory potency against acetyl- and butyrylcholinesterase (BuChE (EeAChE IC50 = 0.76 μM, EqBuChE IC50 = 0.618 μM, and it inhibits amyloid beta aggregation (35.8% at 10 μM. Kinetic studies show that the developed compounds act as mixed or non-competitive acetylcholinesterase inhibitors. According to molecular modelling studies, they are able to interact with both catalytic and peripheral active sites of the acetylcholinesterase. Their ability to cross the blood-brain barrier (BBB was confirmed in vitro in the parallel artificial membrane permeability BBB assay. These compounds can be used as a solid starting point for further development of novel multifunctional ligands as potential anti-Alzheimer’s agents.

Synthesis, characterization, and in vitro biological evaluation of highly stable diversely functionalized superparamagnetic iron oxide nanoparticles

International Nuclear Information System (INIS)

Bhattacharya, Dipsikha; Sahu, Sumanta K.; Banerjee, Indranil; Das, Manasmita; Mishra, Debashish; Maiti, Tapas K.; Pramanik, Panchanan

2011-01-01

In this article, we report the design and synthesis of a series of well-dispersed superparamagnetic iron oxide nanoparticles (SPIONs) using chitosan as a surface modifying agent to develop a potential T 2 contrast probe for magnetic resonance imaging (MRI). The amine, carboxyl, hydroxyl, and thiol functionalities were introduced on chitosan-coated magnetic probe via simple reactions with small reactive organic molecules to afford a series of biofunctionalized nanoparticles. Physico-chemical characterizations of these functionalized nanoparticles were performed by TEM, XRD, DLS, FTIR, and VSM. The colloidal stability of these functionalized iron oxide nanoparticles was investigated in presence of phosphate buffer saline, high salt concentrations and different cell media for 1 week. MRI analysis of human cervical carcinoma (HeLa) cell lines treated with nanoparticles elucidated that the amine-functionalized nanoparticles exhibited higher amount of signal darkening and lower T 2 relaxation in comparison to the others. The cellular internalization efficacy of these functionalized SPIONs was also investigated with HeLa cancer cell line by magnetically activated cell sorting (MACS) and fluorescence microscopy and results established selectively higher internalization efficacy of amine-functionalized nanoparticles to cancer cells. These positive attributes demonstrated that these nanoconjugates can be used as a promising platform for further in vitro and in vivo biological evaluations.

Synthesis and biological evaluation of novel gramicidin s analogues

NARCIS (Netherlands)

Tuin, A.W.; Palachanis, D.K.; Buizert, A.; Grotenbreg, G.M.; Spalburg, E.; Neeling, A.J. de; Mars-Groenendijk, R.H.; Noort, D.; Marel, G.A. van der; Overkleeft, H.S.; Overhand, M.

2009-01-01

The synthesis of three new analogues of the cyclic cationic antimicrobial peptide Gramicidin S is described. These derivatives contain a modified turn region in which the DPhe-Pro motif has been replaced by a constrained furanoid sugar amino acid or a flexible linear aminoethoxy acetic acid moiety.

Synthesis of novel (-)-epicatechin derivatives as potential endothelial GPER agonists: Evaluation of biological effects.

Science.gov (United States)

Sarmiento, Viviana; Ramirez-Sanchez, Israel; Moreno-Ulloa, Aldo; Romero-Perez, Diego; Chávez, Daniel; Ortiz, Miguel; Najera, Nayelli; Correa-Basurto, Jose; Villarreal, Francisco; Ceballos, Guillermo

2018-02-15

To potentially identify proteins that interact (i.e. bind) and may contribute to mediate (-)-epicatechin (Epi) responses in endothelial cells we implemented the following strategy: 1) synthesis of novel Epi derivatives amenable to affinity column use, 2) in silico molecular docking studies of the novel derivatives on G protein-coupled estrogen receptor (GPER), 3) biological assessment of the derivatives on NO production, 4) implementation of an immobilized Epi derivative affinity column and, 5) affinity column based isolation of Epi interacting proteins from endothelial cell protein extracts. For these purposes, the Epi phenol and C3 hydroxyl groups were chemically modified with propargyl or mesyl groups. Docking studies of the novel Epi derivatives on GPER conformers at 14 ns and 70 ns demostrated favorable thermodynamic interactions reaching the binding site. Cultures of bovine coronary artery endothelial cells (BCAEC) treated with Epi derivatives stimulated NO production via Ser1179 phosphorylation of eNOS, effects that were attenuated by the use of the GPER blocker, G15. Epi derivative affinity columns yielded multiple proteins from BCAEC. Proteins were electrophoretically separated and inmmunoblotting analysis revealed GPER as an Epi derivative binding protein. Altogether, these results validate the proposed strategy to potentially isolate and identify novel Epi receptors that may account for its biological activity. Copyright © 2018 Elsevier Ltd. All rights reserved.

PASS-predicted design, synthesis and biological evaluation of cyclic nitrones as nootropics.

Science.gov (United States)

Marwaha, Alka; Goel, R K; Mahajan, Mohinder P

2007-09-15

Out of 400 virtually designed imidazoline N-oxides, five cyclic nitrones were selected on the basis of PASS prediction as potent nootropics and were evaluated for their biological activities in albino mice. The selected N-alkyl and aryl-substituted nitrones were found to be excellent nootropics. A series of lead compounds acting as cognition enhancers have been provided, which can be further exploited in search of such New Chemical Entities (NCEs).

Synthesis of Biologically Active Natural Component 4-Hydroxyderricin Through Water-Accelerated [3,3]-Sigmatropic Rearrangement

Energy Technology Data Exchange (ETDEWEB)

Kim, Sijun; Lee, Jaejun; Yoon, Hyunho; Jun, Jonggab [Hallym Univ., Chuncheon (Korea, Republic of)

2013-09-15

We report herein the practical and effective total synthesis of biologically active 4-hydroxyderricin, a poly-phenolic chalcone compound containing m-prenyl group at ring A. The key steps of the synthesis are Claisen-Schmidt condensation of the the two phenolic units 17 and 18 to chalcone 19 and the water-accelerated [3,3]-sigma-tropic rearrangement of 1,1-dimethyl-2-propenyl aryl ether 20 to introduce the m-prenyl unit in 4-hydroxyderricin. Two types of polyphenolic chalcones, 4-hydroxyderricin (1) and xanthoangelol (2), are especially rich in the plant, and the 4-hydroxyderricin exhibited the major responsibility for the various biological activities. Sugamoto reported the synthesis of 4-hydroxy-derricin via [1,3]-sigmatropic rearrangement of chalcone ether using montmorillonite K10 which showed relatively low rearrangement yield (Scheme 1), and this is the only reported total synthesis of 1 as far as we know.

Total synthesis and biological investigation of (-)-promysalin.

Science.gov (United States)

Steele, Andrew D; Knouse, Kyle W; Keohane, Colleen E; Wuest, William M

2015-06-17

Compounds that specifically target pathogenic bacteria are greatly needed, and identifying the method by which they act would provide new avenues of treatment. Herein we report the concise, high-yielding total synthesis (eight steps, 35% yield) of promysalin, a natural product that displays antivirulence phenotypes against pathogenic bacteria. Guided by bioinformatics, four diastereomers were synthesized, and the relative and absolute stereochemistries were confirmed by spectral and biological analysis. Finally, we show for the first time that promysalin displays two antivirulence phenotypes: the dispersion of mature biofilms and the inhibition of pyoverdine production, hinting at a unique pathogenic-specific mechanism of action.

Using Simple Manipulatives to Improve Student Comprehension of a Complex Biological Process: Protein Synthesis

Science.gov (United States)

Guzman, Karen; Bartlett, John

2012-01-01

Biological systems and living processes involve a complex interplay of biochemicals and macromolecular structures that can be challenging for undergraduate students to comprehend and, thus, misconceptions abound. Protein synthesis, or translation, is an example of a biological process for which students often hold many misconceptions. This article…

Synthesis and Biological Evaluation of Resveratrol Derivatives as Melanogenesis Inhibitors

Directory of Open Access Journals (Sweden)

Qing Liu

2015-09-01

Full Text Available Resveratrol (1, a naturally occurring stilbene compound, has been suggested as a potential whitening agent with strong inhibitory activity on melanin synthesis. However, the use of resveratrol in cosmetics has been limited due to its chemical instability and poor bioavailability. Therefore, resveratrol derivatives were prepared to improve bioavailability and anti-melanogenesis activity. Nine resveratrol derivatives including five alkyl ether derivatives with C2H5, C4H9, C5H11, C6H13, and C8H17 (2a–2e and four ester derivatives with CH3, CH=C(CH32, CH(C2H5C4H9, C7H15 (3a–3d were newly synthesized and their effect on melanin synthesis were assessed. All the synthetic derivatives efficiently reduced the melanin content in α-MSH stimulated B16F10 melanoma cells. Further investigation showed that the inhibitory effect of 2a on melanin synthesis was achieved not by the inhibition of tyrosinase activity but by the inhibition of melanogenic enzyme expressions such as tyrosinase and tyrosinase-related protein (TRP-1. Our synthetic resveratrol derivatives have more lipophilic properties than resveratrol by the addition of alkyl or acyl chains to free hydroxyl moiety of resveratrol; thus, they are expected to show better bioavailability in skin application. Therefore, we suggest that our synthetic resveratrol derivatives might be promising candidates for better practical application to skin-whitening cosmetics.

Synthesis and in vitro biological evaluation of new pyrazole chalcones and heterocyclic diamides as potential anticancer agents

Directory of Open Access Journals (Sweden)

Sankappa Rai U.

2015-05-01

Full Text Available Synthesis and characterization of new heterocyclic pyrazole chalcones (4a–e and diamide (6a–e derivatives are described. Pyrazole chalcones were synthesized by the reaction of pyrazole aldehydes and suitable aromatic ketones. Diamides were synthesized by the reaction of phthalic acid and amines. Newly synthesized compounds were characterized by spectral studies and their biological activity was assessed in vitro using MCF-7 (human breast adenocarcinoma and HeLa (human cervical tumor cells cell lines. Few of the synthesized molecules inhibited the growth of the human breast cancer cell lines and human cervical tumor cell lines at low micromolar to nanomolar concentrations.

Synthesis and initial biological evaluation of a novel Tc-99m radioligand as a potential agent for 5-HT1A receptor imaging

Energy Technology Data Exchange (ETDEWEB)

Abdelounis, Najoua Mejri; Saied, Nadia Malek; Essouissi, Imen; Guizani, Sihem; Saidi, Mouldi [CNSTN, Sidi Thabet (Tunisia). Research Unit of Medical, Agricultural and Environmental Use of Nuclear Applications

2014-09-01

The synthesis, characterization and biological evaluation of N-Tolueneferrocenecarboxamide labeled with technetium-99m ({sup 99m}Tc-TTCC) is reported. Biological studies in Wistar rats showed the ability of {sup 99m}Tc-TPCC to cross the intact blood-brain barrier. In vivo biodistribution indicated that this complex had good brain uptake (1.32%ID/g at 5 min and 0.64%ID/g at 60 min) and good retention (about 50% of the activity was retained in the brain at 60 min post-injection). Regional brain distribution study showed that hippocampus, where the 5-HT1A receptor density is high, had the highest uptake (0.73%ID/g at 5 min p.i.) and the cerebellum, where the 5-HT1A receptor density is low, had the lowest uptake (0.12%ID/gID/g at 5 min p.i.). After blocking with 8-hydroxy-2-(dipropylamino) tetralin, the uptake of hippocampus was decreased significantly from 0.73%ID/g to 0.20%ID/g at 5 min p.i., while the cerebellum had no significant decrease. This result indicates that 99mTc complex has specific binding to 5-HT1A receptor. (orig.)

Simultaneous biological nutrient removal: evaluation of autotrophic denitrification, heterotrophic nitrification, and biological phosphorus removal in full-scale systems.

Science.gov (United States)

Littleton, Helen X; Daigger, Glen T; Strom, Peter F; Cowan, Robert A

2003-01-01

Simultaneous biological nutrient removal (SBNR) is the biological removal of nitrogen and phosphorus in excess of that required for biomass synthesis in a biological wastewater treatment system without defined anaerobic or anoxic zones. Evidence is growing that significant SBNR can occur in many systems, including the aerobic zone of systems already configured for biological nutrient removal. Although SBNR systems offer several potential advantages, they cannot be fully realized until the mechanisms responsible for SBNR are better understood. Consequently, a research program was initiated with the basic hypothesis that three mechanisms might be responsible for SBNR: the reactor macroenvironment, the floc microenvironment, and novel microorganisms. Previously, the nutrient removal capabilities of seven full-scale, staged, closed-loop bioreactors known as Orbal oxidation ditches were evaluated. Chemical analysis and microbiological observations suggested that SBNR occurred in these systems. Three of these plants were further examined in this research to evaluate the importance of novel microorganisms, especially for nitrogen removal. A screening tool was developed to determine the relative significance of the activities of microorganisms capable of autotrophic denitrification and heterotrophic nitrification-aerobic denitrification in biological nutrient removal systems. The results indicated that novel microorganisms were not substantial contributors to SBNR in the plants studied. Phosphorus metabolism (anaerobic release, aerobic uptake) was also tested in one of the plants. Activity within the mixed liquor that was consistent with current theories for phosphorus-accumulating organisms (PAOs) was observed. Along with other observations, this suggests the presence of PAOs in the facilities studied.

Severe Acute Respiratory Syndrome-Coronavirus Papain-Like Novel Protease Inhibitors: Design, Synthesis, Protein-Ligand X-ray Structure and Biological Evaluation

Energy Technology Data Exchange (ETDEWEB)

Ghosh, Arun K.; Takayama, Jun; Rao, Kalapala Venkateswar; Ratia, Kiira; Chaudhuri, Rima; Mulhearn, Debbie C.; Lee, Hyun; Nichols, Daniel B.; Baliji, Surendranath; Baker, Susan C.; Johnson, Michael E.; Mesecar, Andrew D. (Purdue); (UC); (UIC)

2012-02-21

The design, synthesis, X-ray crystal structure, molecular modeling, and biological evaluation of a series of new generation SARS-CoV PLpro inhibitors are described. A new lead compound 3 (6577871) was identified via high-throughput screening of a diverse chemical library. Subsequently, we carried out lead optimization and structure-activity studies to provide a series of improved inhibitors that show potent PLpro inhibition and antiviral activity against SARS-CoV infected Vero E6 cells. Interestingly, the (S)-Me inhibitor 15h (enzyme IC{sub 50} = 0.56 {mu}M; antiviral EC{sub 50} = 9.1 {mu}M) and the corresponding (R)-Me 15g (IC{sub 50} = 0.32 {mu}M; antiviral EC{sub 50} = 9.1 {mu}M) are the most potent compounds in this series, with nearly equivalent enzymatic inhibition and antiviral activity. A protein-ligand X-ray structure of 15g-bound SARS-CoV PLpro and a corresponding model of 15h docked to PLpro provide intriguing molecular insight into the ligand-binding site interactions.

Biological upgrading of coal-derived synthesis gas: Final report

Energy Technology Data Exchange (ETDEWEB)

Barik, S.; Johnson, E.R.; Ko, C.W.; Clausen, E.C.; Gaddy, J.L.

1986-10-01

The technical feasibility of the biological conversion of coal synthesis gas to methane has been demonstrated in the University of Arkansas laboratories. Cultures of microorganisms have been developed which achieve total conversion in the water gas shift and methanation reactions in either mixed or pure cultures. These cultures carry out these conversions at ordinary temperatures and pressures, without sulfur toxicity. Several microorganisms have been identified as having commercial potential for producing methane. These include a mixed culture of unidentified bacteria; P. productus which produces acetate, a methane precursor; and Methanothrix sp., which produces methane from acetate. These cultures have been used in mixed reactors and immobilized cell reactors to achieve total CO and H/sub 2/ conversion in a retention time of less than two hours, quite good for a biological reactor. Preliminary economic projections indicate that a biological methanation plant with a size of 5 x 10/sup 10/ Btu/day can be economically attractive. 42 refs., 26 figs., 86 tabs.

Microfluidic Synthesis and Biological Evaluation of Photothermal Biodegradable Copper Sulfide Nanoparticles.

Science.gov (United States)

Ortiz de Solorzano, Isabel; Prieto, Martín; Mendoza, Gracia; Alejo, Teresa; Irusta, Silvia; Sebastian, Victor; Arruebo, Manuel

2016-08-24

The continuous synthesis of biodegradable photothermal copper sulfide nanoparticles has been carried out with the aid of a microfluidic platform. A comparative physicochemical characterization of the resulting products from the microreactor and from a conventional batch reactor has been performed. The microreactor is able to operate in a continuous manner and with a 4-fold reduction in the synthesis times compared to that of the conventional batch reactor producing nanoparticles with the same physicochemical requirements. Biodegradation subproducts obtained under simulated physiological conditions have been identified, and a complete cytotoxicological analysis on different cell lines was performed. The photothermal effect of those nanomaterials has been demonstrated in vitro as well as their ability to generate reactive oxygen species.

Synthesis and biological evaluation of porphyrin-polyamine conjugates as potential agents in photodynamic therapy

International Nuclear Information System (INIS)

Lamarche, Francois

2004-01-01

The synthesis of photosensitizers that specifically recognize tumoral cells constitutes a challenging step in the field of photodynamic therapy. To this end, we designed a new class of porphyrins linked to natural polyamines (spermidine, spermine). As a first step, we synthesized para and ortho-carboxy-propyl-oxy-phenyl-tritolyl-porphyrins bearing spermidine or spermine. Then, we designed two precursors, N4-aminobutyl-spermidine-Boc2 and N4-aminobutyl-spermine-Boc3. These derivatives have been fixed on carboxy-porphyrins, protoporphyrin IX and chlorin e6. These new compounds have been characterized by MALDI spectrometry, UV-Visible and 1 H NMR spectroscopy. They have been found to produce singlet oxygen. Biological activity study of these photosensitizers has been realized on K562 cell line, irradiated with fluorescent bulbs. In vitro tests of these porphyrins have shown their photo-cytotoxic activity and protoporphyrins-polyamines have been able to trigger early apoptotic events. Finally, preliminary results obtained with chlorin e6-polyamines, irradiated with red light, seem to show that these structures are good candidates for an application in PDT. (author) [fr

Cephalostatin analogues--synthesis and biological activity.

Science.gov (United States)

Flessner, Timo; Jautelat, Rolf; Scholz, Ulrich; Winterfeldt, Ekkehard

2004-01-01

discussion on this topic: see Chapter 3). In line with this are the observations that 14,15-alpha-epoxides do substantially decrease activity (cephalostatins 14 and 15) while a 14,15-beta-epoxide does not decrease activity (cephalostatin 4). Also in line with the "curvature theory" is the fact that ritterazine B (14-beta-hydrogen) is even more potent than ritterazine G (14,15-double bond). Therefore it is not clear if--at least one--14,15-double bond is essential for high activity. The synthesis and biological evaluation of completely 14-beta-saturated analogues (like 14'-beta-hydrogen ritterazine B) could answer this question. Synthesis of the partially saturated analogues 14' alpha-cephalostatin 1 1c and 7-deoxy-14' alpha-ritterazine B 2a showed that the stronger the divergence of conformation implied by the saturation is, the higher is the loss of activity, thus underlining the "curvature hypothesis". Synthesis showed, that analogues possessing the 14,15-double bond(s) are substantially better soluble, e.g. 26. Furthermore, the D-Ring area turned out to be sensitive for modifications, since substantially differing analogues, like 162, 163, and 164 were completely inactive. At least one 17-hydroxy group is part of all highly active cephalostatins/ritterazines. Loss of one out of two 17-hydroxy groups does not decrease activity (compare ritterazine K and L) but of the second 17-hydroxy groups (along with the 7-hydroxy group) as seen in the ritterazine series (compare ritterazines A/T and B/Y) leads to a significant decrease in activity. Increased activity of 17-ether analogues 178 and 179 points into the same direction All highly active cephalostatins and ritterazines are substantially asymmetric. Cephalostatins and ritterazines that are symmetric--either consisting of two polar units (cephalostatin 12 and ritterazine K) or two unpolar units (ritterazine N and ritterazine R)--or almost symmetric (cephalostatin 13 and ritterazine J, L, M, O, S) show substantially diminished

Design, Synthesis and Biological Evaluation of Quorum Sensing Modulators

DEFF Research Database (Denmark)

Hansen, Mette Reimert

to intercept the communication system by synthetic non-native ligands and thereby lower the pathogenesis and antibiotic tolerance of a bacterial biofilm. To identify new ligands with quorum sensing modulating activities, three types of AHL analogs were synthesized using different synthetic strategies....... Overall, 17 compounds were identified as quorum sensing activators with EC50 values in the low micromolar range. Two build/couple/pair strategies for the synthesis of structurally diverse small molecules are presented. In the first strategy, the Petasis 3-component reaction (Petasis 3-CR) of hydrazides...

Synthesis of molecules of biological interest labelled with high specific activity tritium

International Nuclear Information System (INIS)

Petillot, Yves

1975-01-01

Labelled molecules are artificial organic compounds possessing one or several radioactive or steady isotopic atoms. Using tritium to label molecules presents several benefits: a raw material easy to obtain with a high purity and at reasonable cost; synthesised labelled molecules displaying high specific activities very interesting in molecular biology; high resolution of radiographies; relatively simple and quick introduction of tritium atoms in complex molecules. Thus, this report for graduation in organic chemistry addresses the synthesis and study of new labelled molecules which belong to families of organic compounds which have fundamental activities in biology: uridine 3 H-5,6 and thymidine 3 H-methyl which are nucleotides which intervene under the form of phosphates in the synthesis of nucleic acids, oestradiol 3 H-2,4,6,7 which is a powerful estrogenic hormone which naturally secreted by the ovary; and noradrenaline 3 H-1,1' and dopamine 3 H-1,2 which are usually secreted by adrenal medulla and have multiple actions on the nervous system

Biological Synthesis of Silver Nanoparticles by Cell-Free Extract of Spirulina platensis

Directory of Open Access Journals (Sweden)

Gaurav Sharma

2015-01-01

Full Text Available The present study explores biological synthesis of silver nanoparticles (AgNPs using the cell-free extract of Spirulina platensis. Biosynthesised AgNPs were characterised by UV-Vis spectroscopy, SEM, TEM, and FTIR analysis and finally evaluated for antibacterial activity. Extracellular synthesis using aqueous extract of S. platensis showed the formation of well scattered, highly stable, spherical AgNPs with an average size of 30–50 nm. The size and morphology of the nanoparticles were confirmed by SEM and TEM analysis. FTIR and UV-Vis spectra showed that biomolecules, proteins and peptides, are mainly responsible for the formation and stabilisation of AgNPs. Furthermore, the synthesised nanoparticles exhibited high antibacterial activity against pathogenic Gram-negative, that is, Escherichia coli, MTCC-9721; Proteus vulgaris, MTCC-7299; Klebsiella pneumoniae, MTCC-9751, and Gram-positive, that is, Staphylococcus aureus, MTCC-9542; S. epidermidis, MTCC-2639; Bacillus cereus, MTCC-9017, bacteria. The AgNPs had shown maximum zone of inhibition (ZOI that is 31.3±1.11 in P. vulgaris. Use of such a microalgal system provides a simple, cost-effective alternative template for the biosynthesis of nanomaterials of silver in a large scale that could be of great use in biomedical applications.

Synthesis and biological activity of the novel indanedione anticoagulant rodenticides containing fluorine.

Science.gov (United States)

Chen, Feng; Liu, Liping; Bai, Zengguo; Zhang, Tianhua; Zhao, Keke

2017-01-02

Here, 3 fluorinated intermediates of drug were synthesized: (M1), (M2), (M3). Three new anticoagulant rodenticides were designed which were based on 4-hydroxycoumarin or 1,3-indandione, added acute toxicity groups containing fluorine. The structures of synthesized compounds were analyzed and proved by FT-IR spectroscopy and 1 H nuclear magnetic resonance ( 1 H-NMR). The compounds were also evaluated for their anticoagulant and acute biologic activity. In addition, both the acute orally toxicity and the feeding indexes of R 1 and R 2 were tested. The result of the experiment proved that the new synthesis of 1, 3 - indan diketone for maternal new anticoagulant rodenticide can replace the current 4 - hydroxyl coumarin as the mother of the second generation anticoagulant rodenticide and 1, 3 - indan diketone for maternal new anticoagulant rodenticides will have a good development prospect.

Assessment of PVA/silver nanocomposite hydrogel patch as antimicrobial dressing scaffold: Synthesis, characterization and biological evaluation

International Nuclear Information System (INIS)

Bhowmick, Sirsendu; Koul, Veena

2016-01-01

A novel, elastic, non-adhesive and antimicrobial hydrogel PVA scaffold (loaded with AgNPs) synthesized using freeze-thaw method has been characterized in this study. The direct visualization of the as synthesized (one-pot green synthesis methodology) AgNPs using TEM shows particle size in the range of 7 ± 3 nm. The minimum inhibitory concentration (MIC) of AgNPs for Staphylococcus aureus and Escherichia coli was estimated to be 7.81 μg/mL, whereas for Pseudomonas aeruginosa (gram negative) it was around 3.90 μg/mL. The antimicrobial efficacy of AgNPs was further studied by protein leakage, ROS and LDH activity assay. The quantitative elemental analysis of silver was calculated before and after release in phosphate buffer (pH-7.4) by atomic absorption spectroscopy. The antimicrobial efficacy of the scaffold was retained even after 96 h of release of AgNPs which suggests that the scaffold can be used as a reservoir for AgNPs to maintain a moist and sterile environment for a long period of time. - Highlights: • Green synthesis of AgNPs and evaluation of its antimicrobial efficacy • Synthesis of PVA hydrogel by freeze thaw technique • Antimicrobial activity of AgNPs loaded PVA hydrogel by zone of inhibition • Release kinetics of AgNPs from hydrogel by atomic absorption spectroscopy

Assessment of PVA/silver nanocomposite hydrogel patch as antimicrobial dressing scaffold: Synthesis, characterization and biological evaluation

Energy Technology Data Exchange (ETDEWEB)

Bhowmick, Sirsendu; Koul, Veena, E-mail: veenak@iitd.ac.in

2016-02-01

A novel, elastic, non-adhesive and antimicrobial hydrogel PVA scaffold (loaded with AgNPs) synthesized using freeze-thaw method has been characterized in this study. The direct visualization of the as synthesized (one-pot green synthesis methodology) AgNPs using TEM shows particle size in the range of 7 ± 3 nm. The minimum inhibitory concentration (MIC) of AgNPs for Staphylococcus aureus and Escherichia coli was estimated to be 7.81 μg/mL, whereas for Pseudomonas aeruginosa (gram negative) it was around 3.90 μg/mL. The antimicrobial efficacy of AgNPs was further studied by protein leakage, ROS and LDH activity assay. The quantitative elemental analysis of silver was calculated before and after release in phosphate buffer (pH-7.4) by atomic absorption spectroscopy. The antimicrobial efficacy of the scaffold was retained even after 96 h of release of AgNPs which suggests that the scaffold can be used as a reservoir for AgNPs to maintain a moist and sterile environment for a long period of time. - Highlights: • Green synthesis of AgNPs and evaluation of its antimicrobial efficacy • Synthesis of PVA hydrogel by freeze thaw technique • Antimicrobial activity of AgNPs loaded PVA hydrogel by zone of inhibition • Release kinetics of AgNPs from hydrogel by atomic absorption spectroscopy.

Synthesis and biological evaluation of 3,6-dialkylsubstituted-[1,2,4 ...

Indian Academy of Sciences (India)

VIJAYENDAR VENEPALLY

2018-02-16

Feb 16, 2018 ... A series of 3,6-dialkyl-[1,2,4] triazolo[3,4-b][1,3,4]thiadiazole (10) analogues were ... Cytotoxicity data revealed that most of the tested compounds revealed cytotoxic ...... jary B 2003 Synthesis characterization and anticancer.

Synthesis, formulation of nucleo-equipment and biological studies of the 99m Tc-MAG3

International Nuclear Information System (INIS)

Reyes H, L.; Lezama C, J.; Ferro F, G.

1991-10-01

Technetium-99m-mercaptoacetyl glycylglycylglycine ( 99m Tc-MAG 3 ) is introduced to replace o-iodohippurate (OIH) for renal function studies. In this paper we present the synthesis, labelling and biological evaluation of 99m Tc- MAG 3 prepared in our laboratory. The precursor s-benzoyl-mercaptoacetyl glycyl glycylglycine (Bz-MAG 3 ) was synthesized by condensation of glycylglycylglycine with chloroacetyl chloride to obtain chloroacetyl glycylglycylglycine and this product was condensate with sodium thiobenzoate. The Bz-MAG 3 was characterized by IR and NMR. The labelling with 99m Tc was carried out at pH 9.0 using stannous chloride as a reducing agent with heating to boiling for 15 min. The benzoyl group is lost in this step, forming 99m Tc-MAG 3 complex with radiochemical purity of 99%. The biodistribution properties were evaluated in mice and a rapid renal extraction was apparent at the 10 minutes value (51.65% of the injected dose). The radiotracer was administered to 5 patients showing a good biological behavior. Based on these results, the 99m Tc-MAG 3 is expected to have widespread clinical utility in Mexico. (Author)

Quaternary Alkylammonium Conjugates of Steroids: Synthesis, Molecular Structure, and Biological Studies

Directory of Open Access Journals (Sweden)

Bogumił Brycki

2015-11-01

Full Text Available The methods of synthesis as well as physical, spectroscopic (1H-NMR, 13C-NMR, and FT-IR, ESI-MS, and biological properties of quaternary and dimeric quaternary alkylammonium conjugates of steroids are presented. The results were contrasted with theoretical calculations (PM5 methods and potential pharmacological properties (PASS. Alkylammonium sterols exhibit a broad spectrum of antimicrobial activity comparable to squalamine.

Synthesis and biological evaluation of biaryl analogs of antitubulin compounds

Energy Technology Data Exchange (ETDEWEB)

Tozatti, Camila Santos Suniga; Khodyuk, Rejane Goncalves Diniz; Silva, Adriano Olimpio da; Santos, Edson dos Anjos dos; Amaral, Marcos Serrou do; Lima, Denis Pires de, E-mail: denis.lima@ufms.br [Centro de Ciencias Exatas e Tecnologia, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS (Brazil); Hamel, Ernest [Screening Technologies Branch, Division of Cancer Treatment and Diagnosis, National Cancer Institute at Frederick, MD (United States)

2012-07-01

This paper reports the synthesis of methanones and esters bearing different substitution patterns as spacer groups between aromatic rings. This series of compounds can be considered phenstatin analogs. Two of the newly synthesized compounds, 5a and 5c, strongly inhibited tubulin polymerization and the binding of [{sup 3}H] colchicine to tubulin, suggesting that, akin to phenstatin and combretastatin A-4, they can bind to tubulin at the colchicine site. (author)

Synthesis and biological evaluation of new salicylate macrolactones from anacardic acids

International Nuclear Information System (INIS)

Logrado, Lucio P.L.; Santos, Maria Lucilia dos; Silveira, Damaris; Romeiro, Luiz A.S.; Moraes, Manoel O. de; Cavalcanti, Bruno C.; Costa-Lotufo, Leticia V.; Pessoa, Claudia do O

2005-01-01

In connection with our ongoing investigation in the search for new bioactive compounds using non-isoprenoid phenolic lipids from Anacardium occidentale as starting material, we describe the synthesis and cytotoxicity screening of some novel salicylate macrolactones prepared from anacardic acids, the major constituents of natural cashew nut-shell liquid (CNSL). (author)

SYNTHESIS, CHARACTERIZATION AND ANTIBACTERIAL ...

African Journals Online (AJOL)

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In the present study, synthesis, and biological evaluation of some novel ... Then slowly cooled and resultant mixture was basified with aqueous sodium hydroxide ... mol), anhydrous potassium carbonate (5.52 g, 0.04 mol) in acetone (25 mL), ...

Novel Penicillin-Type Analogues Bearing a Variable Substituted 2-Azetidinone Ring at Position 6: Synthesis and Biological Evaluation

Directory of Open Access Journals (Sweden)

Margherita De Rosa

2015-12-01

Full Text Available The synthesis and the biological activity of novel semi-synthetic β-lactam compounds containing an azetidinone moiety joined to the amino-nitrogen of the (+-6-aminopenicillanic acid (6-APA as new antibacterial agents is reported. The synthesized compounds were screened for their in vitro antimicrobial activity against a panel of Gram positive and Gram negative pathogens and environmental bacteria. Tested compounds displayed good antimicrobial activity against all tested Gram positive bacteria and for Staphylococcus aureus and Staphylococcus epidermidis antimicrobial activity resulted higher than that of the reference antibiotic. Additionally, in vitro cytotoxic screening was also carried out indicating that the compounds do not cause a cell vitality reduction effective at concentration next to and above those shown to be antimicrobial.

Novel Penicillin-Type Analogues Bearing a Variable Substituted 2-Azetidinone Ring at Position 6: Synthesis and Biological Evaluation.

Science.gov (United States)

De Rosa, Margherita; Vigliotta, Giovanni; Palma, Giuseppe; Saturnino, Carmela; Soriente, Annunziata

2015-12-10

The synthesis and the biological activity of novel semi-synthetic β-lactam compounds containing an azetidinone moiety joined to the amino-nitrogen of the (+)-6-aminopenicillanic acid (6-APA) as new antibacterial agents is reported. The synthesized compounds were screened for their in vitro antimicrobial activity against a panel of Gram positive and Gram negative pathogens and environmental bacteria. Tested compounds displayed good antimicrobial activity against all tested Gram positive bacteria and for Staphylococcus aureus and Staphylococcus epidermidis antimicrobial activity resulted higher than that of the reference antibiotic. Additionally, in vitro cytotoxic screening was also carried out indicating that the compounds do not cause a cell vitality reduction effective at concentration next to and above those shown to be antimicrobial.

Synthesis and evaluation of [[sup 18]F]fluoroprogestins and [[sup 18]F]fluorometoprolol

Energy Technology Data Exchange (ETDEWEB)

De Groot, T J

1993-05-01

The author investigated if specific radioactively labelled compounds could be applied to gain insight into particular psychic diseases, f.e. Parkinson's disease and schizophrenia, by means of Positron Emission Tomography (PET). No appropriate compounds were found. In this thesis the syntheses of fluorine-18 labelled progestins and [beta][sub 1]-adrenergic ligands are described. Three approaches towards [[sup 18]F]fluorination are investigated. The first method concerns direct S[sub N]2-substitution, the second approach is the opening of an epoxide, and the third approach is [[sup 18]F]fluoroalkylation. The positron emitting radionuclide fluorine-18 was used because of its relatively long decay time and the possibility to produce it in high yields and with high specific activity. The target systems which were applied for the production of fluorine-18 are described in chapter two. Important chemical and physical aspects of [[sup 18]F]fluoride are reviewed in the same chapter. In chapter three the synthesis of 21-[[sup 18]F]fluorinated progestins is discussed. The synthesis of four 21-[[sup 18]F]fluoroprogesterone derivatives is described and the results of an in vivo evaluation of two of these ligands are discussed. Possible routes leading to 6[alpha]-[[sup 18]F]fluoroprogestins are presented in chapter four. The radiochemical approaches towards the synthesis of these ligands are discussed. In chapter five the proposed routes to the fluorine-18 labelled [beta][sub 1]-adrenergic ligands are described and evaluated in the synthesis of two model compounds. 1-[[sup 18]F]fluorometoprolol, the [[sup 18]F]fluorinated analogue of a potent beta-blocker, is prepared using one of the investigated methods. The biological effect of fluorine substitution of a [beta][sub 1]-adrenergic ligand is discussed on the basis of an in vitro and in vivo evaluation. 21 figs., 28 schemes, 19 tabs., 182 refs.

Design, synthesis and biological evaluation of novel hydrogen sulfide releasing capsaicin derivatives.

Science.gov (United States)

Gao, Mingxiang; Li, Jinyu; Nie, Cunbin; Song, Beibei; Yan, Lin; Qian, Hai

2018-05-15

Capsaicin (CAP), the prototypical TRPV1 agonist, is the major active component in chili peppers with health-promoting benefits. However, its use is limited by the low bioavailability and irritating quality. In this study, for improving the activity of CAP and alleviating its irritating effects, a series of H 2 S-releasing CAPs were designed and synthesized by combining capsaicin and dihydro capsaicin with various hydrogen sulfide donors. The resulting compounds were evaluated their TRPV1 agonist activity, analgesic activity, anticancer activities, H 2 S-releasing ability, and gastric mucosa irritation. Biological evaluation indicated that the most active compound B 9 , containing 5-(4-hydroxyphenyl)-3H-1,2-dithiole-3-thione moiety as H 2 S donor, had better analgesic activity and displayed more potent cytotoxic effects on the test cell lines than the lead compound CAP. Furthermore, the preferred compound, B 9 reduced rat gastric mucosa irritation caused by CAP. Notably, the improved properties of this derivative are associated with its H 2 S-releasing capability. Copyright © 2018 Elsevier Ltd. All rights reserved.

Design, synthesis, and biological evaluation of enantiomeric beta-N-acetylhexosaminidase inhibitors LABNAc and DABNAc as potential agents against Tay-Sachs and Sandhoff disease.

Science.gov (United States)

Rountree, J S Shane; Butters, Terry D; Wormald, Mark R; Boomkamp, Stephanie D; Dwek, Raymond A; Asano, Naoki; Ikeda, Kyoko; Evinson, Emma L; Nash, Robert J; Fleet, George W J

2009-03-01

N-Acetylhexosaminidases are of considerable importance in mammals and are involved in various significant biological processes. In humans, deficiencies of these enzymes in the lysosome, resulting from inherited genetic defects, cause the glycolipid storage disorders Tay-Sachs and Sandhoff diseases. One promising therapy for these diseases involves the use of beta-N-acetylhexosaminidase inhibitors as chemical chaperones to enhance the enzyme activity above sub-critical levels. Herein we describe the synthesis and biological evaluation of a potent inhibitor, 2-acetamido-1,4-imino-1,2,4-trideoxy-L-arabinitol (LABNAc), in a high-yielding 11-step procedure from D-lyxonolactone. The N-benzyl and N-butyl analogues were also prepared and found to be potent inhibitors. The enantiomers DABNAc and NBn-DABNAc were synthesised from L-lyxonolactone, and were also evaluated. The L-iminosugar LABNAc and its derivatives were found to be potent noncompetitive inhibitors of some beta-N-acetylhexosaminidases, while the D-iminosugar DABNAc and its derivatives were found to be weaker competitive inhibitors. These results support previous work postulating that D-iminosugar mimics inhibit D-glycohydrolases competitively, and that their corresponding L-enantiomers show noncompetitive inhibition of these enzymes. Molecular modelling studies confirm that the spatial organisation in enantiomeric inhibitors leads to a different overlay with the monosaccharide substrate. Initial cell-based studies suggest that NBn-LABNAc can act as a chemical chaperone to enhance the deficient enzyme's activity to levels that may cause a positive pharmacological effect. LABNAc, NBn-LABNAc, and NBu-LABNAc are potent and selective inhibitors of beta-N-acetylhexosaminidase and may be useful as therapeutic agents for treating adult Tay-Sachs and Sandhoff diseases.

Design, synthesis and biological evaluations of N-Hydroxy thienopyrimidine-2,4-diones as inhibitors of HIV reverse transcriptase-associated RNase H.

Science.gov (United States)

Kankanala, Jayakanth; Kirby, Karen A; Huber, Andrew D; Casey, Mary C; Wilson, Daniel J; Sarafianos, Stefan G; Wang, Zhengqiang

2017-12-01

Human immunodeficiency virus (HIV) reverse transcriptase (RT) associated ribonuclease H (RNase H) is the only HIV enzymatic function not targeted by current antiviral drugs. Although various chemotypes have been reported to inhibit HIV RNase H, few have shown significant antiviral activities. We report herein the design, synthesis and biological evaluation of a novel N-hydroxy thienopyrimidine-2,3-dione chemotype (11) which potently and selectively inhibited RNase H with considerable potency against HIV-1 in cell culture. Current structure-activity-relationship (SAR) identified analogue 11d as a nanomolar inhibitor of RNase H (IC 50  = 0.04 μM) with decent antiviral potency (EC 50  = 7.4 μM) and no cytotoxicity (CC 50  > 100 μM). In extended biochemical assays compound 11d did not inhibit RT polymerase (pol) while inhibiting integrase strand transfer (INST) with 53 fold lower potency (IC 50  = 2.1 μM) than RNase H inhibition. Crystallographic and molecular modeling studies confirmed the RNase H active site binding mode. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Synthesis, analysis and biological evaluation of new RGD mimetics

Czech Academy of Sciences Publication Activity Database

Balacheva, A. A.; Lambev, M. K.; Pashov, I.; Detcheva, R. L.; Sázelová, Petra; Momekov, G. Ts.; Kašička, Václav; Pajpanova, T. I.; Golovinsky, E. V.

2017-01-01

Roč. 49, SI E (2017), s. 7-10 ISSN 0324-1130. [Bulgarian Peptide Symposium /7./. Blagoevgrad, 10.06.2016-12.06.2016] Institutional support: RVO:61388963 Keywords : RGD * biological ly active peptides * cytotoxicity Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 0.238, year: 2016

Synthesis and biological activity of imidazopyridine anticoccidial agents: Part II.

Science.gov (United States)

Scribner, Andrew; Dennis, Richard; Lee, Shuliang; Ouvry, Gilles; Perrey, David; Fisher, Michael; Wyvratt, Matthew; Leavitt, Penny; Liberator, Paul; Gurnett, Anne; Brown, Chris; Mathew, John; Thompson, Donald; Schmatz, Dennis; Biftu, Tesfaye

2008-06-01

Coccidiosis is the major cause of morbidity and mortality in the poultry industry. Protozoan parasites of the genus Eimeria invade the intestinal lining of the avian host causing tissue pathology, poor weight gain, and in some cases mortality. Resistance to current anticoccidials has prompted the search for new therapeutic agents with potent in vitro and in vivo activity against Eimeria. Recently, we reported the synthesis and biological activity of potent imidazo[1,2-a]pyridine anticoccidial agents. Antiparasitic activity is due to inhibition of a parasite specific cGMP-dependent protein kinase (PKG). In this study, we report the synthesis and anticoccidial activity of a second set of such compounds, focusing on derivatization of the amine side chain at the imidazopyridine 7-position. From this series, several compounds showed subnanomolar in vitro activity and commercial levels of in vivo activity. However, the potential genotoxicity of these compounds precludes them from further development.

Synthesis and Biological Evaluation of Novel Phosphatidylcholine Analogues Containing Monoterpene Acids as Potent Antiproliferative Agents.

Directory of Open Access Journals (Sweden)

Anna Gliszczyńska

Full Text Available The synthesis of novel phosphatidylcholines with geranic and citronellic acids in sn-1 and sn-2 positions is described. The structured phospholipids were obtained in high yields (59-87% and evaluated in vitro for their cytotoxic activity against several cancer cell lines of different origin: MV4-11, A-549, MCF-7, LOVO, LOVO/DX, HepG2 and also towards non-cancer cell line BALB/3T3 (normal mice fibroblasts. The phosphatidylcholines modified with monoterpene acid showed a significantly higher antiproliferative activity than free monoterpene acids. The highest activity was observed for the terpene-phospholipids containing the isoprenoid acids in sn-1 position of phosphatidylcholine and palmitic acid in sn-2.

Synthesis, radiosynthesis and biological evaluation of quinoline carboxamide analogues of Talnetant (SB 223412) to study by PET or SPECT imaging the NK-3 receptor

International Nuclear Information System (INIS)

Bennacef, Idriss

2003-01-01

With the aim of visualizing NK-3 receptors in vivo by medical imaging techniques (positron emission tomography and single photon emission computed tomography), the synthesis of novel 2-phenylquinoline-4-carboxamides, derived from SB 223412 or SB 222 200, two non peptide potent (hNK-3-CHO: K i = 1.0 nM; K i = 4.4 nM respectively) and selective (NK-3/NK-1 ≥10 5 ) human NK-3 receptor antagonists, has been studied. The compounds obtained are characterized by the presence, on the quinoline moiety, of an atom of carbon, fluorine or iodine that can be substituted by their β + emitter (carbon-11, t(1/2) = 20 min; fluorine-18, t(1/2) = 110 min) or γ emitter (iodine-123, t(1/2) = 13 h) radio-isotopes. Monohalogenated (fluorinated or iodinated) quinolines were prepared using an efficient synthesis based on the Pfitzinger reaction. Di-halogenated analogues, bearing both an iodine and a fluorine atom, were obtained via a regioselective ortho-metalation reaction. Biological evaluation of these compounds led to the determination of potent and selective structures towards the NK-3 receptor, for which labeling will be envisaged. Functionalization in position 3 of quinoline-4-carboxamides, using a directed metalation reaction, allowed the introduction of various (hetero)elements (chlorine, bromine, iodine, trialkystannyle or silyle moiety). This research allowed to perform the radiosynthesis of [ 11 C]SB 222200 using a Stille coupling with [ 11 C]iodomethane. (author) [fr

Design, Synthesis and Biological Evaluation of Benzohydrazide Derivatives Containing Dihydropyrazoles as Potential EGFR Kinase Inhibitors

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Hai-Chao Wang

2016-08-01

Full Text Available A series of novel benzohydrazide derivatives containing dihydropyrazoles have been synthesized as potential epidermal growth factor receptor (EGFR kinase inhibitors and their biological activities as potential antiproliferative agents have been evaluated. Among these compounds, compound H20 exhibited the most potent antiproliferative activity against four cancer cell line variants (A549, MCF-7, HeLa, HepG2 with IC50 values of 0.46, 0.29, 0.15 and 0.21 μM respectively, which showed the most potent EGFR inhibition activities (IC50 = 0.08 μM for EGFR. Molecular modeling simulation studies were performed in order to predict the biological activity and activity relationship (SAR of these benzohydrazide derivatives. These results suggested that compound H20 may be a promising anticancer agent.

Versatile synthesis and biological evaluation of novel 3’-fluorinated purine nucleosides

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Hang Ren

2015-12-01

Full Text Available A unified synthetic strategy accessing novel 3'-fluorinated purine nucleoside derivatives and their biological evaluation were achieved. Novel 3’-fluorinated analogues were constructed from a common 3’-deoxy-3’-fluororibofuranose intermediate. Employing Suzuki and Stille cross-coupling reactions, fifteen 3’-fluororibose purine nucleosides 1–15 and eight 3’-fluororibose 2-chloro/2-aminopurine nucleosides 16–23 with various substituents at position 6 of the purine ring were efficiently synthesized. Furthermore, 3’-fluorine analogs of natural products nebularine and 6-methylpurine riboside were constructed via our convergent synthetic strategy. Synthesized nucleosides were tested against HT116 (colon cancer and 143B (osteosarcoma cancer tumor cell lines. We have demonstrated 3’-fluorine purine nucleoside analogues display potent tumor cell growth inhibition activity at sub- or low micromolar concentration.

Natural occurrence, biological activities and synthesis of eight-, nine-, and eleven-membered ring lactones

Directory of Open Access Journals (Sweden)

Helena M. C. Ferraz

2008-01-01

Full Text Available The natural occurrence, biological activities and synthetic approaches to natural eight-, nine-, and eleven-membered lactones is reviewed. These medium ring lactones are grouped according to ring size, and their syntheses are discussed. The structures of some natural products early identified as medium-ring lactones were revised after total synthesis.

Synthesis, Biological Evaluation, and Molecular Modeling Studies of New Oxadiazole-Stilbene Hybrids against Phytopathogenic Fungi

Science.gov (United States)

Jian, Weilin; He, Daohang; Song, Shaoyun

2016-08-01

Natural stilbenes (especially resveratrol) play important roles in plant protection by acting as both constitutive and inducible defenses. However, their exogenous applications on crops as fungicidal agents are challenged by their oxidative degradation and limited availability. In this study, a new class of resveratrol-inspired oxadiazole-stilbene hybrids was synthesized via Wittig-Horner reaction. Bioassay results indicated that some of the compounds exhibited potent fungicidal activity against Botrytis cinerea in vitro. Among these stilbene hybrids, compounds 11 showed promising inhibitory activity with the EC50 value of 144.6 μg/mL, which was superior to that of resveratrol (315.6 μg/mL). Remarkably, the considerably abnormal mycelial morphology was observed in the presence of compound 11. The inhibitory profile was further proposed by homology modeling and molecular docking studies, which showed the possible interaction of resveratrol and oxadiazole-stilbene hybrids with the cytochrome P450-dependent sterol 14α-demethylase from B. cinerea (BcCYP51) for the first time. Taken together, these results would provide new insights into the fungicidal mechanism of stilbenes, as well as an important clue for biology-oriented synthesis of stilbene hybrids with improved bioactivity against plant pathogenic fungi in crop protection.

Synthesis and preliminary biological evaluations of (+)-isocampholenic acid-derived amides.

Science.gov (United States)

Grošelj, Uroš; Golobič, Amalija; Knez, Damijan; Hrast, Martina; Gobec, Stanislav; Ričko, Sebastijan; Svete, Jurij

2016-08-01

The synthesis of two novel (+)-isocampholenic acid-derived amines has been realized starting from commercially available (1S)-(+)-10-camphorsulfonic acid. The novel amines as well as (+)-isocampholenic acid have been used as building blocks in the construction of a library of amides using various aliphatic, aromatic, and amino acid-derived coupling partners using BPC and CDI as activating agents. Amide derivatives have been assayed against several enzymes that hold potential for the development of new drugs to battle bacterial infections and Alzheimer's disease. Compounds 20c and 20e showed promising selective sub-micromolar inhibition of human butyrylcholinesterase [Formula: see text] ([Formula: see text] values [Formula: see text] and [Formula: see text], respectively).

Use of biological indicators for evaluating environmental stress

International Nuclear Information System (INIS)

Letourneau, C.; Castonguay, J.

1988-09-01

This report examines the usefulness of biological analyses for evaluating environmental stress. All forms of stress are addressed; particular attention, however, is paid to the use of biological analyses to evaluate the impact on the environment from radioactive releases of the nuclear industry. First, we will review different biological analyses which are grouped into two approaches: the holistic approach (biotic and diversity indices) and the reductionist approach ('biological indicators' per se). Secondly, we will compare the usefulness of plants and animals as indicators based on the established criteria. This report ends with a compilation of letters received from different organizations which outline the present use in Canada of biological indicators for evaluating environmental stress

Use of biological indicators to evaluate environmental stress

International Nuclear Information System (INIS)

Letourneau, C.; Castonguay, J.

1987-09-01

This report examines the usefulness of biological analyses for evaluating environmental stress. All forms of stress are addressed; particular attention, however, is paid to the use of biological analyses to evaluate the impact on the environment from radioactive releases of the nuclear industry. First, we will review different biological analyses which are grouped into two approaches: the holistic approach (biotic and diversity indices) and the reductionist approach ('biological indicators' per se). Secondly, we will compare the usefulness of plants and animals as indicators based on the established criteria. This report ends with a compilation of letters received from different organizations which outline the present usage in Canada of biological indicators for evaluating environmental stress

A Practical Green Synthesis and Biological Evaluation of Benzimidazoles Against Two Neglected Tropical Diseases: Chagas and Leishmaniasis.

Science.gov (United States)

Bandyopadhyay, Debashis; Samano, Selina; Villalobos-Rocha, Juan Carlos; Sanchez-Torres, Luvia Enid; Nogueda-Torres, Benjamin; Rivera, Gildardo; Banik, Bimal K

2017-01-01

Antimicrobial resistance is an ever-increasing problem throughout the world and has already reached severe proportions. Two very common neglected tropical diseases are Chagas' disease and leishmaniasis. Chagas' disease is a severe health problem, mainly in Latin America, causing approximately 50000 deaths a year and millions of people are infected. About 25-30% of the patients infected with Trypanosoma cruzi develop the chronic form of the disease. On the other hand, Leishmaniasis represents complex diseases with an important clinical and epidemiological diversity. It is endemic in 88 countries 72 of which are developing countries and it has been estimated that are 12 million people infected and 350 million are in areas with infection risk. On this basis, research on organic compounds that can be used against these two diseases is an important target. A very simple, green, and efficient protocol is developed in which bismuth nitrate pentahydrate is employed as a Lewis acid catalyst in aqueous media under microwave irradiation for the synthesis of various 2-aryl substituted benzimidazoles from aldehydes and o-phenylenediamine. Other salient features of this protocol include milder conditions, atom-economy, easy extraction, and no wastes. Nine 1H-benzimidazole derivatives (1-9) with substituents at positions 2 and 5 were synthesized and the structure of the compounds was elucidated by spectroscopic methods. The compounds were screened to identify whether they posses pharmacological activity against Chagas' disease and leishmaniasis. Compound 8 showed better activity than the control Nifurtimox against INC-5 Trypanosoma cruzi strain whereas compounds 3 and 9 have demonstrated potent leshmanicidal activity. A systematic green synthetic procedure and in vitro biological evaluation of nine 1H-benzimidazoles are described. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Design, Synthesis, and Biological Evaluation of Isothiosemicarbazones with Antimycobacterial Activity

Czech Academy of Sciences Publication Activity Database

Novotná, E.; Waisser, K.; Kuneš, J.; Palát, K.; Skálová, L.; Szotáková, B.; Buchta, V.; Stolaříková, J.; Ulmann, V.; Pávová, Marcela; Weber, Jan; Komrsková, J.; Hašková, P.; Vokřál, I.; Wsól, V.

2017-01-01

Roč. 350, č. 8 (2017), č. článku e1700020. ISSN 0365-6233 Institutional support: RVO:61388963 Keywords : biological activity * cytotoxicity * isocitrate lyase * isothiosemicarbazone * tuberculosis Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 1.994, year: 2016

Synthesis and biological evaluation of arctigenin ester and ether derivatives as activators of AMPK.

Science.gov (United States)

Shen, Sida; Zhuang, Jingjing; Chen, Yijia; Lei, Min; Chen, Jing; Shen, Xu; Hu, Lihong

2013-07-01

A series of new arctigenin and 9-deoxy-arctigenin derivatives bearing different ester and ether side chains at the phenolic hydroxyl positions are designed, synthesized, and evaluated for activating AMPK potency in L6 myoblasts. Initial biological evaluation indicates that some alkyl ester and phenethyl ether arctigenin derivatives display potential activities in AMPK phosphorylation improvement. Further structure-activity relationship analysis shows that arctigenin ester derivatives 3a, 3h and 9-deoxy-arctigenin phenethyl ether derivatives 6a, 6c, 6d activate AMPK more potently than arctigenin. Moreover, the 2-(3,4-dimethoxyphenyl)ethyl ether moiety of 6c has been demonstrated as a potential functional group to improve the effect of AMPK phosphorylation. The structural optimization of arctigenin leads to the identification of 6c as a promising lead compound that exhibits excellent activity in AMPK activation. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Imidazopyridine-based inhibitors of glycogen synthase kinase 3: synthesis and evaluation of amide isostere replacements of the carboxamide scaffold.

Science.gov (United States)

Yngve, Ulrika; Söderman, Peter; Svensson, Mats; Rosqvist, Susanne; Arvidsson, Per I

2012-11-01

In this study, we explored the effect of bioisostere replacement in a series of glycogen synthase kinase 3 (GSK3) inhibitors based on the imidazopyridine core. The synthesis and biological evaluation of a number of novel sulfonamide, 1,2,4-oxadiazole, and thiazole derivates as amide bioisosteres, as well as a computational rationalization of the obtained results are reported. Copyright © 2012 Verlag Helvetica Chimica Acta AG, Zürich.

‘PROTEIN SYNTHESIS GAME’: UTILIZING GAME-BASED APPROACH FOR IMPROVING COMMUNICATIVE SKILLS IN A-LEVELS BIOLOGY CLASS

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Mohd Adlan Ramly

2017-12-01

Full Text Available This experimental paper seeks to elucidate the usage of the card game ‘Protein Synthesis Game’ as a student’s learning tool in studying the Biology topic of protein synthesis during an A-Level course. A total of 24 experimental students in 3 induced groups and 24 controlled students in controlled groups were involved in the experiment which began with a pretest on the topic of Protein Synthesis, followed by the experimentation, and ended with a post-test administered after the incubation period. Results indicate that students have better facilitative communicative engagement in learning protein synthesis when playing the game as compared to studying the topic from a book. The data suggests that such communicative engagement may lead to a successful meaningful learning on the students’ part.

Palladium- and copper-mediated N-aryl bond formation reactions for the synthesis of biological active compounds

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Burkhard Koenig

2011-01-01

Full Text Available N-Arylated aliphatic and aromatic amines are important substituents in many biologically active compounds. In the last few years, transition-metal-mediated N-aryl bond formation has become a standard procedure for the introduction of amines into aromatic systems. While N-arylation of simple aromatic halides by simple amines works with many of the described methods in high yield, the reactions may require detailed optimization if applied to the synthesis of complex molecules with additional functional groups, such as natural products or drugs. We discuss and compare in this review the three main N-arylation methods in their application to the synthesis of biologically active compounds: Palladium-catalysed Buchwald–Hartwig-type reactions, copper-mediated Ullmann-type and Chan–Lam-type N-arylation reactions. The discussed examples show that palladium-catalysed reactions are favoured for large-scale applications and tolerate sterically demanding substituents on the coupling partners better than Chan–Lam reactions. Chan–Lam N-arylations are particularly mild and do not require additional ligands, which facilitates the work-up. However, reaction times can be very long. Ullmann- and Buchwald–Hartwig-type methods have been used in intramolecular reactions, giving access to complex ring structures. All three N-arylation methods have specific advantages and disadvantages that should be considered when selecting the reaction conditions for a desired C–N bond formation in the course of a total synthesis or drug synthesis.

Design, Synthesis and Biological Evaluation of Histone Deacetylase (HDAC) Inhibitors: Saha (Vorinostat) Analogs and Biaryl Indolyl Benzamide Inhibitors Display Isoform Selectivity

Science.gov (United States)

Negmeldin, Ahmed Thabet

HDAC proteins have emerged as interesting targets for anti-cancer drugs due to their involvement in cancers, as well as several other diseases. Several HDAC inhibitors have been approved by the FDA as anti-cancer drugs, including SAHA (suberoylanilide hydroxamic acid, Vorinostat). Unfortunately, SAHA inhibits most HDAC isoforms, which limit its use as a pharmacological tool and may lead to side effects in the clinic. In this work we were interested in developing isoform selective HDAC inhibitors, which may decrease or eliminate the side effects associated with non-selective inhibitors treatment. In addition, isoform selective HDAC inhibitors can be used as biological tools to help understand the HDAC-related cancer biology. Our strategy was based on synthesis and screening of several derivatives of the non-selective FDA approved drug SAHA substituted at different positions of the linker region. Several SAHA analogs modified at the C4 and C5 positions of the linker were synthesized. The new C4- and C5-modified SAHA libraries, along with the previously synthesized C2-modified SAHA analogs were screened in vitro and in cellulo for HDAC isoform selectivity. Interestingly, several analogs exhibited dual HDAC6/HDAC8 selectivity. Enantioselective syntheses of the pure enantiomers of some of the interesting analogs were performed and the enantiomers were screened in vitro. Among the most interesting analogs, ( R)-C4-benzyl SAHA displayed 520- to 1300-fold selectivity for HDAC6 and HDAC8 over HDAC1, 2, and 3, with IC50 values of 48 and 27 nM with HDAC6 and 8, respectively. Docking studies were performed to provide structural rationale for the observed selectivity of the new analogs. In addition, rational design, synthesis, and screening of several other biaryl indolyl benzamide HDAC inhibitors is discussed, and some showed modest HDAC1 selectivity. The new biaryl indolyl benzamides can be useful to further develop HDAC1 selective inhibitors. The dual HDAC6/8 selective

Surface capped fluorescent semiconductor nanoparticles: radiolytic synthesis and some of its biological applications

International Nuclear Information System (INIS)

Saha, A.

2006-01-01

Semiconductor nanocrystals or colloidal quantum dots (QD's) have generated great research interest because of their unusual properties arising out of quantum confinement effects. Many researchers in the field of nanotechnology focus on the 'high quality' semiconductor quantum dots. A good synthetic route should yield nanoparticles with narrow size distribution, good crystallinity, high photostability, desired surface properties and high photoluminescence quantum efficiency. In the domain of colloidal chemistry, reverse micellar synthesis, high temperature thermolysis using organometallic precursors and synthesis in aqueous media using polyphosphates or thiols as stabilizers are the most prominent ones. In contrast, γ-radiation assisted synthesis can offer a simplified approach to prepare size-controlled nanoparticles at room temperature. Syntheses of thiol-capped II-VI nanoparticles by radiolytic method, its characterization and some of its luminescence-based applications of biological relevance will be presented. The versatility of thiols (RSH) can be emphasized here as changing the R-group imparts different functionality to the particles and thus chemical behavior of the particles can be manipulated according to the application intended for. (authors)

Synthesis and bioactive evaluations of novel benzotriazole ...

Indian Academy of Sciences (India)

Synthesis and bioactive evaluations of novel benzotriazole compounds as ... School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, .... −3 mol/L) was prepared by dissolving its solid in doubly distilled water.

Synthesis of hydroxyapatite with the use of calcium carbonate as of the biological precursor

International Nuclear Information System (INIS)

Aguilar, M.S.; Di Lello, B.C.; Queiroz, F.; Campos, N.C.; Campos, J.B.

2014-01-01

This work describes the synthesis of hydroxyapatite from calcium from biological materials such as shells carbonate. In the syntheses performed, the calcium carbonate of biological origin was used as the precursor and through a precipitation reaction with phosphoric acid, was converted into calcium hydroxide. Sequentially, the precipitate was aged, filtered, washed, dried and calcined, and then transformed into hydroxyapatite. The characterization of the powders was performed by X-DR (X-ray diffraction) and SEM (scanning electron microscopy). DR-X as determined hydroxyapatite calcium phosphate phase calcium. SEM revealed a morphology of finely divided particles. The method B.E.T. showed values of specific area and volume of micropores consistent with the literature. The results of the characterizations proved feasible to use for obtaining biological hydroxyapatite materials used in the reaction conditions.(author)

Novel multi-target-directed ligands for Alzheimer's disease: Combining cholinesterase inhibitors and 5-HT6 receptor antagonists. Design, synthesis and biological evaluation.

Science.gov (United States)

Więckowska, Anna; Kołaczkowski, Marcin; Bucki, Adam; Godyń, Justyna; Marcinkowska, Monika; Więckowski, Krzysztof; Zaręba, Paula; Siwek, Agata; Kazek, Grzegorz; Głuch-Lutwin, Monika; Mierzejewski, Paweł; Bienkowski, Przemysław; Sienkiewicz-Jarosz, Halina; Knez, Damijan; Wichur, Tomasz; Gobec, Stanislav; Malawska, Barbara

2016-11-29

As currently postulated, a complex treatment may be key to an effective therapy for Alzheimer's disease (AD). Recent clinical trials in patients with moderate AD have shown a superior effect of the combination therapy of donepezil (a selective acetylcholinesterase inhibitor) with idalopirdine (a 5-HT 6 receptor antagonist) over monotherapy with donepezil. Here, we present the first report on the design, synthesis and biological evaluation of a novel class of multifunctional ligands that combines a 5-HT 6 receptor antagonist with a cholinesterase inhibitor. Novel multi-target-directed ligands (MTDLs) were designed by combining pharmacophores directed against the 5-HT 6 receptor (1-(phenylsulfonyl)-4-(piperazin-1-yl)-1H-indole) and cholinesterases (tacrine or N-benzylpiperidine analogues). In vitro evaluation led to the identification of tacrine derivative 12 with well-balanced potencies against the 5-HT 6 receptor (K b  = 27 nM), acetylcholinesterase and butyrylcholinesterase (IC 50 hAChE  = 12 nM, IC 50 hBuChE  = 29 nM). The compound also showed good in vitro blood-brain-barrier permeability (PAMPA-BBB assay), which was confirmed in vivo (open field study). Central cholinomimetic activity was confirmed in vivo in rats using a scopolamine-induced hyperlocomotion model. A novel class of multifunctional ligands with compound 12 as the best derivative in a series represents an excellent starting point for the further development of an effective treatment for AD. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Book review: Biology and conservation of martens, sables, and fishers: A new synthesis

Science.gov (United States)

Jenkins, Kurt J.

2013-01-01

Mammals of the genus Martes, including martens, sables, and fishers, are mid-sized carnivores inhabiting many forested ecosystems throughout regions of North America, Europe, and Asia. This volume provides a comprehensive synthesis of the current state of knowledge pertaining to the biology and conservation of Martes species throughout the world. This volume will be an essential resource for mammalogists, resource managers, and applied ecologists involved in research or conservation of martens, sables, and fishers. For that matter, anyone seeking a full immersion in the modern world of Martes biology and conservation will not be disappointed. The volume has been carefully edited and reviewed, and the thoroughness with which the authors present and interpret recent advances in their specialty areas is really quite impressive.

BASIC SYNTHESIS AND BIOLOGICAL ACTIVITY OF SOME PHOSPHORCONTATNING ORGANIC COMPOUNDS CONTAINING FRAGMENTS OF UREA AND TRYHLORETILAMID

OpenAIRE

Gushylyk B.

2013-01-01

Data about directions of synthesis and use of the phosphororganic compounds in technics, biology and medicine is presented in the paper. Antimicrobial activity of 51 phosphororganic salts and ilides containing urine and threechlor ethylenamide has been studied. Perspective of the development of effective antimicrobial substances has been determined

Camels, Cormorants, and Kangaroo Rats: Integration and Synthesis in Organismal Biology After World War II.

Science.gov (United States)

Hagen, Joel B

2015-01-01

During the decades following World War II diverse groups of American biologists established a variety of distinctive approaches to organismal biology. Rhetorically, organismal biology could be used defensively to distinguish established research traditions from perceived threats from newly emerging fields such as molecular biology. But, organismal biologists were also interested in integrating biological disciplines and using a focus on organisms to synthesize levels of organization from molecules and cells to populations and communities. Part of this broad movement was the development of an area of research variously referred to as physiological ecology, environmental physiology, or ecophysiology. This area of research was distinctive in its self-conscious blend of field and laboratory practices and its explicit integration with other areas of biology such as ecology, animal behavior, and evolution in order to study adaptation. Comparing the intersecting careers of Knut Schmidt-Nielsen and George Bartholomew highlights two strikingly different approaches to physiological ecology. These alternative approaches to studying the interactions of organisms and environments also differed in important ways from the organismal biology championed by leading figures in the modern synthesis.

synthesis and characterization of some poly functionalized heterocyclic derivatives of expected biological activity

International Nuclear Information System (INIS)

El-sayed, M.S.

2001-01-01

The present work was aimed and designed to fulfil The following objectives : 1- Continuation of the effort done by our research group in the field of chemistry of pyridinethione derivatives and their biological activities. 2- Synthesis of several new heterocyclic derivatives containing N and/or S using the laboratory available reagents. 3- Establishment of the structures of the newly synthesized heterocyclic compounds by the data of IR, 1 H-NMR, mass spectra in addition to the elemental analysis. 4- Synthesis of some of these heterocyclic derivatives via alternative routs and this used as a tool to confirm the structures of the newly synthesized heterocyclic derivatives. 5- study of the most probable mechanisms leading to the formation of the new heterocyclic derivatives. 6- The antimicrobial activity of some of the newly synthesized heterocyclic derivatives was tested against several types of organisms

BASIC SYNTHESIS AND BIOLOGICAL ACTIVITY OF SOME PHOSPHORCONTATNING ORGANIC COMPOUNDS CONTAINING FRAGMENTS OF UREA AND TRYHLORETILAMID

Directory of Open Access Journals (Sweden)

Gushylyk B.

2013-10-01

Full Text Available Data about directions of synthesis and use of the phosphororganic compounds in technics, biology and medicine is presented in the paper. Antimicrobial activity of 51 phosphororganic salts and ilides containing urine and threechlor ethylenamide has been studied. Perspective of the development of effective antimicrobial substances has been determined

Insulin-like Growth Factor 1 Analogs Clicked in the C Domain: Chemical Synthesis and Biological Activities

Czech Academy of Sciences Publication Activity Database

Macháčková, Kateřina; Collinsová, Michaela; Chrudinová, Martina; Selicharová, Irena; Pícha, Jan; Buděšínský, Miloš; Vaněk, Václav; Žáková, Lenka; Brzozowski, A. M.; Jiráček, Jiří

2017-01-01

Roč. 60, č. 24 (2017), s. 10105-10117 ISSN 0022-2623 Institutional support: RVO:61388963 Keywords : IGF-1 * receptor * synthesis * triazole Subject RIV: CE - Biochemistry OBOR OECD: Biochemistry and molecular biology Impact factor: 6.259, year: 2016 http://pubs.acs.org/doi/full/10.1021/acs.jmedchem.7b01331

Bio-templated CdSe quantum dots green synthesis in the functional protein, lysozyme, and biological activity investigation

International Nuclear Information System (INIS)

Wang, Qisui; Li, Song; Liu, Peng; Min, Xinmin

2012-01-01

Bifunctional fluorescence (CdSe Quantum Dots) – protein (Lysozyme) nanocomposites were synthesized at room temperature by a protein-directed, solution-phase, green-synthetic method. Fluorescence (FL) and absorption spectra showed that CdSe QDs were prepared successfully with Lyz. The average particle size and crystalline structure of QDs were investigated by high-resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD), respectively. With attenuated total reflection-fourier transform infrared (ATR-FTIR) spectra and thermogravimetric (TG) analysis, it was confirmed that there is interaction between QDs and amide I, amide II groups in Lyz. FL polarization was measured and FL imaging was done to monitor whether QDs could be responsible for possible changes in the conformation and activity of Lyz. Interestingly, the results showed Lyz still retain the biological activity after formation of QDs, but the secondary structure of the Lyz was changed. And the advantage of this synthesis method is producing excellent fluorescent QDs with specifically biological function. -- Highlights: ► Lysozyme-directed green synthesis of CdSe quantum dots. ► Lysozyme still retain the biological activity after formation of CdSe. ► The method is the production of fluorescent QDs with highly specific and functions.

Synthesis and Biological Evaluation of 2H-Indazole Derivatives: Towards Antimicrobial and Anti-Inflammatory Dual Agents

Directory of Open Access Journals (Sweden)

Jaime Pérez-Villanueva

2017-10-01

Full Text Available Indazole is considered a very important scaffold in medicinal chemistry. It is commonly found in compounds with diverse biological activities, e.g., antimicrobial and anti-inflammatory agents. Considering that infectious diseases are associated to an inflammatory response, we designed a set of 2H-indazole derivatives by hybridization of cyclic systems commonly found in antimicrobial and anti-inflammatory compounds. The derivatives were synthesized and tested against selected intestinal and vaginal pathogens, including the protozoa Giardia intestinalis, Entamoeba histolytica, and Trichomonas vaginalis; the bacteria Escherichia coli and Salmonella enterica serovar Typhi; and the yeasts Candida albicans and Candida glabrata. Biological evaluations revealed that synthesized compounds have antiprotozoal activity and, in most cases, are more potent than the reference drug metronidazole, e.g., compound 18 is 12.8 times more active than metronidazole against G. intestinalis. Furthermore, two 2,3-diphenyl-2H-indazole derivatives (18 and 23 showed in vitro growth inhibition against Candida albicans and Candida glabrata. In addition to their antimicrobial activity, the anti-inflammatory potential for selected compounds was evaluated in silico and in vitro against human cyclooxygenase-2 (COX-2. The results showed that compounds 18, 21, 23, and 26 display in vitro inhibitory activity against COX-2, whereas docking calculations suggest a similar binding mode as compared to rofecoxib, the crystallographic reference.

Synthesis and biological evaluations of a series of thaxtomin analogues.

Science.gov (United States)

Zhang, Hongbo; Wang, Qingpeng; Ning, Xin; Hang, Hang; Ma, Jing; Yang, Xiande; Lu, Xiaolin; Zhang, Jiabao; Li, Yonghong; Niu, Congwei; Song, Haoran; Wang, Xin; Wang, Peng George

2015-04-15

Thaxtomins are a unique family of phytotoxins with unique 4-nitroindole and diketopiperazine fragments possessing potential herbicidal activities. This work presents the total synthesis of natural product thaxtomin C and its analogues. The extensive structure-activity relationship study screens four effective compounds, including thaxtomin A and thaxtomin C. It is indicated that 4-nitro indole fragment is essential for phytotoxicity, while benzyl and m-hydroxybenzyl substituents on the diketopiperazine ring are favorable for the efficacy. The N-methylations on indole and diketopiperazine show weak influence on the herbicidal activities. The four selected compounds show effective herbicidal activities against Brassica campestris, Amaranthus retroflexus, and Abutilon theophrasti, which are comparable or better than dichlobenil, even at a dosage of 187.5 g ha(-1). Moreover, these four compounds show good crop-selective properties to different crops and exhibit moderate protoporphyrinogen oxidase (PPO) enzyme inhibition. The antifungal results indicate that thaxtomin C displays inhibition to a wide range of fungi.

Synthesis, biological distribution and radiation dosimetry of Te-123m analogues of hexadecenoic acid

International Nuclear Information System (INIS)

Basmadjian, G.P.; Ice, R.D.; Mills, S.L.

1982-01-01

The synthesis and biological distribution of four Te-123m analogues of hexadecenoic acid in rats, rabbits and dogs were described for use as possible myocardial imaging agents. The heart-to-blood ratios ranged from 0.13 for 3-telluranonadecenoic acid in rats at 5 mins to 6.25 for 18-methyl-17-tellura-9-nonadecenoic acid in dogs at 24 hrs. The biological half-life of the Te-123m labelled fatty acids ranged from 26 to 583 hrs in the hearts of the test animals. These Te-123m fatty acids were retained in the heart longer than radioiodinated fatty acids and have acceptable absorbed doses to the various target organs. (U.K.)

Evolutionary systems biology: historical and philosophical perspectives on an emerging synthesis.

Science.gov (United States)

O'Malley, Maureen A

2012-01-01

Systems biology (SB) is at least a decade old now and maturing rapidly. A more recent field, evolutionary systems biology (ESB), is in the process of further developing system-level approaches through the expansion of their explanatory and potentially predictive scope. This chapter will outline the varieties of ESB existing today by tracing the diverse roots and fusions that make up this integrative project. My approach is philosophical and historical. As well as examining the recent origins of ESB, I will reflect on its central features and the different clusters of research it comprises. In its broadest interpretation, ESB consists of five overlapping approaches: comparative and correlational ESB; network architecture ESB; network property ESB; population genetics ESB; and finally, standard evolutionary questions answered with SB methods. After outlining each approach with examples, I will examine some strong general claims about ESB, particularly that it can be viewed as the next step toward a fuller modern synthesis of evolutionary biology (EB), and that it is also the way forward for evolutionary and systems medicine. I will conclude with a discussion of whether the emerging field of ESB has the capacity to combine an even broader scope of research aims and efforts than it presently does.

Synthesis and biological evaluation of some N-(3-(1H-tetrazol-5-yl) phenyl)acetamide derivatives as novel non-carboxylic PTP1B inhibitors designed through bioisosteric modulation.

Science.gov (United States)

Maheshwari, Neelesh; Karthikeyan, Chandrabose; Bhadada, Shraddha V; Sahi, Chandan; Verma, Amit K; Hari Narayana Moorthy, N S; Trivedi, Piyush

2018-06-08

Described herein is the synthesis and biological evaluation of a series of non-carboxylic inhibitors of Protein Tyrosine Phosphatase 1B designed using bioisosteric replacement strategy. Six N-(3-(1H-tetrazol-5-yl)phenyl)acetamide derivatives designed employing the aforementioned strategy were synthesized and screened for PTP1B inhibitory activity. Among the synthesized compounds, compound NM-03 exhibited the most potent inhibitory activity with IC 50 value of 4.48 µM. Docking studies with NM-03 revealed the key interactions with desired amino acids in the binding site of PTP1B. Furthermore, compound NM-03 also elicited good in vivo activity. Taken together, the results of this study establish N-(3-(1H-tetrazole-5-yl)phenyl)-2-(benzo[d]oxazol-2-ylthio)acetamide (NM-03) as a valuable lead molecule with great potential for PTP1B inhibitor development targeting diabetes. Copyright © 2018 Elsevier Inc. All rights reserved.

A microsystem to evaluate the synthesis of [3H]leucine labeled proteins by macrophages

International Nuclear Information System (INIS)

Varesio, L.; Eva, A.

1980-01-01

A method is described for evaluating protein synthesis by adherent MPHI by measuring the incorporation of [ 3 H]leucine into TCA precipitable material. By using guanidine-HCl it was possible to remove completely the radiolabeled proteins from the adherent cells that were cultured in microwells, and retain TCA precipitable material. This procedure enabled the authors to harvest the TCA precipitable proteins with a semiautomatic cell harvester. The guanidine-HCl treatment did not affect the recovery of the radioactive proteins and did not alter the sensitivity of the assay. This method is very simple and rapid and, since it is suitable for processing microcultures, permits detailed studies on the biology of small numbers of MPHI. (Auth.)

Synthesis and biological activity of imidazopyridine anticoccidial agents: part I.

Science.gov (United States)

Scribner, Andrew; Dennis, Richard; Hong, Jean; Lee, Shuliang; McIntyre, Donald; Perrey, David; Feng, Dennis; Fisher, Michael; Wyvratt, Matthew; Leavitt, Penny; Liberator, Paul; Gurnett, Anne; Brown, Chris; Mathew, John; Thompson, Donald; Schmatz, Dennis; Biftu, Tesfaye

2007-01-01

Coccidiosis is the major cause of morbidity and mortality in the poultry industry. Protozoan parasites of the genus Eimeria invade the intestinal lining of the avian host causing tissue pathology, poor weight gain, and in some cases mortality. Resistance to current anticoccidials has prompted the search for new therapeutic agents with potent in vitro and in vivo activity against Eimeria. Antiparasitic activity is due to inhibition of a parasite specific cGMP-dependent protein kinase (PKG). In this study, we present the synthesis and biological activity of imidazo[1,2-a]pyridine anticoccidial agents. From this series, several compounds showed subnanomolar in vitro activity and commercial levels of in vivo activity. However, the potential genotoxicity of these compounds precludes them from further development.

Synthesis and biological evaluation of febrifugine analogues.

Science.gov (United States)

Mai, Huong Doan Thi; Thanh, Giang Vo; Tran, Van Hieu; Vu, Van Nam; Vu, Van Loi; Le, Cong Vinh; Nguyen, Thuy Linh; Phi, Thi Dao; Truong, Bich Ngan; Chau, Van Minh; Pham, Van Cuong

2014-12-01

A series of febrifugine analogues were designed and synthesized. Antimalarial activity evaluation of the synthetic compounds indicated that these derivatives had a strong inhibition against both chloroquine-sensitive and -resistant Plasmodium falciparum parasites. Many of them were found to be more active than febrifugine hydrochloride. The tested analogues had also a significant cytotoxicity against four cancer cell lines (KB, MCF7, LU1 and HepG2). Among the synthetic analogues, two compounds 17b and 17h displayed a moderate cytotoxicity while they exhibited a remarkable antimalarial activity.

Photoinduced catalytic synthesis of biologically important metabolites from formaldehyde and ammonia under plausible "prebiotic" conditions

Science.gov (United States)

Delidovich, I. V.; Taran, O. P.; Simonov, A. N.; Matvienko, L. G.; Parmon, V. N.

2011-08-01

The article analyzes new and previously reported data on several catalytic and photochemical processes yielding biologically important molecules. UV-irradiation of formaldehyde aqueous solution yields acetaldehyde, glyoxal, glycolaldehyde and glyceraldehyde, which can serve as precursors of more complex biochemically relevant compounds. Photolysis of aqueous solution of acetaldehyde and ammonium nitrate results in formation of alanine and pyruvic acid. Dehydration of glyceraldehyde catalyzed by zeolite HZSM-5-17 yields pyruvaldehyde. Monosaccharides are formed in the course of the phosphate-catalyzed aldol condensation reactions of glycolaldehyde, glyceraldehyde and formaldehyde. The possibility of the direct synthesis of tetroses, keto- and aldo-pentoses from pure formaldehyde due to the combination of the photochemical production of glycolahyde and phosphate-catalyzed carbohydrate chain growth is demonstrated. Erythrulose and 3-pentulose are the main products of such combined synthesis with selectivity up to 10%. Biologically relevant aldotetroses, aldo- and ketopentoses are more resistant to the photochemical destruction owing to the stabilization in hemiacetal cyclic forms. They are formed as products of isomerization of erythrulose and 3-pentulose. The conjugation of the concerned reactions results in a plausible route to the formation of sugars, amino and organic acids from formaldehyde and ammonia under presumed 'prebiotic' conditions.

Structure-Based Design: Synthesis, X-ray Crystallography, and Biological Evaluation of N-Substituted-4-Hydroxy-2-Quinolone-3-Carboxamides as Potential Cytotoxic Agents.

Science.gov (United States)

Sabbah, Dima A; Hishmah, Bayan; Sweidan, Kamal; Bardaweel, Sanaa; AlDamen, Murad; Zhong, Haizhen A; Abu Khalaf, Reema; Hasan Ibrahim, Ameerah; Al-Qirim, Tariq; Abu Sheikha, Ghassan; Mubarak, Mohammad S

2018-01-01

Oncogenic potential of phosphatidylinositol 3-kinase (PI3Kα) has been highlighted as a therapeutic target for anticancer drug design. Target compounds were designed to address the effect of different substitution patterns at the N atom of the carboxamide moiety on the bioactivity of this series. Synthesis of the targeted compounds, crystallography, biological evaluation tests against human colon carcinoma (HCT-116), and Glide docking studies. A new series of N-substituted- 4-hydroxy-2-quinolone-3-carboxamides was prepared and characterized by means of FT-IR, 1H and 13C NMR, and elemental analysis. In addition, the identity of the core nucleus 5 was successfully characterized with the aid of X-ray crystallography. Biological activity of prepared compounds was investigated in vitro against human colon carcinoma (HCT-116) cell line. Results revealed that these compounds inhibit cell proliferation and induce apoptosis through an increase in caspase-3 activity and a decrease in DNA cellular content. Compounds 7, 14, and 17 which have H-bond acceptor moiety on p-position displayed promising PI3Kα inhibitory activity. On the other hand, derivatives tailored with bulky and hydrophobic motifs (16 and 18) on o- and m-positions exhibited moderate activity. Molecular docking studies against PI3Kα and caspase-3 showed an agreement between the predicted binding affinity (ΔGobsd) and IC50 values of the derivatives for the caspase-3 model. Furthermore, Glide docking studies against PI3Kα demonstrated that the newly synthesized compounds accommodate PI3Kα kinase catalytic domain and form H-bonding with key binding residues. The series exhibited a potential PI3Kα inhibitory activity in HCT-116 cell line. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Synthesis and Antiplatelet Activity of Antithrombotic Thiourea Compounds: Biological and Structure-Activity Relationship Studies

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André Luiz Lourenço

2015-04-01

Full Text Available The incidence of hematological disorders has increased steadily in Western countries despite the advances in drug development. The high expression of the multi-resistance protein 4 in patients with transitory aspirin resistance, points to the importance of finding new molecules, including those that are not affected by these proteins. In this work, we describe the synthesis and biological evaluation of a series of N,N'-disubstituted thioureas derivatives using in vitro and in silico approaches. New designed compounds inhibit the arachidonic acid pathway in human platelets. The most active thioureas (compounds 3d, 3i, 3m and 3p displayed IC50 values ranging from 29 to 84 µM with direct influence over in vitro PGE2 and TXA2 formation. In silico evaluation of these compounds suggests that direct blockage of the tyrosyl-radical at the COX-1 active site is achieved by strong hydrophobic contacts as well as electrostatic interactions. A low toxicity profile of this series was observed through hemolytic, genotoxic and mutagenic assays. The most active thioureas were able to reduce both PGE2 and TXB2 production in human platelets, suggesting a direct inhibition of COX-1. These results reinforce their promising profile as lead antiplatelet agents for further in vivo experimental investigations.

Design, synthesis, and biological testing of thiosalicylamides as a novel class of calcium channel blockers.

Science.gov (United States)

Mehanna, Ahmed S; Kim, Jin Yung

2005-07-01

The current research aimed to investigate the importance of the heterocyclic ring system in the structure of the cardiovascular drug diltiazem for its calcium channel blocking activity. The manuscript describes the design, synthesis, and biological testing of a total of 10 S-(p-methoxybenzyl), N-substituted thiosalicylamides as a series of non-cyclic compounds derived from diltiazem's structure. The new compounds maintained all diltiazem pharmacophores except the thiazepine ring system. In vitro evaluation of the new series for calcium channel blocking effects revealed moderate activities with IC50 values in the range of 4.8-56.0 microM. The data suggest that the ring system is not essential for activity; however, its absence leads to a considerable drop of activity relative to that of diltiazem (IC50=0.3 microM). Compounds of the current series showed optimum activity when the aliphatic alkyl chain on the salicylamide nitrogen is part of a piperidine or piperazine ring system substituted at the terminal nitrogen with a benzyl group.

Synthesis and biological evaluation of structurally simplified noscapine analogues as microtubule binding agents

Czech Academy of Sciences Publication Activity Database

Ghaly, P.E.; Churchill, C.D.M.; Abou El-Magd, R.M.; Hájková, Zuzana; Dráber, Pavel; West, F.G.; Tuszyński, J.A.

2017-01-01

Roč. 95, č. 6 (2017), s. 649-655 ISSN 0008-4042 R&D Projects: GA ČR GA15-22194S Institutional support: RVO:68378050 Keywords : noscapine * microtubule * tubulin * cytotoxicity * microtubule dynamics * docking Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Biochemistry and molecular biology Impact factor: 1.080, year: 2016

SYNTHESIS AND CHARACTERIZATION OF N, N'-BIS-(3 ...

African Journals Online (AJOL)

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base complexes derived from Salicylaldehyde and histidine with some divalent transition metal ions. Furthermore, Syed (1993) reported the synthesis, characterization and biological evaluation of some. Schiff base metal complexes derived from Anthranilic acid-sugar and naturally occurring amino acid-sugar. Schiff bases ...

Biological evaluation of 99m Tc-N-(3-bromo-trimethyl-acetanilide)-iminodiacetic acid (99mTc mebrofenin) as hepatobiliary radiopharmaceutical

International Nuclear Information System (INIS)

Hamada, E.S.

1994-01-01

Technetium-99 m-N-(3-bromo-2,4,6-trimethyl acetanilide) iminodiacetic acid ( 99m Tc-Mebrofenin) has been described as having optimal properties as hepatobiliary radiopharmaceutical. This paper describes the synthesis, radiopharmaceutical preparation and biological distribution of new labeled compound. The biodistribution study of 99m Tc-Mebrofenin- was carried out in normal mice. The specificity for hepatobiliary excretion blood clearance and cumulative biliary excretion were evaluated in normal and cirrhotic rats. (author). 5 refs, 3 figs, 3 tabs

Synthesis, Characterization and Evaluation of the Cytotoxicity of Ni-Doped Zn(Se,S Quantum Dots

Directory of Open Access Journals (Sweden)

Melissa Cruz-Acuña

2015-01-01

Full Text Available Quantum dots (QDs are semiconductor nanocrystals with desirable optical properties for biological applications, such as bioimaging and drug delivery. However, the potential toxicity of these nanostructures in biological systems limits their application. The present work is focused on the synthesis, characterization, and evaluation of the toxicity of water-stable Ni-doped Zn(Se,S QDs. Also, the study of nondoped nanostructures was included for comparison purposes. Ni-doped nanostructures were produced from zinc chloride and selenide aqueous solutions in presence of 3-mercaptopropionic acid and Ni molar concentration of 0.001 M. In order to evaluate the potential cytoxicity of these doped nanostructures, human pancreatic carcinoma cells (PANC-1 were used as model. The cell viability was monitored in presence of Ni-doped Zn(Se,S QDs at concentrations ranging from 0 μg/mL to 500 μg/mL and light excited Ni-doped Zn(Se,S nanostructures were evaluated at 50 μg/mL. Results suggested that Ni-doped Zn(Se,S nanostructures were completely safe to PANC-1 when concentrations from 0 μg/mL to 500 μg/mL were used, whereas non-doped nanostructures evidenced toxicity at concentrations higher than 200 μg/mL. Also, Ni-doped Zn(Se,S QDs under light excitation do not evidence toxicity to PANC-1. These findings suggest strongly that Zn(Se,S nanostructures doped with nickel could be used in a safe manner in light-driving biological applications and drug delivery.

Organocatalytic Michael and Friedel–Crafts reactions in enantioselective synthesis of biologically active compounds

International Nuclear Information System (INIS)

Maltsev, O V; Beletskaya, Irina P; Zlotin, Sergei G

2011-01-01

Recent applications of organocatalytic Michael and Friedel–Crafts reactions in enantioselective synthesis of biologically active compounds: natural products, pharmaceutical agents and plant protection agents are reviewed. The key mechanisms of stereoinduction, types of organocatalysts and reagents used in these reactions are considered. The material is classified according to the type of newly formed bonds incorporating the asymmetric carbon atom, and the information for the most numerous C–C coupling reactions is systematized according to the natures of the electrophile and the nucleophile. The bibliography includes 433 references.

Terminator Operon Reporter: combining a transcription termination switch with reporter technology for improved gene synthesis and synthetic biology applications.

Science.gov (United States)

Zampini, Massimiliano; Mur, Luis A J; Rees Stevens, Pauline; Pachebat, Justin A; Newbold, C James; Hayes, Finbarr; Kingston-Smith, Alison

2016-05-25

Synthetic biology is characterized by the development of novel and powerful DNA fabrication methods and by the application of engineering principles to biology. The current study describes Terminator Operon Reporter (TOR), a new gene assembly technology based on the conditional activation of a reporter gene in response to sequence errors occurring at the assembly stage of the synthetic element. These errors are monitored by a transcription terminator that is placed between the synthetic gene and reporter gene. Switching of this terminator between active and inactive states dictates the transcription status of the downstream reporter gene to provide a rapid and facile readout of the accuracy of synthetic assembly. Designed specifically and uniquely for the synthesis of protein coding genes in bacteria, TOR allows the rapid and cost-effective fabrication of synthetic constructs by employing oligonucleotides at the most basic purification level (desalted) and without the need for costly and time-consuming post-synthesis correction methods. Thus, TOR streamlines gene assembly approaches, which are central to the future development of synthetic biology.

Synthesis of potentially bioactive compounds and tools for biological studies

International Nuclear Information System (INIS)

Cappa, F.

2014-01-01

NMR spectroscopy is one of the most versatile tools for studying structural parameters of organic and bioorganic compounds. It became a highly suitable method to achieve spectra simplification of macromolecules in combination with isotope labeling techniques. This technique is used to study protein structures, folding properties and mechanisms of chemical and biochemical reactions. Proteins typically feature a high molecular mass showing a high number of spin systems, being responsible for increasingly difficult to interpret NMR spectra, which is why it is essential to introduce 13 C- and 15 N- isotopes to obtain reasonable signal intensities. The development of a new synthetic route towards 13 C-isotope labeled Phenylalanine or precursors thereof, starting from inexpensive and easily accessible labeled starting materials, is the main purpose of this work. Label sources such as [ 13 C]-acetic acid, [ 13 C]-formaldehyde, [ 13 C]-allyl alcohol and [ 13 C]-glycine will be used. The synthetic pathway will be carried out in a way where the position-selective incorporation of labeled isotopes can be performed. This important feature of the synthesis may open access towards newly designed NMR-experiments. Key steps for the tested route are ring closing metatheses as well as indium mediated reactions. The second part of this work focuses on the field of sugar chemistry, in particular on the family of deoxy sugars, components of many natural products, found in different plants, fungi and bacteria. Deoxy sugars also participate in a wide range of biological processes. Special focus is given to 3-deoxy sugars and the research of a versatile and flexible synthetic route for their preparation starting from the easily accessible D-glyceraldehyde. These sugars are found on Gram-negative bacteria where they are a key component of the lipopolysaccharides, or where they can take place in the biosynthesis of aromatic amino acids in bacteria and plants. Being able to perform this

Design, synthesis and biological evaluation of novel ring-opened cromakalim analogues with relaxant effects on vascular and respiratory smooth muscles and as stimulators of elastin synthesis.

Science.gov (United States)

Bouhedja, Mourad; Peres, Basile; Fhayli, Wassim; Ghandour, Zeinab; Boumendjel, Ahcène; Faury, Gilles; Khelili, Smail

2018-01-20

Two new series of ring-opened analogues of cromakalim bearing sulfonylurea moieties (series A: with N-unmethylated sulfonylureas, series B: with N-methylated sulfonylureas) were synthesized and tested as relaxants of vascular and respiratory smooth muscles (rat aorta and trachea, respectively). Ex vivo biological evaluations indicated that the most active compounds, belonging to series B, displayed a marked vasorelaxant activity on endothelium-intact aortic rings and the trachea. A majority of series B compounds exhibited a higher vasorelaxant activity (EC 50  stronger relaxant effects on the trachea than the reference compound cromakalim (EC 50  = 124 μM), in particular compounds B4, B7 and B16 (EC 50   57 μM for all, and EC 50  > 200 μM for a majority of them), but some of them showed an interesting relaxing effect on trachea (i.e. A15 and A33, EC 50  = 30 μM). The most potent compounds of both series, i.e. A15, A33 and B16, tested on aortic rings in the presence of glibenclamide or 80 mM KCl, suggested that they acted as voltage-gated Ca 2+ channel blockers, like verapamil, instead of being ATP-potassium channel activators, as is cromakalim, the parent molecule. Further investigations on cultured vascular smooth muscle cells showed a strong stimulating effect on elastin synthesis, especially compound B16, which was more active at 20 μM than diazoxide, a reference ATP-sensitive potassium channel activator. Taken together, our results show that the N-methylation of the sulfonylurea moieties of ring-opened cromakalim analogues led to new compounds blocking calcium-gated channels, which had a major impact on the arterial and tracheal activities as well as selectivity. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Toward synthesizing executable models in biology.

Science.gov (United States)

Fisher, Jasmin; Piterman, Nir; Bodik, Rastislav

2014-01-01

Over the last decade, executable models of biological behaviors have repeatedly provided new scientific discoveries, uncovered novel insights, and directed new experimental avenues. These models are computer programs whose execution mechanistically simulates aspects of the cell's behaviors. If the observed behavior of the program agrees with the observed biological behavior, then the program explains the phenomena. This approach has proven beneficial for gaining new biological insights and directing new experimental avenues. One advantage of this approach is that techniques for analysis of computer programs can be applied to the analysis of executable models. For example, one can confirm that a model agrees with experiments for all possible executions of the model (corresponding to all environmental conditions), even if there are a huge number of executions. Various formal methods have been adapted for this context, for example, model checking or symbolic analysis of state spaces. To avoid manual construction of executable models, one can apply synthesis, a method to produce programs automatically from high-level specifications. In the context of biological modeling, synthesis would correspond to extracting executable models from experimental data. We survey recent results about the usage of the techniques underlying synthesis of computer programs for the inference of biological models from experimental data. We describe synthesis of biological models from curated mutation experiment data, inferring network connectivity models from phosphoproteomic data, and synthesis of Boolean networks from gene expression data. While much work has been done on automated analysis of similar datasets using machine learning and artificial intelligence, using synthesis techniques provides new opportunities such as efficient computation of disambiguating experiments, as well as the ability to produce different kinds of models automatically from biological data.

Semi-automatic synthesis and biological evaluation of 18F-FCH as an oncologic PET tracer

International Nuclear Information System (INIS)

Wu Zhanhong; Wang Shizhen; Zhou Qian; Fu Zhe; Qiu Feichan; Huo Li

2005-01-01

18 F-fluromethylcholine ( 18 F-FCH) as a PET tracer is synthesized. The semi-automatic synthesis assembly of 18 F-FCH is modified from CPCU(CTI). The radiochemical purity is measured by analytical HPLC. The radiochemical yield and the radiochemical purity of 18 F-FCH are 15% and >99%, respectively. The total radiosynthesis time is 55 min after EOB. The labeled product exhibited low toxicity. The biodistribution in normal mice and the toxicity are studied. PET imaging with 18 F-FCH is performed on tumor xenograft murine model. The semi-automatic synthesis assembly is promising to be used for routine clinic radiopharmaceutical preparation and preliminary study has shown the usefulness of 18 F-FCH as an oncologic PET tracer. (authors)

Synthesis and biological evaluation of novel 5-hydroxylaminoisoxazole derivatives as lipoxygenase inhibitors and metabolism enhancing agents.

Science.gov (United States)

Averina, Elena B; Vasilenko, Dmitry A; Gracheva, Yulia A; Grishin, Yuri K; Radchenko, Eugene V; Burmistrov, Vladimir V; Butov, Gennady M; Neganova, Margarita E; Serkova, Tatyana P; Redkozubova, Olga M; Shevtsova, Elena F; Milaeva, Elena R; Kuznetsova, Tamara S; Zefirov, Nikolay S

2016-02-15

A versatile synthesis of novel 5-hydroxylaminoisoxazoles bearing adamantane moieties has been accomplished using the heterocyclization reactions of readily available unsaturated esters by the treatment with tetranitromethane in the presence of triethylamine and subsequent reduction of resulting 5-nitroisoxazoles by SnCl2 with the participation of THF. A number of obtained isoxazole derivatives were evaluated for their antioxidative activity, inhibition of lipoxygenases and impact on the rat liver mitochondria. The majority of tested compounds demonstrated moderate antiradical activity in DPPH test (up to EC50 16μM). The same compounds strongly inhibited soybean lipoxygenase (up to IC50 0.4μM) and Fe(2+)- and Fe(3+)-induced lipid peroxidation (LP) of rat brain cortex homogenate (up to IC50 0.3μM). All tested isoxazole derivatives promoted the phosphorylating respiratory activity simultaneously with maximal stimulated respiratory activity of mitochondria and do not reveal any toxicity towards the primary culture of rat cortex neurons. Copyright © 2015 Elsevier Ltd. All rights reserved.

Methods for the synthesis of aza(deaza)xanthines as a basis of biologically active compounds

International Nuclear Information System (INIS)

Babkov, D A; Geisman, A N; Novikov, M S; Khandazhinskaya, A L

2016-01-01

The review covers methods for the synthesis of aza(deaza)xanthines, i.e., fused pyrrolo-, pyrazolo- and triazolopyrimidine heterocyclic systems, which are common core structures of various biologically active compounds. The extensive range of modern synthetic approaches is organized according to target structures and starting building blocks. The presented material is intended to benefit broad audience of specialists in the fields of organic, medicinal and pharmaceutical chemistry. The bibliography includes 195 references

Synthesis, Characterization, and Biological Evaluation of Nanostructured Hydroxyapatite with Different Dimensions

Directory of Open Access Journals (Sweden)

Zhen Geng

2017-02-01

Full Text Available Nanosized hydroxyapatite (HA is a promising candidate for a substitute for apatite in bone in biomedical applications. Furthermore, due to its excellent bone bioactivity, nanosized strontium-substituted HA (SrHA has aroused intensive interest. However, the size effects of these nanoparticles on cellular bioactivity should be considered. In this study, nanosized HA and SrHA with different dimensions and crystallization were synthesized by hydrothermal methods. The phase, crystallization and chemical composition were analyzed by X-ray diffraction (XRD and Fourier transform infrared spectroscopy (FT-IR, respectively. The morphology was observed under field emission scanning electron microscopy (FE-SEM and transmission electron microscopy (TEM. The degradation behaviors of the samples were monitored by determining the ions release profile with inductively coupled plasma mass spectrometry (ICP-MS. The releasing behavior of Ca2+ and Sr2+ showed that the degradation rate was proportional to the specific surface area and inversely proportional to crystallization. The in vitro experiment evaluated by MG63 cells showed that SrHA nanorods with a length greater than 100 nm had the best biological performance both in cell proliferation and differentiation (* p < 0.05 compared with HA-1 and SrHA-1; * p < 0.01 compared with HA-2. In addition, HA nanoparticles with a lower aspect ratio had better bioactivity than higher ones (* p < 0.05. This study demonstrated that nanosized HA and SrHA with subtle differences (including dimensions, crystallization, specific surface area, and degradation rate could affect the cellular growth and thus might have an impact on bone growth in vivo. This work provides a view of the role of nano-HAs as ideal biocompatible materials in future clinical applications.

Synthesis and Preliminary Biological Evaluations of Fluorescent or 149Promethium Labeled Trastuzumab-Polyethylenimine

Directory of Open Access Journals (Sweden)

Jonathan Fitzsimmons

2015-12-01

Full Text Available Background: Radioimmunotherapy utilize a targeting antibody coupled to a therapeutic isotope to target and treat a tumor or disease. In this study we examine the synthesis and cell binding of a polymer scaffold containing a radiotherapeutic isotope and a targeting antibody. Methods: The multistep synthesis of a fluorescent or 149Promethium-labeled Trastuzumab-polyethyleneimine (PEI, Trastuzumab, or PEI is described. In vitro uptake, internalization and/or the binding affinity to the Her2/neu expressing human breast adenocarcinoma SKBr3 cells was investigated with the labeled compounds. Results: Fluorescent-labeled Trastuzumab-PEI was internalized more into cells at 2 and 18 h than fluorescent-labeled Trastuzumab or PEI. The fluorescent-labeled Trastuzumab was concentrated on the cell surface at 2 and 18 h and the labeled PEI had minimal uptake. DOTA-PEI was prepared and contained an average of 16 chelates per PEI; the compound was radio-labeled with 149Promethium and conjugated to Trastuzumab. The purified 149Pm-DOTA-PEI-Trastuzumab had a radiochemical purity of 96.7% and a specific activity of 0.118 TBq/g. The compound demonstrated a dissociation constant for the Her2/neu receptor of 20.30 ± 6.91 nM. Conclusion: The results indicate the DOTA-PEI-Trastuzumab compound has potential as a targeted therapeutic carrier, and future in vivo studies should be performed.

Towards Synthesizing Executable Models in Biology

Directory of Open Access Journals (Sweden)

Jasmin eFisher

2014-12-01

Full Text Available Over the last decade, executable models of biological behaviors have repeatedly provided new scientific discoveries, uncovered novel insights, and directed new experimental avenues. These models are computer programs whose execution mechanistically simulates aspects of the cell’s behaviors. If the observed behavior of the program agrees with the observed biological behavior, then the program explains the phenomena. This approach has proven beneficial for gaining new biological insights and directing new experimental avenues. One advantage of this approach is that techniques for analysis of computer programs can be applied to the analysis of executable models. For example, one can confirm that a model agrees with experiments for all possible executions of the model (corresponding to all environmental conditions, even if there are a huge number of executions. Various formal methods have been adapted for this context, for example, model checking or symbolic analysis of state spaces. To avoid manual construction of executable models, one can apply synthesis, a method to produce programs automatically from high-level specifications. In the context of biological modelling, synthesis would correspond to extracting executable models from experimental data. We survey recent results about the usage of the techniques underlying synthesis of computer programs for the inference of biological models from experimental data. We describe synthesis of biological models from curated mutation experiment data, inferring network connectivity models from phosphoproteomic data, and synthesis of Boolean networks from gene expression data. While much work has been done on automated analysis of similar datasets using machine learning and artificial intelligence, using synthesis techniques provides new opportunities such as efficient computation of disambiguating experiments, as well as the ability to produce different kinds of models automatically from biological data.

Synthesis of DOTA-conjugated multimeric [Tyr3]octreotide peptides via a combination of Cu(I)-catalyzed "click" cycloaddition and thio acid/sulfonyl azide "sulfo-click" amidation and their in vivo evaluation.

NARCIS (Netherlands)

Yim, C.B.; Dijkgraaf, I.; Merkx, R.; Versluis, C.; Eek, A.; Mulder, G.E.; Rijkers, D.T.; Boerman, O.C.; Liskamp, R.M.

2010-01-01

Herein, we describe the design, synthesis, and biological evaluation of a series of DOTA-conjugated monomeric, dimeric, and tetrameric [Tyr(3)]octreotide-based analogues as a tool for tumor imaging and/or radionuclide therapy. These compounds were synthesized using a Cu(I)-catalyzed 1,3-dipolar

Synthesis and biological evaluation of trans-3-phenyl-1-indanamines as potential norepinephrine transporter imaging agents

International Nuclear Information System (INIS)

McConathy, Jonathan; Owens, Michael J.; Kilts, Clinton D.; Malveaux, Eugene J.; Votaw, John R.; Nemeroff, Charles B.; Goodman, Mark M.

2005-01-01

The development of radioligands suitable for studying the central nervous system (CNS) norepinephrine transporter (NET) in vivo will provide important new tools for examining the pathophysiology and pharmacotherapy of a variety of neuropsychiatric disorders including major depression. Towards this end, a series of trans-3-phenyl-1-indanamine derivatives were prepared and evaluated in vitro. The biological properties of the most promising compound, [ 11 C]3-BrPA, were investigated in rat biodistribution and nonhuman primate PET studies. Despite high in vitro affinity for the human NET, the uptake of [ 11 C]3-BrPA in the brain and the heart was not displaceable with pharmacological doses of NET antagonists

Synthesis, characterization, and evaluation of the antimicrobial efficacy of Boswellia ovalifoliolata stem bark-extract-mediated zinc oxide nanoparticles

Science.gov (United States)

Supraja, N.; Prasad, T. N. V. K. V.; Krishna, T. Giridhara; David, E.

2016-04-01

Synthesis of metal nanoparticles using biological systems is an expanding research area in nanotechnology. Moreover, search for new nanoscale antimicrobials is been always attractive as they find numerous avenues for application in medicine. Biosynthesis of metallic nanoparticles is cost effective and eco-friendly compared to those of conventional methods of nanoparticles synthesis. Herein, we present the synthesis of zinc oxide nanoparticles using the stem bark extract of Boswellia ovalifoliolata, and evaluation of their antimicrobial efficacy. Stable ZnO nanoparticles were formed by treating 90 ml of 1 mM zinc nitrate aqueous solution with 10 ml of 10 % bark extract. The formation of B. ovalifoliolata bark-extract-mediated zinc oxide nanoparticles (BZnNPs) was confirmed by UV-visible spectroscopic analysis and recorded the localized surface plasmon resonance (LSPR) at 230 nm. Fourier transform infrared spectroscopic (FT-IR) analysis revealed that primary and secondary amine groups in combination with the proteins present in the bark extract are responsible for the reduction and stabilization of the BZnNPs. The morphology and crystalline phase of the nanocrystals were determined by Transmission electron microscopy (TEM). The hydrodynamic diameter (20.3 nm) and a positive zeta potential (4.8 mV) were measured using the dynamic light scattering technique. The antimicrobial activity of BZnNPs was evaluated (in vitro) against fungi, Gram-negative, and Gram-positive bacteria using disk diffusion method which were isolated from the scales formed in drinking water PVC pipelines.

Synthesis of [13C6]-labelled phenethylamine derivatives for drug quantification in biological samples.

Science.gov (United States)

Karlsen, Morten; Liu, HuiLing; Berg, Thomas; Johansen, Jon Eigill; Hoff, Bård Helge

2014-05-15

The availability of high-quality (13)C-labelled internal standards will improve accurate quantification of narcotics and drugs in biological samples. Thus, the synthesis of 10 [(13)C6]-labelled phenethylamine derivatives, namely amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, 3,4-methylenedioxy-N-ethylamphetamine, 4-methoxyamphetamine, 4-methoxymethamphetamine, 3,5-dimethoxyphenethylamine 4-bromo-2,5-dimethoxyphenethylamine and 2,5-dimethoxy-4-iodophenethylamine, have been undertaken. [(13)C6]-Phenol proved to be an excellent starting material for making (13)C-labelled narcotic substances in the phenethylamine class, and a developed Stille-type coupling enabled an efficient synthesis of the 3,4-methylenedioxy and 4-methoxy derivatives. The pros and cons of alternative routes and transformations are also discussed. The [(13)C6]-labelled compounds are intended for use as internal standards in forensic analysis, health sciences and metabolomics studies by gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry. Copyright © 2014 John Wiley & Sons, Ltd.

Plant polyphenols: chemical properties, biological activities, and synthesis.

Science.gov (United States)

Quideau, Stéphane; Deffieux, Denis; Douat-Casassus, Céline; Pouységu, Laurent

2011-01-17

Eating five servings of fruits and vegetables per day! This is what is highly recommended and heavily advertised nowadays to the general public to stay fit and healthy! Drinking green tea on a regular basis, eating chocolate from time to time, as well as savoring a couple of glasses of red wine per day have been claimed to increase life expectancy even further! Why? The answer is in fact still under scientific scrutiny, but a particular class of compounds naturally occurring in fruits and vegetables is considered to be crucial for the expression of such human health benefits: the polyphenols! What are these plant products really? What are their physicochemical properties? How do they express their biological activity? Are they really valuable for disease prevention? Can they be used to develop new pharmaceutical drugs? What recent progress has been made toward their preparation by organic synthesis? This Review gives answers from a chemical perspective, summarizes the state of the art, and highlights the most significant advances in the field of polyphenol research. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Design, synthesis and biological evaluation of Erythrina alkaloid analogues as neuronal nicotinic acetylcholine receptor antagonists

DEFF Research Database (Denmark)

Crestey, François; Jensen, Anders A.; Borch, Morten

2013-01-01

The synthesis of a new series of Erythrina alkaloid analogues and their pharmacological characterization at various nicotine acetylcholine receptor (nAChR) subtypes are described. The compounds were designed to be simplified analogues of aromatic erythrinanes with the aim of obtaining subtype...

Synthesis, characterization and biological behavior of some Schiff's and Mannich base derivatives of Lamotrigine

Directory of Open Access Journals (Sweden)

A.A. Kulkarni

2017-02-01

Full Text Available A series of various Schiff's and Mannich base derivatives (N1–2 & ND1–6 of Lamotrigine with isatin and substituted isatin were synthesized to get more potent anticonvulsant agents. The starting material for the synthesis of various new Schiff's and Mannich base derivatives was isatin (1H-indole- 2, 3-dione which in turn was prepared from substituted isonitrosoacetanilide using aniline. Lamotrigine reacts with isatin & substituted isatin gave Schiff's bases (N1–2 which on reaction with various secondary amines (dimethylamine, diethylamine, morpholine produced Mannich bases (ND1–6. The structures of newly synthesized compounds were characterized by using TLC, UV, FT-IR, 1HNMR and studied for their anticonvulsant activity. Anticonvulsant activity of all the derivatives was evaluated by MES method using phenobarbitone sodium & Lamotrigine as standard drugs and % reduction of time spent by animals in extension, flexion, clonus, and stupor phase were noted. Compounds ND-4 and ND-6 showed significant anticonvulsant activity when compared with that of standard drugs. The remaining all compounds show moderate activity. Biological activity data of the synthesized derivatives revealed that, the synthesized derivatives are good anticonvulsant agents as compared to Lamotrigine.

Novel aminopyrimidinyl benzimidazoles as potentially antimicrobial agents: Design, synthesis and biological evaluation.

Science.gov (United States)

Liu, Han-Bo; Gao, Wei-Wei; Tangadanchu, Vijai Kumar Reddy; Zhou, Cheng-He; Geng, Rong-Xia

2018-01-01

A series of novel aminopyrimidinyl benzimidazoles as potentially antimicrobial agents were designed, synthesized and characterized by IR, NMR and HRMS spectra. The biological evaluation in vitro revealed that some of the target compounds exerted good antibacterial and antifungal activity in comparison with the reference drugs. Noticeably, compound 7d could effectively inhibit the growth of A. flavus, E. coli DH52 and MRSA with MIC values of 1, 1 and 8 μg/mL, respectively. Further studies revealed that pyrimidine derivative 7d could exhibit bactericidal mode of action against both Gram positive (S. aureus and MRSA) and Gram negative (P. aeruginosa) bacteria. The active molecule 7d showed low cell toxicity and did not obviously trigger the development of resistance in bacteria even after 16 passages. Furthermore, compound 7d was able to beneficially regulate reactive oxygen species (ROS) generation for an excellent safety profile. Molecular docking study revealed that compound 7d could bind with DNA gyrase by the formation of hydrogen bonds. The preliminary exploration for antimicrobial mechanism disclosed that compound 7d could effectively intercalate into calf thymus DNA to form a steady supramolecular complex, which might further block DNA replication to exert the powerful bioactivities. The binding investigation of compound 7d with human serum albumins (HSA) revealed that this molecule could be effectively transported by HSA. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

The Synthesis and Biological Evaluation of N-Substituted 1H-Benzimidazol-2-yl-1H-pyrazole-3,5-diamines

Czech Academy of Sciences Publication Activity Database

Jedinák, L.; Kryštof, Vladimír; Cankař, P.

2016-01-01

Roč. 53, č. 2 (2016), s. 499-507 ISSN 0022-152X Institutional support: RVO:61389030 Keywords : ONE-POT SYNTHESIS * BENZIMIDAZOLE DERIVATIVES * EFFICIENT SYNTHESIS Subject RIV: CE - Biochemistry Impact factor: 0.893, year: 2016

Synthesis and preliminary biological evaluation of a compound library of triazolylcyclitols.

Science.gov (United States)

Carrau, Gonzalo; Drewes, Carine C; Shimada, Ana Lúcia B; Bertucci, Ana; Farsky, Sandra H P; Stefani, Helio A; Gonzalez, David

2013-07-15

A small library of compounds was prepared by a combination of toluene dioxygenase (TDO)-catalyzed enzymatic dihydroxylation and copper(I)-catalyzed Hüisgen cycloaddition. Some compounds were obtained by coupling an alkyne and a conduritol derivative, while more complex structures were obtained by a double Hüisgen reaction of a dialkyne and two molecules of the cyclitol. The compounds were fully characterized and subjected to preliminary biological screening. Copyright © 2013 Elsevier Ltd. All rights reserved.

Pyridinoacridine alkaloids of marine origin: NMR and MS spectral data, synthesis, biosynthesis and biological activity

Directory of Open Access Journals (Sweden)

Louis P. Sandjo

2015-09-01

Full Text Available This review focuses on pyridoacridine-related metabolites as one biologically interesting group of alkaloids identified from marine sources. They are produced by marine sponges, ascidians and tunicates, and they are structurally comprised of four to eight fused rings including heterocycles. Acridine, acridone, dihydroacridine, and quinolone cores are features regularly found in these alkaloid skeletons. The lack of hydrogen atoms next to quaternary carbon atoms for two or three rings makes the chemical shift assignment a difficult task. In this regard, one of the aims of this review is the compilation of previously reported, pyridoacridine 13C NMR data. Observations have been made on the delocalization of electrons and the presence of some functional groups that lead to changes in the chemical shift of some carbon resonances. The lack of mass spectra information for these alkaloids due to the compactness of their structures is further discussed. Moreover, the biosynthetic pathways of some of these metabolites have been shown since they could inspire biomimetic synthesis. The synthesis routes used to prepare members of these marine alkaloids (as well as their analogues, which are synthesized for biological purposes are also discussed. Pyridoacridines were found to have a large spectrum of bioactivity and this review highlights and compares the pharmacophores that are responsible for the observed bioactivity.

Synthesis, radioiodination and biological evaluation of a novel phthalimide derivative

International Nuclear Information System (INIS)

Motaleb, M.A.; Abdel-Ghaney, I.Y.; Shamsel-Din, H.A.; Abdel-Bary, H.M.

2016-01-01

Biologically active novel phthalimide derivative, N-(5-(2-hydroxyphenyl)-4,5-dihydro-1H-pyrazol-3-yl)phthalimide (HPZPHT), was synthesized in excellent yield and characterized by IR, mass and 1 H NMR spectroscopy. It was radiolabeled with iodine-131 by direct electrophilic substitution reaction and radiochemical yield was determined by using different chromatographic techniques (HPLRC, paper chromatography and paper electrophoresis). 131 I-HPZPHT has high radiolabeling yield (98.00 ± 2.00 %), stability, solid tumor uptake and T/NT ratio (5.17 ± 0.03 at 30 min. post-injection) compared with many new tracers which have been developed in recent years. This study encourages the possible use of this tracer as a potential imaging and/or therapeutic agent for cancer. (author)

Teaching Synthetic Biology, Bioinformatics and Engineering to Undergraduates: The Interdisciplinary Build-a-Genome Course

Science.gov (United States)

Dymond, Jessica S.; Scheifele, Lisa Z.; Richardson, Sarah; Lee, Pablo; Chandrasegaran, Srinivasan; Bader, Joel S.; Boeke, Jef D.

2009-01-01

A major challenge in undergraduate life science curricula is the continual evaluation and development of courses that reflect the constantly shifting face of contemporary biological research. Synthetic biology offers an excellent framework within which students may participate in cutting-edge interdisciplinary research and is therefore an attractive addition to the undergraduate biology curriculum. This new discipline offers the promise of a deeper understanding of gene function, gene order, and chromosome structure through the de novo synthesis of genetic information, much as synthetic approaches informed organic chemistry. While considerable progress has been achieved in the synthesis of entire viral and prokaryotic genomes, fabrication of eukaryotic genomes requires synthesis on a scale that is orders of magnitude higher. These high-throughput but labor-intensive projects serve as an ideal way to introduce undergraduates to hands-on synthetic biology research. We are pursuing synthesis of Saccharomyces cerevisiae chromosomes in an undergraduate laboratory setting, the Build-a-Genome course, thereby exposing students to the engineering of biology on a genomewide scale while focusing on a limited region of the genome. A synthetic chromosome III sequence was designed, ordered from commercial suppliers in the form of oligonucleotides, and subsequently assembled by students into ∼750-bp fragments. Once trained in assembly of such DNA “building blocks” by PCR, the students accomplish high-yield gene synthesis, becoming not only technically proficient but also constructively critical and capable of adapting their protocols as independent researchers. Regular “lab meeting” sessions help prepare them for future roles in laboratory science. PMID:19015540

Science for Survival: The Modern Synthesis of Evolution and The Biological Sciences Curriculum Study

Science.gov (United States)

Green, Lisa Anne

In this historical dissertation, I examined the process of curriculum development in the Biological Sciences Curriculum Study (BSCS) in the United States during the period 1959-1963. The presentation of evolution in the high school texts was based on a more robust form of Darwinian evolution which developed during the 1930s and 1940s called "the modern synthesis of evolution." Building primarily on the work of historians Vassiliki Smocovitis and John L. Rudolph, I used the archival papers and published writings of the four architects of the modern synthesis and the four most influential leaders of the BSCS in regards to evolution to investigate how the modern synthetic theory of evolution shaped the BSCS curriculum. The central question was "Why was evolution so important to the BSCS to make it the central theme of the texts?" Important answers to this question had already been offered in the historiography, but it was still not clear why every citizen in the world needed to understand evolution. I found that the emphasis on natural selection in the modern synthesis shifted the focus away from humans as passive participants to the recognition that humans are active agents in their own cultural and biological evolution. This required re-education of the world citizenry, which was accomplished in part by the BSCS textbooks. I also found that BSCS leaders Grobman, Glass, and Muller had serious concerns regarding the effects of nuclear radiation on the human gene pool, and were actively involved in informing th public. Lastly, I found that concerns of 1950s reform eugenicists were addressed in the BSCS textbooks, without mentioning eugenics by name. I suggest that the leaders of the BSCS, especially Bentley Glass and Hermann J. Muller, thought that students needed to understand genetics and evolution to be able to make some of the tough choices they might be called on to make as the dominant species on earth and the next reproductive generation in the nuclear age. This

Synthesis and antibacterial activity of sulfonamide derivatives at C-8 ...

Indian Academy of Sciences (India)

showed higher antibacterial activity compared with standard drug ampicillin. Keywords. Synthesis ... factor-kB regulated gene products leading to potenti- ation of ... constituent of CNSL natural source to evaluate their biological activity by ... Analytical thin layer ..... cially available CNSL by a reported method.26 Accord-.

Biological-based and physical-based optimization for biological evaluation of prostate patient's plans

Science.gov (United States)

Sukhikh, E.; Sheino, I.; Vertinsky, A.

2017-09-01

Modern modalities of radiation treatment therapy allow irradiation of the tumor to high dose values and irradiation of organs at risk (OARs) to low dose values at the same time. In this paper we study optimal radiation treatment plans made in Monaco system. The first aim of this study was to evaluate dosimetric features of Monaco treatment planning system using biological versus dose-based cost functions for the OARs and irradiation targets (namely tumors) when the full potential of built-in biological cost functions is utilized. The second aim was to develop criteria for the evaluation of radiation dosimetry plans for patients based on the macroscopic radiobiological criteria - TCP/NTCP. In the framework of the study four dosimetric plans were created utilizing the full extent of biological and physical cost functions using dose calculation-based treatment planning for IMRT Step-and-Shoot delivery of stereotactic body radiation therapy (SBRT) in prostate case (5 fractions per 7 Gy).

Synthesis and Biological Evaluation of Ru(II) and Pt(II) Complexes Bearing Carboxyl Groups as Potential Anticancer Targeted Drugs.

Science.gov (United States)

Martínez, Ma Ángeles; Carranza, M Pilar; Massaguer, Anna; Santos, Lucia; Organero, Juan A; Aliende, Cristina; de Llorens, Rafael; Ng-Choi, Iteng; Feliu, Lidia; Planas, Marta; Rodríguez, Ana M; Manzano, Blanca R; Espino, Gustavo; Jalón, Félix A

2017-11-20

The synthesis and characterization of Pt(II) (1 and 2) and Ru(II) arene (3 and 4) or polypyridine (5 and 6) complexes is described. With the aim of having a functional group to form bioconjugates, one uncoordinated carboxyl group has been introduced in all complexes. Some of the complexes were selected for their potential in photodynamic therapy (PDT). The molecular structures of complexes 2 and 5, as well as that of the sodium salt of the 4'-(4-carboxyphenyl)-2,2':6',2″-terpyridine ligand (cptpy), were determined by X-ray diffraction. Different techniques were used to evaluate the binding capacity to model DNA molecules, and MTT cytotoxicity assays were performed against four cell lines. Compounds 3, 4, and 5 showed little tendency to bind to DNA and exhibited poor biological activity. Compound 2 behaves as bonded to DNA probably through a covalent interaction, although its cytotoxicity was very low. Compound 1 and possibly 6, both of which contain a cptpy ligand, were able to intercalate with DNA, but toxicity was not observed for 6. However, compound 1 was active in all cell lines tested. Clonogenic assays and apoptosis induction studies were also performed on the PC-3 line for 1. The photodynamic behavior for complexes 1, 5, and 6 indicated that their nuclease activity was enhanced after irradiation at λ = 447 nm. The cell viability was significantly reduced only in the case of 5. The different behavior in the absence or presence of light makes complex 5 a potential prodrug of interest in PDT. Molecular docking studies followed by molecular dynamics simulations for 1 and the counterpart without the carboxyl group confirmed the experimental data that pointed to an intercalation mechanism. The cytotoxicity of 1 and the potential of 5 in PDT make them good candidates for subsequent conjugation, through the carboxyl group, to "selected peptides" which could facilitate the selective vectorization of the complex toward receptors that are overexpressed in

Industrial scale gene synthesis.

Science.gov (United States)

Notka, Frank; Liss, Michael; Wagner, Ralf

2011-01-01

The most recent developments in the area of deep DNA sequencing and downstream quantitative and functional analysis are rapidly adding a new dimension to understanding biochemical pathways and metabolic interdependencies. These increasing insights pave the way to designing new strategies that address public needs, including environmental applications and therapeutic inventions, or novel cell factories for sustainable and reconcilable energy or chemicals sources. Adding yet another level is building upon nonnaturally occurring networks and pathways. Recent developments in synthetic biology have created economic and reliable options for designing and synthesizing genes, operons, and eventually complete genomes. Meanwhile, high-throughput design and synthesis of extremely comprehensive DNA sequences have evolved into an enabling technology already indispensable in various life science sectors today. Here, we describe the industrial perspective of modern gene synthesis and its relationship with synthetic biology. Gene synthesis contributed significantly to the emergence of synthetic biology by not only providing the genetic material in high quality and quantity but also enabling its assembly, according to engineering design principles, in a standardized format. Synthetic biology on the other hand, added the need for assembling complex circuits and large complexes, thus fostering the development of appropriate methods and expanding the scope of applications. Synthetic biology has also stimulated interdisciplinary collaboration as well as integration of the broader public by addressing socioeconomic, philosophical, ethical, political, and legal opportunities and concerns. The demand-driven technological achievements of gene synthesis and the implemented processes are exemplified by an industrial setting of large-scale gene synthesis, describing production from order to delivery. Copyright © 2011 Elsevier Inc. All rights reserved.

Building biological foundries for next-generation synthetic biology.

Science.gov (United States)

Chao, Ran; Yuan, YongBo; Zhao, HuiMin

2015-07-01

Synthetic biology is an interdisciplinary field that takes top-down approaches to understand and engineer biological systems through design-build-test cycles. A number of advances in this relatively young field have greatly accelerated such engineering cycles. Specifically, various innovative tools were developed for in silico biosystems design, DNA de novo synthesis and assembly, construct verification, as well as metabolite analysis, which have laid a solid foundation for building biological foundries for rapid prototyping of improved or novel biosystems. This review summarizes the state-of-the-art technologies for synthetic biology and discusses the challenges to establish such biological foundries.

From the "Modern Synthesis" to cybernetics: Ivan Ivanovich Schmalhausen (1884-1963) and his research program for a synthesis of evolutionary and developmental biology.

Science.gov (United States)

Levit, Georgy S; Hossfeld, Uwe; Olsson, Lennart

2006-03-15

Ivan I. Schmalhausen was one of the central figures in the Russian development of the "Modern Synthesis" in evolutionary biology. He is widely cited internationally even today. Schmalhausen developed the main principles of his theory facing the danger of death in the totalitarian Soviet Union. His great services to evolutionary and theoretical biology are indisputable. However, the received view of Schmalhausen's contributions to evolutionary biology makes an unbiased reading of his texts difficult. Here we show that taking all of his works into consideration (including those only available in Russian) paints a much more dynamic and exciting picture of what he tried to achieve. Schmalhausen pioneered the integration of a developmental perspective into evolutionary thinking. A main tool for achieving this was his approach to living objects as complex multi-level self-regulating systems. Schmalhausen put enormous effort into bringing this idea into fruition during the final stages of his career by combining evolutionary theory with cybernetics. His results and ideas remain thought-provoking, and his texts are of more than just historical interest. Copyright 2006 Wiley-Liss, Inc.

Synthesis and evaluation of [{sup 14}C]-Labelled and fluorescent-Tagged paclitaxel derivatives as new biological probes

Energy Technology Data Exchange (ETDEWEB)

Rao, C.S.; Chu, J.-J.; Lai, Y.-K. [Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan (China); Liu, R.-S. [Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan (China)

1998-11-01

Our present report deals with the preparation of hitherto unreported 7-([carbonyl-{sup 14}C]-acetyl)paclitaxel 4 and two new bioactive 7-substituted fluorescent taxoids (FITC 9 and rhodamine 11), as well as evaluation towards their applications as biological probes. The results in this report demonstrate that (a) the new paclitaxel derivatives 4, 9, 11 could be prepared with good yields starting from paclitaxel; (b) the [{sup 14}C]acetylation step was found to be better by using [{sup 14}C]acetic anhydride rather than [{sup 14}C]sodium acetate; (c) the radiochemical purity of 4 was 96% and its specific activity was 48 mCi/mmol; (d) the cytotoxicity of 4 was close to that of paclitaxel whereas 9, 11 were far less active than paclitaxel, but these cytotoxic levels were good enough for their biological applications; (e) the drug-quantitation by flow cytometric analysis using 9 and 11 was proved to be equally efficient with respect to the radioactivity-based determination employing 4; (f) the intracellular fluorescence mapping by 9 and 11 was found to be effective and the microtubule network pattern was visible in both the cases; (g) the overall fluorescence imaging efficiency was better with 11 while the intensity of fluorescence was higher with 9; (h) staining of nucleolus was observed in fluorescence studies of both 9 and 11. Based on these results, the newly prepared paclitaxel derivatives can be considered as efficient biological probes and should find further use in relevant applications. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

Imaging of Enzymes in the Steroid Biosynthetic Pathway: Synthesis of 18F-Labelled Tracers

International Nuclear Information System (INIS)

Erlandsson, Maria

2009-01-01

This thesis deals with the synthesis and development of 18 F-labelled alkyl etomidate and vorozole analogues, and their use as positron emission tomography (PET) tracers for the imaging of the steroid enzymes 11β-hydroxylase and aromatase. Two synthetic 18 F-labelling approaches to the etomidate and vorozole analogues were developed, and the analogues were evaluated in some biological assays. The two-step labelling method was used to synthesise many compounds for biological evaluation. In the first step, a 18 F-labelled intermediate based on a ditosylate or a halogenated diethyl ether was synthesised and used directly in the next alkylation step. The decay-corrected (d.c.) radiochemical yield was higher compared to other known two-step labelling methods. Once an appropriate candidate has been chosen for clinical evaluation, a one-step labelling method will be more suitable. We therefore developed a method based on precursors that had leaving groups at the end of their alkyl chains, and used these directly in the 18 F-labelling synthesis. The one-step 18 F-labelling synthesis required less reaction time and produced higher specific radioactivity and d.c. radiochemical yield than our two-step synthesis. With microwave heating, the reaction time was reduced to seconds and the d.c. radiochemical yield was better than that obtained with conventional heating. The one-step synthesis simplified the technical handling by allowing the tracer syntheses to be automated on the TRACERLab FX FN

Evaluating meta-ethnography: systematic analysis and synthesis of qualitative research.

Science.gov (United States)

Campbell, R; Pound, P; Morgan, M; Daker-White, G; Britten, N; Pill, R; Yardley, L; Pope, C; Donovan, J

2011-12-01

Methods for reviewing and synthesising findings from quantitative research studies in health care are well established. Although there is recognition of the need for qualitative research to be brought into the evidence base, there is no consensus about how this should be done and the methods for synthesising qualitative research are at a relatively early stage of development. To evaluate meta-ethnography as a method for synthesising qualitative research studies in health and health care. Two full syntheses of qualitative research studies were conducted between April 2002 and September 2004 using meta-ethnography: (1) studies of medicine-taking and (2) studies exploring patients' experiences of living with rheumatoid arthritis. Potentially relevant studies identified in multiple literature searches conducted in July and August 2002 (electronically and by hand) were appraised using a modified version of the Critical Appraisal Skills Programme questions for understanding qualitative research. Candidate papers were excluded on grounds of lack of relevance to the aims of the synthesis or because the work failed to employ qualitative methods of data collection and analysis. Thirty-eight studies were entered into the medicine-taking synthesis, one of which did not contribute to the final synthesis. The synthesis revealed a general caution about taking medicine, and that the practice of lay testing of medicines was widespread. People were found to take their medicine passively or actively or to reject it outright. Some, in particular clinical areas, were coerced into taking it. Those who actively accepted their medicine often modified the regimen prescribed by a doctor, without the doctor's knowledge. The synthesis concluded that people often do not take their medicines as prescribed because of concern about the medicines themselves. 'Resistance' emerged from the synthesis as a concept that best encapsulated the lay response to prescribed medicines. It was suggested that a

Synthesis and Biological Evaluation of Novel Benzimidazole Derivatives Bearing a Heterocyclic Ring at 4/5 Position

International Nuclear Information System (INIS)

Wubulikasimu, Reyila; Yang, Yanbing; Xue, Fei; Luo, Xianjin; Shao, Dongping; Li, Yuhuan; Gao, Rongmei; Ye, Weidong

2013-01-01

A series of novel benzimidazole derivatives bearing a heterocyclic ring as oxadiazole (21-32), thiadiazole (33-34), triazole (35-36) were synthesized and evaluated for their activities against Coxsackie virus B3 and B6 in Vero cells. Compounds 21-26, 31-36 with moieties of 2'-pyridyl, 3'-pyridyl and 4'-pyridyl at the 2-position and oxadiazoles, thiadiazole, or triazole substituent at the 4- or 5-position generally displayed activities against CVB3 and CVB6. Especially compound 24 (IC 50 = 1.08 μg/mL, SI = 61.7 against CVB3) was the promising candidate as lead compound for anti-enteroviral drug. It was observed in the incorporation of heterocyclic rings in benzimidazole at the 5-position could enhance their biological activities

Synthesis and biological investigation of PIM mimics carrying biotin or a fluorescent label for cellular imaging.

Science.gov (United States)

Front, Sophie; Bourigault, Marie-Laure; Rose, Stéphanie; Noria, Ségueni; Quesniaux, Valérie F J; Martin, Olivier R

2013-01-16

Phosphatidyl inositol mannosides (PIMs) are constituents of the mycobacterial cell wall; these glycolipids are known to exhibit potent inhibitory activity toward the LPS-induced production of cytokines by macrophages, and therefore have potential as anti-inflammatory agents. Recently, heterocyclic analogues of PIMs in which the inositol is replaced by a piperidine (aza-PIM mimics) or a tetrahydropyran moiety (oxa-PIM mimics) have been prepared by short synthetic sequences and shown to retain the biological activity of the parent PIM structures. In this investigation, the aza-PIM analogue was used as a convenient scaffold to link biotin or a fluorescent label (tetramethyl-rhodamine) by way of an aminocaproyl spacer, with the goal of using these conjugates for intracellular localization and for the study of the mechanism of their antiinflammatory action. The synthesis of these compounds is reported, as well as the evaluation of their activities as inhibitors of LPS-induced cytokine production by macrophages (TNFα, IL12p40); preliminary investigations by FACS and confocal microscopy indicated that PIM-biotin conjugate binds to macrophage membranes with rapid kinetics.

Protein synthesis evaluation in brain and other organs in human by PET

International Nuclear Information System (INIS)

Bustany, P.; Comar, D.

1985-01-01

The choice of treatment in diseases of the nervous system cannot be based only on symptomatology, but on a presumed underlying pathological state. These pathological states often involve direct modifications of neuronal metabolism. Two areas of cellular biochemistry can be studied in vivo in humans: 1) glucose or oxygen consumption which is mainly responsible for energy and lipid metabolism. 2) amino acid metabolism, which is involved in protein and neurotransmitter synthesis. Here the authors examine protein synthesis, which is the basis of cellular integrity and tissue structure. Study of protein synthesis (PS) by positron emission tomography (PET) is governed by specific requirements dictated by 1) the metabolic pathways we want to explore (the fate of the tracer directly influences the analysis of the results); 2) The construction and validation of a mathematical model to be applied to the computerized images; and 3) the human pathology being studied. The timing of scanning and the experimental protocol must include in their conception some physiological constraints such as volume of organs, rapidity of biological phenomena, etc. All these steps are detailed in the following paragraphs

Quinazoline derivatives: synthesis and bioactivities

OpenAIRE

Wang, Dan; Gao, Feng

2013-01-01

Owing to the significant biological activities, quinazoline derivatives have drawn more and more attention in the synthesis and bioactivities research. This review summarizes the recent advances in the synthesis and biological activities investigations of quinazoline derivatives. According to the main method the authors adopted in their research design, those synthetic methods were divided into five main classifications, including Aza-reaction, Microwave-assisted reaction, Metal-mediated reac...

Synthesis and Biological Assessment of Racemic Benzochromenopyrimidinimines as Antioxidant, Cholinesterase, and Aβ1-42 Aggregation Inhibitors for Alzheimer's Disease Therapy.

Science.gov (United States)

Dgachi, Youssef; Ismaili, Lhassane; Knez, Damijan; Benchekroun, Mohamed; Martin, Hélène; Szałaj, Natalia; Wehle, Sarah; Bautista-Aguilera, Oscar M; Luzet, Vincent; Bonnet, Alexandre; Malawska, Barbara; Gobec, Stanislav; Chioua, Mourad; Decker, Michael; Chabchoub, Fakher; Marco-Contelles, José

2016-06-20

Given the complex nature of Alzheimer's disease (AD), compounds that are able to simultaneously address two or more AD-associated targets show greater promise for development into drugs for AD therapy. Herein we report an efficient two-step synthesis and biological evaluation of new racemic benzochromene derivatives as antioxidants, inhibitors of cholinesterase and β-amyloid (Aβ1-42 ) aggregation. Based on the results of the primary screening, we identified 15-(3-methoxyphenyl)-9,11,12,15-tetrahydro-10H,14H-benzo[5,6]chromeno[2,3-d]pyrido[1,2-a]pyrimidin-14-imine (3 e) and 16-(3-methoxyphenyl)-9,10,11,12,13,16-hexahydro-15H-benzo[5',6']chromeno[2',3':4,5]pyrimido[1,2-a]azepin-15-imine (3 f) as new potential multitarget-directed ligands for AD therapy. Further in-depth biological analysis showed that compound 3 f is a good human acetylcholinesterase inhibitor [IC50 =(0.36±0.02) μm], has strong antioxidant activity (3.61 μmol Trolox equivalents), and moderate Aβ1-42 antiaggregating power (40.3 %). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

2-C-Branched mannosides as a novel family of FimH antagonists—Synthesis and biological evaluation

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Wojciech Schönemann

2017-01-01

Full Text Available Urinary tract infections (UTIs, which are among the most prevalent bacterial infections worldwide, are mainly attributed to uropathogenic Escherichia coli (UPEC. Because of frequent antibiotic treatment, antimicrobial resistance constitutes an increasing therapeutic problem. Antagonists of the mannose-specific bacterial lectin FimH, a key protein mediating the adhesion of UPEC to human bladder cells, would offer an alternative anti-adhesive treatment strategy. In general, FimH antagonists consist of a mannose moiety and a wide range of lipophilic aglycones. Modifications of the mannose core led to a distinct drop in affinity. A visual inspection of the crystal structure of FimH revealed a previously unexplored cavity surrounded by Ile13, Phe142 and Asp140, which could be reached by functional groups in the equatorial 2-position of the mannose. Here, we describe the synthesis of 2-C-branched mannosides and evaluation of their pharmacodynamic properties. ITC experiments with the selected antagonists revealed a drastic enthalpy loss for all 2-C-branched antagonists, which, however, is partially compensated by an entropy gain. This supports the hypothesis that the target cavity is too small to accommodate 2-C-substituents.

Modular Synthesis of Biologically Active Phosphatidic Acid Probes Using Click Chemistry

Science.gov (United States)

Smith, Matthew D.; Sudhahar, Christopher G.; Gong, Denghuang; Stahelin, Robert V.

2018-01-01

Phosphatidic acid (PA) is an important signaling lipid that plays roles in a range of biological processes including both physiological and pathophysiological events. PA is one of a number of signaling lipids that can act as site-specific ligands for protein receptors in binding events that enforce membrane-association and generally regulate both receptor function and subcellular localization. However, elucidation of the full scope of PA activities has proven problematic, primarily due to the lack of a consensus sequence among PA-binding receptors. Thus, experimental approaches, such as those employing lipid probes, are necessary for characterizing interactions at the molecular level. Herein, we describe an efficient modular approach to the synthesis of a range of PA probes that employs a late stage introduction of reporter groups. This strategy was exploited in the synthesis of PA probes bearing fluorescent and photoaffinity tags as well as a bifunctional probe containing both a photoaffinity moiety and an azide as a secondary handle for purification purposes. To discern the ability of these PA analogues to mimic the natural lipid in protein binding properties, each compound was incorporated into vesicles for binding studies using a known PA receptor, the C2 domain of PKCα. In these studies, each compound exhibited binding properties that were comparable to those of synthetic PA, indicating their viability as probes for effectively studying the activities of PA in cellular processes. PMID:19668861

Synthesis, spectroscopic characterization, biological screenings, DNA binding study and POM analyses of transition metal carboxylates

Science.gov (United States)

Uddin, Noor; Sirajuddin, Muhammad; Uddin, Nizam; Tariq, Muhammad; Ullah, Hameed; Ali, Saqib; Tirmizi, Syed Ahmed; Khan, Abdur Rehman

2015-04-01

This article contains the synthesis of a novel carboxylic acid derivative, its transition metal complexes and evaluation of biological applications. Six carboxylate complexes of transition metals, Zn(II) and Hg(II), have been successfully synthesized and characterized by FT-IR and NMR (1H, 13C). The ligand, HL, (4-[(2,6-Diethylphenyl)amino]-4-oxobutanoic acid) was also characterized by single crystal X-ray analysis. The complexation occurs via oxygen atoms of the carboxylate moiety. FT-IR date show the bidentate nature of the carboxylate moiety of the ligand as the Δν value in all complexes is less than that of the free ligand. The ligand and its complexes were screened for antifungal and antileishmanial activities. The results showed that the ligand and its complexes are active with few exceptions. UV-visible spectroscopy and viscometry results reveal that the ligand and its complexes interact with the DNA via intercalative mode of interaction. A new and efficient strategy to identify the pharmacophores and anti-pharmacophores sites in carboxylate derivatives for the antibacterial/antifungal activity using Petra, Osiris and Molinspiration (POM) analyses was also carried out.

Polycyclic Aromatic Compounds as Anticancer Agents: Synthesis and Biological Evaluation of Methoxy Dibenzofluorene Derivatives

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Bimal Krishna Banik

2014-08-01

Full Text Available Synthesis of a new methoxy dibenzofluorene through alkylation, cyclodehydration and aromatization in a one-pot operation is achieved for the first time. Using this hydrocarbon, a few derivatives are prepared through aromatic nitration, catalytic hydrogenation, coupling reaction with a side chain and reduction. The benzylic position of this hydrocarbon with the side chain is oxidized and reduced. Some of these derivatives have demonstrated excellent antitumor activities in vitro. This study confirms antitumor activity depends on the structures of the molecules.

Biology learning evaluation model in Senior High Schools

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Sri Utari

2017-06-01

Full Text Available The study was to develop a Biology learning evaluation model in senior high schools that referred to the research and development model by Borg & Gall and the logic model. The evaluation model included the components of input, activities, output and outcomes. The developing procedures involved a preliminary study in the form of observation and theoretical review regarding the Biology learning evaluation in senior high schools. The product development was carried out by designing an evaluation model, designing an instrument, performing instrument experiment and performing implementation. The instrument experiment involved teachers and Students from Grade XII in senior high schools located in the City of Yogyakarta. For the data gathering technique and instrument, the researchers implemented observation sheet, questionnaire and test. The questionnaire was applied in order to attain information regarding teacher performance, learning performance, classroom atmosphere and scientific attitude; on the other hand, test was applied in order to attain information regarding Biology concept mastery. Then, for the analysis of instrument construct, the researchers performed confirmatory factor analysis by means of Lisrel 0.80 software and the results of this analysis showed that the evaluation instrument valid and reliable. The construct validity was between 0.43-0.79 while the reliability of measurement model was between 0.88-0.94. Last but not the least, the model feasibility test showed that the theoretical model had been supported by the empirical data.

Synthesis and Spectral Evaluation of Some Unsymmetrical Mesoporphyrinic Complexes

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Rica Boscencu

2012-06-01

Full Text Available Synthesis and spectral evaluation of new zinc and copper unsymmetrical mesoporphyrinic complexes are reported. Zn(II-5-(4-acetoxy-3-methoxyphenyl-10,15,20-tris-(4-carboxymethylphenylporphyrin, Zn(II-5-[(3,4-methylenedioxyphenyl]-10,15,20-tris-(4-carboxymethylphenylporphyrin, Cu(II-5-(4-acetoxy-3-methoxyphenyl-10,15,20-tris-(4-carboxymethylphenylporphyrin and Cu(II-5-[(3,4-methylenedioxyphenyl]-10,15,20-tris-(4-carboxymethylphenylporphyrin were synthesized using microwave-assisted synthesis. The complexes were characterized by elemental analysis, FT-IR, UV-Vis, EPR and NMR spectroscopy, which fully confirmed their structure. The spectral absorption properties of the porphyrinic complexes were studied in solvents with different polarities. Fluorescence emission and singlet oxygen formation quantum yields were evaluated for the compounds under study, revealing high yields for the zinc derivatives. The copper complexes are not emissive and only display residual capacity for singlet oxygen formation.

Synthesis, crystal structure and biological activity of 2-hydroxyethylammonium salt of p-aminobenzoic acid.

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Manuela E Crisan

Full Text Available p-Aminobenzoic acid (pABA plays important roles in a wide variety of metabolic processes. Herein we report the synthesis, theoretical calculations, crystallographic investigation, and in vitro determination of the biological activity and phytotoxicity of the pABA salt, 2-hydroxyethylammonium p-aminobenzoate (HEA-pABA. The ability of neutral and anionic forms of pABA to interact with TIR1 pocket was investigated by calculation of molecular electrostatic potential maps on the accessible surface area, docking experiments, Molecular Dynamics and Quantum Mechanics/Molecular Mechanics calculations. The docking study of the folate precursor pABA, its anionic form and natural auxin (indole-3-acetic acid, IAA with the auxin receptor TIR1 revealed a similar binding mode in the active site. The phytotoxic evaluation of HEA-pABA, pABA and 2-hydroxyethylamine (HEA was performed on the model plant Arabidopsis thaliana ecotype Col 0 at five different concentrations. HEA-pABA and pABA acted as potential auxin-like regulators of root development in Arabidopsis thaliana (0.1 and 0.2 mM and displayed an agravitropic root response at high concentration (2 mM. This study suggests that HEA-pABA and pABA might be considered as potential new regulators of plant growth.

Synthetic biology analysed tools for discussion and evaluation

CERN Document Server

2016-01-01

Synthetic biology is a dynamic, young, ambitious, attractive, and heterogeneous scientific discipline. It is constantly developing and changing, which makes societal evaluation of this emerging new science a challenging task, prone to misunderstandings. Synthetic biology is difficult to capture, and confusion arises not only regarding which part of synthetic biology the discussion is about, but also with respect to the underlying concepts in use. This book offers a useful toolbox to approach this complex and fragmented field. It provides a biological access to the discussion using a 'layer' model that describes the connectivity of synthetic or semisynthetic organisms and cells to the realm of natural organisms derived by evolution. Instead of directly reviewing the field as a whole, firstly our book addresses the characteristic features of synthetic biology that are relevant to the societal discussion. Some of these features apply only to parts of synthetic biology, whereas others are relevant to synthetic bi...

Ethylene glycol monolayer protected nanoparticles: synthesis, characterization, and interactions with biological molecules.

Science.gov (United States)

Zheng, Ming; Li, Zhigang; Huang, Xueying

2004-05-11

The usefulness of the hybrid materials of nanoparticles and biological molecules on many occasions depends on how well one can achieve a rational design based on specific binding and programmable assembly. Nonspecific binding between nanoparticles and biomolecules is one of the major barriers for achieving their utilities in a biological system. In this paper, we demonstrate a new approach to eliminate nonspecific interactions between nanoparticles and biological molecules by shielding the nanoparticle with a monolayer of ethylene glycol. A direct synthesis of di-, tri-, and tetra(ethylene glycol)-protected gold nanoparticles (Au-S-EGn, n = 2, 3, and 4) was achieved under the condition that the water content was optimized in the range of 9-18% in the reaction mixture. With controlled ratio of [HAuCl4]/[EGn-SH] at 2, the synthesized particles have an average diameter of 3.5 nm and a surface plasma resonance band around 510 nm. Their surface structures were confirmed by 1H NMR spectra. These gold nanoparticles are bonded with a uniform monolayer with defined lengths of 0.8, 1.2, and 1.6 nm for Au-S-EG2, Au-S-EG3, and Au-S-EG4, respectively. They have great stabilities in aqueous solutions with a high concentration of electrolytes as well as in organic solvents. Thermogravimetric analysis revealed that the ethylene glycol monolayer coating is ca. 14% of the total nanoparticle weight. Biological binding tests by using ion-exchange chromatography and gel electrophoresis demonstrated that these Au-S-EGn (n = 2, 3, or 4) nanoparticles are free of any nonspecific bindings with various proteins, DNA, and RNA. These types of nanoparticles provide a fundamental starting material for designing hybrid materials composed of metallic nanoparticles and biomolecules.

[Synthesis and biological activity of 1,4-benzoquinone-guanylhydrazone-thiosemicarbazone analogs. 1. Substitution at the S atom].

Science.gov (United States)

Schulze, W; Gutsche, W; Wohlrabe, K; Fleck, W; Tresselt, D

1985-08-01

The synthesis of S-substituted derivatives of 1,4-benzoquinone-guanylhydrazone-thiosemicarbazone is described. The obtained 1,4-benzoquinone-guanylhydrazone-S-alkyl (resp. aralkyl)-isothiosemicarbazones, in comparison with the unsubstituted standard compound, showed a significantly decreased biological activity against the murine leukemias L 1210 and P 388 as well as against the growth of several kinds of bacteria. Therefore the S-substitution seems not to be useful for reaching a maximum activity.

Biological and biochemical evaluation of some prepared high ...

African Journals Online (AJOL)

Biological and biochemical evaluation of some prepared high antioxidant fruit beverages as functional foods. W A El-Malky ... The beverage which contain mango, red grape, carrot and tomato was the best prepared beverages according to the sensory evaluation, chemical composition and antioxidant activity. The high ...

Synthesis, radiosynthesis and biological evaluation of 1, 4-dihydroquinoline derivatives as new carriers for specific brain delivery

International Nuclear Information System (INIS)

Foucout, L.; Bohn, P.; Dupas, G.; Marsais, F.; Levacher, V.; Gourand, F.; Dhilly, M.; Barre, L.; Bohn, P.; Costentin, J.; Abbas, A.

2009-01-01

In spite of numerous reports dealing with the use of 1, 4-dihydro-pyridines as carriers to deliver biological active compounds to the brain, this chemical delivery system (CDS) suffers from poor stability of the 1, 4-dihydropyridine derivatives towards oxidation and hydration reactions seriously limiting further investigations in vivo. In an attempt to overcome these limitations, we report herein the first biological evaluation of more stable annellated NADH models in the quinoline series as relevant neuro-active drug-carrier candidates. The radiolabeled 1, 4-dihydroquinoline [ 11 C]1a was prepared to be subsequently peripherally injected in rats. The injected animals were sacrificed and brains were collected. The radioactivity measured in rat brain indicated a rapid penetration of the carrier [ 11 C]1a into the CNS. HPLC analysis of brain homogenates showed that oxidation of [ 11 C]1a into the corresponding quinolinium salt [ 11 C]4a was completed in less than 5 min. An in vivo evaluation in mice is also reported to illustrate the potential of such 1, 4-dihydroquinoline derivatives to transport a neuro-active drug in the CNS. For this purpose, g-aminobutyric acid (GABA), well known to poorly cross the brain blood barrier (BBB) was connected to this 1, 4-dihydroquinoline-type carrier. After i.p. injection of 1, 4-dihydroquinoline-GABA derivative 1b in mice, a significant alteration of locomotor activity (LMA) was observed presumably resulting from an enhancement of central GABAergic activity. These encouraging results give strong evidence for the capacity of carrier-GABA derivative 1b to cross the BBB and exert a pharmacological effect on the CNS. This study paves the way for further progress in designing new redox chemical delivery systems. (authors)

Synthesis, radiosynthesis and biological evaluation of 1, 4-dihydroquinoline derivatives as new carriers for specific brain delivery

Energy Technology Data Exchange (ETDEWEB)

Foucout, L.; Bohn, P.; Dupas, G.; Marsais, F.; Levacher, V. [Laboratoire de Chimie Organique Fine et Heterocyclique, UMR 6014, IRCOF, CNRS, Universite et INSA de Rouen, B.P. 08 F-76131, Mont- Saint-Aignan Cedex (France); Gourand, F.; Dhilly, M.; Barre, L. [Groupe de Developpements Methodologiques en Tomographie par Emission de Positons, CEA/DSV/I2BM/CI-NAPS UMR6232, Universite de Caen Basse Normandie, Caen (France); Bohn, P.; Costentin, J. [Laboratoire de Neuropharmacologie Experimentale associe au CNRS, FRE-2735, Faculte de Medecine et de pharmacie, Universite de Rouen, F-76000 (France); Abbas, A. [Inserm-EPHE-Universite de Caen Basse-Normandie, Unite U923, GIP Cyceron, CHU Cote de Nacre, Caen (France)

2009-07-01

In spite of numerous reports dealing with the use of 1, 4-dihydro-pyridines as carriers to deliver biological active compounds to the brain, this chemical delivery system (CDS) suffers from poor stability of the 1, 4-dihydropyridine derivatives towards oxidation and hydration reactions seriously limiting further investigations in vivo. In an attempt to overcome these limitations, we report herein the first biological evaluation of more stable annellated NADH models in the quinoline series as relevant neuro-active drug-carrier candidates. The radiolabeled 1, 4-dihydroquinoline [{sup 11}C]1a was prepared to be subsequently peripherally injected in rats. The injected animals were sacrificed and brains were collected. The radioactivity measured in rat brain indicated a rapid penetration of the carrier [{sup 11}C]1a into the CNS. HPLC analysis of brain homogenates showed that oxidation of [{sup 11}C]1a into the corresponding quinolinium salt [{sup 11}C]4a was completed in less than 5 min. An in vivo evaluation in mice is also reported to illustrate the potential of such 1, 4-dihydroquinoline derivatives to transport a neuro-active drug in the CNS. For this purpose, g-aminobutyric acid (GABA), well known to poorly cross the brain blood barrier (BBB) was connected to this 1, 4-dihydroquinoline-type carrier. After i.p. injection of 1, 4-dihydroquinoline-GABA derivative 1b in mice, a significant alteration of locomotor activity (LMA) was observed presumably resulting from an enhancement of central GABAergic activity. These encouraging results give strong evidence for the capacity of carrier-GABA derivative 1b to cross the BBB and exert a pharmacological effect on the CNS. This study paves the way for further progress in designing new redox chemical delivery systems. (authors)

Organic synthesis

International Nuclear Information System (INIS)

Lallemand, J.Y.; Fetizon, M.

1988-01-01

The 1988 progress report of the Organic Synthesis Chemistry laboratory (Polytechnic School, France), is presented. The laboratory activities are centered on the chemistry of natural products, which have a biological activity and on the development of new reactions, useful in the organic synthesis. The research works involve the following domains: the natural products chemistry which are applied in pharmacology, the plants and insects chemistry, the organic synthesis, the radical chemistry new reactions and the bio-organic physicochemistry. The published papers, the congress communications and the thesis are listed [fr

Design, synthesis, and biological evaluation of prenylated chalcones as 5-LOX inhibitors.

Science.gov (United States)

Reddy, Nimmanapalli P; Aparoy, Polamarasetty; Reddy, T Chandra Mohan; Achari, Chandrani; Sridhar, P Ramu; Reddanna, Pallu

2010-08-15

Ten novel mono- and di-O-prenylated chalcone derivatives were designed on the basis of a homology derived molecular model of 5-lipoxygenase (5-LOX). The compounds were docked into 5-LOX active site and the binding characteristics were quantified using LUDI. To verify our theoretical assumption, the molecules were synthesized and tested for their 5-LOX inhibitory activities. The synthesis was carried out by Claisen-Schmidt condensation reaction of mono- and di-O-prenylated acetophenones with appropriate aldehydes. 5-LOX in vitro inhibition assay showed higher potency of di-O-prenylated chalcones than their mono-O-prenylated chalcone analogs. Compound 5e exhibited good inhibition with an IC(50) at 4 microM. The overall trend for the binding energies calculated and LUDI score was in good qualitative agreement with the experimental data. Further, the compound 5e showed potent anti-proliferative effects (GI(50) at 9 microM) on breast cancer cell line, MCF-7. Copyright 2010 Elsevier Ltd. All rights reserved.

Design, synthesis, and evaluation of an alpha-helix mimetic library targeting protein-protein interactions.

Science.gov (United States)

Shaginian, Alex; Whitby, Landon R; Hong, Sukwon; Hwang, Inkyu; Farooqi, Bilal; Searcey, Mark; Chen, Jiandong; Vogt, Peter K; Boger, Dale L

2009-04-22

The design and solution-phase synthesis of an alpha-helix mimetic library as an integral component of a small-molecule library targeting protein-protein interactions are described. The iterative design, synthesis, and evaluation of the candidate alpha-helix mimetic was initiated from a precedented triaryl template and refined by screening the designs for inhibition of MDM2/p53 binding. Upon identifying a chemically and biologically satisfactory design and consistent with the screening capabilities of academic collaborators, the corresponding complete library was assembled as 400 mixtures of 20 compounds (20 x 20 x 20-mix), where the added subunits are designed to mimic all possible permutations of the naturally occurring i, i + 4, i + 7 amino acid side chains of an alpha-helix. The library (8000 compounds) was prepared using a solution-phase synthetic protocol enlisting acid/base liquid-liquid extractions for purification on a scale that insures its long-term availability for screening campaigns. Screening of the library for inhibition of MDM2/p53 binding not only identified the lead alpha-helix mimetic upon which the library was based, but also suggests that a digestion of the initial screening results that accompany the use of such a comprehensive library can provide insights into the nature of the interaction (e.g., an alpha-helix mediated protein-protein interaction) and define the key residues and their characteristics responsible for recognition.

Synthesis and biological incorporation of icons into macromolecules for NMR study. Final report, June 1, 1977--May 31, 1978

International Nuclear Information System (INIS)

Grant, D.M.; Horton, W.J.

1978-01-01

Carbon-13 enrichment synthesis and incorporation into three important biological systems have been carried out to provide materials for carbon-13 magnetic resonance studies. These systems include antibody-labeled haptens, labeled t-RNA and 5S-RNA molecules, and pyridoxal-5'-phosphate-labeled substrate mixtures. The synthesis phase of the work has been completed in all three cases, and the NMR studies completed on all but the antibody-hapten system which is still in process having been absorbed into other supported projects. Publications are now in preparation for the RNA and pyridoxal work. Preliminary results on the antibody-haptens work are encouraging as signals of antibody absorbed haptens have been observed but the results are still not yet conclusive

Convergent synthesis of a deuterium-labeled serine dipeptide lipid for analysis of biological samples.

Science.gov (United States)

Dietz, Christopher; Clark, Robert B; Nichols, Frank C; Smith, Michael B

2017-05-30

Bacterial serine dipeptide lipids are known to promote inflammatory processes and are detected in human tissues associated with periodontal disease or atherosclerosis. Accurate quantification of bacterial serine lipid, specifically lipid 654 [((S)-15-methyl-3-((13-methyltetradecanoyl)oxy)hexadecanoyl)glycyl-l-serine, (3S)-l-serine] isolated from Porphyromonas gingivalis, in biological samples requires the preparation of a stable isotope internal standard for sample supplementation and subsequent mass spectrometric analysis. This report describes the convergent synthesis of a deuterium-substituted serine dipeptide lipid, which is an isotopically labeled homologue that represents a dominant form of serine dipeptide lipid recovered in bacteria. Copyright © 2017 John Wiley & Sons, Ltd.

Quinoline based furanones and their nitrogen analogues: Docking, synthesis and biological evaluation

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Sukhbir Lal Khokra

2016-11-01

Full Text Available A small library of twenty-four quinoline based butenolides also known as furanones and their nitrogen analogues was prepared by using two different aroylpropionic acids, viz. 3-(2-naphthoylpropionic acid (3 and 3-(biphenyl-4-ylpropionic acid (4, as starting materials. The 3-aroylpropionic acids were reacted with different 6-substituted-2-chloroquinolin-3-carbaldehydes (2a–d to obtain the corresponding furan-2(3H-ones (5a–h. The purified and characterized furanones were then converted into their corresponding 2(3H-pyrrolones (6a–h and N-benzyl-pyrrol-2(3H-ones (7a–h. The antimicrobial activities of the title compounds were evaluated against two strains of each Gram +ve (Staphylococcus aureus and Bacillus subtilis, Gram −ve bacteria (Escherichia coli and Pseudomonas aeruginosa and against fungal strains of Aspergillus niger and Aspergillus flavus. In vivo anti-inflammatory potential of the title compounds was investigated by standard method. Majority of the compounds showed significant antibacterial activity against both the Gram +ve strains. Eight most potent anti-inflammatory compounds (5b, 5d, 5h, 6b, 7b, 7d, 7f, 7h which exhibited >53% inhibition in edema, were also screened for their in vivo analgesic activity. All the tested compounds were found to have significant reduction in ulcerogenic action but only three compounds (5d, 5h and 7h showed comparable analgesic activity to standard drug, diclofenac. The results were also validated using in silico approach and maximum mol doc score was obtained for compounds 7a–h. On comparing the in vivo and in silico anti-inflammatory results of synthesized compounds, N-benzyl pyrrolones (7a–h emerged as the potent anti-inflammatory agents. It was also observed that compounds that possess electron withdrawing group such as Cl or NO2 are more biologically active.

Enhancing Higher Order Thinking Skills In A Marine Biology Class Through Problem-Based Learning

Directory of Open Access Journals (Sweden)

Richard M. Magsino

2014-10-01

Full Text Available The purpose of this research was to examine students' perspectives of their learning in marine biology in the collaborative group context of Problem-based Learning (PBL. Students’ higher order thinking skills (HOTS using PBL involves the development of their logical thinking and reasoning abilities which stimulates their curiosity and associative thinking. This study aimed to investigate how critical thinking skills, particularly analysis, synthesis and evaluation were enhanced in a marine biology class through PBL. Qualitative research approach was used to examine student responses in a questionnaire involving 10 open-ended questions that target students’ HOTS on a problem presented in a marine biology class for BS Biology students. Using axial coding as a qualitative data analysis technique by which grounded theory can be performed, the study was able to determine how students manifest their higher reasoning abilities when confronted with a marine biology situation. Results show student responses yielding affirmative remarks on the 10 questions intended to know their level of analysis (e.g., analyzing, classifying, inferring, discriminating and relating or connecting, synthesis (e.g., synthesizing and collaborating, and evaluation (e.g., comparing, criticizing, and convincing of information from the presented marine biology problem. Consequently, students were able to effectively design experiments to address the presented issue through problem-based learning. Results of the study show that PBL is an efficient instructional strategy embedded within a conventional curriculum used to develop or enhance critical thinking in marine biology.

Facile synthesis and antimicrobial evaluation of some new heterocyclic compounds incorporating a biologically active sulfamoyl moiety.

Science.gov (United States)

Darwish, Elham S

2014-01-01

A facile and convenient synthesis of new heterocyclic compounds containing a sulfamoyl moiety suitable for use as antimicrobial agents was reported. The precursor 3-oxo-3-phenyl-N-(4-sulfamoylphenyl)propionamide was coupled smoothly with arenediazonium salt producing hydrazones which reacted with malononitrile or triethylorthoformate affording pyridazine and triazine derivatives, respectively. Also, the reactivity of the same precursor with DMF-DMA was followed by aminotriazole; aromatic aldehydes was followed by hydrazine hydrate, triethylorthoformate, or thiourea affording triazolo[1,5-a]pyrimidine, pyrazole, acrylamide, and dihydropyrimidine derivatives, respectively. On the other hand, treatment of the precursor propionamide with phenyl isothiocyanate and KOH in DMF afforded the intermediate salt which was treated with dilute HCl followed by 2-bromo-1-phenylethanone affording carboxamide derivative. While the same intermediate salt reacted in situ with chloroacetone, ethyl 2-chloroacetate, 3-(2-bromoacetyl)-2H-chromen-2-one, methyl iodide, or 2-oxo-N-phenylpropane hydrazonoyl chloride afforded the thiophene, ketene N,S-acetal, and thiadiazole derivatives, respectively. The structure of the new products was established based on elemental and spectral analysis. Antimicrobial evaluation of some selected examples from the synthesized products was carried out whereby four compounds were found to have moderate activities and one compound showed the highest activity.

Synthesis, evaluation and application of radioiodine labeled compounds in nuclear medicine

International Nuclear Information System (INIS)

Ahmed, M. O. M.

2006-01-01

This study reviews synthesis, evaluation,diagnostic and therapeutic applications of iodine radiopharmaceutical especially with 13I I and 123 I in contemporary nuclear medicine. It is well Known that iodine is used in thyroid diagnostic and therapy with sodium iodide and played an important role in diagnostic procedures using single photon emission tomography (SPECT). The study covers the general chemistry of iodine, physical properties, biological role of iodine, general uses of iodine compounds , production and decay schemes of 131 I, 125 I and 123 I in the first chapter. Preparation of radioiodine labeled compounds, quality control of radiopharmaceuticals and safety of radioiodination are dealt with in detail in two chapters. These were followed by chapters dealing in length with the chemistry, preparation, quality control, pharmacokinetics and radiation dosimetry of some iodine radiopharmaceuticals, and then current trends in diagnostic and therapeutic applications of iodine radiopharmaceuticals particularly 131 / 123 I-MIBG and 123 I-IMP. We found that the iodine radiopharmaceuticals are considered amongst principal indicators in single photon emission tomography (SPECT), and 131 / 123 I-MIBG and 123 I-IMP appear to be appropriate diagnostic and therapeutic agents for variety of diseases.(Author)

Eco-friendly synthesis, physicochemical studies, biological assay and molecular docking of steroidal oxime-ethers

Science.gov (United States)

Alam, Mahboob; Lee, Dong-Ung

2015-01-01

The aim of this study was to report the synthesis of biologically active compounds; 7-(2′-aminoethoxyimino)-cholest-5-ene (4), a steroidal oxime-ether and its derivatives (5, 6) via a facile microwave assisted solvent free reaction methodology. This new synthetic, eco-friendly, sustainable protocol resulted in a remarkable improvement in the synthetic efficiency (85-93 % yield) and high purity using basic alumina. The synthesized compounds were screened for their antibacterial against six bacterial strains by disc diffusion method and antioxidant potential by DPPH assay. The binding capabilities of a compound 6 exhibiting good antibacterial potential were assessed on the basis of molecular docking studies and four types of three-dimensional molecular field descriptors. Moreover the structure-antimicrobial activity relationships were studied using some physicochemical and quantum-chemical parameters with GAMESS interface as well as WebMO Job Manager by using the basic level of theory. Hence, this synthetic approach is believed to provide a better scope for the synthesis of steroidal oxime-ether analogues and will be a more practical alternative to the presently existing procedures. Moreover, detailed in silico docking studies suggested the plausible mechanism of steroidal oxime-ethers as effective antimicrobial agents. PMID:27330525

The biology of milk synthesis from a proteomics perspective

NARCIS (Netherlands)

Lu, J.

2013-01-01

Large variation in bovine milk composition of Dutch Holstein cows has been observed. The factors influencing the milk synthesis and secretion process in the mammary gland and the variations in this process lead to variation in milk composition. The understanding of milk synthesis was improved

Synthesis and biological evaluation of glycogen synthase kinase 3 (GSK-3) inhibitors: an fast and atom efficient access to 1-aryl-3-benzylureas.

Science.gov (United States)

Monte, Fabio Lo; Kramer, Thomas; Boländer, Alexander; Plotkin, Batya; Eldar-Finkelman, Hagit; Fuertes, Ana; Dominguez, Juan; Schmidt, Boris

2011-09-15

The glycogen synthase kinase 3 (GSK-3) is implicated in multiple cellular processes and has been linked to the pathogenesis of Alzheimer's disease (AD). In the course of our research topic we synthesized a library of potent GSK-3 inhibitors. We utilized the urea scaffold present in the potent and highly selective GSK-3 inhibitor AR-A014418 (AstraZeneca). This moiety suits both (a) a convergent approach utilizing readily accessible building blocks and (b) a divergent approach based on a microwave heating assisted Suzuki coupling. We established a chromatography-free purification method to generate products with sufficient purity for the biological assays. The structure-activity relationship of the library provided the rationale for the synthesis of the benzothiazolylurea 66 (IC(50)=140 nM) and the pyridylurea 62 (IC(50)=98 nM), which displayed two to threefold enhanced activity versus the reference compound 18 (AR-A014418: IC(50)=330 nM) in our assays. Copyright © 2011. Published by Elsevier Ltd.

Continuous Vigilance - Evaluating Preparedness for a Biological Event

Directory of Open Access Journals (Sweden)

Bruria eAdini

2014-04-01

Full Text Available Objective: Effective response to biological events necessitates ongoing evaluation of preparedness. This study was a bilateral German-Israeli collaboration aimed at developing an evaluation tool for assessing preparedness of medical facilities for biological events.Methods: Measurable parameters were identified through a literature review for inclusion in the evaluation tool and disseminated to 228 content experts in 2 modified Delphi cycles. Focus groups were conducted to identify psychosocial needs of the medical teams. Table top and functional exercises were implemented to review applicability of the tool. Results: 117 experts from Germany and Israel participated in the modified Delphi. Out of 188 parameters that were identified, 183 achieved a consensus of >75% of the content experts. Following comments recommended in the Delphi cycles, and feedback from focus groups and hospital exercises, the final tool consisted of 172 parameters. Median level of importance of each parameter was calculated based on ranking recommended in the Delphi process. Computerized web-based software was developed to calculate scores of preparedness for biological events.Conclusions: Ongoing evaluation means, such as the tool developed in the study, can facilitate the need for a valid and reliable mechanism that may be widely adopted and implemented as quality assurance measures. The tool is based on measurable parameters and indicators that can effectively present strengths and weaknesses in managing a response to a public health threat, and accordingly, steps can be implemented to improve readiness. Adoption of such a tool is an important component of assuring public health and effective emergency management.Contact person regarding the evaluation tool: adinib@bgu.ac.ilLink to the computerized tool: http://www.be-prep.com/us

Design, Synthesis and Evaluation of Ribose-modified Anilinopyrimidine Derivatives as EGFR Tyrosine Kinase Inhibitors

Science.gov (United States)

Hu, Xiuqin; Wang, Disha; Tong, Yi; Tong, Linjiang; Wang, Xia; Zhu, Lili; Xie, Hua; Li, Shiliang; Yang, You; Xu, Yufang

2017-11-01

The synthesis of a series of ribose-modified anilinopyrimidine derivatives was efficiently achieved by utilizing DBU or tBuOLi-promoted coupling of ribosyl alcohols with 2,4,5-trichloropyrimidine as key step. Preliminary biological evaluation of this type of compounds as new EGFR tyrosine kinase inhibitors for combating EGFR L858R/T790M mutant associated with drug resistance in the treatment of non-small cell lung cancer revealed that 3-N-acryloyl-5-O-anilinopyrimidine ribose derivative 1a possessed potent and specific inhibitory activity against EGFR L858R/T790M over WT EGFR. Based upon molecular docking studies of the binding mode between compound 1a and EGFR, the distance between the Michael receptor and the pyrimidine scaffold is considered as an important factor for the inhibitory potency and future design of selective EGFR tyrosine kinase inhibitors against EGFR L858R/T790M mutants.

Evaluating the impact of a Biology I professional development series

Science.gov (United States)

Sampsell, Jacquelyn Scipper

2005-11-01

Effective professional development offers opportunities for teachers to reflect on their practices, modify and implement changes in the classroom, and eventually impact students' learning. However, professional development must be evaluated to determine whether the desired results are actually occurring in the classroom. The Program for Research and Evaluation for Public Schools, Inc. (PREPS) created a Biology I Workshop series to assist school districts in Mississippi in aligning curriculum, instruction, and assessment that will ultimately improve student achievement in the classroom and performance on the current high-stakes test. This study evaluated the PREPS Biology I Subject Area workshops by using Thomas Guskey's evaluation model as a guide for the process. This study used a mixed-method design and collected data from three primary sources: the PREPS Final Evaluation Form completed at the conclusion of workshops, a questionnaire created by the researcher, and interviews with six-case study teacher participants selected from the results of the questionnaire. According to the ratings and comments written on the two instruments and supporting evidence from the case-study teachers, the participants of the Biology I workshop found the workshops to be effective for all five levels of Guskey's evaluation model. The content was rated effective because the workshop materials were aligned to the curriculum frameworks and were focused on using student learning to improve student achievement. Working through the activities rather than simply being told about them and having a successful classroom biology teacher as a presenter were the factors that contributed to the increase in the participants' knowledge and skills. Organizational results indicate that the workshop was effective in that the goals of the workshop series aligned with the schools' mission and goals for student learning. Several issues, such as financial support, time for collaboration with peers, and

Total Synthesis of Natural Products of Microbial Origins(Recent Topics of the Agricultunal Biological Science in Tohoku University)

OpenAIRE

Hiromasa, KIYOTA; Shigefumi, KUWAHARA; Laboratory of Applied Bioorganic Chemistry, Division of Bioscience & Biotechnology for Future Bioindustries, Graduate School of Agricultural Science, Tohoku University; Laboratory of Applied Bioorganic Chemistry, Division of Bioscience & Biotechnology for Future Bioindustries, Graduate School of Agricultural Science, Tohoku University

2008-01-01

Microorganisms are an important rich source of secondary metabolites, which could be useful leads to valuable agrochemicals and/or medicinal drugs. This mini-review describes our recent achievements on the total synthesis of biologically active natural products of microbial origins: pteridic acids A and B (strong plant growth promoters), epoxyquinols A and B (anti-angiogenic compounds), communiols A-F, G, and H, and macrotetrolide α (antibiotics), pyricuol and tabtoxinine-β-lactam (phytotoxin...

Interfacing theories of program with theories of evaluation for advancing evaluation practice: Reductionism, systems thinking, and pragmatic synthesis.

Science.gov (United States)

Chen, Huey T

2016-12-01

Theories of program and theories of evaluation form the foundation of program evaluation theories. Theories of program reflect assumptions on how to conceptualize an intervention program for evaluation purposes, while theories of evaluation reflect assumptions on how to design useful evaluation. These two types of theories are related, but often discussed separately. This paper attempts to use three theoretical perspectives (reductionism, systems thinking, and pragmatic synthesis) to interface them and discuss the implications for evaluation practice. Reductionism proposes that an intervention program can be broken into crucial components for rigorous analyses; systems thinking view an intervention program as dynamic and complex, requiring a holistic examination. In spite of their contributions, reductionism and systems thinking represent the extreme ends of a theoretical spectrum; many real-world programs, however, may fall in the middle. Pragmatic synthesis is being developed to serve these moderate- complexity programs. These three theoretical perspectives have their own strengths and challenges. Knowledge on these three perspectives and their evaluation implications can provide a better guide for designing fruitful evaluations, improving the quality of evaluation practice, informing potential areas for developing cutting-edge evaluation approaches, and contributing to advancing program evaluation toward a mature applied science. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation Of Webquest In Biology:Teachers’ Perception

Directory of Open Access Journals (Sweden)

Kamisah OSMAN

2014-01-01

Full Text Available Teaching and learning based on web or web-based learning is a concept which integrates information and technology in education. Teachers and instructors have to assist their learners to learn to function in this information environment. However, teacher trainers and instructors have limited experience in the integration of ICT by using web in their teaching, mainly for Biology subject. The Indonesian Ministry of Education has started to implement ICT in the process of learning and teaching. Hence, it geared our attention to evaluate the suitability of WebQuest to be used in teacher training among Biology teachers in central Kalimantan. Results showed those teachers’ perceptions towards WebQuest on technical, content, as well as teaching and learning structure were on the high level. However, there was no significant difference on teachers’ perception towards WebQuest based on their experience. Further evaluation study should be done on students to gauge their perception towards the WebQuest.

Synthesis and evaluation of potential ligands for nuclear waste processing

NARCIS (Netherlands)

Iqbal, M.

2012-01-01

The research presented in this thesis deals with the synthesis and evaluation of new potential ligands for the complexation of actinide and lanthanide ions either for their extraction from bulk radioactive waste or their stripping from an extracted organic phase for final processing of the waste. In

Polyunsaturated fatty acid amides from the Zanthoxylum genus - from culinary curiosities to probes for chemical biology.

Science.gov (United States)

Chruma, Jason J; Cullen, Douglas J; Bowman, Lydia; Toy, Patrick H

2018-01-25

Covering up to February 2017The pericarps of several species from the Zanthoxylum genus, a.k.a. the "prickly ash", have long been used for culinary purposes throughout Asia, most notably in the Sichuan (previously Szechuan) cuisine of Southwestern China, due to the unique tingling and numbing orosensations arising from a collection of polyunsaturated fatty acid amide (alkamide) constituents. The past decade has experienced dramatically increased academic and industrial interest in these pungent Zanthoxylum-derived alkamides, with a concomitant explosion in studies aimed at elucidating the specific biochemical mechanisms behind several medically-relevant biological activities exhibited by the natural products. This rapid increase in interest is partially fueled by advances in organic synthesis reported within the past few years that finally have allowed for the production of diastereomerically-pure Zanthoxylum alkamides and related analogs in multigram quantities. Herein is a comprehensive review of the discovery, total synthesis, and biological evaluation of Zanthoxylum-derived polyunsaturated fatty acid amides and synthetic analogues. Critical insights into how chemical synthesis can further benefit future chemical biology efforts in the field are also provided.

Biomimetic and Bioinspired Synthesis of Nanomaterials/Nanostructures.

Science.gov (United States)

Zan, Guangtao; Wu, Qingsheng

2016-03-16

In recent years, due to its unparalleled advantages, the biomimetic and bioinspired synthesis of nanomaterials/nanostructures has drawn increasing interest and attention. Generally, biomimetic synthesis can be conducted either by mimicking the functions of natural materials/structures or by mimicking the biological processes that organisms employ to produce substances or materials. Biomimetic synthesis is therefore divided here into "functional biomimetic synthesis" and "process biomimetic synthesis". Process biomimetic synthesis is the focus of this review. First, the above two terms are defined and their relationship is discussed. Next different levels of biological processes that can be used for process biomimetic synthesis are compiled. Then the current progress of process biomimetic synthesis is systematically summarized and reviewed from the following five perspectives: i) elementary biomimetic system via biomass templates, ii) high-level biomimetic system via soft/hard-combined films, iii) intelligent biomimetic systems via liquid membranes, iv) living-organism biomimetic systems, and v) macromolecular bioinspired systems. Moreover, for these five biomimetic systems, the synthesis procedures, basic principles, and relationships are discussed, and the challenges that are encountered and directions for further development are considered. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Recent Progress in Chemical and Chemoenzymatic Synthesis of Carbohydrates

Science.gov (United States)

Muthana, Saddam; Cao, Hongzhi; Chen, Xi

2011-01-01

Summary The important roles that carbohydrates play in biological processes and their potential application in diagnosis, therapeutics, and vaccine development have made them attractive synthetic targets. Despite ongoing challenges, tremendous progresses have been made in recent years for the synthesis of carbohydrates. The chemical glycosylation methods have become more sophisticated and the synthesis of oligosaccharides has become more predictable. Simplified one-pot glycosylation strategy and automated synthesis are increasingly used to obtain biologically important glycans. On the other hand, chemoenzymatic synthesis continues to be a powerful alternative for obtaining complex carbohydrates. This review highlights recent progress in chemical and chemoenzymatic synthesis of carbohydrates with a particular focus on the methods developed for the synthesis of oligosaccharides, polysaccharides, glycolipids, and glycosylated natural products. PMID:19833544

Ammonia synthesis at low temperatures

DEFF Research Database (Denmark)

Rod, Thomas Holm; Logadottir, Ashildur; Nørskov, Jens Kehlet

2000-01-01

have been carried out to evaluate its feasibility. The calculations suggest that it might be possible to catalytically produce ammonia from molecular nitrogen at low temperatures and pressures, in particular if energy is fed into the process electrochemically. (C) 2000 American Institute of Physics.......Density functional theory (DFT) calculations of reaction paths and energies for the industrial and the biological catalytic ammonia synthesis processes are compared. The industrial catalyst is modeled by a ruthenium surface, while the active part of the enzyme is modeled by a MoFe6S9 complex...

Synthetic biology and metabolic engineering.

Science.gov (United States)

Stephanopoulos, Gregory

2012-11-16

Metabolic engineering emerged 20 years ago as the discipline occupied with the directed modification of metabolic pathways for the microbial synthesis of various products. As such, it deals with the engineering (design, construction, and optimization) of native as well as non-natural routes of product synthesis, aided in this task by the availability of synthetic DNA, the core enabling technology of synthetic biology. The two fields, however, only partially overlap in their interest in pathway engineering. While fabrication of biobricks, synthetic cells, genetic circuits, and nonlinear cell dynamics, along with pathway engineering, have occupied researchers in the field of synthetic biology, the sum total of these areas does not constitute a coherent definition of synthetic biology with a distinct intellectual foundation and well-defined areas of application. This paper reviews the origins of the two fields and advances two distinct paradigms for each of them: that of unit operations for metabolic engineering and electronic circuits for synthetic biology. In this context, metabolic engineering is about engineering cell factories for the biological manufacturing of chemical and pharmaceutical products, whereas the main focus of synthetic biology is fundamental biological research facilitated by the use of synthetic DNA and genetic circuits.

Synthesis of organic compounds 15 N enriched

International Nuclear Information System (INIS)

Oliveira, Claudineia Raquel de; Bendassolli, Jose Albertino; Prestes, Clelber Vieira; Tavares, Glauco Arnold

2002-01-01

The aim of this work was to develop urea- 15 N and glycine- 15 N synthesis for agronomic and biological studies. The production of these compounds was evaluated due to the fact of increasing use of urea, comparing to others solid fertilizers and the importance of glycine in the studies of protein metabolism. A non-conventional method was carried out to synthesize urea. The process involved reaction among Co, NH 3 anidrid and S at low temperature (100 deg C) and of pressure (0,81 mPa) compared to the conventional method. Monolise halets reaction was carried out for glycine synthesis with chloroacetic and ammonia 2 deg C. Both compounds are economic viable, they can be produced at a lower price than the trade market one. (author)

Synthesis and biological evaluation of p,p'-dideuteriophenytoin

Energy Technology Data Exchange (ETDEWEB)

Poupaert, J.H.; Guiot, P.; Dumont, P.

1988-01-01

A reaction sequence is described to synthesize p,p'-dideuteriophenytoin in three steps from commercially available starting materials. The deuterium content at best reached 99.2% as measured by mass spectrometry. For materials with isotopic content up to 95%, excellent agreement was found between the data obtained by mass spectrometry and /sup 13/C-nuclear magnetic resonance operated in a NOE-suppression mode. p,p'-Dideuteriophenytoin was evaluated comparatively with phenytoin and p-deuteriophenytoin in the maximal electroshock test. While all three compounds exhibited a high degree of antiepileptic activity, none of them demonstrated significant superiority over the others.

Design, Synthesis, and Biological Evaluation of Small, High-Affinity Siglec-7 Ligands: Toward Novel Inhibitors of Cancer Immune Evasion.

Science.gov (United States)

Prescher, Horst; Frank, Martin; Gütgemann, Stephan; Kuhfeldt, Elena; Schweizer, Astrid; Nitschke, Lars; Watzl, Carsten; Brossmer, Reinhard

2017-02-09

Natural killer cells are able to directly lyse tumor cells, thereby participating in the immune surveillance against cancer. Unfortunately, many cancer cells use immune evasion strategies to avoid their eradication by the immune system. A prominent escape strategy of malignant cells is to camouflage themselves with Siglec-7 ligands, thereby recruiting the inhibitory receptor Siglec-7 expressed on the NK cell surface which subsequently inhibits NK-cell-mediated lysis. Here we describe the synthesis and evaluation of the first, high-affinity low molecular weight Siglec-7 ligands to interfere with cancer cell immune evasion. The compounds are Sialic acid derivatives and bind with low micromolar K d values to Siglec-7. They display up to a 5000-fold enhanced affinity over the unmodified sialic acid scaffold αMe Neu5Ac, the smallest known natural Siglec-7 ligand. Our results provide a novel immuno-oncology strategy employing natural immunity in the fight against cancers, in particular blocking Siglec-7 with low molecular weight compounds.

Biological synthesis of silver nanoparticles

International Nuclear Information System (INIS)

Maliszewska, I; Szewczyk, K; Waszak, K

2009-01-01

Fungus-mediated synthesis of silver nanoparticles is reported. The nanosilver was formed in contact with the cell-free filtrate of Penicillium strain studied. The nanoparticles were characterized by means of the UV-Vis spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The synthesized nanosilver showed a absorbed maximum at 425 nm in the visible region. The SEM characterization of the fungus cells treated with silver nitrite indicated that the protein might be responsible for the reduction of silver ions. Transmission electron microscopy (TEM) micrograph showed formation of silver nanoparticles in the range of 10-100 nm.

Synthesis and biological evaluation of S-acyl-3-thiopropyl prodrugs of N-phosphonoacetyl-L-aspartate (PALA).

Science.gov (United States)

Gagnard, Valérie; Leydet, Alain; Le Mellay, Véronique; Aubenque, Marielle; Morère, Alain; Montero, Jean-Louis

2003-10-01

The synthesis of new prodrugs of PALA characterised by the presence of S-acyl-3-thiopropyl, as enzyme-labile groups on the phosphonate moiety of PALA, is reported. The cytotoxic activities of PALA prodrugs were determined against human cell line (SW1573 lung carcinoma cells). A number of prodrugs bearing S-pivaloyl as acyl groups displayed cytotoxic activity in the same order of magnitude of PALA.

“Miswak” Based Green Synthesis of Silver Nanoparticles: Evaluation and Comparison of Their Microbicidal Activities with the Chemical Synthesis

Directory of Open Access Journals (Sweden)

Mohammed Rafi Shaik

2016-11-01

Full Text Available Microbicidal potential of silver nanoparticles (Ag-NPs can be drastically improved by improving their solubility or wettability in the aqueous medium. In the present study, we report the synthesis of both green and chemical synthesis of Ag-NPs, and evaluate the effect of the dispersion qualities of as-prepared Ag-NPs from both methods on their antimicrobial activities. The green synthesis of Ag-NPs is carried out by using an aqueous solution of readily available Salvadora persica L. root extract (RE as a bioreductant. The formation of highly crystalline Ag-NPs was established by various analytical and microscopic techniques. The rich phenolic contents of S. persica L. RE (Miswak not only promoted the reduction and formation of NPs but they also facilitated the stabilization of the Ag-NPs, which was established by Fourier transform infrared spectroscopy (FT-IR analysis. Furthermore, the influence of the volume of the RE on the size and the dispersion qualities of the NPs was also evaluated. It was revealed that with increasing the volume of RE the size of the NPs was deteriorated, whereas at lower concentrations of RE smaller size and less aggregated NPs were obtained. During this study, the antimicrobial activities of both chemically and green synthesized Ag-NPs, along with the aqueous RE of S. persica L., were evaluated against various microorganisms. It was observed that the green synthesized Ag-NPs exhibit comparable or slightly higher antibacterial activities than the chemically obtained Ag-NPs.

Opuntia ficus indica peel derived pectin mediated hydroxyapatite nanoparticles: Synthesis, spectral characterization, biological and antimicrobial activities

Science.gov (United States)

Gopi, D.; Kanimozhi, K.; Kavitha, L.

2015-04-01

In the present study, we have adapted a facile and efficient green route for the synthesis of HAP nanoparticles using pectin as a template which was extracted from the peel of prickly pear (Opuntia ficus indica) fruits. The concentration of pectin plays a major role in the behavior of crystallinity, purity, morphology as well as biological property of the as-synthesized HAP nanoparticles. The extracted pectin and the as-synthesized nanoparticles were characterized by various analytical techniques. The in vitro apatite formation on the surface of the as-synthesized nanoparticles in simulated body fluid (SBF) for various days showed an enhanced bioactivity. Also, the antimicrobial activity was investigated using various microorganisms. All the results revealed the formation of pure, low crystalline and discrete granular like HAP nanoparticles of size around 25 nm with enhanced biological and antimicrobial activities. Hence the as-synthesized nanoparticles can act as a better bone regenerating material in the field of biomedicine.

Opuntia ficus indica peel derived pectin mediated hydroxyapatite nanoparticles: synthesis, spectral characterization, biological and antimicrobial activities.

Science.gov (United States)

Gopi, D; Kanimozhi, K; Kavitha, L

2015-04-15

In the present study, we have adapted a facile and efficient green route for the synthesis of HAP nanoparticles using pectin as a template which was extracted from the peel of prickly pear (Opuntia ficus indica) fruits. The concentration of pectin plays a major role in the behavior of crystallinity, purity, morphology as well as biological property of the as-synthesized HAP nanoparticles. The extracted pectin and the as-synthesized nanoparticles were characterized by various analytical techniques. The in vitro apatite formation on the surface of the as-synthesized nanoparticles in simulated body fluid (SBF) for various days showed an enhanced bioactivity. Also, the antimicrobial activity was investigated using various microorganisms. All the results revealed the formation of pure, low crystalline and discrete granular like HAP nanoparticles of size around 25 nm with enhanced biological and antimicrobial activities. Hence the as-synthesized nanoparticles can act as a better bone regenerating material in the field of biomedicine. Copyright © 2015 Elsevier B.V. All rights reserved.

Gas Phase Nanoparticle Synthesis

Science.gov (United States)

Granqvist, Claes; Kish, Laszlo; Marlow, William

This book deals with gas-phase nanoparticle synthesis and is intended for researchers and research students in nanomaterials science and engineering, condensed matter physics and chemistry, and aerosol science. Gas-phase nanoparticle synthesis is instrumental to nanotechnology - a field in current focus that raises hopes for environmentally benign, resource-lean manufacturing. Nanoparticles can be produced by many physical, chemical, and even biological routes. Gas-phase synthesis is particularly interesting since one can achieve accurate manufacturing control and hence industrial viability.

Biological synthesis and characterization of silver nanoparticles ...

Indian Academy of Sciences (India)

or less have engrossed great attention due to their unusual and captivating ... ical method of nanoparticles synthesis using microorgan- isms, enzyme and plant or plant .... mined using Student's t-test with two-way Anova was set at p ≤ 0.05. 3.

Evaluation of Potential Biological Threats in Ukraine

International Nuclear Information System (INIS)

Pozdnyakova, L.; Slavina, N.; Pozdnyakov, S.

2007-01-01

Dilating of biological threats spectrum, EDI diffusion opportunities and routes, unpredictability of outbreaks connected with connatural, technogenic, terrorist factors determines constant monitoring and readiness for operative BPA indication and identification. Scientific analytical approach of existing and probable regional bio-threats evaluation is necessary for adequate readiness system creation and maintenance of medical counteraction tactics to probable biological threats. Basing on the international experience, we carry out analysis of a situation present in Ukraine and routes for the decisions. The basic directions are: - Evaluation of a reality for EDI penetration from abroad and presence of conditions for their further diffusion inside the country. - Revealing of presence and definition of connatural EDI foci biocenoses features and BPAs. - Appropriate level of biological safety and physical protection of bio-laboratories and pathogens collections maintenance. - Gene/molecular and phenotypical definition of EDI circulating strains. - Creation of the circulating EDI gene/ phenotypic characteristics regional data bank. - Ranging of EDI actual for area. - Introduction of GPT, mathematical modeling and forecasting for tactics development in case of technogenic accidents and connatural outbreaks. - Methodical basis and equipment improvement for BPA system indication for well-timed identification of natural, or modified agent. - Education and training The international cooperation in maintenance of biosafety and bioprotection within the framework of scientific programs, grants, exchange of experience, introduction of international standards and rules are among basic factors in the decision for creating system national biosafety for countries not included in EU and the NATO. (author)

Biological evaluation of silver nanoparticles incorporated into chitosan-based membranes

NARCIS (Netherlands)

Shao, J.; Yu, N.; Kolwijck, E.; Wang, B.; Tan, K.W.; Jansen, J.A.; Walboomers, X.F.; Yang, F.

2017-01-01

AIM: To evaluate the antibacterial potential and biological performance of silver nanoparticles in chitosan-based membranes. MATERIALS & METHODS: Electrospun chitosan/poly(ethylene oxide) membranes with different amounts of silver nanoparticles were evaluated for antibacterial properties and

Novel 1,2-dihydroquinazolin-2-ones: Design, synthesis, and biological evaluation against Trypanosoma brucei.

Science.gov (United States)

Pham, ThanhTruc; Walden, Madeline; Butler, Christopher; Diaz-Gonzalez, Rosario; Pérez-Moreno, Guiomar; Ceballos-Pérez, Gloria; Gomez-Pérez, Veronica; García-Hernández, Raquel; Zecca, Henry; Krakoff, Emma; Kopec, Brian; Ichire, Ogar; Mackenzie, Caden; Pitot, Marika; Ruiz, Luis Miguel; Gamarro, Francisco; González-Pacanowska, Dolores; Navarro, Miguel; Dounay, Amy B

2017-08-15

In 2014, a published report of the high-throughput screen of>42,000 kinase inhibitors from GlaxoSmithKline against T. brucei identified 797 potent and selective hits. From this rich data set, we selected NEU-0001101 (1) for hit-to-lead optimization. Through our preliminary compound synthesis and SAR studies, we have confirmed the previously reported activity of 1 in a T. brucei cell proliferation assay and have identified alternative groups to replace the pyridyl ring in 1. Pyrazole 24 achieves improvements in both potency and lipophilicity relative to 1, while also showing good in vitro metabolic stability. The SAR developed on 24 provides new directions for further optimization of this novel scaffold for anti-trypanosomal drug discovery. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evaluation of the Redesign of an Undergraduate Cell Biology Course

Science.gov (United States)

McEwen, Laura April; Harris, dik; Schmid, Richard F.; Vogel, Jackie; Western, Tamara; Harrison, Paul

2009-01-01

This article offers a case study of the evaluation of a redesigned and redeveloped laboratory-based cell biology course. The course was a compulsory element of the biology program, but the laboratory had become outdated and was inadequately equipped. With the support of a faculty-based teaching improvement project, the teaching team redesigned the…

Particulate Matter Resuspension in Mississippi Bight Evaluated with CONCORDE's Synthesis Model

Science.gov (United States)

O'Brien, S. J.; Quas, L. M.; Miles, T. N.; Pan, C.; Cambazoglu, M. K.; Soto Ramos, I. M.; Greer, A. T.; Church, I.; Wiggert, J. D.

2017-12-01

The CONsortium for oil spill exposure pathways in COastal River-Dominated Ecosystems (CONCORDE) was established to investigate the complex fine-scale biological, chemical and physical interactions in a marine system controlled by pulsed-river plume dynamics. During CONCORDE's spring 2016 field campaign, the In Situ Ichthyoplankton Imaging System (ISIIS) on the R/V Point Sur and the Scanfish on the R/V Pelican comprehensively characterized the physical and biological structure in the region. Increased suspended particulate matter was observed by the ISIIS, with concentrations at depth sufficient to completely occlude the in situ images of planktonic organisms. Data was also collected on the continental shelf during the spring cruise by the RU31 glider in the proximity of the Mississippi River Delta, east of the ISIIS / Scanfish transects. Backscatter and salinity observed by the Scanfish and glider showed elevated suspended particulate matter and increased salinity, suggesting a linkage to shoreward advection from the continental shelf of oceanic waters that are sufficiently energetic to drive sediment resuspension. As part of the CONCORDE research effort, a four-dimensional biogeochemical/lower trophic level synthesis model for Mississippi Sound and Bight has been developed, based on the Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) Modeling System. This study utilizes CONCORDE's synthesis model to investigate the physical forcing mechanisms affecting the increased suspended particulate matter concentration observed in the Mississippi Bight during spring 2016, and advection pathways between estuarine and shelf waters in the northern Gulf of Mexico. The results show that episodic, advection-driven resuspension is a critical aspect controlling suspended sediment distributions in Mississippi Bight, which has implications for observed spatio-temporal patterns of planktonic species.

Synthesis and evaluation of new protecting agents against ionizing radiations

International Nuclear Information System (INIS)

Nadal, B.

2009-10-01

This thesis is devoted to the synthesis of new pulvinic acid derivatives and the evaluation of their antioxidant and radioprotective properties. This study has been conducted with the aim to develop new protecting agents against ionizing radiations. A new access to pulvinic acid derivatives was developed starting from L-dimethyl tartrate. It is based on a Dieckmann cyclization a dehydration and a Suzuki-Miyaura coupling. It allows a short effective preparation of various pulvinic acid derivatives: tetronic acid derivatives, mono-substituted pulvinic acid derivatives and methyl pulvinates. A modified method has been used to prepare pulvinones. This strategy gave access in four steps to the desired pulvinones. The rapidity of this method is provided by a tandem process, carried out in the final step, involving a Dieckmann cyclization and a β-elimination. A synthesis of 3-aryltetramic acids has also been developed in order to prepare nitrogen derivatives of pulvinic acid. The antioxidant activity of the prepared compounds was then evaluated using various tests: DPPH, ABTS, protection of thymidine and DNA study of lipid peroxidation. These evaluations allowed to define interesting structure-activity relationships of pulvinic derivatives. They have shown that several derivatives have very good antioxidant activities. Finally, radioprotective tests on TK6 cells and mice have have been performed on selected compounds. (author)

Physio-chemical evaluation and biological activity of Ajuga ...

African Journals Online (AJOL)

Physio-chemical evaluation and biological activity of Ajuga bracteosa wall and Viola odoroto Linn. Anwar Ali Shad, M. Zeeshan, Hina Fazal, Hamid Ullah Shah, Shabir Ahmed, Hasem Abeer, E. F. Abd_Allah, Riaz Ullah, Hamid Afridi, Akash tariq, Muhammad Adnan Asma ...

Function-oriented synthesis: biological evaluation of laulimalide analogues derived from a last step cross metathesis diversification strategy.

Science.gov (United States)

Mooberry, Susan L; Hilinski, Michael K; Clark, Erin A; Wender, Paul A

2008-01-01

Laulimalide is a potent microtubule stabilizing agent and a promising anticancer therapeutic lead. The identification of stable, efficacious and accessible analogues is critical to clinically exploiting this novel lead. To determine which structural features of laulimalide are required for beneficial function and thus for accessing superior clinical candidates, a series of side chain analogues were prepared through a last step cross metathesis diversification strategy and their biological activities were evaluated. Five analogues, differing in potency from 233 nM to 7.9 muM, effectively inhibit cancer cell proliferation. Like laulimalide, they retain activity against multidrug resistant cells, stabilize microtubules and cause the formation of aberrant mitotic spindles, mitotic accumulation, Bcl-2 phosphorylation and initiation of apoptosis. Structural modifications in the C 23-C 27 dihydropyran side chain can be made without changing the overall mechanism of action, but it is clear that this subunit has more than a bystander role.

SELECTIVE C-2 AND C-4 DEACYLATION AND ACYLATION OF TAXOL - THE FIRST SYNTHESIS OF A C-4 SUBSTITUTED TAXOL ANALOG

DEFF Research Database (Denmark)

GEORG, GI; ALI, SM; BOGE, TC

1994-01-01

Hydrolytic procedures for selective 2-debenzoylation and 2,4-dideacylation of 2'-0-tert-butyldimethylsilyl-7-0-(triethylsilyl)taxol are reported. The first synthesis and biological evaluation of a 4-substituted analogue, 4-deacetyl-4-isobutanoyltaxol, is presented. The chemistry described in this...... in this letter is suitable for the facile synthesis of taxol congeners modified at C-2 and/or C-4....

Towards the synthesis of an experimental bioactive dental ceramic. Part I: Crystallinity characterization and bioactive behavior evaluation

International Nuclear Information System (INIS)

Goudouri, O.-M.; Kontonasaki, E.; Papadopoulou, L.; Kantiranis, N.; Lazaridis, N.K.; Chrissafis, K.; Chatzistavrou, X.; Koidis, P.; Paraskevopoulos, K.M.

2014-01-01

An attachment between the dental ceramic and the surrounding marginal tissues in fixed prosthetic restorations could eliminate secondary carries prevalence. The development of dental ceramics with apatite forming ability could provide the biological surface required for selective spread and attachment of specific cell types able to promote tissue attachment. Dental ceramics/bioactive glass composites synthesized by the sol gel method have been previously reported to develop carbonated hydroxyapatite (HCAp) in biomimetic solutions, requiring though a high amount of bioactive glass, which resulted in the compromise of their mechanical integrity. Thus, the aim of the present work was the synthesis and characterization of an experimental sol–gel derived dental ceramic with low amount of bioactive glass and the evaluation of its in vitro bioactivity. Differential thermal and thermogravimetric analysis (TG–DTA), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffractometry (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) were used to evaluate the crystal structure and the in vitro apatite forming ability of the synthesized material. The results of this study indicated the successful sol–gel synthesis of an experimental dental ceramic containing low amount of bioactive glass that presented similar structural and morphological characteristics with a commercial feldspathic dental ceramic, while exhibiting in vitro bioactivity. The apatite forming ability of the experimental sol–gel derived feldspathic dental ceramic may trigger the appropriate cellular mechanisms towards the establishment of attachment with the surrounding connective tissue. This attachment could provide a barrier to oral bacteria penetration, prolonging the life expectation of the restorations. - Highlights: • Synthesis of a bioactive sol–gel dental ceramic for fixed prosthetic restorations. • The sol–gel technique promoted the crystallization of

Towards the synthesis of an experimental bioactive dental ceramic. Part I: Crystallinity characterization and bioactive behavior evaluation

Energy Technology Data Exchange (ETDEWEB)

Goudouri, O.-M. [Physics Department, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Kontonasaki, E. [School of Dentistry, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Papadopoulou, L.; Kantiranis, N. [Department of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Lazaridis, N.K. [Chemistry Department, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Chrissafis, K.; Chatzistavrou, X. [Physics Department, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Koidis, P. [School of Dentistry, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Paraskevopoulos, K.M., E-mail: kpar@auth.gr [Physics Department, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)

2014-05-01

An attachment between the dental ceramic and the surrounding marginal tissues in fixed prosthetic restorations could eliminate secondary carries prevalence. The development of dental ceramics with apatite forming ability could provide the biological surface required for selective spread and attachment of specific cell types able to promote tissue attachment. Dental ceramics/bioactive glass composites synthesized by the sol gel method have been previously reported to develop carbonated hydroxyapatite (HCAp) in biomimetic solutions, requiring though a high amount of bioactive glass, which resulted in the compromise of their mechanical integrity. Thus, the aim of the present work was the synthesis and characterization of an experimental sol–gel derived dental ceramic with low amount of bioactive glass and the evaluation of its in vitro bioactivity. Differential thermal and thermogravimetric analysis (TG–DTA), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffractometry (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) were used to evaluate the crystal structure and the in vitro apatite forming ability of the synthesized material. The results of this study indicated the successful sol–gel synthesis of an experimental dental ceramic containing low amount of bioactive glass that presented similar structural and morphological characteristics with a commercial feldspathic dental ceramic, while exhibiting in vitro bioactivity. The apatite forming ability of the experimental sol–gel derived feldspathic dental ceramic may trigger the appropriate cellular mechanisms towards the establishment of attachment with the surrounding connective tissue. This attachment could provide a barrier to oral bacteria penetration, prolonging the life expectation of the restorations. - Highlights: • Synthesis of a bioactive sol–gel dental ceramic for fixed prosthetic restorations. • The sol–gel technique promoted the crystallization of

Biological evaluation and simple method for the synthesis of tetrahydrobenzo[a]xanthenes-11-one derivatives

Directory of Open Access Journals (Sweden)

Ali Akbari

2017-01-01

Full Text Available A simple method for the synthesis of Tetrahydrobenzo[a]xanthenes-11-one derivatives in the presence of BF3.SiO2, and its antibacterial activity was assessed against Pseudomonas syringae, Xanthomonas citi and Pectobacterium carotovorum. The structure of the isolated compounds has been determined by means of 1H/13C NMR and FT-IR spectroscopy. The reactions were carried out in water at room temperature for 5 h. This method has some advantages such as good to excellent yield, mild reaction condition, ease of operation and workup, high product purity and green process.

Synthesis, biological assessment and molecular modeling of new dihydroquinoline-3-carboxamides and dihydroquinoline-3-carbohydrazide derivatives as cholinesterase inhibitors, and Ca channel antagonists.

Science.gov (United States)

Tomassoli, Isabelle; Ismaili, Lhassane; Pudlo, Marc; de Los Ríos, Cristóbal; Soriano, Elena; Colmena, Inés; Gandía, Luis; Rivas, Luis; Samadi, Abdelouahid; Marco-Contelles, José; Refouvelet, Bernard

2011-01-01

The synthesis, biological evaluation, and molecular modeling of new 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxamides(4), 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carbohydrazide (6), and some hexahydropyrimido[5,4-c]quinoline-2,5-diones (9) produced earlier by our laboratory, as AChE/BuChE inhibitors, is described. From these analyses compound 4c resulted equipotent regarding the inhibition of cholinesterases'; inhibitors 6k, 9a, 9b were selective for AChE, whereas product 4d proved selective for BuChE. Docking analysis has been carry out in order to identify the binding mode in the active site, and to explain the observed selectivities. Only compound 9a has been shown to decrease K(+)-induced calcium signals in bovine chromaffin cells. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Synthesis of biological active thiosemicarbazone and characterization of the interaction with human serum albumin

International Nuclear Information System (INIS)

Yu, Wangshu; Shi, Lei; Hui, Guangquan; Cui, Fengling

2013-01-01

The synthesis of a new biological active reagent, 2-((1,4-dihydroxy)-9,10-anthraquinone) aldehyde thiosemicarbazone (DHAQTS), was designed. The interaction between DHAQTS and HSA was studied by fluorescence spectroscopy in combination with molecular modeling under simulation of physiological conditions. According to the results of fluorescence measurements, the quenching mechanism was suggested to be static. The thermodynamic parameters are calculated by van't Hoff equation, which demonstrated that hydrophobic interactions are the predominant intermolecular forces stabilizing the complex. The number of binding sites (n) was calculated. Through the site marker competitive experiment, DHAQTS was confirmed to be located in site I of HSA. The binding distance r=2.83 nm between the donor HSA and acceptor DHAQTS was obtained according to Förster's non-radiative energy transfer theory. The three-dimensional fluorescence spectral results showed the conformation and microenvironment of HSA changed in the presence of DHAQTS. The effects of common ions on the binding of DHAQTS to HSA were also evaluated. The experimental results were in agreement with the results obtained via a molecular docking study. - Highlights: ► 2-((1,4-dihydroxy)-9,10-anthraquinone)aldehyde thiosemicarbazone (DHAQTS) was synthesized. ► DHAQTS can quench the fluorescence of human serum albumin (HSA) by static quenching mechanism. ► Hydrophobic interactions were the predominant intermolecular forces. ► The competitive experiment was carried out to identify the DHAQTS binding site on HSA. ► Three-dimensional spectra confirmed DHAQTS caused the conformational change of HSA.

An investigation of nitrile transforming enzymes in the chemo-enzymatic synthesis of the taxol sidechain

Czech Academy of Sciences Publication Activity Database

Wilding, B.; Veselá, Alicja Barbara; Perry, J.B.J.; Black, W.G.; Zhang, M.; Martínková, Ludmila; Klempier, N.

2015-01-01

Roč. 13, č. 28 (2015), s. 7803-7812 ISSN 1477-0520 R&D Projects: GA ČR(CZ) GAP504/11/0394 Institutional support: RVO:61388971 Keywords : LIPASE -CATALYZED TRANSESTERIFICATION * HIGHLY ENANTIOSELECTIVE SYNTHESIS * BIOLOGICAL EVALUATION Subject RIV: CC - Organic Chemistry Impact factor: 3.559, year: 2015

Radiolabelled neurotensin analogues. I. Solid phase synthesis and biological characterization of [Trp11]-neurotensin precursor of an ionidated ligand

International Nuclear Information System (INIS)

Labbe-Jullie, C.; Granier, C.; Van Rietschoten, J.; Kitabgi, P.; Vincent, J.P.

1983-01-01

In order to generate highly labelled neurotensin analogues, synthesis has been performed of two types of precursors, one for iodination and one for tritiation. Iodination of native neurotensin occurs on both tyrosines in position 3 and 11 and thus affects greatly its binding capacities. Synthesis and chemical characterization of [Trp 11 ]-neurotensin are described which can be iodinated without loss of activity. Synthesis was by solid phase procedure on an experimental support, Pab-resin, α-(4-chloromethylphenylacetamido)-benzyl copoly (styrene 1 per cent divinylbenzene). The homogeneity of [Trp 11 ]-neurotensin was assessed by amino acid analysis, high voltage paper electrophoresis and high pressure liquid chromatography. Iodination by the lactoperoxydase method gave iodo-[Trp 11 ]-neurotensin iodinated on the Tyr 3 . Compared to neurotensin, potency of [Trp 11 ]-neurotensin and of iodo-[Trp 11 ]-neurotensin in competitive inhibition of tritiated neurotensin binding to rat brain synaptic membranes was respectively 93 per cent and 80 per cent, but in the biological test on the contractility of isolated longitudinal smooth muscle strips of guinea pig the relative activity for the two analogues was of 10 per cent [fr

Biological synthesis and characterization of intracellular gold ...

Indian Academy of Sciences (India)

In the present study, Aspergillus fumigatus was used for the intracellular synthesis of gold nanoparticles. Stable nanoparticles were produced when an aqueous solution of chloroauric acid (HAuCl4) was reduced by A. fumigatus biomass as the reducing agent. Production of nanoparticles was confirmed by the colour ...

Synthetic Methods and Exploring Biological Potential of Various Substituted Quinoxalin-2-one Derivatives

OpenAIRE

Mohammad Asif

2016-01-01

Substituted quinoxaline have considerable interest in chemistry, biology and pharmacology. Quinoxaline derivatives are capable with variety of biological activities and possess different biological activities, of which the most potent are anti-microbial, analgesic and anti-inflammatory activities. It facilitated the researchers to develop various methods for their synthesis and their applications. In this review represented different methods of synthesis, reactivity and various biological act...

Synthesis and antimicrobial evaluation of the new Isoxazole and Pyrazole derivatives

International Nuclear Information System (INIS)

Goda, F.E.; Maarouf, A.R.; El-Bendary, E.R.

2003-01-01

A series of 3-methyl-4-substituted (phenylazo) isoxazolin-5-ones(5a,b),pyrazolin-5-ones (6a-d)and pyrazolidin-3,5-diones(10a-c) have been synthesized and evaluated for their antimicrobial activities.The detailed synthesis , spectroscopic and biogical data are reported. (author)

Design, Synthesis and Evaluation of Novel Phthalimide Derivatives as in Vitro Anti-Microbial, Anti-Oxidant and Anti-Inflammatory Agents

Czech Academy of Sciences Publication Activity Database

Lamie, P.F.; Philoppes, J.N.; El-Gendy, A.O.; Rárová, Lucie; Grúz, Jiří

2015-01-01

Roč. 20, č. 9 (2015), s. 16620-16642 ISSN 1420-3049 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : synthesis * phthalimides * anti-microbial Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.465, year: 2015

Simultaneous removal and evaluation of organic substrates and NH3-N by a novel combined process in treating chemical synthesis-based pharmaceutical wastewater

International Nuclear Information System (INIS)

Chen, Zhaobo; Wang, Hongcheng; Ren, Nanqi; Cui, Minhua; Nie, Shukai; Hu, Dongxue

2011-01-01

Highlights: ► We research a novel combined process to treat chemical synthesis-based pharmaceutical wastewater. ► The mechanism of amoxicillin verifies that the biodegradation, adsorption, hydrolysis and unknown mechanism were able to remove amoxicillin from wastewater. ► In this study demonstrates that biodegradation is the major factor for removal mechanism at work for amoxicillin. ► Mathematical statistic methods were employed to evaluate the performance of the WWTP. - Abstract: A full-scale novel combined anaerobic/micro-aerobic and two-stage aerobic biological process is used for the treatment of an actual chemical synthesis-based pharmaceutical wastewater containing amoxicillin. The anaerobic system is an up-flow anaerobic sludge blanket (UASB), the micro-aerobic system is a novel micro-aerobic hydrolysis acidification reactor (NHAR) and the two-stage aerobic process comprised cyclic activated sludge system (CASS) and biological contact oxidation tank (BCOT). The influent wastewater was high in COD, NH 3 -N varying daily 4016–13,093 mg-COD L −1 and 156.4–650.2 mg-NH 3 -N L −1 , amoxicillin varying weekly between 69.1 and 105.4 mg-amoxicillin L −1 , respectively; Almost all the COD, NH 3 -N, amoxicillin were removed by the biological combined system, with removal percentages 97%, 93.4% and 97.2%, respectively, leaving around 104 mg-COD L −1 , 9.4 mg-NH 3 -N L −1 and 2.6 ± 0.8 mg-amoxicillin L −1 in the final clarifier effluent. The performance evaluation of the wastewater treatment plant (WWTP) by mathematical statistic methods shown that at most of time effluent can meet the higher treatment discharge standard. In addition, the fate of amoxicillin in the full-scale WWTP and the amoxicillin removal rate of each different removal routes in UASB, NHAR, CASS, BCOT and final clarifier processes are investigated in this paper. The results show that biodegradation, adsorption and hydrolysis are the major mechanisms for amoxicillin removal.

In vitro synthesis of biologically active transcripts of tomato black ring virus satellite RNA.

Science.gov (United States)

Greif, C; Hemmer, O; Demangeat, G; Fritsch, C

1990-04-01

Synthetic transcripts of tomato black ring virus satellite RNA (TBRV satRNA), isolate L, were prepared from cDNA cloned in the Bluescribe transcription vector. Transcripts with 49 (T49L) or two (T2GL) extra nucleotides at their 5' ends and 42 extra nucleotides at their 3' ends were able to induce, but to different extents, the synthesis in vitro of the satRNA-encoded 48K protein. However, when inoculated into Chenopodium quinoa together with TBRV L genomic RNAs, only T2GL was biologically active, in the presence or absence of a 5' cap analogue in the transcription reactions. Analysis of the 5' and 3' termini of the satRNA isolated from plants showed that nonviral extensions were not maintained in the transcript progeny.

Microwave-assisted Eco-Friendly Synthesis and Antimicrobial Evaluation of Aryl-Triazole-1,3,4-Thiadiazols

OpenAIRE

Jaiswal, S; Dwivedi, S

2017-01-01

Due to the growing awareness about environmental pollution and environmental legislation, recent years have witnessed a phenomenal increase in the application of microwave irradiation (MW) in organic synthesis. Heterocyclic compounds are abundant in nature and are of great significance to life because their structural subunits exist in many natural products such as vitamins, hormones, and antibiotics; hence, they have attracted considerable attention in the design of biologically active molec...

Synthesis and anticancer evaluation of spermatinamine analogues

KAUST Repository

Moosa, Basem

2016-02-04

Spermatinamine was isolated from an Australian marine sponge, Pseudoceratina sp. as an inhibitor of isoprenylcystiene carboxyl methyltransferase (Icmt), an attractive and novel anticancer target. Herein, we report the synthesis of spermatinamine analogues and their cytotoxic evaluation against three human cancer cell lines i.e. cervix adenocarcinoma (HeLa), breast adenocarcinoma (MCF-7), and prostate carcinoma (DU145). Analogues 12, 14 and 15 were found to be the most potent against one or more cell lines with the IC50 values in the range of 5 - 10 μM. The obtained results suggested that longer polyamine linker along with aromatic oxime substitution provided the most potent analogue compounds against cancer cell lines.

Catalyst synthesis and evaluation using an integrated atomic layer deposition synthesis–catalysis testing tool

International Nuclear Information System (INIS)

Camacho-Bunquin, Jeffrey; Shou, Heng; Marshall, Christopher L.; Aich, Payoli; Beaulieu, David R.; Klotzsch, Helmut; Bachman, Stephen; Hock, Adam; Stair, Peter

2015-01-01

An integrated atomic layer deposition synthesis-catalysis (I-ALD-CAT) tool was developed. It combines an ALD manifold in-line with a plug-flow reactor system for the synthesis of supported catalytic materials by ALD and immediate evaluation of catalyst reactivity using gas-phase probe reactions. The I-ALD-CAT delivery system consists of 12 different metal ALD precursor channels, 4 oxidizing or reducing agents, and 4 catalytic reaction feeds to either of the two plug-flow reactors. The system can employ reactor pressures and temperatures in the range of 10 −3 to 1 bar and 300–1000 K, respectively. The instrument is also equipped with a gas chromatograph and a mass spectrometer unit for the detection and quantification of volatile species from ALD and catalytic reactions. In this report, we demonstrate the use of the I-ALD-CAT tool for the synthesis of platinum active sites and Al 2 O 3 overcoats, and evaluation of catalyst propylene hydrogenation activity

Catalyst synthesis and evaluation using an integrated atomic layer deposition synthesis–catalysis testing tool

Energy Technology Data Exchange (ETDEWEB)

Camacho-Bunquin, Jeffrey; Shou, Heng; Marshall, Christopher L. [Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439 (United States); Aich, Payoli [Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439 (United States); Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60607 (United States); Beaulieu, David R.; Klotzsch, Helmut; Bachman, Stephen [Arradiance Inc., Sudbury, Massachusetts 01776 (United States); Hock, Adam [Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439 (United States); Department of Chemistry, Illinois Institute of Technology, Chicago, Illinois 60616 (United States); Stair, Peter [Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439 (United States); Department of Chemistry, Northwestern University, Evanston, Illinois 60208 (United States)

2015-08-15

An integrated atomic layer deposition synthesis-catalysis (I-ALD-CAT) tool was developed. It combines an ALD manifold in-line with a plug-flow reactor system for the synthesis of supported catalytic materials by ALD and immediate evaluation of catalyst reactivity using gas-phase probe reactions. The I-ALD-CAT delivery system consists of 12 different metal ALD precursor channels, 4 oxidizing or reducing agents, and 4 catalytic reaction feeds to either of the two plug-flow reactors. The system can employ reactor pressures and temperatures in the range of 10{sup −3} to 1 bar and 300–1000 K, respectively. The instrument is also equipped with a gas chromatograph and a mass spectrometer unit for the detection and quantification of volatile species from ALD and catalytic reactions. In this report, we demonstrate the use of the I-ALD-CAT tool for the synthesis of platinum active sites and Al{sub 2}O{sub 3} overcoats, and evaluation of catalyst propylene hydrogenation activity.

Synthesis, biological evaluation and docking studies of 2,3-dihydroquinazolin-4(1H)-one derivatives as inhibitors of cholinesterases.

Science.gov (United States)

Sarfraz, Muhammad; Sultana, Nargis; Rashid, Umer; Akram, Muhammad Safwan; Sadiq, Abdul; Tariq, Muhammad Ilyas

2017-02-01

In search of potent inhibitors of cholinesterases, we have synthesized and evaluate a number of 2,3-dihydroquinazolin-4(1H)-one derivatives. The synthetic approach provided an efficient synthesis of the target molecules with excellent yield. All the tested compounds showed activity against both the enzymes in micromolar range. In many case, the inhibition of both enzymes are higher than or comparable to the standard drug galatamine. With the selectivity index of 2.3 for AChE, compound 5f can be considered as a potential lead compound with a feature of dual AChE/BChE inhibition with IC 50 =1.6±0.10μM (AChE) and 3.7±0.18μM (BChE). Binding modes of the synthesized compounds were explored by using GOLD (Genetic Optimization for Ligand Docking) suit v5.4.1. The computed binding modes of these compounds in the active site of AChE and BChE provide an insight into the mechanism of inhibition of these two enzyme. Copyright © 2017 Elsevier Inc. All rights reserved.

Synthesis, characterization and biocompatibility evaluation of hydroxyapatite - gelatin polyLactic acid ternary nanocomposite

Directory of Open Access Journals (Sweden)

Z. Nabipour

2016-04-01

Full Text Available Objective(s: The current study reports the production and biocompatibility evaluation of a ternary nanocomposite consisting of HA, PLA, and gelatin for biomedical application.Materials and Methods: Hydroxyapatite nanopowder (HA: Ca10(PO46(OH2 was produced by burning the bovine cortical bone within the temperature range of 350-450 oC followed by heating in an oven at 800. Synthesis of the ternary nanocomposite was carried out in two steps: synthesis of gelatin-hydroxyapatite binary nanocomposite and addition of poly lactic acid with different percentages to the resulting composition. The crystal structure was determined by X-ray diffraction (XRD, while major elements and impurities of hydroxyapatite were identified by elemental analysis of X-ray fluorescence (XRF. Functional groups were determined by Fourier transform infrared spectroscopy (FTIR. Morphology and size of the nanocomposites were evaluated using field emission scanning electron microscope (FE-SEM.Biocompatibility of nanocomposites was investigated by MTT assay. Results: XRD patterns verified the ideal crystal structure of the hydroxyapatite, which indicated an appropriate synthesis process and absence of disturbing phases. Results of FTIR analysis determined the polymers’ functional groups, specified formation of the polymers on the hydroxyapatite surface, and verified synthesis of nHA/PLA/Gel composite. FESEM images also indicated the homogeneous structure of the composite in the range of 50 nanometers. MTT assay results confirmed the biocompatibility of nanocomposite samples.Conclusion: This study suggested that the ternary nanocomposite of nHA/PLA/Gel can be a good candidate for biomedical application such as drug delivery systems, but for evaluation of its potential in hard tissue replacement, mechanical tests should be performed.

Nitrocyclopropanes: synthesis and properties

Energy Technology Data Exchange (ETDEWEB)

Averina, Elena B; Yashin, N V; Kuznetsova, Tamara S; Zefirov, Nikolai S [Department of Chemistry, M.V. Lomonosov Moscow State University, Moscow (Russian Federation)

2009-10-31

State-of-the-art data on the methods of synthesis, properties and transformations of nitro- and- dinitrocyclopropanes of different structure is generalized and described systematically. The attention is focused on stereoselective cyclopropanation methods, new approaches to the synthesis of natural products and their synthetic analogues with diversified biological activities, in particular, of aminocyclopropane acids based on nitrocyclopropanes, and the formation of structures of energetic compounds.

Selenium-Doped Hydroxyapatite Nanocrystals–Synthesis, Physicochemical Properties and Biological Significance

Directory of Open Access Journals (Sweden)

Kamil Pajor

2018-04-01

Full Text Available Hydroxyapatites (HAs, as materials with a similar structure to bone minerals, play a key role in biomaterials engineering. They have been applied as bone substitute materials and as coatings for metallic implants, which facilitates their osseointegration. One of the beneficial characteristics of HA, when used to create biocompatible materials with improved physicochemical or biological properties, is its capacity for ionic substitution. The aim of the study was to present the current state of knowledge about HAs containing selenate ions IV or VI. The enrichment of HAs with selenium aims to create a material with advantageous effects on bone tissue metabolism, as well as having anticancer and antibacterial activity. The work is devoted to both methods of obtaining Se-HA and an evaluation of its chemical structure and physicochemical properties. In addition, the biological activity of such materials in vitro and in vivo is discussed.

Synthesis, structural studies and biological properties of new TBA analogues containing an acyclic nucleotide.

Science.gov (United States)

Coppola, Teresa; Varra, Michela; Oliviero, Giorgia; Galeone, Aldo; D'Isa, Giuliana; Mayol, Luciano; Morelli, Elena; Bucci, Maria-Rosaria; Vellecco, Valentina; Cirino, Giuseppe; Borbone, Nicola

2008-09-01

A new modified acyclic nucleoside, namely N(1)-(3-hydroxy-2-hydroxymethyl-2-methylpropyl)-thymidine, was synthesized and transformed into a building block useful for oligonucleotide (ON) automated synthesis. A series of modified thrombin binding aptamers (TBAs) in which the new acyclic nucleoside replaces, one at the time, the thymidine residues were then synthesized and characterized by UV, CD, MS, and (1)H NMR. The biological activity of the resulting TBAs was tested by Prothrombin Time assay (PT assay) and by purified fibrinogen clotting assay. From a structural point of view, nearly all the new TBA analogues show a similar behavior as the unmodified counterpart, being able to fold into a bimolecular or monomolecular quadruplex structure depending on the nature of monovalent cations (sodium or potassium) coordinated in the quadruplex core. From the comparison of structural and biological data, some important structure-activity relationships emerged, particularly when the modification involved the TT loops. In agreement with previous studies we found that the folding ability of TBA analogues is more affected by modifications involving positions 4 and 13, rather than positions 3 and 12. On the other hand, the highest anti-thrombin activities were detected for aptamers containing the modification at T13 or T12 positions, thus indicating that the effects produced by the introduction of the acyclic nucleoside on the biological activity are not tightly connected with structure stabilities. It is noteworthy that the modification at T7 produces an ON being more stable and active than the natural TBA.

Design, synthesis and biological evaluation of novel desmuramyldipeptide analogs.

Science.gov (United States)

Jakopin, Žiga; Corsini, Emanuela; Gobec, Martina; Mlinarič-Raščan, Irena; Dolenc, Marija Sollner

2011-09-01

A series of novel desmuramyldipeptides have been designed and synthesized as part of our search for therapeutically useful muramyldipeptide (MDP) analogs. Their immunomodulatory properties were initially assessed in vitro, evaluating their effect on lipopolysaccharide (LPS)-induced cytokine release in THP-1 cells. Following the initial screening, selected compounds were further investigated for immunomodulatory properties using LPS and phorbol 12-myristate 13-acetate (PMA)/ionomycin-stimulated human peripheral blood mononuclear cells. The results confirmed the immunomodulatory properties of some of the synthesized desmuramyldipeptide analogs. Taken together, presented data confirmed the immunostimulatory effect of compound 44, MDP derivative incorporating a pyrido-fused [1,2]-benzisothiazole moiety, while for compounds 32 and 39, indole scaffold-based derivatives of MDP, an immunosuppressive effect was observed. Further studies will be necessary to address their potential therapeutic use as immunomodulatory drugs, both as immunostimulants or anti-inflammatory agents. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Modified Polyacrylic Acid-Zinc Composites: Synthesis, Characterization and Biological Activity

Directory of Open Access Journals (Sweden)

Mohammed Rafi Shaik

2016-02-01

Full Text Available Polyacrylic acid (PAA is an important industrial chemical, which has been extensively applied in various fields, including for several biomedical purposes. In this study, we report the synthesis and modification of this polymer with various phenol imides, such as succinimide, phthalimide and 1,8-naphthalimide. The as-synthesized derivatives were used to prepare polymer metal composites by the reaction with Zn+2. These composites were characterized by using various techniques, including NMR, FT-IR, TGA, SEM and DSC. The as-prepared PAA-based composites were further evaluated for their anti-microbial properties against various pathogens, which include both Gram-positive and Gram-negative bacteria and different fungal strains. The synthesized composites have displayed considerable biocidal properties, ranging from mild to moderate activities against different strains tested.

Tailored Multivalent Neo-Glycoproteins: Synthesis, Evaluation, and Application of a Library of Galectin-3-Binding Glycan Ligands

Czech Academy of Sciences Publication Activity Database

Laaf, D.; Bojarová, Pavla; Pelantová, Helena; Křen, Vladimír; Elling, L.

2017-01-01

Roč. 28, č. 11 (2017), s. 2832-2840 ISSN 1043-1802 R&D Projects: GA ČR GC15-02578J; GA MŠk(CZ) LTC17005 Institutional support: RVO:61388971 Keywords : HOMOTYPIC CELL-AGGREGATION * ONE-POT SYNTHESIS * GALACTOSE-OXIDASE Subject RIV: CE - Biochemistry OBOR OECD: Biochemistry and molecular biology Impact factor: 4.818, year: 2016

Thiosemicarbazones: preparation methods, synthetic applications and biological importance

International Nuclear Information System (INIS)

Tenorio, Romulo P.; Goes, Alexandre J.S.; Lima, Jose G. de; Faria, Antonio R. de; Alves, Antonio J.; Aquino, Thiago M. de

2005-01-01

Thiosemicarbazones are a class of compounds known by their chemical and biological properties, such as antitumor, antibacterial, antiviral and antiprotozoal activity. Their ability to form chelates with metals has great importance in their biological activities. Their synthesis is very simple, versatile and clean, usually giving high yields. They are largely employed as intermediates, in the synthesis of others compounds. This article is a survey of some of these characteristics showing their great importance to organic and medicinal chemistry. (author)

A synthesis of evaluation monitoring projects by the forest health monitoring program (1998-2007)

Science.gov (United States)

William A. Bechtold; Michael J. Bohne; Barbara L. Conkling; Dana L. Friedman

2012-01-01

The national Forest Health Monitoring Program of the Forest Service, U.S. Department of Agriculture, has funded over 200 Evaluation Monitoring projects. Evaluation Monitoring is designed to verify and define the extent of deterioration in forest ecosystems where potential problems have been identified. This report is a synthesis of results from over 150 Evaluation...

Synthesis, Characterization and Biological Evaluation of Transition Metal Complexes Derived from N, S Bidentate Ligands

Directory of Open Access Journals (Sweden)

Enis Nadia Md Yusof

2015-05-01

Full Text Available Two bidentate NS ligands were synthesized by the condensation reaction of S-2-methylbenzyldithiocarbazate (S2MBDTC with 2-methoxybenzaldehyde (2MB and 3-methoxybenzaldehyde (3MB. The ligands were reacted separately with acetates of Cu(II, Ni(II and Zn(II yielding 1:2 (metal:ligand complexes. The metal complexes formed were expected to have a general formula of [M(NS2] where M = Cu2+, Ni2+, and Zn2+. These compounds were characterized by elemental analysis, molar conductivity, magnetic susceptibility and various spectroscopic techniques. The magnetic susceptibility measurements and spectral results supported the predicted coordination geometry in which the Schiff bases behaved as bidentate NS donor ligands coordinating via the azomethine nitrogen and thiolate sulfur. The molecular structures of the isomeric S2M2MBH (1 and S2M3MBH (2 were established by X-ray crystallography to have very similar l-shaped structures. The Schiff bases and their metal complexes were evaluated for their biological activities against estrogen receptor-positive (MCF-7 and estrogen receptor-negative (MDA-MB-231 breast cancer cell lines. Only the Cu(II complexes showed marked cytotoxicity against the cancer cell lines. Both Schiff bases and other metal complexes were found to be inactive. In concordance with the cytotoxicity studies, the DNA binding studies indicated that Cu(II complexes have a strong DNA binding affinity.

Synthesis, characterization and biological studies of copper oxide nanostructures

Science.gov (United States)

Jillani, Saquf; Jelani, Mohsan; Hassan, Najam Ul; Ahmad, Shahbaz; Hafeez, Muhammad

2018-04-01

The development of synthetic methods has been broadly accepted as an area of fundamental importance to the understanding and application of nanoscale materials. It allows the individual to modulate basic parameters such as morphology, particle size, size distributions, and composition. Several methods have been developed to synthesize CuO nanostructures with diverse morphologies, sizes, and dimensions using different chemical and physical based approaches. In this work, CuO nanostructures have been synthesized by aqueous precipitation method and simple chemical deposition method. The characterization of these products has been carried out by the x-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Fourier Transform Infrared (FTIR) and UV–vis spectroscopy. Biological activity such as antibacterial nature of synthesized CuO is also explored. XRD peaks analysis revealed the monoclinic crystalline phase of copper oxide nanostructures. While the rod-like and particle-like morphologies have been observed in SEM results. FTIR spectra have confirmed the formation of CuO nanoparticles by exhibiting its characteristic peaks corresponding to 494 cm‑1 and 604 cm‑1. The energy band gap of the as-prepared CuO nanostructures determined from UV–vis spectra is found to be 2.18 eV and 2.0 eV for precipitation and chemically deposited samples respectively. The antibacterial activity results described that the synthesized CuO nanoparticles showed better activity against Staphylococcus aureus. The investigated results suggested the synthesis of highly stable CuO nanoparticles with significant antibacterial activities.

Droplet-based microfluidic method for synthesis of microparticles

CSIR Research Space (South Africa)

Mbanjwa, MB

2012-10-01

Full Text Available Droplet-based microfluidics has, in recent years, received increased attention as an important tool for performing numerous methods in modern day chemistry and biology such as the synthesis of hydrogel microparticles. Hydrogels have been used in many..., in recent years, received increased attention as an important tool for performing numerous methods in modern day chemistry and biology, such as synthesis of hydrogel microparticles. CONCLUSION AND OUTLOOK The droplet-based microfluidic method offers...

Synthetic Biology with Cytochromes P450 Using Photosynthetic Chassis

DEFF Research Database (Denmark)

Gnanasekaran, Thiyagarajan

, this modern field of synthetic biology is completely dependent on the nature of the chassis - the host organisms - for its endeavor. Of all the chassis, photosynthetic organisms such as cyanobacteria and plants gains special attention due to the remarkable amount of sunlight that is striking the Earth...... in cyanobacteria and plant chloroplasts for the purpose of light driven synthesis of bioactive compounds by using synthetic biology approaches. As model pathways, in this thesis, the pathway involved in the synthesis of the cyanogenic glucoside dhurrin from Sorghum bicolor, and the pathway involved......Synthetic biology is a rapidly growing engineering discipline in biology. It aims at building novel biological systems that do not exist in nature by selecting the interchangeable standardized biological parts that are already available in the nature, and assembling them in a specific order. Today...

Simultaneous removal and evaluation of organic substrates and NH{sub 3}-N by a novel combined process in treating chemical synthesis-based pharmaceutical wastewater

Energy Technology Data Exchange (ETDEWEB)

Chen, Zhaobo [School of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China); State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Wang, Hongcheng [School of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China); Ren, Nanqi, E-mail: rnq@hit.edu.cn [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Cui, Minhua; Nie, Shukai; Hu, Dongxue [School of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China)

2011-12-15

Highlights: Black-Right-Pointing-Pointer We research a novel combined process to treat chemical synthesis-based pharmaceutical wastewater. Black-Right-Pointing-Pointer The mechanism of amoxicillin verifies that the biodegradation, adsorption, hydrolysis and unknown mechanism were able to remove amoxicillin from wastewater. Black-Right-Pointing-Pointer In this study demonstrates that biodegradation is the major factor for removal mechanism at work for amoxicillin. Black-Right-Pointing-Pointer Mathematical statistic methods were employed to evaluate the performance of the WWTP. - Abstract: A full-scale novel combined anaerobic/micro-aerobic and two-stage aerobic biological process is used for the treatment of an actual chemical synthesis-based pharmaceutical wastewater containing amoxicillin. The anaerobic system is an up-flow anaerobic sludge blanket (UASB), the micro-aerobic system is a novel micro-aerobic hydrolysis acidification reactor (NHAR) and the two-stage aerobic process comprised cyclic activated sludge system (CASS) and biological contact oxidation tank (BCOT). The influent wastewater was high in COD, NH{sub 3}-N varying daily 4016-13,093 mg-COD L{sup -1} and 156.4-650.2 mg-NH{sub 3}-N L{sup -1}, amoxicillin varying weekly between 69.1 and 105.4 mg-amoxicillin L{sup -1}, respectively; Almost all the COD, NH{sub 3}-N, amoxicillin were removed by the biological combined system, with removal percentages 97%, 93.4% and 97.2%, respectively, leaving around 104 mg-COD L{sup -1}, 9.4 mg-NH{sub 3}-N L{sup -1} and 2.6 {+-} 0.8 mg-amoxicillin L{sup -1} in the final clarifier effluent. The performance evaluation of the wastewater treatment plant (WWTP) by mathematical statistic methods shown that at most of time effluent can meet the higher treatment discharge standard. In addition, the fate of amoxicillin in the full-scale WWTP and the amoxicillin removal rate of each different removal routes in UASB, NHAR, CASS, BCOT and final clarifier processes are investigated

Novel thrombopoietin mimetic peptides bind c-Mpl receptor: Synthesis, biological evaluation and molecular modeling.

Science.gov (United States)

Liu, Yaquan; Tian, Fang; Zhi, Dejuan; Wang, Haiqing; Zhao, Chunyan; Li, Hongyu

2017-02-01

Thrombopoietin (TPO) acts in promoting the proliferation of hematopoietic stem cells and by initiating specific maturation events in megakaryocytes. Now, TPO-mimetic peptides with amino acid sequences unrelated to TPO are of considerable pharmaceutical interest. In the present paper, four new TPO mimetic peptides that bind and activate c-Mpl receptor have been identified, synthesized and tested by Dual-Luciferase reporter gene assay for biological activities. The molecular modeling research was also approached to understand key molecular mechanisms and structural features responsible for peptide binding with c-Mpl receptor. The results presented that three of four mimetic peptides showed significant activities. In addition, the molecular modeling approaches proved hydrophobic interactions were the driven positive forces for binding behavior between peptides and c-Mpl receptor. TPO peptide residues in P7, P13 and P7' positions were identified by the analysis of hydrogen bonds and energy decompositions as the key ones for benefiting better biological activities. Our data suggested the synthesized peptides have considerable potential for the future development of stable and highly active TPO mimetic peptides. Copyright © 2016 Elsevier Ltd. All rights reserved.

Matrix-assisted peptide synthesis on nanoparticles.

Science.gov (United States)

Khandadash, Raz; Machtey, Victoria; Weiss, Aryeh; Byk, Gerardo

2014-09-01

We report a new method for multistep peptide synthesis on polymeric nanoparticles of differing sizes. Polymeric nanoparticles were functionalized via their temporary embedment into a magnetic inorganic matrix that allows multistep peptide synthesis. The matrix is removed at the end of the process for obtaining nanoparticles functionalized with peptides. The matrix-assisted synthesis on nanoparticles was proved by generating various biologically relevant peptides. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.

SYNTHESIS, CHARACTERIZATION AND BIO-ACTIVITY OF SOME ...

African Journals Online (AJOL)

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Organophosphorus compounds have wide range of applications in the industrial, agricultural and medicinal chemistry owing to their unique physicochemical and biological properties. Their utility as reagents and potential synthons in organic synthesis is gaining increased attention [1]. Synthesis of a-aminophosphonates, ...

SYNTHESIS AND BIOLOGIC PROPERTIES OF SOME 1-(ALCHYLPHENYL-3-(4-(3-(PYRIDIN-2-ILACRYLOYLPHENYLTHIOUREA

Directory of Open Access Journals (Sweden)

A. Popusoi

2013-06-01

Full Text Available This paper describe the synthesis of some 1-(alchylaril-3-(4-(3-pyridin-2-il acryloylphenylthiourea obtained by condensation of 2-pyridincarboxaldehide with some derivatives of 4-acetylphenilthioureas in basic medium or by addition of aliphatic and aromatic amines to the correspondingisothiocyanatopropenones. 12 new compounds were obtained and their biological properties were analysed. The substituted thioureas by pyridine radicals, morpholine and phenol show a maximum bacteriostatic activity for Gram positive microorganisms like: Staphylococcus Aureus and Enterococcus Faecalis at the minimum inhibitory concentration 9.37-37.5 μM. Antifungal activity for Candida Albicans, Aspergillus Niger, AspergillusFumigatus, Penicillium is weak, in minimum inhibitory concentration 600->600 μM. The leukemia activity like inhibitor (HL-60, is 84-96.9% at the concentration 10-5mol/l and 15- 20% and at the concentrations 10-6, 10-7mol/l.

Gold nanoparticles synthesis and biological activity estimation in vitro and in vivo.

Science.gov (United States)

Rieznichenko, L S; Dybkova, S M; Gruzina, T G; Ulberg, Z R; Todor, I N; Lukyanova, N Yu; Shpyleva, S I; Chekhun, V F

2012-01-01

The aim of the work was the synthesis of gold nanoparticles (GNP) of different sizes and the estimation of their biological activity in vitro and in vivo. Water dispersions of gold nanoparticles of different sizes have been synthesized by Davis method and characterized by laser-correlation spectroscopy and transmission electron microscopy methods. The GNP interaction with tumor cells has been visualized by confocal microscopy method. The enzyme activity was determined by standard biochemical methods. GNP distribution and content in organs and tissues have been determined via atomic-absorption spectrometry method; genotoxic influence has been estimated by "Comet-assay" method. The GNP size-dependent accumulation in cultured U937 tumor cells and their ability to modulate U937 cell membrane Na(+),K(+)-АТР-ase activity value has been revealed in vitro. Using in vivo model of Guerin carcinoma it has been shown that GNP possess high affinity to tumor cells. Our results indicate the perspectives of use of the synthesized GNP water dispersions for cancer diagnostics and treatment. It's necessary to take into account a size-dependent biosafety level of nanoparticles.

Replacement of the double bond of antitubulin chalcones with triazoles and tetrazoles: Synthesis and biological evaluation.

Science.gov (United States)

Mesenzani, Ornella; Massarotti, Alberto; Giustiniano, Mariateresa; Pirali, Tracey; Bevilacqua, Valentina; Caldarelli, Antonio; Canonico, Pierluigi; Sorba, Giovanni; Novellino, Ettore; Genazzani, Armando A; Tron, Gian Cesare

2011-01-15

In the chalcone scaffold, it is thought that the double bond is an important structural linker but it is likely not essential for the interaction with tubulin. Yet, it may be a potential site of metabolic degradation and interaction with biological nucleophiles. In this letter, we have replaced this olefinic portion of chalcones with two metabolically stable and chemically inert heterocyclic rings, namely triazole or tetrazole. Yet, our biologic data suggest that, unlike in other antitubulinic structures, the olephinic ring might not be merely a structural linker. Copyright © 2010 Elsevier Ltd. All rights reserved.

Synthesis of biological active thiosemicarbazone and characterization of the interaction with human serum albumin

Energy Technology Data Exchange (ETDEWEB)

Yu, Wangshu; Shi, Lei; Hui, Guangquan [College of Chemistry and Environmental Science, Henan Normal University, Xinxiang 453007 (China); Cui, Fengling, E-mail: fenglingcui@hotmail.com [College of Chemistry and Environmental Science, Henan Normal University, Xinxiang 453007 (China)

2013-02-15

The synthesis of a new biological active reagent, 2-((1,4-dihydroxy)-9,10-anthraquinone) aldehyde thiosemicarbazone (DHAQTS), was designed. The interaction between DHAQTS and HSA was studied by fluorescence spectroscopy in combination with molecular modeling under simulation of physiological conditions. According to the results of fluorescence measurements, the quenching mechanism was suggested to be static. The thermodynamic parameters are calculated by van't Hoff equation, which demonstrated that hydrophobic interactions are the predominant intermolecular forces stabilizing the complex. The number of binding sites (n) was calculated. Through the site marker competitive experiment, DHAQTS was confirmed to be located in site I of HSA. The binding distance r=2.83 nm between the donor HSA and acceptor DHAQTS was obtained according to Foerster's non-radiative energy transfer theory. The three-dimensional fluorescence spectral results showed the conformation and microenvironment of HSA changed in the presence of DHAQTS. The effects of common ions on the binding of DHAQTS to HSA were also evaluated. The experimental results were in agreement with the results obtained via a molecular docking study. - Highlights: Black-Right-Pointing-Pointer 2-((1,4-dihydroxy)-9,10-anthraquinone)aldehyde thiosemicarbazone (DHAQTS) was synthesized. Black-Right-Pointing-Pointer DHAQTS can quench the fluorescence of human serum albumin (HSA) by static quenching mechanism. Black-Right-Pointing-Pointer Hydrophobic interactions were the predominant intermolecular forces. Black-Right-Pointing-Pointer The competitive experiment was carried out to identify the DHAQTS binding site on HSA. Black-Right-Pointing-Pointer Three-dimensional spectra confirmed DHAQTS caused the conformational change of HSA.

Biological activities of xanthatin from Xanthium strumarium leaves.

Science.gov (United States)

Nibret, Endalkachew; Youns, Mahamoud; Krauth-Siegel, R Luise; Wink, Michael

2011-12-01

The objective of the present work was to evaluate the biological activities of the major bioactive compound, xanthatin, and other compounds from Xanthium strumarium (Asteraceae) leaves. Inhibition of bloodstream forms of Trypanosoma brucei brucei and leukaemia HL-60 cell proliferation was assessed using resazurin as a vital stain. Xanthatin was found to be the major and most active compound against T. b. brucei with an IC(50) value of 2.63 µg/mL and a selectivity index of 20. The possible mode of action of xanthatin was further evaluated. Xanthatin showed antiinflammatory activity by inhibiting both PGE(2) synthesis (24% inhibition) and 5-lipoxygenase activity (92% inhibition) at concentrations of 100 µg/mL and 97 µg/mL, respectively. Xanthatin exhibited weak irreversible inhibition of parasite specific trypanothione reductase. Unlike xanthatin, diminazene aceturate and ethidium bromide showed strong DNA intercalation with IC(50) values of 26.04 µg/mL and 44.70 µg/mL, respectively. Substantial induction of caspase 3/7 activity in MIA PaCa-2 cells was observed after 6 h of treatment with 100 µg/mL of xanthatin. All these data taken together suggest that xanthatin exerts its biological activity by inducing apoptosis and inhibiting both PGE(2) synthesis and 5-lipoxygenase activity thereby avoiding unwanted inflammation commonly observed in diseases such as trypanosomiasis. Copyright © 2011 John Wiley & Sons, Ltd.

Synthesis and biological evaluation of isomeric methoxy substitutions on anti-cancer indolyl-pyridinyl-propenones: Effects on potency and mode of activity.

Science.gov (United States)

Trabbic, Christopher J; George, Sage M; Alexander, Evan M; Du, Shengnan; Offenbacher, Jennifer M; Crissman, Emily J; Overmeyer, Jean H; Maltese, William A; Erhardt, Paul W

2016-10-21

Certain indolyl-pyridinyl-propenone analogues kill glioblastoma cells that have become resistant to conventional therapeutic drugs. Some of these analogues induce a novel form of non-apoptotic cell death called methuosis, while others primarily cause microtubule disruption. Ready access to 5-indole substitution has allowed characterization of this position to be important for both types of mechanisms when a simple methoxy group is present. We now report the syntheses and biological effects of isomeric methoxy substitutions on the indole ring. Additionally, analogues containing a trimethoxyphenyl group in place of the pyridinyl moiety were evaluated for anticancer activity. The results demonstrate that the location of the methoxy group can alter both the potency and the mechanism of cell death. Remarkably, changing the methoxy from the 5-position to the 6-position switched the biological activity from induction of methuosis to disruption of microtubules. The latter may represent a prototype for a new class of mitotic inhibitors with potential therapeutic utility. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Synthesis, crystal structure and biological activity of novel diester cyclophanes

International Nuclear Information System (INIS)

Zhang, Pengfei; Yang, Bingqin; Fang, Xianwen; Cheng, Zhao; Yang, Meipan

2012-01-01

A series of novel diester cyclophanes was synthesized by esterification of 1,2-benzenedicarbonyl chloride with eight different diols under high dilution conditions. The structures of the compounds were verified by elemental analysis, 1 H nuclear magnetic resonance (NMR), IR spectroscopy and high resolution mass spectrometry (HRMS). The crystal structures of two compounds were characterized by single crystal X-ray diffractometry (XRD). All the new cyclophanes were evaluated for biological activities and the results showed that some of these compounds have low antibacterial or antifungal activities (author)

Uncertainty analysis: an evaluation metric for synthesis science

Science.gov (United States)

Mark E. Harmon; Becky Fasth; Charles B. Halpern; James A. Lutz

2015-01-01

The methods for conducting reductionist ecological science are well known and widely used. In contrast, those used in the synthesis of ecological science (i.e., synthesis science) are still being developed, vary widely, and often lack the rigor of reductionist approaches. This is unfortunate because the synthesis of ecological parts into a greater whole is...

Synthesis of tritium labelled phosphonate analogues of sphinganine-1-phosphate

International Nuclear Information System (INIS)

Schick, Andreas; Schwarzmann, Guenter; Kolter, Thomas; Sandhoff, Konrad

1997-01-01

Tritiated phosphonate analogues 9 and 10 are prepared as analogues of sphinganine-1-phosphate 4. The key step in this synthesis is the catalytic tritiation of the triple bond in reduction of the protected diethyl-3-(S)-tert.-butoxycarbonylamino -4-hydroxy-5-tridecinyl-1-phosphonate by means of sodium boro[ 3 H]hydride as tritium source. These compounds are synthesized to study their metabolic stability and to evaluate their biological properties. (author)

Seco-B-Ring Steroidal Dienynes with Aromatic D Ring: Design, Synthesis and Biological Evaluation

Directory of Open Access Journals (Sweden)

Marcin Szybinski

2017-10-01

Full Text Available Continuing our structure-activity studies on the vitamin D analogs with the altered intercyclic seco-B-ring fragment, we designed compounds possessing dienyne system conjugated with the benzene D ring. Analysis of the literature data and the docking experiments seemed to indicate that the target compounds could mimic the ligands with a good affinity to the vitamin D receptor (VDR. Multi-step synthesis of the C/D-ring building block of the tetralone structure was achieved and its enol triflate was coupled with the known A-ring fragments, possessing conjugated enyne moiety, using Sonogashira protocol. The structures of the final products were confirmed by NMR, UV and mass spectroscopy. Their binding affinities for the full-length human VDR were determined and it was established that compound substituted at C-2 with exomethylene group showed significant binding to the receptor. This analog was also able to induce monocytic differentiation of HL-60 cells.

Design and evaluation of a gesture driven wavefield synthesis auditory game

DEFF Research Database (Denmark)

Grani, Francesco; Paisa, Razvan; Banas, Jan Stian

2016-01-01

An auditory game has been developed as a part of research in Wavefield Synthesis. In order to design and implement this game, a number of technologies have been incorporated in the development process. By pairing motion capture with a WiiMote new dimension of movement input was achieved. We present...... an evaluation study where the game was assessed....

Synthesis and biological evaluation of cyclic analogs of L-carnitine as potential agents in the treatment of myocardial ischemia

International Nuclear Information System (INIS)

Woster, P.M.

1987-01-01

The purpose of this research was to synthesize a number of cyclic, rigid analogs of L-carnitine, having a variety of predetermined positional and stereochemical orientations, to be used as probes into the spatial and conformational requirements of the enzyme known as carnitine/acylcarnitine translocase. The ability of these analogs to serve as substrates for this enzyme was to be determined by assessing the degree to which they initiate efflux of 14 C-L-carnitine from isolated heart mitochondria. Toward this end, synthesis of several such analogs was attempted, resulting in the isolation and characterization of 9 cyclic analogs of carnitine, 5 of which are previously unreported. Bioevaluation of these synthetic carnitine analogs was conducted in a previously described assay system. Rat heart mitochondria were isolated by differential centrifugation and prepared for the study by incubation with 14 C-L-carnitine. Efflux of radiolabeled carnitine was then monitored in the presence of the compound being evaluated. This represents the first instance in which non-naturally occurring analogs of L-carnitine have been shown to undergo transport via this mitochondrial translocase, suggesting the possibility that cyclic carnitine analogs may find utility as agents in the treatment of myocardial ischemia

Synthetic biology and regulatory networks: where metabolic systems biology meets control engineering

NARCIS (Netherlands)

He, F.; Murabito, E.; Westerhoff, H.V.

2016-01-01

Metabolic pathways can be engineered to maximize the synthesis of various products of interest. With the advent of computational systems biology, this endeavour is usually carried out throughin silicotheoretical studies with the aim to guide and complement furtherin vitroandin vivoexperimental

Novel 2,3-Dihydro-1H-pyrrolo[3,2,1-ij]quinazolin-1-ones: Synthesis and Biological Evaluation

Directory of Open Access Journals (Sweden)

Malose J. Mphahlele

2016-12-01

Full Text Available Herein we describe the synthesis and evaluation of a series of novel 2,3-dihydro-1H-pyrrolo[3,2,1-ij]quinazolin-1-ones for in vitro cytotoxicity against three human cancer cell lines as well as for potential antimalarial activity against the chloroquine-sensitive strain 3D7 of Plasmodium falciparum. The title compounds were prepared via PdCl2-mediated endo-dig cyclization of 2-aryl-8-(arylethynyl-6-bromo-2,3-dihydroquinazolin-4(1H-ones. The latter were prepared, in turn, via initial Sonogashira cross-coupling of 2-amino-5-bromo-3-iodobenzamide with aryl acetylenes followed by boric acid-mediated cyclocondensation of the intermediate 2-amino-3-(arylethynyl-5-bromobenzamides with benzaldehyde derivatives. The 2,3-dihydro-1H-pyrrolo[3,2,1-ij]quinazolin-1-ones 4a–k were evaluated for potential in vitro cytotoxicity against the breast (MCF-7, melanoma (B16 and endothelioma (sEnd.2 cell lines. All of the compounds except 4h and 4i were found to be inactive against the three cancer cell lines. Compound 4h substituted with a 4-methoxyphenyl and 4-fluorophenyl groups at the 3- and 5-positions was found to exhibit significant cytotoxicity against the three cancer cell lines. The presence of phenyl and 3-chlorophenyl groups at the 3- and 5-posiitons of the pyrroloquinazolinone 4i, on the other hand, resulted in significant cytotoxicity against vascular tumour endothelial cells (sEnd.2, but reduced activity against the melanoma (B16 and breast cancer (MCF-7 cells except at higher concentrations. The 2,3-dihydro-1H-pyrrolo[3,2,1-ij]quinazolin-1-ones 4a–l were found to be inactive against the chloroquine sensitive 3D7 strain of Plasmodium falciparum.

Enzymatic synthesis of {sup 125/131}I labeled 8-hydroxyquinoline glucuronide and in vitro/in vivo evaluation of biological influence

Energy Technology Data Exchange (ETDEWEB)

Yesilagac, Reyhan [Ege University, Institute of Nuclear Science, 35100 Bornova, Izmir (Turkey); Unak, Perihan, E-mail: perihan.unak@ege.edu.t [Ege University, Institute of Nuclear Science, 35100 Bornova, Izmir (Turkey); Medine, E. Ilker; Ichedef, Cigdem A. [Ege University, Institute of Nuclear Science, 35100 Bornova, Izmir (Turkey); Ertay, Turkan [Dokuz Eyluel University, Medical School, Department of Nuclear Medicine, Inciralti, Izmir (Turkey); Mueftueler, F.Z. Biber [Ege University, Institute of Nuclear Science, 35100 Bornova, Izmir (Turkey)

2011-02-15

8-Hydroxyquinoline (8-OHQ) is a long-known molecule which due to its metal-complexation ability is frequently used for analysis. It is also called oxine. Oxine and derivatives have been investigated to process antitumor and antimicrobial activities. 8-Hydroxyquinolyl-glucuronide (8-OHQ-Glu) was enzymatically synthesized using microsome preparates separated from Hutu-80 cells, labeled with {sup 125}I to perform a radionuclide labeled prodrug and investigated of its biological affinities on Hutu-80 (human duodenum intestinal adenocarcinoma), Caco-2 (human colorectal adenocarcinoma), Detroit 562 (human pharynx adenocarcinoma) cells and ACBRI 519 (primary human small intestine epithelial cells) in this work. UDP-glucuronyl transferase (UDPGT) rich microsome preparates, which are used for glucuronidation in enzymatic synthesis, were extracted from Hutu-80 cells. 8-OHQ-Glu components were labeled using iodogen method with {sup 125}I and {sup 131}I. Structural analyses were performed with LC/MS/MS, {sup 1}H NMR and {sup 13}C-MMR for identify and measure chemical constituents. Results confirmed expected molecular structure. 8-OHQ-Glu could successfully radioiodinated with {sup 125/131}I according to iodogen method. {sup 125}I-8-OHQ-glucuronide incorporated with human gastrointestinal cancer cells such as Detroit-562 (human pharynx adenocarcinoma) (12.6%), Caco-2 (human colorectal adenocarcinoma) (7.8%), Hutu- 80 (human duodenum intestinal adenocarcinoma) (9.5%) and ACBRI 519 (primary human small intestine epithelial cells) (6.40%). {sup 131}I-8-OHQ-Glu was tested in mice bearing subcutaneously implanted Caco-2 colorectal adenocarcinoma cells. The results demonstrated that radioiodinated 8-OHQ-Glu may be promising anticancer prodrug.

[{sup 18}F]norchlorofluorohomoepibatidine. Synthesis, radiosynthesis, evaluation in vitro and comparison with 2-[{sup 18}F]fluoro-A-85380 in mice

Energy Technology Data Exchange (ETDEWEB)

Patt, J.T.; Deuther-Conrad, W.; Brust, P.; Steinbach, J. [Institut fuer Interdisziplinaere Isotopenforschung, Leipzig (Germany); Patt, M.; Schildan, A.; Sabri, O. [Klinik und Poliklinik fuer Nuklearmedizin, Leipzig (Germany); Feuerbach, D. [Novartis Pharma AG, Basel (Switzerland)

2004-07-01

In this abstract we describe synthesis, radiosynthesis and biological evalution of both stereoisomers of NCFHEB (norchlorofluorohomoepibatidine) and compare the biodistribution data with 2-[{sup 18}F]fluoro-A-85380, a tracer currently used for imaging nicotinic receptors with PET. (orig.)

Synthesis and biological properties of novel 2-aminopyrimidin-4(3H)-ones highly potent against HIV-1 mutant strains.

Science.gov (United States)

Mai, Antonello; Artico, Marino; Rotili, Dante; Tarantino, Domenico; Clotet-Codina, Imma; Armand-Ugón, Mercedes; Ragno, Rino; Simeoni, Silvia; Sbardella, Gianluca; Nawrozkij, Maxim B; Samuele, Alberta; Maga, Giovanni; Esté, José A

2007-11-01

Following the disclosure of dihydro-alkoxy-, dihydro-alkylthio-, and dihydro-alkylamino-benzyl-oxopyrimidines (DABOs, S-DABOs, and NH-DABOs) as potent and selective anti-HIV-1 agents belonging to the non-nucleoside reverse transcriptase inhibitor (NNRTI) class, we report here the synthesis and biological evaluation of a novel series of DABOs bearing a N,N-disubstituted amino group or a cyclic amine at the pyrimidine-C2 position, a hydrogen atom or a small alkyl group at C5 and/or at the benzylic position, and the favorable 2,6-difluorobenzyl moiety at the C6 position (F2-N,N-DABOs). The new compounds were highly active up to the subnanomolar level against both wt HIV-1 and the Y181C mutant and at the submicromolar to nanomolar range against the K103N and Y188L mutant strains. Such derivatives were more potent than S-DABOs, NH-DABOs, and nevirapine and efavirenz were chosen as reference drugs. The higher inhibitor adaptability to the HIV-1 RT non-nucleoside binding site (NNBS) may account for the higher inhibitory effect exerted by the new molecules against the mutated RTs.

Design synthesis and biological evaluation of 2-methylphenyl semicarbazone derivatives

Directory of Open Access Journals (Sweden)

Manmohan Singhal

2011-03-01

Full Text Available We have used pharmacophore hybridization technique of drug design and designed a pharmacophore model 2-methylphenylsemicarbazone which is having hydrogen acceptor site, hydrogen donor site, lipophilic site etc using ligandscout-2.02 software. A series of 2-methylphenyl-semicarbazone was synthesized and evaluated for their antipyretic activity using boiled cow milk induced pyrexia in rabbits. Compound 11 was the most active compound. The possible metabolites of some selected synthesized chalconesemicarbazones were predicted by computational method using Pallas version-3.1 ADME-Tox prediction software. The major pathway of metabolism was found to be p-hydroxylation and amide hydrolysis.

Synthesis and characterization of polyglycerols dendrimers for applications in tissue engineering biological

International Nuclear Information System (INIS)

Passos, E.D.; Queiroz, A.A.A. de

2014-01-01

Full text: Introduction: Over the last twenty years is the growing development in the manufacture of synthetic scaffold in tissue engineering applications. These new materials are based on polyglycerol dendrimers (PGLD's). PGLD's are highly functional polymers with hydroxymethyl side groups, fulfill all structural prerequisites to replace poly(ethylene glycol)s in medical applications. Furthermore, since these materials are based on naturally occurring compounds that degrades over time in the body and can be safely excreted. The objective of this work was the synthesis, physicochemical, biological characterization of HPGL's with potential use as scaffolds in tissue engineering. HPGL's with oligomeric cores, of diglycerol triglycerol and tetraglycerol was used. Theoretical and Experimental Simulation Details: The synthesis of PGLD procedures involves the etherification of glycerol through anionic polymerization of glycidol. The PGLD's were characterized by chromatographic techniques (SEC and HPLC), spectroscopic (FTIR, 1H-NMR and 13C - NMR) electrochemical (zeta potential) and thermal analysis (DSC and TGA) techniques. The structure- activity relationships (SAR's) of compound prototype and its analogs were studied to determine the generation number (G) of the molecule responsible for the biological activity on the adhesion and cell proliferation process. A detailed study of the structure of PGLD's of G=0-4 was performed using the Hyperchem 7. 5 and Gromacs 4 software packages. The biocompatibility studies were studied by scanning electron microscopy (SEM) and fluorescence microscopy (EPF) technique after PGLD (G=0-4) blood contact. The overall electro-negativity/total charge density, dipole moment, frontier orbital's (HOMO - LUMO) and electrostatic potential maps (EPM) were calculated. The most stable form of the resulting compounds was determined by estimating the hydration energy and energy conformation. Results and Discussion: The techniques SEM and EPF

Rewiring protein synthesis: From natural to synthetic amino acids.

Science.gov (United States)

Fan, Yongqiang; Evans, Christopher R; Ling, Jiqiang

2017-11-01

The protein synthesis machinery uses 22 natural amino acids as building blocks that faithfully decode the genetic information. Such fidelity is controlled at multiple steps and can be compromised in nature and in the laboratory to rewire protein synthesis with natural and synthetic amino acids. This review summarizes the major quality control mechanisms during protein synthesis, including aminoacyl-tRNA synthetases, elongation factors, and the ribosome. We will discuss evolution and engineering of such components that allow incorporation of natural and synthetic amino acids at positions that deviate from the standard genetic code. The protein synthesis machinery is highly selective, yet not fixed, for the correct amino acids that match the mRNA codons. Ambiguous translation of a codon with multiple amino acids or complete reassignment of a codon with a synthetic amino acid diversifies the proteome. Expanding the genetic code with synthetic amino acids through rewiring protein synthesis has broad applications in synthetic biology and chemical biology. Biochemical, structural, and genetic studies of the translational quality control mechanisms are not only crucial to understand the physiological role of translational fidelity and evolution of the genetic code, but also enable us to better design biological parts to expand the proteomes of synthetic organisms. This article is part of a Special Issue entitled "Biochemistry of Synthetic Biology - Recent Developments" Guest Editor: Dr. Ilka Heinemann and Dr. Patrick O'Donoghue. Copyright © 2017 Elsevier B.V. All rights reserved.

Synthesis, physical-chemical and biological properties of 7-benzyl-3-methyl-8-thioxanthine derivatives

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D. H. Ivanchenko

2017-12-01

Full Text Available Introduction . Interest to the problem of creating new effective antimicrobial agents among xanthine derivatives does not decrease. Primarily, this is due to the increasing of microbial resistance to conventional antimicrobial agents and the emergence of their new strains. In recent years interest to the therapeutic use of antioxidants in the treatment of diseases associated with oxidative stress has increased. The aim of this work is to elaborate simple laboratory methods of 7-benzyl-3-methyl-8-thioxanthine derivatives synthesis, unspecified in scientific papers earlier, and to study their physical, chemical and biological properties. Materials and methods. The melting point has been determined with the help of an open capillary method with PTP-M device. Elemental analysis has been performed with the help of the instrument Elementar Vario L cube, NMR-spectra have been taken on a spectrometer Bruker SF-400 (operating frequency of 400 MHz, solvent DMSO, internal standard – TMS. Study of antimicrobial and antifungal activity of synthesized compounds has been performed by two-fold serial dilution method. Standard test strains have been used for the study: Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Candida albicans ATCC 885-653. Dimethylsulfoxide was used as the solvent of the compounds. Results. Under short-time heating up of the initial 7-benzyl-3-methyl-8-thioxanthine with alkyl, alkenyl, benzyl halides or heteroalkylchlorides in a water-propanol-2 mixture in the presence of an equimolar amount of sodium hydroxide leads to the formation of 8-S-substituted of 7-benzyl-3-methylxanthines. Structure of synthesized compounds was definitely proved by NMR-spectroscopy. We conducted primary screening research of antimicrobial activity of 7-benzyl-3-methyl-8-thioxanthine derivatives, which revealed moderate and weak activity in concentrations 50-100 mcg/ml. Most of the obtained compounds showed a

Five Decades with Polyunsaturated Fatty Acids: Chemical Synthesis, Enzymatic Formation, Lipid Peroxidation and Its Biological Effects

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Angel Catalá

2013-01-01

Full Text Available I have been involved in research on polyunsaturated fatty acids since 1964 and this review is intended to cover some of the most important aspects of this work. Polyunsaturated fatty acids have followed me during my whole scientific career and I have published a number of studies concerned with different aspects of them such as chemical synthesis, enzymatic formation, metabolism, transport, physical, chemical, and catalytic properties of a reconstructed desaturase system in liposomes, lipid peroxidation, and their effects. The first project I became involved in was the organic synthesis of [1-14C] eicosa-11,14-dienoic acid, with the aim of demonstrating the participation of that compound as a possible intermediary in the biosynthesis of arachidonic acid “in vivo.” From 1966 to 1982, I was involved in several projects that study the metabolism of polyunsaturated fatty acids. In the eighties, we studied fatty acid binding protein. From 1990 up to now, our laboratory has been interested in the lipid peroxidation of biological membranes from various tissues and different species as well as liposomes prepared with phospholipids rich in PUFAs. We tested the effect of many antioxidants such as alpha tocopherol, vitamin A, melatonin and its structural analogues, and conjugated linoleic acid, among others.

Synthesis of Polycyclic Natural Products

Energy Technology Data Exchange (ETDEWEB)

Nguyen, Tuan Hoang [Iowa State Univ., Ames, IA (United States)

2003-01-01

With the continuous advancements in molecular biology and modern medicine, organic synthesis has become vital to the support and extension of those discoveries. The isolations of new natural products allow for the understanding of their biological activities and therapeutic value. Organic synthesis is employed to aid in the determination of the relationship between structure and function of these natural products. The development of synthetic methodologies in the course of total syntheses is imperative for the expansion of this highly interdisciplinary field of science. In addition to the practical applications of total syntheses, the structural complexity of natural products represents a worthwhile challenge in itself. The pursuit of concise and efficient syntheses of complex molecules is both gratifying and enjoyable.

Synthesis, crystal structure and biological activity of novel diester cyclophanes

Energy Technology Data Exchange (ETDEWEB)

Zhang, Pengfei; Yang, Bingqin; Fang, Xianwen; Cheng, Zhao; Yang, Meipan, E-mail: yangbq@nwu.edu.cn [Department of Chemistry, Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, Northwest University, Shaanxi (China)

2012-10-15

A series of novel diester cyclophanes was synthesized by esterification of 1,2-benzenedicarbonyl chloride with eight different diols under high dilution conditions. The structures of the compounds were verified by elemental analysis, {sup 1}H nuclear magnetic resonance (NMR), IR spectroscopy and high resolution mass spectrometry (HRMS). The crystal structures of two compounds were characterized by single crystal X-ray diffractometry (XRD). All the new cyclophanes were evaluated for biological activities and the results showed that some of these compounds have low antibacterial or antifungal activities (author)

Synthesis, radiolabeling and biological evaluation of [{sup 125}I]-1-[2-(benzylthio)ethyl]-4-(5-iodo-2-methoxyphenyl)piperazine as a new 5-HT{sub 1A} receptor ligand

Energy Technology Data Exchange (ETDEWEB)

Narimani, Ali [Nuclear Science and Technology Research Institute, AEOI, Tehran (Iran, Islamic Republic of). Radiation Application Research School; Islamic Azad Univ., Karaj (Iran, Islamic Republic of). Dept. of Chemistry; Sadeghzadeh, Masoud [Nuclear Science and Technology Research Institute, AEOI, Tehran (Iran, Islamic Republic of). Radiation Application Research School; Kurdtabar, Mehran [Islamic Azad Univ., Karaj (Iran, Islamic Republic of). Dept. of Chemistry

2017-07-01

5-HT{sub 1A} receptors have been implicated in the pathogenesis of a wide variety of disorders related to the serotonin receptors. WAY100635 is a well-known high affinity 5-HT{sub 1A} receptor antagonist. Many {sup 11}C and {sup 18}F radiolabeled derivatives and its radioiodinated analogues have been reported as imaging agents for 5-HT{sub 1A} receptors. In this regard, the synthesis, radiolabeling and biological evaluation of a new 5-HT{sub 1A} receptor radioligand, [{sup 125}I]-1-(2-(benzylthio)ethyl)-4-(5-iodo-2-methoxyphenyl)piperazine ([{sup 125}I]-BTE-IMPP), are described. Radioiodination of this newly synthesized compound was done by the direct aromatic electrophilic substitution via Iodo-Gen method. Radiochemical yield and radiochemical purity determined by TLC and RTLC were >70% and >95%, respectively. Biodistribution studies of [{sup 125}I]-BTE-IMPP in rats displayed relatively high uptake in hippocampus (Hip) and low uptake in cerebellum (Cer). The level of the radiotracer uptake was over threefold higher in hippocampus than in cerebellum at 30 min post-injection. Moreover, the brain to blood uptake ratio and the blocking studies results indicated prolonged retention of the radiotracer and relatively good specific binding to 5-HT{sub 1A} receptor. These findings strongly suggest that [{sup 125}I]-BTE-IMPP could be a good candidate as an in vivo marker for pharmacological study of 5-HT{sub 1A} receptors in animal models.

Solid-Phase Synthesis of Smac Peptidomimetics Incorporating Triazoloprolines and Biarylalanines

DEFF Research Database (Denmark)

Le Quement, Sebastian T.; Ishoey, Mette; Petersen, Mette T.

2011-01-01

by deactivating proteolytic caspases. The Smac protein has an antagonistic effect on IAPs, thus providing structural clues for the synthesis of new pro-apoptotic compounds. Herein, we report a solid-phase approach for the synthesis of Smac-derived tetrapeptide libraries. On the basis of a common (N......-Me)AVPF sequence, peptides incorporating triazoloprolines and biarylalanines were synthesized by means of Cu(I)-catalyzed azide–alkyne cycloaddition and Pd-catalyzed Suzuki cross-coupling reactions. Solid-phase procedures were optimized to high efficiency, thus accessing all products in excellent crude purities...... and yields (both typically above 90%). The peptides were subjected to biological evaluation in a live/dead cellular assay which revealed that structural decorations on the AVPF sequence indeed are highly important for cytotoxicity toward HeLa cells....

Synthesis and preliminary evaluation of N-acylhydrazone compounds as antibacterial and antifungal agents

International Nuclear Information System (INIS)

Cachiba, Thomas Haruo; Carvalho, Bruno Demartini; Carvalho, Diogo Teixeira; Cusinato, Marina; Prado, Clara Gaviao; Dias, Amanda Latercia Tranches

2012-01-01

We describe the synthesis and evaluation of N-acylhydrazone compounds bearing different electron-donating groups in one of its aromatic rings, obtained using a four-step synthetic route. IC 50 values against pathogenic fungi and bacteria were determined by serial microdilution. Compounds showed low activity against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. By contrast, a derivative with a meta-oriented electron-donating group showed significant activity (IC50) against Candida albicans (17 μM), C. krusei (34 μM) and C. tropicalis (17 μM). Results suggest this is a promising lead-compound for synthesis of potent antifungal agents. (author)

Synthesis of analytical and experimental data, capacity evaluation

International Nuclear Information System (INIS)

Lin Chiwenn

2001-01-01

This part of the presentation deals with the synthesis of analytical and experimental data and capacity evaluation. First, a typical test flow diagram will be discussed to identify key aspects of the test program where analysis is to be performed. Next, actual component test and analysis programs will be presented to illustrate some important parameters to be considered in the modelling process. Then, two combined test and analysis projects will be reviewed to demonstrate the potential use of substructuring in the model testing to reduce the size of the model to be tested. This will be followed by an inelastic response spectral reactor coolant loop analysis, which was used to study a high level seismic test conducted for a PWR reactor coolant system. The potential use of an improved impact calculation method will be discussed after that. As a closure to the test and analysis synthesis process, a reactor internal qualification process will be discussed. Finally, capacity evaluation will be discussed, following the requirements of ASME section III code for class 1 pressure vessel, class 1 piping which includes the reactor coolant loop piping, and the reactor internals. The subsections included in this part of presentation which cover the above mentioned subjects: typical component test and analysis results; combined test and analysis process; a simplified inelastic response spectral; analysis of reactor coolant loop; an improved impact analysis methodology; reactor coolant system and core internal qualification process; ASME section III code, design by analysis of class 1 pressure vessel; design by analysis of class 1 piping; SME section III code, design by analysis of reactor core internals

Upconversion Nanomaterials: Synthesis, Mechanism, and Applications in Sensing

Directory of Open Access Journals (Sweden)

Julia Xiaojun Zhao

2012-02-01

Full Text Available Upconversion is an optical process that involves the conversion of lower-energy photons into higher-energy photons. It has been extensively studied since mid-1960s and widely applied in optical devices. Over the past decade, high-quality rare earth-doped upconversion nanoparticles have been successfully synthesized with the rapid development of nanotechnology and are becoming more prominent in biological sciences. The synthesis methods are usually phase-based processes, such as thermal decomposition, hydrothermal reaction, and ionic liquids-based synthesis. The main difference between upconversion nanoparticles and other nanomaterials is that they can emit visible light under near infrared irradiation. The near infrared irradiation leads to low autofluorescence, less scattering and absorption, and deep penetration in biological samples. In this review, the synthesis of upconversion nanoparticles and the mechanisms of upconversion process will be discussed, followed by their applications in different areas, especially in the biological field for biosensing.

Benzodiazepine Synthesis and Rapid Toxicity Assay

Science.gov (United States)

Fletcher, James T.; Boriraj, Grit

2010-01-01

A second-year organic chemistry laboratory experiment to introduce students to general concepts of medicinal chemistry is described. Within a single three-hour time window, students experience the synthesis of a biologically active small molecule and the assaying of its biological toxicity. Benzodiazepine rings are commonly found in antidepressant…

Isotopes in molecular biology

International Nuclear Information System (INIS)

Goldfarb, P.S.G.

1988-01-01

The use of radioisotopes in molecular biology, with particular reference to the structure and functions of DNA, RNA and the cellular synthesis of proteins, is discussed. The use of labelled DNA and RNA in diagnostic techniques is presented. (U.K.)

Synthesis, chemical and biological properties of the new mono- and bis-derivatives of imidazoles

Directory of Open Access Journals (Sweden)

E. V. Welchinska

2014-12-01

Full Text Available The aim of research. The problem of finding effective antitumour medical preparation with low toxicity is an important issue of medical and pharmaceutical chemistry. Knowledge of cancer cell features and its metabolism enables to predict the direction of chemical and biological research, to conduct a targeted synthesis of potential drugs, and to assess their applicability in oncological practice as antitumor agents. The purpose of work is to explain preformed heterocycles as purines, its synthesis and investigation of chemical and biological properties. After construction of the potential active structures we proposed the new method of original derivatives synthesis which are received on the base of imidazole, from one side, and fluorocontaining common anesthetic halothane (2-bromo-1,1,1-trifluoro-2-chloroethane from other side. Molecular complex of more perspective biologically active bis-imidazole with antitumour bacterial lectine has been received. With the purpose to synthesize potential antitumour compounds on the base of halothane and imidazole, new convenient methods for the preparation of original heterocyclic derivatives of imidazole have been described. The structure and composition of synthesized compound has been confirmed by the methods of elemental analysis, IR- and NMRІН-spectra. Materials and methods. The majority of the absolute organic solvents (benzene, dimethylformamide, ethyl ester employed in the present studies were distilled before their use. Organic solvents were dried over anhydrous magnesium sulfate or metallic sodium. Gas-liquid chromatography was carried out by Perkin Elmer chromatograph with UV-detector ("Perkin", Germany. IR spectra were recorded in a UR-20 spectrometer ("Charles Ceise Hena", Germany. The 1HNMR spectra were recorded in DMSO-d6 on a 200 MHz BrakerWP-200 ("Braker", Switzerland or Varian T-60 spectrometer ("Varian", USA. Investigation of critical toxicity of new compounds was carried out at

Evaluation of impedance on biological Tissues using automatic control measurement system

Energy Technology Data Exchange (ETDEWEB)

Kil, Sang Hyeong; Shin, Dong Hoon; Lee, Seong Mo [Pusan National University, Yangsan (Korea, Republic of); Lee, Moo Seok; Kim, Sang Sik [Pusan National University, Busan (Korea, Republic of); Kim, Gun FDo; Lee, Jong Kyu [Pukyung National University, Busan (Korea, Republic of)

2015-08-15

Each biological tissue has endemic electrical characteristics owing to various differences such as those in cellular arrangement or organization form. The endemic electrical characteristics change when any biological change occurs. This work is a preliminary study surveying the changes in the electrical characteristics of biological tissue caused by radiation exposure. For protection against radiation hazards, therefore the electrical characteristics of living tissue were evaluated after development of the automatic control measurement system using LabVIEW. No alteration of biological tissues was observed before and after measurement of the electrical characteristics, and the biological tissues exhibited similar patterns. Through repeated measurements using the impedance/gain-phase analyzer, the coefficient of variation was determined as within 10%. The reproducibility impedance phase difference in electrical characteristics of the biological tissue did not change, and the tissue had resistance. The absolute value of impedance decreased constantly in proportion to the frequency. It has become possible to understand the electrical characteristics of biological tissues through the measurements made possible by the use of the developed.

Evaluation of impedance on biological Tissues using automatic control measurement system

International Nuclear Information System (INIS)

Kil, Sang Hyeong; Shin, Dong Hoon; Lee, Seong Mo; Lee, Moo Seok; Kim, Sang Sik; Kim, Gun FDo; Lee, Jong Kyu

2015-01-01

Each biological tissue has endemic electrical characteristics owing to various differences such as those in cellular arrangement or organization form. The endemic electrical characteristics change when any biological change occurs. This work is a preliminary study surveying the changes in the electrical characteristics of biological tissue caused by radiation exposure. For protection against radiation hazards, therefore the electrical characteristics of living tissue were evaluated after development of the automatic control measurement system using LabVIEW. No alteration of biological tissues was observed before and after measurement of the electrical characteristics, and the biological tissues exhibited similar patterns. Through repeated measurements using the impedance/gain-phase analyzer, the coefficient of variation was determined as within 10%. The reproducibility impedance phase difference in electrical characteristics of the biological tissue did not change, and the tissue had resistance. The absolute value of impedance decreased constantly in proportion to the frequency. It has become possible to understand the electrical characteristics of biological tissues through the measurements made possible by the use of the developed.

Studies towards a total synthesis of tagetitoxin

OpenAIRE

Mahoney, Brian

2017-01-01

Tagetitoxin was first isolated over thirty five years ago and a total synthesis has not been achieved to date. A vast amount of research has been carried out on the biological activity of tagetitoxin with hundreds of literature reports. However, very few papers have been published regarding the synthesis and within this thesis we will explore a number of synthetic pathways some towards tagetitoxin. The first chapter reviews previous developments regarding the total synthesis of...

Evaluating children's conservation biology learning at the zoo.

Science.gov (United States)

Jensen, Eric

2014-08-01

Millions of children visit zoos every year with parents or schools to encounter wildlife firsthand. Public conservation education is a requirement for membership in professional zoo associations. However, in recent years zoos have been criticized for failing to educate the public on conservation issues and related biological concepts, such as animal adaptation to habitats. I used matched pre- and postvisit mixed methods questionnaires to investigate the educational value of zoo visits for children aged 7-15 years. The questionnaires gathered qualitative data from these individuals, including zoo-related thoughts and an annotated drawing of a habitat. A content analysis of these qualitative data produced the quantitative data reported in this article. I evaluated the relative learning outcomes of educator-guided and unguided zoo visits at London Zoo, both in terms of learning about conservation biology (measured by annotated drawings) and changing attitudes toward wildlife conservation (measured using thought-listing data). Forty-one percent of educator-guided visits and 34% of unguided visits resulted in conservation biology-related learning. Negative changes in children's understanding of animals and their habitats were more prevalent in unguided zoo visits. Overall, my results show the potential educational value of visiting zoos for children. However, they also suggest that zoos' standard unguided interpretive materials are insufficient for achieving the best outcomes for visiting children. These results support a theoretical model of conservation biology learning that frames conservation educators as toolmakers who develop conceptual resources to enhance children's understanding of science. © 2014 Society for Conservation Biology.

Design, synthesis, X-ray studies, and biological evaluation of novel macrocyclic HIV-1 protease inhibitors involving the P1'-P2' ligands

Energy Technology Data Exchange (ETDEWEB)

Ghosh, Arun K.; Sean Fyvie, W.; Brindisi, Margherita; Steffey, Melinda; Agniswamy, Johnson; Wang, Yuan-Fang; Aoki, Manabu; Amano, Masayuki; Weber, Irene T.; Mitsuya, Hiroaki

2017-11-01

Design, synthesis, and evaluation of a new class of HIV-1 protease inhibitors containing diverse flexible macrocyclic P1'-P2' tethers are reported. Inhibitor 5a with a pyrrolidinone-derived macrocycle exhibited favorable enzyme inhibitory and antiviral activity (Ki = 13.2 nM, IC50 = 22 nM). Further incorporation of heteroatoms in the macrocyclic skeleton provided macrocyclic inhibitors 5m and 5o. These compounds showed excellent HIV-1 protease inhibitory (Ki = 62 pM and 14 pM, respectively) and antiviral activity (IC50 = 5.3 nM and 2.0 nM, respectively). Inhibitor 5o also remained highly potent against a DRV-resistant HIV-1 variant.

Evaluation of radiobiological effects in 3 distinct biological models

International Nuclear Information System (INIS)

Lemos, J.; Costa, P.; Cunha, L.; Metello, L.F.; Carvalho, A.P.; Vasconcelos, V.; Genesio, P.; Ponte, F.; Costa, P.S.; Crespo, P.

2015-01-01

Full text of publication follows. The present work aims at sharing the process of development of advanced biological models to study radiobiological effects. Recognizing several known limitations and difficulties of the current monolayer cellular models, as well as the increasing difficulties to use advanced biological models, our group has been developing advanced biological alternative models, namely three-dimensional cell cultures and a less explored animal model (the Zebra fish - Danio rerio - which allows the access to inter-generational data, while characterized by a great genetic homology towards the humans). These 3 models (monolayer cellular model, three-dimensional cell cultures and zebra fish) were externally irradiated with 100 mGy, 500 mGy or 1 Gy. The consequences of that irradiation were studied using cellular and molecular tests. Our previous experimental studies with 100 mGy external gamma irradiation of HepG2 monolayer cells showed a slight increase in the proliferation rate 24 h, 48 h and 72 h post irradiation. These results also pointed into the presence of certain bystander effects 72 h post irradiation, constituting the starting point for the need of a more accurate analysis realized with this work. At this stage, we continue focused on the acute biological effects. Obtained results, namely MTT and clonogenic assays for evaluating cellular metabolic activity and proliferation in the in vitro models, as well as proteomics for the evaluation of in vivo effects will be presented, discussed and explained. Several hypotheses will be presented and defended based on the facts previously demonstrated. This work aims at sharing the actual state and the results already available from this medium-term project, building the proof of the added value on applying these advanced models, while demonstrating the strongest and weakest points from all of them (so allowing the comparison between them and to base the subsequent choice for research groups starting

Selected heterocyclic compounds as antioxidants. Synthesis and biological evaluation.

Science.gov (United States)

Tsolaki, E; Nobelos, P; Geronikaki, A; Rekka, E A

2014-01-01

Reactive oxygen species, oxidative stress, and oxidative damage are increasingly assigned important roles as harmful factors in pathological conditions and ageing. ROS are potentially reactive molecules derived from the reduction of molecular oxygen in the course of aerobic metabolism. ROS can also be produced through a variety of enzymes. Under normal circumstances, ROS concentrations are tightly controlled by physiological antioxidants. When excessively produced, or when antioxidants are depleted, ROS can impose oxidative damage to lipids, proteins, sugars and DNA. This reduction-oxidation imbalance, called oxidative stress, can subsequently contribute to the development and progression of tissue damage and play a role in the pathology of various diseases. An antioxidant is defined as "any substance that, when present at low concentrations compared with those of a substrate, significantly delays, prevents or removes oxidative damage to this target molecule". Despite evidence that oxidative damage contributes to a wide range of clinically important conditions, few antioxidants act as effective drugs in vivo. Inter alia, the difficulty of measuring antioxidant efficacy in vivo makes the interpretation of results from clinical trials difficult. A large number of synthetic compounds have been reported to possess antioxidant activity. Several of them derive from natural antioxidants, others have various structures. In this review, some of the most often reported classes of heterocyclic antioxidant compounds, as well as methods for evaluation of their antioxidant activity are discussed.

Evaluation of biological attributes of soil type latossol under agroecological production

Directory of Open Access Journals (Sweden)

Marisol Rivero Herrada

2016-10-01

Full Text Available Biological soil attributes have shown to be good indicators of soil changes as a result of the management function. The aim of this study was to evaluate the effect of using cover crops, as well as planting and tillage systems on the biological attributes of a yellowish red latosol soil. Soil samples were taken at 0 to 0.10 m depth, seven days before the bean harvest. Microbial biomass carbon and nitrogen, basal soil respiration, metabolic ratio and total enzyme activity were evaluated in this study. The best agroecological management was achieved under the association of the ground cover with millet and in direct seeding because they showed higher soil microbial biomass carbon and nitrogen content and lower metabolic quotient, being pork bean the best plant coverage. All biological soil attributes were sensitive to the tillage system, which showed the best results of the total enzyme activity and of the soil metabolic quotient which resulted to be the most efficient.

Synthesis and biological evaluation of certain 2-H-Pyran-2-Ones and some derived 1-H-Pyridin-2-One analogs as antimicrobial agents

International Nuclear Information System (INIS)

Faidallah, Hassan M.; Al-Saadi, Mohammad S.; Rostom, Sherif A. F.

2008-01-01

Pyran-2-one and pyridine-2-one analogs are known to be biological versatile compounds possessing variety of pharmacological activities. Some 4-(4-nitrophenyl)-5, 6-diphenyl-pyran-2-ones and their 1H-pyridin-2-oneanalogs were synthesized and evaluated for their in vitro intermediates and target compounds were discussed. The results evaluated that some compounds exhibited promising antibacterial and antifungal activities. Compound 8; 1-hydroxy-4-(4-nitrophenyl)-5, 6-diphenyl-1H-pyridin-2-one; showed the most potent broad spectrum antimicrobial activity. 1-Methyl-4-(4-nitrophenyl)-5, 6-diphenyl-1H-pyridin-2-thione 12; was able to exert weak growth inhibitory effect against the Mycobacterium tuberculosis. (author)

Convenient one-step synthesis of 5-carboxy-seminaphthofluoresceins

DEFF Research Database (Denmark)

Hammershøj, Peter; Thyhaug, Erling; Harris, Pernille

2017-01-01

The one-step synthesis and characterization of a series of regioisomerically pure 5-carboxy-seminaphthofluoresceins (5-carboxy-SNAFLs) is reported. The optical properties were determined in aqueous buffer at around biological pH, and highly pH sensitive, large Stokes-shift fluorophores with emiss......The one-step synthesis and characterization of a series of regioisomerically pure 5-carboxy-seminaphthofluoresceins (5-carboxy-SNAFLs) is reported. The optical properties were determined in aqueous buffer at around biological pH, and highly pH sensitive, large Stokes-shift fluorophores...

Coriandrum sativum mediated synthesis of silver nanoparticles and evaluation of their biological characteristics

Science.gov (United States)

Senthilkumar, N.; Aravindhan, V.; Ruckmani, K.; Vetha Potheher, I.

2018-05-01

Silver (Ag) nanoparticles (NPs) were prepared by percolated green synthesis method using Coriandrum sativum leaf, root, seed and stem extracts and reported its antibacterial activity. The synthesized Ag NPs were confirmed by UV–visible Spectroscopy, Powder x-ray Diffraction (PXRD), Fourier Transform Infra Red (FT-IR) Spectroscopy analyzes. The Maximum absorbance observed around 400–450 nm reveal the characteristic absorbance of Ag NPs. The Dynamic Light Scattering (DLS) analysis shows the stability of synthesized NPs with average size varying from 35 to 53 nm and also zeta potential stability varying from ‑20 to ‑30 mV. The cubic structure, crystalline nature and purity of the material was confirmed by powder x-ray diffraction studies. FT-IR spectrum shows the presence of various functional groups in the resultant material. The Field Emission Scanning Electron Microscopy (FESEM) image shows the surface morphology of the synthesized NPs and the Energy Dispersive x-ray Analysis (EDAX) confirms the presence of silver metal ions. The Coriandrum sativum aqueous extract exhibited excellent antimicrobial activity against Klebsiella pneumoniae (Gram -ve) bacteria. Numerous studies have been made previously in our field of study but optimization has not been carried out by both extract (different parts like leaf, root, seed and stem) and without addition of any external source such as chemicals, heat etc.

Glutamatergic clock output stimulates melatonin synthesis at night

NARCIS (Netherlands)

Perreau-Lenz, Stéphanie; Kalsbeek, Andries; Pévet, Paul; Buijs, Ruud M.

2004-01-01

The rhythm of melatonin synthesis in the rat pineal gland is under the control of the biological clock, which is located in the suprachiasmatic nucleus of the hypothalamus (SCN). Previous studies demonstrated a daytime inhibitory influence of the SCN on melatonin synthesis, by using

Stereoselective synthesis of hernandulcin, peroxylippidulcine A, lippidulcines A, B and C and taste evaluation

Directory of Open Access Journals (Sweden)

Marco G. Rigamonti

2015-11-01

Full Text Available The first stereoselective synthesis of lippidulcines A, B and C has been accomplished starting from (+-hernandulcin, which has been prepared on a multigram scale. The previously assigned absolute configurations have been confirmed. The key steps of this synthesis are based on a modified version of the Kornblum–DeLaMare rearrangement, and on a highly regioselective and stereoselective ketone reduction with the MeCBS reagent. The taste evaluations indicate that none of these sesquiterpenes are sweet, instead the lippidulcine A is a cooling agent with a mint after taste.

Benzoheterocyclic amodiaquine analogues with potent antiplasmodial activity: synthesis and pharmacological evaluation.

Science.gov (United States)

Ongarora, Dennis S B; Gut, Jiri; Rosenthal, Philip J; Masimirembwa, Collen M; Chibale, Kelly

2012-08-01

The synthesis and evaluation of antiplasmodial activity of benzothiazole, benzimidazole, benzoxazole and pyridine analogues of amodiaquine is hereby reported. Benzothiazole and benzoxazole analogues with a protonatable tertiary nitrogen atom possessed excellent activity against the W2 and K1 chloroquine resistant strains of Plasmodium falciparum, with IC(50)s ranging from 7 to 22 nM. Copyright © 2012 Elsevier Ltd. All rights reserved.

e-Biologics: Fabrication of Sustainable Electronics with "Green" Biological Materials.

Science.gov (United States)

Lovley, Derek R

2017-06-27

The growing ubiquity of electronic devices is increasingly consuming substantial energy and rare resources for materials fabrication, as well as creating expansive volumes of toxic waste. This is not sustainable. Electronic biological materials (e-biologics) that are produced with microbes, or designed with microbial components as the guide for synthesis, are a potential green solution. Some e-biologics can be fabricated from renewable feedstocks with relatively low energy inputs, often while avoiding the harsh chemicals used for synthesizing more traditional electronic materials. Several are completely free of toxic components, can be readily recycled, and offer unique features not found in traditional electronic materials in terms of size, performance, and opportunities for diverse functionalization. An appropriate investment in the concerted multidisciplinary collaborative research required to identify and characterize e-biologics and to engineer materials and devices based on e-biologics could be rewarded with a new "green age" of sustainable electronic materials and devices. Copyright © 2017 Lovley.

Mechanochemical Synthesis, In vivo Anti-malarial and Safety Evaluation of Amodiaquine-zinc Complex

Directory of Open Access Journals (Sweden)

Arise Rotimi Olusanya

2017-09-01

Full Text Available So far, some prospective metal-based anti-malarial drugs have been developed. The mechanochemical synthesis and characterization of Zn (II complex with amodiaquine and its anti-malarial efficacy on Plasmodium berghei-infected mice and safety evaluation were described in this study.

Synthesis and Antimicrobial Evaluation of Some Novel Thiazole, Pyridone, Pyrazole, Chromene, Hydrazone Derivatives Bearing a Biologically Active Sulfonamide Moiety

Science.gov (United States)

Darwish, Elham S.; Abdel Fattah, Azza M.; Attaby, Fawzy A.; Al-Shayea, Oqba N.

2014-01-01

This study aimed for the synthesis of new heterocyclic compounds incorporating sulfamoyl moiety suitable for use as antimicrobial agents via a versatile, readily accessible N-[4-(aminosulfonyl)phenyl]-2-cyanoacetamide (3). The 2-pyridone derivatives were obtained via reaction of cyanoacetamide with acetylacetone or arylidenes malononitrile. Cycloaddition reaction of cyanoacetamide with salicyaldehyde furnished chromene derivatives. Diazotization of 3 with the desired diazonium chloride gave the hydrazone derivatives 13a–e. Also, the reactivity of the hydrazone towards hydrazine hydrate to give Pyrazole derivatives was studied. In addition, treatment of 3 with elemental sulfur and phenyl isothiocyanate or malononitrile furnished thiazole and thiophene derivatives respectively. Reaction of 3 with phenyl isothiocyanate and KOH in DMF afforded the intermediate salt 17 which reacted in situ with 3-(2-bromoacetyl)-2H-chromen-2-one and methyl iodide afforded the thiazole and ketene N,S-acetal derivatives respectively. Finally, reaction of 3 with carbon disulfide and 1,3-dibromopropane afforded the N-[4-(aminosulfonyl) phenyl]-2-cyano-2-(1,3-dithian-2-ylidene)acetamide product 22. All newly synthesized compounds were elucidated by considering the data of both elemental and spectral analysis. The compounds were evaluated for both their in vitro antibacterial and antifungal activities and showed promising results. PMID:24445259

Synthesis and Antimicrobial Evaluation of Some Novel Thiazole, Pyridone, Pyrazole, Chromene, Hydrazone Derivatives Bearing a Biologically Active Sulfonamide Moiety

Directory of Open Access Journals (Sweden)

Elham S. Darwish

2014-01-01

Full Text Available This study aimed for the synthesis of new heterocyclic compounds incorporating sulfamoyl moiety suitable for use as antimicrobial agents via a versatile, readily accessible N-[4-(aminosulfonylphenyl]-2-cyanoacetamide (3. The 2-pyridone derivatives were obtained via reaction of cyanoacetamide with acetylacetone or arylidenes malononitrile. Cycloaddition reaction of cyanoacetamide with salicyaldehyde furnished chromene derivatives. Diazotization of 3 with the desired diazonium chloride gave the hydrazone derivatives 13a–e. Also, the reactivity of the hydrazone towards hydrazine hydrate to give Pyrazole derivatives was studied. In addition, treatment of 3 with elemental sulfur and phenyl isothiocyanate or malononitrile furnished thiazole and thiophene derivatives respectively. Reaction of 3 with phenyl isothiocyanate and KOH in DMF afforded the intermediate salt 17 which reacted in situ with 3-(2-bromoacetyl-2H-chromen-2-one and methyl iodide afforded the thiazole and ketene N,S-acetal derivatives respectively. Finally, reaction of 3 with carbon disulfide and 1,3-dibromopropane afforded the N-[4-(aminosulfonyl phenyl]-2-cyano-2-(1,3-dithian-2-ylideneacetamide product 22. All newly synthesized compounds were elucidated by considering the data of both elemental and spectral analysis. The compounds were evaluated for both their in vitro antibacterial and antifungal activities and showed promising results.

Synthesis, conformational analysis, and biological activity of new analogues of thiazole-4-carboxamide adenine dinucleotide (TAD) as IMP dehydrogenase inhibitors.

Science.gov (United States)

Franchetti, Palmarisa; Cappellacci, Loredana; Pasqualini, Michela; Petrelli, Riccardo; Jayaprakasan, Vetrichelvan; Jayaram, Hiremagalur N; Boyd, Donald B; Jain, Manojkumar D; Grifantini, Mario

2005-03-15

Thiazole-4-carboxamide adenine dinucleotide (TAD) analogues T-2'-MeAD (1) and T-3'-MeAD (2) containing, respectively, a methyl group at the ribose 2'-C-, and 3'-C-position of the adenosine moiety, were prepared as potential selective human inosine monophosphate dehydrogenase (IMPDH) type II inhibitors. The synthesis of heterodinucleotides was carried out by CDI-catalyzed coupling reaction of unprotected 2'-C-methyl- or 3'-C-methyl-adenosine 5'-monophosphate with 2',3'-O-isopropylidene-tiazofurin 5'-monophosphate, and then deisopropylidenation. Biological evaluation of dinucleotides 1 and 2 as inhibitors of recombinant human IMPDH type I and type II resulted in a good activity. Inhibition of both isoenzymes by T-2'-MeAD and T-3'-MeAD was noncompetitive with respect to NAD substrate. Binding of T-3'-MeAD was comparable to that of parent compound TAD, while T-2'-MeAD proved to be a weaker inhibitor. However, no significant difference was found in inhibition of the IMPDH isoenzymes. T-2'-MeAD and T-3'-MeAD were found to inhibit the growth of K562 cells (IC(50) 30.7 and 65.0muM, respectively).

Synthesis, characterization and biological evaluation of ...

Indian Academy of Sciences (India)

Pyrimidine derivatives are important class of com- pounds which display number of pharmacological pro- perties including antiviral, antitumour, antibacterial and antihypertensive effects.1–3 In recent years, interest has also been focused on aza-analogs of 1,4-dihydro- pyridines such as dihydropyrimidines (DHPMs), which.

Substituted Pyrazinecarboxamides: Synthesis and Biological Evaluation

Directory of Open Access Journals (Sweden)

Katarina Kralova

2006-03-01

Full Text Available Condensation of the corresponding chlorides of some substituted pyrazine-2-carboxylic acids (pyrazine-2-carboxylic acid, 6-chloropyrazine-2-carboxylic acid, 5-tert-butylpyrazine-2-carboxylic acid or 5-tert-butyl-6-chloropyrazine-2-carboxylic acid withvarious ring-substituted aminothiazoles or anilines yielded a series of amides. Thesyntheses, analytical and spectroscopic data of thirty newly prepared compounds arepresented. Structure-activity relationships between the chemical structures and the anti-mycobacterial, antifungal and photosynthesis-inhibiting activity of the evaluatedcompounds are discussed. 3,5-Bromo-4-hydroxyphenyl derivatives of substitutedpyrazinecarboxylic acid, 16-18, have shown the highest activity against Mycobacteriumtuberculosis H37Rv (54-72% inhibition. The highest antifungal effect againstTrichophyton mentagrophytes, the most susceptible fungal strain tested, was found for5-tert-butyl-6-chloro-N-(4-methyl-1,3-thiazol-2-ylpyrazine-2-carboxamide (8, MIC =31.25 μmol·mL-1. The most active inhibitors of oxygen evolution rate in spinachMolecules 2006, 11 243 chloroplasts were the compounds 5-tert-butyl-6-chloro-N-(5-bromo-2-hydroxyphenyl- pyrazine-2-carboxamide (27, IC50 = 41.9 μmol·L-1 and 5-tert-butyl-6-chloro-N-(1,3- thiazol-2-yl-pyrazine-2-carboxamide (4, IC50 = 49.5 μmol·L-1.

Weissella oryzae DC6-facilitated green synthesis of silver nanoparticles and their antimicrobial potential.

Science.gov (United States)

Singh, Priyanka; Kim, Yeon J; Wang, Chao; Mathiyalagan, Ramya; Yang, Deok C

2016-09-01

Nanoparticles and nanomaterials are at the prominent edge of the rapidly developing field of nanotechnology. Recently, nanoparticle synthesis using biological resources has been found to be a new area with considerable prospects for development. Biological systems are the masters of ambient condition chemistry and are able to synthesize nanoparticles by utilizing metal salts. In the perspective of the current initiative to develop green technologies for the synthesis of nanoparticles, microorganisms are of considerable interest. Thus, the present study describes a bacterial strain-Weissella oryzae DC6-isolated from mountain ginseng, for the green and facile synthesis of silver nanoparticles. The particles were synthesized effectively without the need for any supplementary modification to maintain stability. The synthesized nanoparticles were evaluated by several instrumental techniques, comprising ultraviolet-visible spectrophotometry, field emission transmission electron microscopy, energy dispersive X-ray spectroscopy, elemental mapping, X-ray diffraction, and dynamic light scattering. In addition, the biosynthesized silver nanoparticles were explored for their antimicrobial activity against clinical pathogens including Vibrio parahaemolyticus, Bacillus cereus, Bacillus anthracis, Staphylococcus aureus, Escherichia coli, and Candida albicans. Furthermore, the potential of nanoparticles has been observed for biofilm inhibition against Staphylococcus aureus and Pseudomonas aeruginosa. Thus, the synthesis of silver nanoparticles by the strain W. oryzae DC6 may serve as a simple, green, cost-effective, consistent, and harmless method to produce antimicrobial silver nanoparticles.

An algorithm to biological tissues evaluation in pediatric examinations

International Nuclear Information System (INIS)

Souza, R.T.F.; Miranda, J.R.A.; Alvarez, M.; Velo, A.F.; Pina, D.R.

2011-01-01

A prerequisite for the construction of phantoms is the quantification of the average thickness of biological tissues and the equivalence of these simulators in simulator material thicknesses. This study aim to develop an algorithm to classify and quantify tissues, based on normal distribution of CT numbers of anatomical structures found in the mean free path of the X-rays beam, using the examination histogram to carry out this evaluation. We have considered an algorithm for the determination of the equivalent biological tissues thickness from histograms. This algorithm classifies different biological tissues from tomographic exams in DICOM format and calculates the average thickness of these tissues. The founded results had revealed coherent with literature, presenting discrepancies of up to 21,6%, relative to bone tissue, analyzed for anthropomorphic phantom (RANDO). These results allow using this methodology in livings tissues, for the construction of thorax homogeneous phantoms, of just born and suckling patients, who will be used later in the optimization process of pediatrics radiographic images. (author)

Biomimetic synthesis and biocompatibility evaluation of carbonated apatites template-mediated by heparin

Energy Technology Data Exchange (ETDEWEB)

Deng, Yi [Department of Oral and Maxillofacial Surgery, Laboratory of Interdisciplinary Studies, School and Hospital of Stomatology, Peking University, Beijing 100081 (China); Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); Sun, Yuhua [Department of Oral and Maxillofacial Surgery, Laboratory of Interdisciplinary Studies, School and Hospital of Stomatology, Peking University, Beijing 100081 (China); Chen, Xiaofang [Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); Zhu, Peizhi, E-mail: pzzhu@umich.edu [Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055 (United States); Wei, Shicheng, E-mail: sc-wei@pku.edu.cn [Department of Oral and Maxillofacial Surgery, Laboratory of Interdisciplinary Studies, School and Hospital of Stomatology, Peking University, Beijing 100081 (China); Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China)

2013-07-01

Biomimetic synthesis of carbonated apatites with good biocompatibility is a promising strategy for the broadening application of apatites for bone tissue engineering. Most researchers were interested in collagen or gelatin-based templates for synthesis of apatite minerals. Inspired by recent findings about the important role of polysaccharides in bone biomineralization, here we reported that heparin, a mucopolysaccharide, was used to synthesize carbonated apatites in vitro. The results indicated that the Ca/P ratio, carbon content, crystallinity and morphology of the apatites varied depending on the heparin concentration and the initial pH value. The morphology of apatite changed from flake-shaped to needle-shaped, and the degree of crystallinity decreased with the increasing of heparin concentration. Biocompatibility of the apatites was tested by proliferation and alkaline phosphatase activity of MC3T3-E1 cells. The results suggested that carbonated apatites synthesized in the presence of heparin were more favorable to the proliferation and differentiation of MC3T3-E1 cells compared with traditional method. In summary, the heparin concentration and the initial pH value play a key role in the chemical constitution and morphology, as well as biological properties of apatites. These biocompatible nano-apatite crystals hold great potential to be applied as bioactive materials for bone tissue engineering. - Highlights: • Heparin was used as a template to synthesize needle-shaped nano-apatite. • Changing the pH value and concentration led to different properties of apatite. • Apatite prepared by heparin was more favorable to the osteogenic differentiation. • Possible synthesis mechanism of apatite templated by heparin was described.

New enamine derivatives of lapachol and biological activity

Directory of Open Access Journals (Sweden)

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.

Synthesis and biological evaluation of boronated polyglycerol dendrimers as potential agent for neutron capture therapy

International Nuclear Information System (INIS)

Silva, Gerald S.; Camillo, Maria A.P.; Higa, Olga Z.; Pugliesi, Reynaldo; Fermamdes, Edson G.R.; Queiroz, Alvaro A.A. de

2005-01-01

In this work, the polyglycerol dendrimer (PGLD) generation 5 was used to obtain a boronated macromolecule for boron neutron capture therapy. The PGLD dendrimer was synthesized by the ring opening polymerization of deprotonated glycidol using polyglycerol as core functionality in a step-growth processes denominated divergent synthesis. The PGLD dendritic structure was confirmed by gel permeation chromatography, nuclear magnetic resonance ( 1 H-NMR, 13 C-NMR) and matrix assisted laser desorption/ionization techniques. The synthesized dendrimer presented low dispersion in molecular weights (M w /M n = 1.05) and a degree of branching of 0.82, which characterize the polymer dendritic structure. Quantitative neutron capture radiography was used to investigate the boron-10 enrichment of the polyglycerol dendrimer. The in vitro cytotoxicity to Chinese hamster ovary cells of 10 B-PGLD dendrimer indicate lower cytotoxicity, suggesting that the macromolecule is a biocompatible material. (author)

Synthesis and characterization of polyglycerols dendrimers for applications in tissue engineering biological

Energy Technology Data Exchange (ETDEWEB)

Passos, E.D.; Queiroz, A.A.A. de [Universidade Federal de Itajuba (UNIFEI), MG (Brazil)

2014-07-01

Full text: Introduction: Over the last twenty years is the growing development in the manufacture of synthetic scaffold in tissue engineering applications. These new materials are based on polyglycerol dendrimers (PGLD's). PGLD's are highly functional polymers with hydroxymethyl side groups, fulfill all structural prerequisites to replace poly(ethylene glycol)s in medical applications. Furthermore, since these materials are based on naturally occurring compounds that degrades over time in the body and can be safely excreted. The objective of this work was the synthesis, physicochemical, biological characterization of HPGL's with potential use as scaffolds in tissue engineering. HPGL's with oligomeric cores, of diglycerol triglycerol and tetraglycerol was used. Theoretical and Experimental Simulation Details: The synthesis of PGLD procedures involves the etherification of glycerol through anionic polymerization of glycidol. The PGLD's were characterized by chromatographic techniques (SEC and HPLC), spectroscopic (FTIR, 1H-NMR and 13C - NMR) electrochemical (zeta potential) and thermal analysis (DSC and TGA) techniques. The structure- activity relationships (SAR's) of compound prototype and its analogs were studied to determine the generation number (G) of the molecule responsible for the biological activity on the adhesion and cell proliferation process. A detailed study of the structure of PGLD's of G=0-4 was performed using the Hyperchem 7. 5 and Gromacs 4 software packages. The biocompatibility studies were studied by scanning electron microscopy (SEM) and fluorescence microscopy (EPF) technique after PGLD (G=0-4) blood contact. The overall electro-negativity/total charge density, dipole moment, frontier orbital's (HOMO - LUMO) and electrostatic potential maps (EPM) were calculated. The most stable form of the resulting compounds was determined by estimating the hydration energy and energy conformation. Results and

Synthesis, reactions and biological activity of some new bis-heterocyclic ring compounds containing sulphur atom

Science.gov (United States)

2013-01-01

Background The derivatives of thieno[2,3-b]thiophene belong to a significant category of heterocyclic compounds, which have shown a wide spectrum of medical and industrial application. Results A new building block with two electrophilic center of thieno[2,3-b]thiophene derivatives 2 has been reported by one-pot reaction of diketone derivative 1 with Br2/AcOH in excellent yield. A variety of heteroaromatics having bis(1H-imidazo[1,2a] benzimidazole), bis(1H-imidazo[1,2-b][1,2,4]triazole)-3-methyl-4-phenylthieno[2,3-b]thiophene derivatives, dioxazolo-, dithiazolo-, and 1H-imidazolo-3-methyl-4-phenylthieno[2,3-b]thiophene derivatives as well pyrrolo, thiazolo -3-methyl-4-phenylthieno[2,3-b]thiophene derivatives have been designed, synthesized, characterized, and evaluated for their biological activity. Compounds 3–9 showed good bioassay result. These new derivatives were evaluated for anti-cancer activity against PC-3 cell lines, in vitro antioxidant potential and β-glucuronidase and α-glucosidase inhibitory activities. Compound 3 (IC50 = 56.26 ± 3.18 μM) showed a potent DPPH radical scavenging antioxidant activity and found to be more active than standard N-acetylcystein (IC50 = 105.9 ± 1.1 μM). Compounds 8a (IC50 = 13.2 ± 0.34 μM) and 8b (IC50 = 14.1 ± 0.28 μM) found as potent inhibitor of α-glucusidase several fold more active than the standard acarbose (IC50 = 841 ± 1.73 μM). Most promising results were obtained in β-glucuronidase enzyme inhibition assay. Compounds 5 (IC50 = 0.13 ± 0.019 μM), 6 (IC50 = 19.9 ± 0.285 μM), 8a (IC50 = 1.2 ± 0.0785 μM) and 9 (IC50 = 0.003 ± 0.09 μM) showed a potent inhibition of β-glucuronidase. Compound 9 was found to be several hundred fold more active than standard D-Saccharic acid 1,4-lactone (IC50 = 45.75 ± 2.16 μM). Conclusions Synthesis, characterization, and in vitro biological activity of a series of

Purification of benzoyl-mercapto-acetyl-tri-glycine and ethyl cysteinate dimer complemented with biological evaluations

International Nuclear Information System (INIS)

Robles, A.; Ramos, B.; Herrera, J.

1999-01-01

Purification of benzoyl-mercaptoacetyl triglycine (MAG3) and ethyl cysteinate dimer (L,L-ECD) has been conducted through fractionated recrystallization of its impurities and isomers; biological behavior of the main isomers has been evaluated through biological distribution in mice. Chemical purity of synthesized MAG3 is 69,9%; after purification, 98, 12% is obtained from the compound with adequate biological distribution; fusion points range between 194 and 196 o C before and after purification; recrystallization yields is 12%. Radiochemical purity of testing lot is 98%. In biological evaluations conducted in mice, injection dose percentages for the purest one, after 5 minutes, is 31,20% in kidneys and 1,14% in the liver. Chemical purity of synthesized ECD is 80,29%; after purification, 98,76% is obtained from the isomer with adequate biological activity; fusion points range between 195 and 197 o C; yield percentage in recrystallization is 29%. radiochemical purity of testing lot is 97%; in biological evaluations conducted in mice, injection dose percentages for the purest one, after 5 minutes, is 1,37% in the brain, 25,70% in the liver and 13,40% in kidneys

Synthesis and biological evaluation of novel heterocyclic derivatives of combretastatin A-4.

Science.gov (United States)

Nguyen, Thi Thanh Binh; Lomberget, Thierry; Tran, Ngoc Chau; Colomb, Evelyne; Nachtergaele, Lore; Thoret, Sylviane; Dubois, Joëlle; Guillaume, Joren; Abdayem, Rawad; Haftek, Marek; Barret, Roland

2012-12-01

A novel series of combretastatin A-4 heterocyclic analogues was prepared by replacement of the B ring with indole, benzofurane or benzothiophene, attached at the C2 position. These compounds were evaluated for their abilities to inhibit tubulin assembly: derivative cis3b, having a benzothiophene, showed an activity similar to those of colchicine or deoxypodophyllotoxine. The antiproliferative and antimitotic properties of cis3b against keratinocyte cancer cell lines were also evaluated and the intracellular organization of microtubules in the cells after treatment with both stereoisomers of 3b was also determined, using confocal microscopy. Copyright © 2012 Elsevier Ltd. All rights reserved.

A bio-inspired approach for in situ synthesis of tunable adhesive

International Nuclear Information System (INIS)

Sun, Leming; Yi, Sijia; Wang, Yongzhong; Pan, Kang; Zhong, Qixin; Zhang, Mingjun

2014-01-01

Inspired by the strong adhesive produced by English ivy, this paper proposes an in situ synthesis approach for fabricating tunable nanoparticle enhanced adhesives. Special attention was given to tunable features of the adhesive produced by the biological process. Parameters that may be used to tune properties of the adhesive will be proposed. To illustrate and validate the proposed approach, an experimental platform was presented for fabricating tunable chitosan adhesive enhanced by Au nanoparticles synthesized in situ. This study contributes to a bio-inspired approach for in situ synthesis of tunable nanocomposite adhesives by mimicking the natural biological processes of ivy adhesive synthesis. (paper)

Design, synthesis, and initial evaluation of D-glyceraldehyde crosslinked gelatin-hydroxyapatite as a potential bone graft substitute material

Science.gov (United States)

Florschutz, Anthony Vatroslav

Utilization of bone grafts for the treatment of skeletal pathology is a common practice in orthopaedic, craniomaxillofacial, dental, and plastic surgery. Autogenous bone graft is the established archetype but has disadvantages including donor site morbidity, limited supply, and prolonging operative time. In order to avoid these and other issues, bone graft substitute materials are becoming increasingly prevalent among surgeons for reconstructing skeletal defects and arthrodesis applications. Bone graft substitutes are biomaterials, biologics, and guided tissue/bone regenerative devices that can be used alone or in combinations as supplements or alternatives to autogenous bone graft. There is a growing interest and trend to specialize graft substitutes for specific indications and although there is good rationale for this indication-specific approach, the development and utility of a more universal bone graft substitute may provide a better answer for patients and surgeons. The aim of the present research focuses on the design, synthesis, and initial evaluation of D-glyceraldehyde crosslinked gelatin-hydroxyapatite composites for potential use as a bone graft substitutes. After initial establishment of rational material design, gelatinhydroxyapatite scaffolds were fabricated with different gelatin:hydroxyapatite ratios and crosslinking concentrations. The synthesized scaffolds were subsequently evaluated on the basis of their swelling behavior, porosity, density, percent composition, mechanical properties, and morphology and further assessed with respect to cell-biomaterial interaction and biomineralization in vitro. Although none of the materials achieved mechanical properties suitable for structural graft applications, a reproducible material design and synthesis was achieved with properties recognized to facilitate bone formation. Select scaffold formulations as well as a subset of scaffolds loaded with recombinant human bone morphogenetic protein-2 were

A Concise Total Synthesis of S-(+)-Tylophorine

Institute of Scientific and Technical Information of China (English)

JIN,Zhong; WANG,Qing-Min; LI,Hao; LIU,Yu-Xiu; LI,Shi-Pu; HUANG,Run-Qiu

2004-01-01

@@ Phenanthroindolizidine alkaloids, which exhibit extensively biological properties, are widely present at various plants of the Asclepiadaceae family.[1] The significantly biological importance of these natural products has attracted considerable synthetic efforts.[2] We herein report an efficiently asyinmetric synthesis of S-(+)-tylophorine (1), as a typically representative alkaloids.

Histidine as a catalyst in organic synthesis: A facile in situ synthesis ...

Indian Academy of Sciences (India)

Unknown

They are also used in the synthesis of many nitrogen-containing biologically ... addition to hydroxylamine, results in formation of an imine, azoxy compound 15, ... GC-MS, m/z: 211 (M+), 194 (base peak); 13C NMR (DMSO-d6) δ : 31⋅14 ...

Total Synthesis of Bryostatins. Development of Methodology for Atom-Economic and Stereoselective Synthesis of the C-ring Subunit

Science.gov (United States)

Trost, Barry M.; Frontier, Alison J.; Thiel, Oliver R.; Yang, Hanbiao; Dong, Guangbin

2012-01-01

Bryostatins, a family of structurally complicated macrolides, exhibit an exceptional range of biological activities. The limited availability and structural complexity of these molecules makes development of an efficient total synthesis particularly important. This article describes our initial efforts towards the total synthesis of bryostatins, in which chemoselective and atom-economical methods for stereoselective assembly of the C-ring subunit were developed. A Pd-catalyzed tandem alkyne-alkyne coupling/6-endo-dig cyclization sequence was explored and successfully pursued in the synthesis of a dihydropyran ring system. Elaboration of this methodology ultimately led to a concise synthesis of the C-ring subunit of bryostatins. PMID:21793057

Modulation of protein synthesis by polyamines.

Science.gov (United States)

Igarashi, Kazuei; Kashiwagi, Keiko

2015-03-01

Polyamines are ubiquitous small basic molecules that play important roles in cell growth and viability. Since polyamines mainly exist as a polyamine-RNA complex, we looked for proteins whose synthesis is preferentially stimulated by polyamines at the level of translation, and thus far identified 17 proteins in Escherichia coli and 6 proteins in eukaryotes. The mechanisms of polyamine stimulation of synthesis of these proteins were investigated. In addition, the role of eIF5A, containing hypusine formed from spermidine, on protein synthesis is described. These results clearly indicate that polyamines and eIF5A contribute to cell growth and viability through modulation of protein synthesis. © 2015 International Union of Biochemistry and Molecular Biology.

Chemical synthesis, characterization and evaluation of antimicrobial properties of Cu and its oxide nanoparticles

CSIR Research Space (South Africa)

Motlatle, Abesach M

2016-10-01

Full Text Available of Nanoparticle Research, vol. 18: DOI: 10.1007/s11051-016-3614-8 Chemical synthesis, characterization and evaluation of antimicrobial properties of Cu and its oxide nanoparticles Motlatle AM Kesevan Pillai S Scriba MR Ray SS ABSTRACT: Cu...

Total synthesis of (-)- and (+)-tedanalactam

Digital Repository Service at National Institute of Oceanography (India)

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

: The Journal of Organic Chemistry, vol.74(16); 6378-6381 1 Total Synthesis of (-) and (+)-Tedanalactam Mahesh S. Majik, † Peruninakulath S. Parameswaran, ‡ and Santosh G. Tilve* ,† Department of Chemistry, Goa University, Taleigao Plateau, Goa 403..., displaying a wide range of biological activities. 1 Piperidones are key synthetic intermediates 2 for the synthesis of piperidine ring due to the presence of keto function which allows the introduction of other groups. Piperidones are also known...

Design, Synthesis and Biological Evaluation of 2-(2-Amino-5(6-nitro-1H-benzimidazol-1-yl-N-arylacetamides as Antiprotozoal Agents

Directory of Open Access Journals (Sweden)

Emanuel Hernández-Núñez

2017-04-01

Full Text Available Parasitic diseases are a public health problem affecting millions of people worldwide. One of the scaffolds used in several drugs for the treatment of parasitic diseases is the benzimidazole moiety, a heterocyclic aromatic compound. This compound is a crucial pharmacophore group and is considered a privileged structure in medicinal chemistry. In this study, the benzimidazole core served as a model for the synthesis of a series of 2-(2-amino-5(6-nitro-1H-benzimidazol-1-yl-N-arylacetamides 1–8 as benznidazole analogues. The in silico pharmacological results calculated with PASS platform exhibited chemical structures highly similar to known antiprotozoal drugs. Compounds 1–8 when evaluated in silico for acute toxicity by oral dosing, were less toxic than benznidazole. The synthesis of compounds 1–8 were carried out through reaction of 5(6-nitro-1H-benzimidazol-2-amine (12 with 2-chlroactemides 10a–h, in the presence of K2CO3 and acetonitrile as solvent, showing an inseparable mixture of two regioisomers with the -NO2 group in position 5 or 6 with chemical yields of 60 to 94%. The prediction of the NMR spectra of molecule 1 coincided with the experimental chemical displacements of the regioisomers. Comparisons between the NMR prediction and the experimental data revealed that the regioisomer endo-1,6-NO2 predominated in the reaction. The in vitro antiparasitic activity of these compounds on intestinal unicellular parasites (Giardia intestinalis and Entamoeba histolytica and a urogenital tract parasite (Trichomonas vaginalis were tested. Compound 7 showed an IC50 of 3.95 μM and was 7 time more active against G. intestinalis than benznidazole. Compounds 7 and 8 showed 4 times more activity against T. vaginalis compared with benznidazole.

Synthesis, formulation of nucleo-equipment and biological studies of the {sup 99m} Tc-MAG{sub 3}; Sintesis, formulacion de nucleo-equipos y estudios biologicos de la {sup 99m} Tc-MAG{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Reyes H, L; Lezama C, J; Ferro F, G

1991-10-15

Technetium-99m-mercaptoacetyl glycylglycylglycine ({sup 99m}Tc-MAG{sub 3}) is introduced to replace o-iodohippurate (OIH) for renal function studies. In this paper we present the synthesis, labelling and biological evaluation of {sup 99m}Tc- MAG{sub 3} prepared in our laboratory. The precursor s-benzoyl-mercaptoacetyl glycyl glycylglycine (Bz-MAG{sub 3} ) was synthesized by condensation of glycylglycylglycine with chloroacetyl chloride to obtain chloroacetyl glycylglycylglycine and this product was condensate with sodium thiobenzoate. The Bz-MAG{sub 3} was characterized by IR and NMR. The labelling with {sup 99m}Tc was carried out at pH 9.0 using stannous chloride as a reducing agent with heating to boiling for 15 min. The benzoyl group is lost in this step, forming {sup 99m}Tc-MAG{sub 3} complex with radiochemical purity of 99%. The biodistribution properties were evaluated in mice and a rapid renal extraction was apparent at the 10 minutes value (51.65% of the injected dose). The radiotracer was administered to 5 patients showing a good biological behavior. Based on these results, the {sup 99m}Tc-MAG{sub 3} is expected to have widespread clinical utility in Mexico. (Author)

Extracellular synthesis of gold bionanoparticles by Nocardiopsis sp. and evaluation of its antimicrobial, antioxidant and cytotoxic activities.

Science.gov (United States)

Manivasagan, Panchanathan; Alam, Moch Syaiful; Kang, Kyong-Hwa; Kwak, Minseok; Kim, Se-Kwon

2015-06-01

Advancement of biological process for the synthesis of bionanoparticles is evolving into a key area of research in nanotechnology. The present study deals with the biosynthesis, characterization of gold bionanoparticles by Nocardiopsis sp. MBRC-48 and evaluation of their antimicrobial, antioxidant and cytotoxic activities. The gold bionanoparticles obtained were characterized by UV-visible spectroscopy, X-ray diffraction analysis, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray analysis and transmission electron microscopy (TEM). The synthesized gold bionanoparticles were spherical in shape with an average of 11.57 ± 1.24 nm as determined by TEM and dynamic light scattering (DLS) particle size analyzer, respectively. The biosynthesized gold nanoparticles exhibited good antimicrobial activity against pathogenic microorganisms. It showed strong antioxidant activity as well as cytotoxicity against HeLa cervical cancer cell line. The present study demonstrated the potential use of the marine actinobacterial strain of Nocardiopsis sp. MBRC-48 as an important source for gold nanoparticles with improved biomedical applications including antimicrobial, antioxidant as well as cytotoxic agent.

Understanding Protein Synthesis: An Interactive Card Game Discussion

Science.gov (United States)

Lewis, Alison; Peat, Mary; Franklin, Sue

2005-01-01

Protein synthesis is a complex process and students find it difficult to understand. This article describes an interactive discussion "game" used by first year biology students at the University of Sydney. The students, in small groups, use the game in which the processes of protein synthesis are actioned by the students during a…

76 FR 71045 - Center for Biologics Evaluation and Research Report of Scientific and Medical Literature and...

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2011-11-16

...] Center for Biologics Evaluation and Research Report of Scientific and Medical Literature and Information... period for the notice on its report of scientific and medical literature and information concerning the... ``Center for Biologics Evaluation and Research Report of Scientific and Medical Literature and Information...

Bis-spirochromanones as potent inhibitors of Mycobacterium tuberculosis: synthesis and biological evaluation.

Science.gov (United States)

Dongamanti, Ashok; Aamate, Vikas Kumar; Devulapally, Mohan Gandhi; Gundu, Srinivas; Balabadra, Saikrishna; Manga, Vijjulatha; Yogeeswari, Perumal; Sriram, Dharmarajan; Balasubramanian, Sridhar

2017-11-01

On the basis of reported antimycobacterial property of chroman-4-one pharmacophore, a series of chemically modified bis-spirochromanones were synthesized starting from 2-hydroxyacetophenone and 1,4-dioxaspiro[4.5] decan-8-one using a Kabbe condensation approach. The synthesized bis-spirochromanones were established based on their spectral data and X-ray crystal structure of 6e. All synthesized compounds were evaluated against Mycobacterium tuberculosis H37Rv (ATCC 27294) strain, finding that some products exhibited good antimycobacterial activity with minimum inhibitory concentration as low as [Formula: see text]. Docking studies were carried out to identify the binding interactions of compounds II, 6a and 6n with FtsZ. Compounds exhibiting good in vitro potency in the MTB MIC assay were further evaluated for toxicity using the HEK cell line.

Microwave Assisted Rapid and Green Synthesis of Silver Nanoparticles Using a Pigment Produced by Streptomyces coelicolor klmp33

OpenAIRE

Manikprabhu, Deene; Lingappa, K.

2013-01-01

Traditional synthesis of silver nanoparticles using chemical methods produces toxic substances. In contrast biological synthesis is regarded as a safe and nontoxic process but the major drawback of biological synthesis is, this process is slow. In the present investigation, we developed a rapid and green synthesis of silver nanoparticles employing a pigment produced by Streptomyces coelicolor klmp33 in just 90?s. The silver nanoparticles were characterized by UV-visible spectroscopy, transmis...

[Synthesis and degradation of hyaluronic acid by bacteria of Streptococcus genus].

Science.gov (United States)

Beloded, A V; Samoĭlenko, I I; Tsepilov, R N

2010-01-01

Modern data on metabolism of hyaluronic acid by bacteria from Streptococcus genus are presented. Several species of bacteria forming capsule from hyaluronic acid, which is analogous to glycosaminoglycan of vertebrates, are considered. Different aspects of hyaluronic acid synthesis are described: biochemical synthesis pathway, genetic basis, regulation of expression of genes belonging to hyaluronic acid synthesis operon. Biological role and physiologic importance of hyaluronic acid for bacteria, including its role in overcoming immune barrier by pathogenic species, are discussed. Process of depolymerization of hyaluronic acid in presence of hyaluronatlyases secreted by certain streptococci is considered. Characteristic of streptococcal enzyme hyaluronatlyase, its mechanism of catalytic effect, and biological function are presented.

75 FR 6401 - Medical Devices Regulated by the Center for Biologics Evaluation and Research; Availability of...

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2010-02-09

... Biologics Evaluation and Research (HFM-17), Food and Drug Administration, suite 200N, 1401 Rockville Pike... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2009-M-0513] Medical Devices Regulated by the Center for Biologics Evaluation and Research; Availability of Summaries...

Ernst Mayr and Evolutionary Biology

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 7. Polemics and Synthesis: Ernst Mayr and Evolutionary Biology. Renee M Borges. General Article Volume 10 Issue 7 July 2005 pp 21-33. Fulltext. Click here to view fulltext PDF. Permanent link:

[Synthetic biology and rearrangements of microbial genetic material].

Science.gov (United States)

Liang, Quan-Feng; Wang, Qian; Qi, Qing-Sheng

2011-10-01

As an emerging discipline, synthetic biology has shown great scientific values and application prospects. Although there have been many reviews of various aspects on synthetic biology over the last years, this article, for the first time, attempted to discuss the relationship and difference between microbial genetics and synthetic biology. We summarized the recent development of synthetic biology in rearranging microbial genetic materials, including synthesis, design and reduction of genetic materials, standardization of genetic parts and modularization of genetic circuits. The relationship between synthetic biology and microbial genetic engineering was also discussed in the paper.

Microwave-Assisted Synthesis of Phenylpropanoids and Coumarins: Total Synthesis of Osthol

Czech Academy of Sciences Publication Activity Database

Konrádová, Daniela; Kozubíková, H.; Doležal, Karel; Pospíšil, Jiří

2017-01-01

Roč. 2017, č. 35 (2017), s. 5204-5213 ISSN 1434-193X R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : Cyclization * Microwave chemistry * Oxygen heterocycles * Synthetic methods * Total synthesis Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Organic chemistry Impact factor: 2.834, year: 2016

Synthesis and Biological Evaluation of Novel Jatrorrhizine Derivatives with Amino Groups Linked at the 3-Position as Inhibitors of Acetylcholinesterase

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Xiaofei Jiang

2017-01-01

Full Text Available Jatrorrhizine was considered as one of the active constituents of Coptis chinensis Franch. Herein, jatrorrhizine derivatives with substituted amino groups linked at the 3-position were designed, synthesized, and biologically evaluated as inhibitors of acetylcholinesterase. Jatrorrhizine derivatives inhibited the activity of acetylcholinesterase (AChE to a greater extent than the lead compound jatrorrhizine. All these jatrorrhizine derivatives were proved to be potent inhibitors of acetylcholinesterase (AChE with submicromolar IC50 values, but less sensitive to butyrylcholinesterase (BuChE, which suggests that these jatrorrhizine derivatives are selective for AChE/BuChE. Compound 3g gave the most potent inhibitor activity for AChE (IC50 = 0.301 μM, which is greater than the lead compound jatrorrhizine. All these results demonstrated that these jatrorrhizine derivatives are potential inhibitors for AChE.

Design, Synthesis and Evaluation of Antiproliferative Activity of New Benzimidazolehydrazones

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Valentina Onnis

2016-04-01

Full Text Available The synthesis and antiproliferative activity of new benzimidazole derivatives bearing an hydrazone mojety at the 2-position is described. The new N′-(4-arylidene-1H-benzo[d]imidazole-2-carbohydrazides were evaluated for their cytostatic activity toward the murine leukemia (L1210, human T-cell leukemia (CEM, human cervix carcinoma (HeLa and human pancreas carcinoma cells (Mia Paca-2. A preliminary structure-activity relationship could be defined. Some of the compounds possess encouraging and consistent antiproliferative activity, having IC50 values in the low micromolar range.

Synthesis and biological evaluation of novel urea and thiourea derivatives of valacyclovir

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Katla Ramana Venkata

2014-01-01

Full Text Available A series of novel urea and thiourea derivatives of valacyclovir were efficiently synthesized in high yields and evaluated their antiviral activity. 2-((6-Amino-4-oxo-4,5-dihydro-1H-imidazo[4,5-c]pyridin-1-ylmethoxyethyl-2-amino-3-ethylbutanoate (valacyclovir 1 is reacted with various aromatic isocyanates/thiocyanates 2 in the presence of N, N- dimethyl piperazine as a base in THF: pyridine (4:1 to obtain valacyclovir urea/thiourea derivatives 3(a-j. The structures of the title compounds 3(a-j were confirmed by IR, NMR (1H, 13C, mass spectral and elemental analysis. The newly synthesized compounds were screened for their antiviral activity against Tobacco mosaic virus (TMV and antioxidant activity was evaluated by DPPH, SOD and GST methods. The title compounds exhibited potent antiviral and good antioxidant activities.

78 FR 20924 - Center for Biologics Evaluation and Research eSubmitter Pilot Evaluation Program for...

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2013-04-08

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Synthetic glycopeptides and glycoproteins with applications in biological research

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Ulrika Westerlind

2012-05-01

Full Text Available Over the past few years, synthetic methods for the preparation of complex glycopeptides have been drastically improved. The need for homogenous glycopeptides and glycoproteins with defined chemical structures to study diverse biological phenomena further enhances the development of methodologies. Selected recent advances in synthesis and applications, in which glycopeptides or glycoproteins serve as tools for biological studies, are reviewed. The importance of specific antibodies directed to the glycan part, as well as the peptide backbone has been realized during the development of synthetic glycopeptide-based anti-tumor vaccines. The fine-tuning of native chemical ligation (NCL, expressed protein ligation (EPL, and chemoenzymatic glycosylation techniques have all together enabled the synthesis of functional glycoproteins. The synthesis of structurally defined, complex glycopeptides or glyco-clusters presented on natural peptide backbones, or mimics thereof, offer further possibilities to study protein-binding events.

Synthesis and biological activity of the novel indanedione anticoagulant rodenticides containing fluorine

OpenAIRE

Chen, Feng; Liu, Liping; Bai, Zengguo; Zhang, Tianhua; Zhao, Keke

2016-01-01

Here, 3 fluorinated intermediates of drug were synthesized: (M1), (M2), (M3). Three new anticoagulant rodenticides were designed which were based on 4-hydroxycoumarin or 1,3-indandione, added acute toxicity groups containing fluorine. The structures of synthesized compounds were analyzed and proved by FT-IR spectroscopy and 1H nuclear magnetic resonance (1H-NMR). The compounds were also evaluated for their anticoagulant and acute biologic activity. In addition, both the acute orally toxicity ...

Synthesis, characterization, and biological activity of a new palladium(II) complex with deoxyalliin

Energy Technology Data Exchange (ETDEWEB)

Corbi, P.P.; Massabni, A.C. [Inst. de Quimica - UNESP, Dept., Dept. de Quimica Geral e Inoganica, Araraquara (Brazil)]. E-mail: pedrocorbi@yahoo.com; Moreira, A.G. [Inst. de Quimica - UNESP, Dept. de Quimica Geral e Inoganica, Araraquara (Brazil); Faculdade de Medicina de Ribeirao Preto - USP, Dept. de Bioquimica e Imunologia, Ribeirao Preto (Brazil); Medrano, F.J. [Laboratorio Nacional de Luz Sincrotron - LNLS, Campinas (Brazil); Jasiulionis, M.G. [Escola Paulista de Medicina - UNIFESP, Dept. de Micro-Imuno-Parasitologia, Sao Paulo (Brazil); Costa-Neto, C.M. [Faculdade de Medicina de Ribeirao Preto - USP, Dept. de Bioquimica e Imunologia, Ribeirao Preto (Brazil)

2005-02-15

Synthesis, characterization, and biological activity of a new water-soluble Pd(II)-deoxyalliin (S-allyl-L-cysteine) complex are described in this article. Elemental and thermal analysis for the complex are consistent with the formula [Pd(C{sub 6}H{sub 10}NO{sub 2}S){sub 2}]. {sup 13}C NMR, {sup 1}H NMR, and IR spectroscopy show coordination of the ligand to Pd(II) through S and N atoms in a square planar geometry. Final residue of the thermal treatment was identified as a mixture of PdO and metallic Pd. Antiproliferative assays using aqueous solutions of the complex against HeLa and TM5 tumor cells showed a pronounced activity of the complex even at low concentrations. After incubation for 24 h, the complex induced cytotoxic effect over HeLa cells when used at concentrations higher than 0.40 mmol/L. At lower concentrations, the complex was nontoxic, indicating its action is probably due to cell cycle arrest, rather than cell death. In agreement with these results, the flow cytometric analysis indicated that after incubation for 24 h at low concentrations of the complex cells are arrested in G0/G1. (author)

Functionalized polypyrrole film: synthesis, characterization, and potential applications in chemical and biological sensors.

Science.gov (United States)

Dong, Hua; Cao, Xiaodong; Li, Chang Ming

2009-07-01

In this paper, we report the synthesis of a carboxyl-functionalized polypyrrole derivative, a poly(pyrrole-N-propanoic acid) (PPPA) film, by electrochemical polymerization, and the investigation of its basic properties via traditional characterization techniques such as confocal-Raman, FTIR, SEM, AFM, UV-vis, fluorescence microscopy, and contact-angle measurements. The experimental data show that the as-prepared PPPA film exhibits a hydrophilic nanoporous structure, abundant -COOH functional groups in the polymer backbone, and high fluorescent emission under laser excitation. On the basis of these unique properties, further experiments were conducted to demonstrate three potential applications of the PPPA film in chemical and biological sensors: a permeable and permselective membrane, a membrane with specific recognition sites for biomolecule immobilization, and a fluorescent conjugated polymer for amplification of fluorescence quenching. Specifically, the permeability and permselectivity of ion species through the PPPA film are detected by means of rotating-disk-electrode voltammetry; the specific recognition sites on the film surface are confirmed with protein immobilization, and the amplification of fluorescence quenching is measured by the addition of a quenching agent with fluorescence microscopy. The results are in good agreement with our expectations.

An exploration on the synthesis and bio-applications of derivatives ...

African Journals Online (AJOL)

Keeping in view of the importance of this organic moiety in the field of medicine and biology here an attempt has been made to review the synthesis and biological importance of heterocyclic Mannich base derivatives. Keywords: Amines, β-amino carbonyl compounds, Biological activity, Heterocyclic Mannich base derivative ...

Synthesis and preliminary biological evaluation of new radioiodinated MMP inhibitors for imaging MMP activity in vivo

International Nuclear Information System (INIS)

Kopka, Klaus; Breyholz, Hans-Joerg; Wagner, Stefan; Law, Marilyn P.; Riemann, Burkhard; Schroeer, Sandra; Trub, Monika; Guilbert, Benedicte; Levkau, Bodo; Schober, Otmar; Schaefers, Michael

2004-01-01

Non-invasive measurement of matrix metalloproteinase (MMP) activity in vivo is a clinical challenge in many disease processes such as inflammation, tumor metastasis and atherosclerosis. Therefore, radioiodinated analogues of the non-peptidyl broad-spectrum MMP inhibitor (MMPI) CGS 27023A 1a were synthesized for non-invasive detection of MMP activity in vivo using single photon emission computed tomography (SPECT). The compounds Br-CGS 27023A 1b and HO-CGS 27023A 1d were synthesized from the amino acid D-valine and used as precursors for radioiodinated derivatives of CGS 27023A and their non-radioactive references I-CGS 27023A 1c and HO-I-CGS 27023A 1e. Radioiodination of the precursors with [ 123 I]NaI or [ 125 I]NaI produced the no-carrier-added MMP inhibitors [ 123 I]I-CGS 27023A 1f, [ 125 I]I-CGS 27023A 1g, HO-[ 123 I]I-CGS27023A 1h, and HO-[ 125 I]I-CGS 27023A 1i. In vitro studies showed that the non-radioactive analogues of the MMP inhibitors exhibited affinities against gelatinase A (MMP-2) and gelatinase B (MMP-9) in the nanomolar range, comparable to the parent compound CGS 27023A. In vivo biodistribution using HO-[ 125 I]I-CGS 27023A 1i in CL57 Bl6 mice showed rapid blood and plasma clearance and low retention in normal tissues. The preliminary biological evaluation warrant further studies of these radioiodinated MMP inhibitors as potential new radiotracers for imaging MMP activity in vivo

Cu(II AND Zn(II COMPLEX COMPOUNDS WITH BIGUANIDES AROMATIC DERIVATIVES. SYNTHESIS, CHARACTERIZATION, BIOLOGICAL ACTIVITY

Directory of Open Access Journals (Sweden)

Ticuţa Negreanu-Pîrjol

2011-05-01

Full Text Available In this paper we report the synthesis, physical-chemical characterization and antimicrobial activity of some new complex compounds of hetero-aromatic biguanides ligands, chlorhexidine base (CHX and chlorhexidine diacetate (CHXac2 with metallic ions Cu(II and Zn(II, in different molar ratio. The synthesized complexes were characterized by elemental chemical analysis and differential thermal analysis. The stereochemistry of the metallic ions was determined by infrared spectra, UV-Vis, EPR spectroscopy and magnetic susceptibility in the aim to establish the complexes structures. The biological activity of the new complex compounds was identified in solid technique by measuring minimum inhibition diameter of bacterial and fungal culture, against three standard pathogen strains, Escherichia coli ATCC 25922, Staphilococcus aureus ATCC 25923 and Candida albicans ATCC 10231. The results show an increased specific antimicrobial activity for the complexes chlorhexidine:Cu(II 1:1 and 1:2 compared with the one of the Zn(II complexes.

Using magnetic nanoparticles to manipulate biological objects

International Nuclear Information System (INIS)

Liu Yi; Gao Yu; Xu Chenjie

2013-01-01

The use of magnetic nanoparticles (MNPs) for the manipulation of biological objects, including proteins, genes, cellular organelles, bacteria, cells, and organs, are reviewed. MNPs are popular candidates for controlling and probing biological objects with a magnetic force. In the past decade, progress in the synthesis and surface engineering of MNPs has further enhanced this popularity. (topical review - magnetism, magnetic materials, and interdisciplinary research)

Engagement and Skill Development in Biology Students through Analysis of Art

Science.gov (United States)

Milkova, Liliana; Crossman, Colette; Wiles, Stephanie; Allen, Taylor

2013-01-01

An activity involving analysis of art in biology courses was designed with the goals of piquing undergraduates’ curiosity, broadening the ways in which college students meaningfully engage with course content and concepts, and developing aspects of students’ higher-level thinking skills, such as analysis, synthesis, and evaluation. To meet these learning outcomes, the activity had three key components: preparatory readings, firsthand visual analysis of art during a visit to an art museum, and communication of the analysis. Following a presentation on the methodology of visual analysis, students worked in small groups to examine through the disciplinary lens of biology a selection of approximately 12 original artworks related in some manner to love. The groups then developed and presented for class members a mini-exhibition of several pieces addressing one of two questions: 1) whether portrayals of love in art align with the growing understanding of the biology of love or 2) whether the bodily experience of love is universal or, alternatively, is culturally influenced, as is the experience of depression. Evaluation of quantitative and qualitative assessment data revealed that the assignment engaged students, supported development of higher-level thinking skills, and prompted meaningful engagement with course material. PMID:24297295

Engagement and skill development in biology students through analysis of art.

Science.gov (United States)

Milkova, Liliana; Crossman, Colette; Wiles, Stephanie; Allen, Taylor

2013-01-01

An activity involving analysis of art in biology courses was designed with the goals of piquing undergraduates' curiosity, broadening the ways in which college students meaningfully engage with course content and concepts, and developing aspects of students' higher-level thinking skills, such as analysis, synthesis, and evaluation. To meet these learning outcomes, the activity had three key components: preparatory readings, first-hand visual analysis of art during a visit to an art museum, and communication of the analysis. Following a presentation on the methodology of visual analysis, students worked in small groups to examine through the disciplinary lens of biology a selection of approximately 12 original artworks related in some manner to love. The groups then developed and presented for class members a mini-exhibition of several pieces addressing one of two questions: 1) whether portrayals of love in art align with the growing understanding of the biology of love or 2) whether the bodily experience of love is universal or, alternatively, is culturally influenced, as is the experience of depression. Evaluation of quantitative and qualitative assessment data revealed that the assignment engaged students, supported development of higher-level thinking skills, and prompted meaningful engagement with course material.

Redox Biology Course Evaluation Form | Center for Cancer Research

Science.gov (United States)

To improve the Redox Biology (RB) course in future years, we would appreciate your feedback by completing this course evaluation. Please score the course elements as poor, fair, average, good or excellent. Please type any comments that you have in response to the questions at the bottom of the form. Remember to include your name as you wish it to appear on the certificate.

Evaluation of biologic occupational risk control practices: quality indicators development and validation.

Science.gov (United States)

Takahashi, Renata Ferreira; Gryschek, Anna Luíza F P L; Izumi Nichiata, Lúcia Yasuko; Lacerda, Rúbia Aparecida; Ciosak, Suely Itsuko; Gir, Elucir; Padoveze, Maria Clara

2010-05-01

There is growing demand for the adoption of qualification systems for health care practices. This study is aimed at describing the development and validation of indicators for evaluation of biologic occupational risk control programs. The study involved 3 stages: (1) setting up a research team, (2) development of indicators, and (3) validation of the indicators by a team of specialists recruited to validate each attribute of the developed indicators. The content validation method was used for the validation, and a psychometric scale was developed for the specialists' assessment. A consensus technique was used, and every attribute that obtained a Content Validity Index of at least 0.75 was approved. Eight indicators were developed for the evaluation of the biologic occupational risk prevention program, with emphasis on accidents caused by sharp instruments and occupational tuberculosis prevention. The indicators included evaluation of the structure, process, and results at the prevention and biologic risk control levels. The majority of indicators achieved a favorable consensus regarding all validated attributes. The developed indicators were considered validated, and the method used for construction and validation proved to be effective. Copyright (c) 2010 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Enantioselective Total Synthesis of Antibiotic CJ-16,264, Synthesis and Biological Evaluation of Designed Analogues, and Discovery of Highly Potent and Simpler Antibacterial Agents.

Science.gov (United States)

Nicolaou, K C; Pulukuri, Kiran Kumar; Rigol, Stephan; Buchman, Marek; Shah, Akshay A; Cen, Nicholas; McCurry, Megan D; Beabout, Kathryn; Shamoo, Yousif

2017-11-08

An improved and enantioselective total synthesis of antibiotic CJ-16,264 through a practical kinetic resolution and an iodolactonization reaction to form the iodo pyrrolizidinone fragment of the molecule is described. A series of racemic and enantiopure analogues of CJ-16,264 was designed and synthesized through the developed synthetic technologies and tested against drug-resistant bacterial strains. These studies led to interesting structure-activity relationships and the identification of a number of simpler, and yet equipotent, or even more potent, antibacterial agents than the natural product, thereby setting the foundation for further investigations in the quest for new anti-infective drugs.

Societal Risk Evaluation Scheme (SRES: Scenario-Based Multi-Criteria Evaluation of Synthetic Biology Applications.

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Christopher L Cummings

Full Text Available Synthetic biology (SB applies engineering principles to biology for the construction of novel biological systems designed for useful purposes. From an oversight perspective, SB products come with significant uncertainty. Yet there is a need to anticipate and prepare for SB applications before deployment. This study develops a Societal Risk Evaluation Scheme (SRES in order to advance methods for anticipatory governance of emerging technologies such as SB. The SRES is based upon societal risk factors that were identified as important through a policy Delphi study. These factors range from those associated with traditional risk assessment, such as health and environmental consequences, to broader features of risk such as those associated with reversibility, manageability, anticipated levels of public concern, and uncertainty. A multi-disciplinary panel with diverse perspectives and affiliations assessed four case studies of SB using the SRES. Rankings of the SRES components are compared within and across the case studies. From these comparisons, we found levels of controllability and familiarity associated with the cases to be important for overall SRES rankings. From a theoretical standpoint, this study illustrates the applicability of the psychometric paradigm to evaluating SB cases. In addition, our paper describes how the SRES can be incorporated into anticipatory governance models as a screening tool to prioritize research, information collection, and dialogue in the face of the limited capacity of governance systems. To our knowledge, this is the first study to elicit data on specific cases of SB with the goal of developing theory and tools for risk governance.

Synthesis, biological evaluation and molecular modeling of 2-Hydroxyisoquinoline-1,3-dione analogues as inhibitors of HIV reverse transcriptase associated ribonuclease H and polymerase.

Science.gov (United States)

Tang, Jing; Vernekar, Sanjeev Kumar V; Chen, Yue-Lei; Miller, Lena; Huber, Andrew D; Myshakina, Nataliya; Sarafianos, Stefan G; Parniak, Michael A; Wang, Zhengqiang

2017-06-16

Human immunodeficiency virus (HIV) reverse transcriptase (RT) associated ribonuclease H (RNase H) remains the only virally encoded enzymatic function not clinically validated as an antiviral target. 2-Hydroxyisoquinoline-1,3-dione (HID) is known to confer active site directed inhibition of divalent metal-dependent enzymatic functions, such as HIV RNase H, integrase (IN) and hepatitis C virus (HCV) NS5B polymerase. We report herein the synthesis and biochemical evaluation of a few C-5, C-6 or C-7 substituted HID subtypes as HIV RNase H inhibitors. Our data indicate that while some of these subtypes inhibited both the RNase H and polymerase (pol) functions of RT, potent and selective RNase H inhibition was achieved with subtypes 8-9 as exemplified with compounds 8c and 9c. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Biocompatibility implications of polypyrrole synthesis techniques

International Nuclear Information System (INIS)

Fonner, John M; Nguyen, Hieu; Byrne, James D; Kou, Yann-Fuu; Syeda-Nawaz, Jeja; Schmidt, Christine E; Forciniti, Leandro

2008-01-01

Polypyrrole (PPy) is an inherently conducting polymer that has shown great promise for biomedical applications within the nervous system. However, to effectively use PPy as a biomaterial implant, it is important to understand and reproducibly control the electrical properties, physical topography and surface chemistry of the polymer. Although there is much research published on the use of PPy in various applications, there is no systematic study linking the methodologies used for PPy synthesis to PPy's basic polymeric properties (e.g., hydrophilicity, surface roughness), and to the biological effects these properties have on cells. Electrochemically synthesized PPy films differ greatly in their characteristics depending on synthesis parameters such as dopant, substrate and thickness, among other parameters. In these studies, we have used three dopants (chloride (Cl), tosylate (ToS), polystyrene sulfonate (PSS)), two substrates (gold and indium tin oxide-coated glass), and a range of thicknesses, to measure and compare the biomedically important characteristics of surface roughness, contact angle, conductivity, dopant stability and cell adhesion (using PC-12 cells and Schwann cells). As predicted, we discovered large differences in roughness depending on the dopant used and the thickness of the film, while substrate choice had little effect. From contact angle measurements, PSS was found to yield the most hydrophilic material, most likely because of free charges from the long PSS chains exposed on the surface of the PPy. ToS-doped PPy films were tenfold more conductive than Cl- or PSS-doped films. X-ray photoelectron spectroscopy studies were used to evaluate dopant concentrations of PPy films stored in water and phosphate buffered saline over 14 days, and conductance studies over the same timeframe measured electrical stability. PSS proved to be the most stable dopant, though all films experienced significant decay in conductivity and dopant concentration. Cell

Synthesis of technetium-99m labeled clinafloxacin (99mTc-CNN) complex and biological evaluation as a potential Staphylococcus aureus infection imaging agent

International Nuclear Information System (INIS)

Syed Qaiser Shah; Muhammad Rafiullah Khan

2011-01-01

In the present study synthesis of the 99m Tc-CNN complex and its efficacy as a prospective Staphylococcus aureus (S. aureus) infection imaging agent was assessed. The 99m Tc-CNN complex was characterized in terms of stability in saline, serum, in vitro binding with S. aureus and in vivo percent absorption in male Wister rats (MWR) infected with live and heat killed S. aureus. Radiochemically the 99m Tc-CNN complex showed stable behavior in saline and serum at different intervals. At 30 min after reconstitution the complex showed maximum radiochemical purity (RCP) yield of 97.55 ± 0.22%. The RCP yield decreased to 90.50 ± 0.18% within 240 min. In serum, 18.15% unwanted side product was appeared within 16 h of the incubation. In vitro saturated binding with S. aureus was observed at different intervals with a 62.00% maximum at 90 min. Normal percent in vivo uptake was observed in MWR artificially infected with live S. aureus with a five times higher in the infected muscle as compared to the inflamed and normal muscles. No difference in the percent uptake of the complex in MWR infected with heat killed S. aureus in the infected, inflamed and normal muscles were observed. Based on the promising in vitro and in vivo radiochemical and biological characteristics, we recommend the 99m Tc-CNN complex for in vivo localization of the S. aureus infectious foci. (author)

A method for evaluation of UV and biologically effective exposures to plants

International Nuclear Information System (INIS)

Paris, A.V.; Southern Queensland Univ., Toowoomba, QLD; Wong, J.C.F.; Galea, V.

1996-01-01

This paper presents a method for evaluating the UV and biologically effective exposures to a plant canopy during the irradiation of soybean with supplemental levels of UV radiation in a greenhouse study. The method employs four materials as dosimeters that allow evaluation of the UV spectra. The exposures evaluated at three growth stages were less by factors of 0.44, 0.49 and 0.56 compared to the ambient exposures. At the end of the irradiation period, the ambient biologically effective exposure for generalized plant response was higher by 180% compared to that calculated over the canopy. This is the magnitude of the error in UV studies that provide the ambient exposure as a measure of the UV incident on the plant. Additionally, the difference between the ambient and canopy exposures varied during the growth stages. These results indicate that the dosimetric technique applied to evaluating the UV exposures over a plant canopy is a more accurate representation of the UV exposure incidence on a plant than any obtained by measuring the ambient exposures only. (Author)

Strategy on biological evaluation for biodegradable/absorbable materials and medical devices.

Science.gov (United States)

Liu, Chenghu; Luo, Hongyu; Wan, Min; Hou, Li; Wang, Xin; Shi, Yanping

2018-01-01

During the last two decades, biodegradable/absorbable materials which have many benefits over conventional implants are being sought in clinical practices. However, to date, it still remains obscure for us to perform full physic-chemical characterization and biological risk assessment for these materials and related devices due to their complex design and coherent processing. In this review, based on the art of knowledge for biodegradable/absorbable materials and biological risk assessment, we demonstrated some promising strategies to establish and improve the current biological evaluation systems for these biodegradable/absorbable materials and related medical devices.

Synthesis, biological evaluation and structure-activity correlation study of a series of imidazol-based compounds as Candida albicans inhibitors.

Science.gov (United States)

Moraca, Francesca; De Vita, Daniela; Pandolfi, Fabiana; Di Santo, Roberto; Costi, Roberta; Cirilli, Roberto; D'Auria, Felicia Diodata; Panella, Simona; Palamara, Anna Teresa; Simonetti, Giovanna; Botta, Maurizio; Scipione, Luigi

2014-08-18

A new series of 2-(1H-imidazol-1-yl)-1-phenylethanol derivatives was synthesized. The antifungal activity was evaluated in vitro against different fungal species. The biological results show that the most active compounds possess an antifungal activity comparable or higher than Fluconazole against Candida albicans, non-albicans Candida species, Cryptococcus neoformans and dermathophytes. Because of their racemic nature, the most active compounds 5f and 6c were tested as pure enantiomers. For 6c the (R)-enantiomer resulted more active than the (S)-one, otherwise for 5f the (S)-enantiomer resulted the most active. To rationalize the experimental data, a ligand-based computational study was carried out; the results of the modelling study show that (S)-5f and (R)-6c perfectly align to the ligand-based model, showing the same relative configuration. Preliminary studies on the human lung adenocarcinoma epithelial cells (A549) have shown that 6c, 5e and 5f possess a low cytotoxicity. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Synthesis and biological evaluation of febrifugine analogues as potential antimalarial agents.

Science.gov (United States)

Zhu, Shuren; Zhang, Quan; Gudise, Chandrashekar; Wei, Lai; Smith, Erika; Zeng, Yuling

2009-07-01

Febrifugine is an alkaloid isolated from Dichroa febrifuga Lour as the active component against Plasmodium falciparum. Adverse side effects have precluded febrifugine as a potential clinical drug. In this study novel febrifugine analogues were designed and synthesized. Lower toxicity was achieved by reducing or eliminating the tendency of forming chemically reactive and toxic intermediates and metabolites. Synthesized compounds were evaluated for acute toxicity and in vitro and in vivo antimalarial efficacy. Some compounds are much less toxic than the natural product febrifugine and existing antimalarial drug chloroquine and are expected to possess wide therapeutic windows. These compounds, as well as the underlying design rationale, may find usefulness in the discovery and development of new antimalarial drugs.

Redox Biology Course Evaluation Form | Center for Cancer Research

Science.gov (United States)

To improve the Redox Biology (RB) course in future years, we would appreciate your feedback by completing this course evaluation. Please score the course elements as poor, fair, average, good or excellent. Please type any comments that you have in response to the questions at the bottom of the form. Remember to include your name as you wish it to appear on the certificate. Thank you for your feedback.

Biological evaluation of transdichloridoplatinum(II) complexes with 3- and 4-acetylpyridine in comparison to cisplatin

International Nuclear Information System (INIS)

Filipovic, Lana; Arandelovic, Sandra; Gligorijevic, Nevenka; Krivokuca, Ana; Jankovic, Radmila; Srdic-Rajic, Tatjana; Rakic, Gordana; Tesic, Zivoslav; Radulovic, Sinisa

2013-01-01

In our previous study we reported the synthesis and cytotoxicity of two trans-platinum(II) complexes: trans-[PtCl 2 (3-acetylpyridine) 2 ] (1) and trans-[PtCl 2 (4-acetylpyridine) 2 ] (2), revealing significant cytotoxic potential of 2. In order to evaluate the mechanism underlying biological activity of both trans-Pt(II) isomers, comparative studies versus cisplatin were performed in HeLa, MRC-5 and MS1 cells. The cytotoxic activity of the investigated complexes was determined using SRB assay. The colagenolytic activity was determined using gelatin zymography, while the effect of platinum complexes on matrix metalloproteinases 2 and 9 mRNA expression was evaluated by quantitative real-time PCR. Apoptotic potential and cell cycle alterations were determined by FACS analyses. Western blot analysis was used to evaluate the effect on expression of DNA-repair enzyme ERCC1, and quantitative real-time PCR was used for the ERCC1 mRNA expression analysis. In vitro antiangiogenic potential was determined by tube formation assay. Platinum content in intracellular DNA and proteins was determined by inductively coupled plasma-optical emission spectrometry. Compound 2 displayed an apparent cytoselective profile, and flow cytometry analysis in HeLa cells indicated that 2 exerted antiproliferative effect through apoptosis induction, while 1 induced both apoptosis and necrosis. Action of 1 and 2, as analyzed by quantitative real-time PCR and Western blot, was associated with down-regulation of ERCC1. Both trans-complexes inhibited MMP-9 mRNA expression in HeLa, while 2 significantly abrogated in vitro tubulogenesis in MS1 cells. The ability of 2 to induce multiple and selective in vitro cytotoxic effects encourages further investigations of trans-platinum(II) complexes with substituted pyridines

Approaches to chemical synthetic biology.

Science.gov (United States)

Chiarabelli, Cristiano; Stano, Pasquale; Anella, Fabrizio; Carrara, Paolo; Luisi, Pier Luigi

2012-07-16

Synthetic biology is first represented in terms of two complementary aspects, the bio-engineering one, based on the genetic manipulation of extant microbial forms in order to obtain forms of life which do not exist in nature; and the chemical synthetic biology, an approach mostly based on chemical manipulation for the laboratory synthesis of biological structures that do not exist in nature. The paper is mostly devoted to shortly review chemical synthetic biology projects currently carried out in our laboratory. In particular, we describe: the minimal cell project, then the "Never Born Proteins" and lastly the Never Born RNAs. We describe and critically analyze the main results, emphasizing the possible relevance of chemical synthetic biology for the progress in basic science and biotechnology. Copyright © 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Preliminary synthesis of pollination biology in the Cape flora

CSIR Research Space (South Africa)

Rebelo, AG

1987-01-01

Full Text Available biology are covered. Chapters reviewing plant breeding systems, insect, bird, mammal and wind pollination, and gene flow are introduced by a perspective on the role of the fossil record in pollination biology. A speculative chapter on the constraints...

Surface active monomers synthesis, properties, and application

CERN Document Server

Borzenkov, Mykola

2014-01-01

This brief includes information on the background?of and development of synthesis of various types of surface active monomers. The authors explain the importance of utilization of surface active monomers for creation of surface active polymers? and the various biomedical applications of such compounds . This brief introduces techniques for the synthesis of novel types of surface active monomers, their colloidal and polymerizable properties and application for needs of medicine and biology.

Short synthesis and antimalarial activity of fagaronine

OpenAIRE

Rivaud, M.; Mendoza, A.; Sauvain, Michel; Valentin, A.; Jullian, Valérie

2012-01-01

Herein, we report a new synthesis of fagaronine 1, inspired by the synthesis reported by Luo for nornitidine. The in vitro biological activity of fagaronine against malaria on several chloroquine-sensitive and resistant Plasmodium falciparum strains was confirmed, and the selectivity index compared to mammalian cells was calculated. Fagaronine was found to have very good antimalarial activity in vivo, comparable to the activity of the reference compound chloroquine. Therefore, fagaronine appe...

Synthesis and preliminary biological evaluation of new radioiodinated MMP inhibitors for imaging MMP activity in vivo

Energy Technology Data Exchange (ETDEWEB)

Kopka, Klaus E-mail: kopka@uni-muenster.de; Breyholz, Hans-Joerg; Wagner, Stefan; Law, Marilyn P.; Riemann, Burkhard; Schroeer, Sandra; Trub, Monika; Guilbert, Benedicte; Levkau, Bodo; Schober, Otmar; Schaefers, Michael

2004-02-01

Non-invasive measurement of matrix metalloproteinase (MMP) activity in vivo is a clinical challenge in many disease processes such as inflammation, tumor metastasis and atherosclerosis. Therefore, radioiodinated analogues of the non-peptidyl broad-spectrum MMP inhibitor (MMPI) CGS 27023A 1a were synthesized for non-invasive detection of MMP activity in vivo using single photon emission computed tomography (SPECT). The compounds Br-CGS 27023A 1b and HO-CGS 27023A 1d were synthesized from the amino acid D-valine and used as precursors for radioiodinated derivatives of CGS 27023A and their non-radioactive references I-CGS 27023A 1c and HO-I-CGS 27023A 1e. Radioiodination of the precursors with [{sup 123}I]NaI or [{sup 125}I]NaI produced the no-carrier-added MMP inhibitors [{sup 123}I]I-CGS 27023A 1f, [{sup 125}I]I-CGS 27023A 1g, HO-[{sup 123}I]I-CGS27023A 1h, and HO-[{sup 125}I]I-CGS 27023A 1i. In vitro studies showed that the non-radioactive analogues of the MMP inhibitors exhibited affinities against gelatinase A (MMP-2) and gelatinase B (MMP-9) in the nanomolar range, comparable to the parent compound CGS 27023A. In vivo biodistribution using HO-[{sup 125}I]I-CGS 27023A 1i in CL57 Bl6 mice showed rapid blood and plasma clearance and low retention in normal tissues. The preliminary biological evaluation warrant further studies of these radioiodinated MMP inhibitors as potential new radiotracers for imaging MMP activity in vivo.

Chemistry and biology by new multiple choice

International Nuclear Information System (INIS)

Seo, Hyeong Seok; Kim, Seong Hwan

2003-02-01

This book is divided into two parts, the first part is about chemistry, which deals with science of material, atom structure and periodic law, chemical combination and power between molecule, state of material and solution, chemical reaction and an organic compound. The second part give description of biology with molecule and cell, energy in cells and chemical synthesis, molecular biology and heredity, function on animal, function on plant and evolution and ecology. This book has explanation of chemistry and biology with new multiple choice.

Rational design, synthesis, and pharmacological evaluation of 2-azanorbornane-3-exo,5-endo-dicarboxylic acid

DEFF Research Database (Denmark)

Bunch, Lennart; Liljefors, Tommy; Greenwood, Jeremy R

2003-01-01

conformationally restricted (S)-glutamic acid (Glu) analogue intended as a mimic of the folded Glu conformation. The synthesis of 1 was completed in its racemic form in eight steps from commercially available starting materials. As a key step, the first facially selective hydroboration of a 5-methylidene[2......The design and synthesis of conformationally restricted analogues of alpha-amino acids is an often used strategy in medicinal chemistry research. Here we present the rational design, synthesis, and pharmacological evaluation of 2-azanorbornane-3-exo,5-endo-dicarboxylic acid (1), a novel...... studies on native 2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid (AMPA) (IC(50) > 300 microM, [(3)H]AMPA) or kainic acid (IC(50) > 160 microM, [(3)H]kainic acid) receptors nor in binding studies on the cloned iGluR5,6 subtypes (IC(50) > 300 microM, [(3)H]kainic acid)....

Evaluation of the biological and scanning distribution of hydroxyapatite-153Sm radiotherapeutic agent

International Nuclear Information System (INIS)

Herrera, J.; Paredes, N.; Portilla, A.; Miranda, J.; Carrillo, D.

1999-01-01

Fixation of 153 Sm labeled hydroxyapatite (HA) in the synovial capsule and extra articular localization were evaluated by means of biological distribution tests and gamma scanning studies. These were carried out using HA- 153 Sm with particle size ranging between 5 and μm, and radiochemical purity above 99%. Animal models used were wistar rats and new zealand rabbits. Rabbits were injected with 7,4 MBq of HA- 153 Sm while rats received between 1,85 and 92,6 MBq of HA- 153 Sm. In both cases injection was given in the intra articular area. After injection, scanning images were obtained in rabbits on the 1 st , 3 rd and 7 st day and in rats on the 2 nd and 7 th day. Biological distribution studies are conducted in the 2 hours to 9 days range in rats and one the 7 th day in rabbits. No extra articular localization of HA- 153 Sm was found in scanning conducted on rabbits by the 1 st , 3 rd and 7 st day after injection, neither on rats by the 2 nd and 7 th day. Biological distributions for rabbits and rats show localization above 99% in the intra articular area, during the evaluated periods of time. The evaluations of the biological distribution and the scintigraphic images show that fixation of HA- 153 Sm in the synovial capsule up to the 9 th day is very high

Synthesis, biological evaluation, and baboon PET imaging of the potential adrenal imaging agent cholesteryl-p-[18f]fluorobenzoate

International Nuclear Information System (INIS)

Jonson, Stephanie D.; Welch, Michael J.

1999-01-01

Cholesteryl-p-[ 18 F]fluorobenzoate ([ 18 F]CFB) was investigated as a potential adrenal positron emission tomography (PET) imaging agent for the diagnostic imaging of adrenal disorders. We describe the synthesis, biodistribution, adrenal autoradiography, and baboon PET imaging of [ 18 F]CFB. The synthesis of [ 18 F]CFB was facilitated by the use of a specially designed microwave cavity that was instrumental in effecting 70-83% incorporation of fluorine-18 in 60 s via [ 18 F]fluoro-for-nitro exchange. Tissue distribution studies in mature female Sprague-Dawley rats showed good accumulation of [ 18 F]CFB in the steroid-secreting tissues, adrenals and ovaries, at 1 h postinjection. The effectiveness of [ 18 F]CFB to accumulate in diseased adrenals was shown through biodistribution studies in hypolipidemic rats, which showed a greater than threefold increase in adrenal uptake at 1 h and increased adrenal/liver and adrenal/kidney ratios. Analysis of the metabolites at 1 h in the blood, adrenals, spleen, and ovaries of hypolipidemic and control rats showed the intact tracer representing greater than 86%, 93%, 92%, and 82% of the accumulated activity, respectively. [ 18 F]CFB was confirmed to selectively accumulate in the adrenal cortex versus the adrenal medulla by autoradiography. Normal baboon PET imaging with [ 18 F]CFB effectively showed adrenal localization as early as 15 min after injection of the tracer, with enhanced adrenal contrast seen at 60-70 min. These results suggest that [ 18 F]CFB may be useful as an adrenal PET imaging agent for assessing adrenal disorders

Synthesis, characterization and biological evaluation of a novel "3 + 1" mixed ligand 99mTc complex having an aliphatic thiol as coligand.

Science.gov (United States)

Rey, A; Papadopoulos, M; Leon, E; Mallo, L; Pirmettis, Y; Manta, E; Raptopoulou, C; Chiotellis, E; Leon, A

2001-03-01

A novel "3 + 1" mixed ligand 99mTc complex with N,N-bis(2-mercaptoethyl)-N'N'-diethyl-ethilenediamine as ligand and 1-octanethiol as coligand was prepared and evaluated as potential brain radiopharmaceutical. Preparation at tracer level was accomplished by substitution, using 99mTc-glucoheptonate as precursor and a coligand/ligand ratio of 5. Under these conditions the labeling yield was over 80% and a major product with radiochemical purity >80% was isolated by HPLC methods and used for biological evaluation. Chemical characterization at carrier level was developed using the corresponding rhenium and 99gTc complexes. Results were consistent with the expected "3 + 1" structure and X-ray diffraction study demonstrated that the complex adopted a distorted trigonal bipyramidal geometry. All sulphur atoms underwent ionization leading to the formation of a neutral compound. Biodistribution in mice demonstrated early brain uptake, fast blood clearance and excretion through hepatobiliary system. Although brain/blood ratio increased significantly with time, this novel 99mTc complex did not exhibit ideal properties as brain perfusion radiopharmaceutical since brain uptake was too low.

Synthesis, characterization and biological evaluation of a novel ''3+1'' mixed ligand 99mTc complex having an aliphatic thiol as coligand

International Nuclear Information System (INIS)

Rey, A.; Papadopoulos, M.; Leon, E.; Mallo, L.; Pirmettis, Y.; Manta, E.; Raptopoulou, C.; Chiotellis, E.; Leon, A.

2001-01-01

A novel ''3+1'' mixed ligand 99m Tc complex with N,N-bis(2-mercaptoethyl)-N'N'-diethyl-ethilenediamine as ligand and 1-octanethiol as coligand was prepared and evaluated as potential brain radiopharmaceutical. Preparation at tracer level was accomplished by substitution, using 99m Tc-glucoheptonate as precursor and a coligand/ligand ratio of 5. Under these conditions the labeling yield was over 80% and a major product with radiochemical purity >80% was isolated by HPLC methods and used for biological evaluation. Chemical characterization at carrier level was developed using the corresponding rhenium and 99g Tc complexes. Results were consistent with the expected ''3+1'' structure and X-ray diffraction study demonstrated that the complex adopted a distorted trigonal bipyramidal geometry. All sulphur atoms underwent ionization leading to the formation of a neutral compound. Biodistribution in mice demonstrated early brain uptake, fast blood clearance and excretion through hepatobiliary system. Although brain/blood ratio increased significantly with time, this novel 99m Tc complex did not exhibit ideal properties as brain perfusion radiopharmaceutical since brain uptake was too low

Evaluation of a commercial biologically based IMRT treatment planning system

International Nuclear Information System (INIS)

Semenenko, Vladimir A.; Reitz, Bodo; Day, Ellen; Qi, X. Sharon; Miften, Moyed; Li, X. Allen

2008-01-01

A new inverse treatment planning system (TPS) for external beam radiation therapy with high energy photons is commercially available that utilizes both dose-volume-based cost functions and a selection of cost functions which are based on biological models. The purpose of this work is to evaluate quality of intensity-modulated radiation therapy (IMRT) plans resulting from the use of biological cost functions in comparison to plans designed using a traditional TPS employing dose-volume-based optimization. Treatment planning was performed independently at two institutions. For six cancer patients, including head and neck (one case from each institution), prostate, brain, liver, and rectal cases, segmental multileaf collimator IMRT plans were designed using biological cost functions and compared with clinically used dose-based plans for the same patients. Dose-volume histograms and dosimetric indices, such as minimum, maximum, and mean dose, were extracted and compared between the two types of treatment plans. Comparisons of the generalized equivalent uniform dose (EUD), a previously proposed plan quality index (fEUD), target conformity and heterogeneity indices, and the number of segments and monitor units were also performed. The most prominent feature of the biologically based plans was better sparing of organs at risk (OARs). When all plans from both institutions were combined, the biologically based plans resulted in smaller EUD values for 26 out of 33 OARs by an average of 5.6 Gy (range 0.24 to 15 Gy). Owing to more efficient beam segmentation and leaf sequencing tools implemented in the biologically based TPS compared to the dose-based TPS, an estimated treatment delivery time was shorter in most (five out of six) cases with some plans showing up to 50% reduction. The biologically based plans were generally characterized by a smaller conformity index, but greater heterogeneity index compared to the dose-based plans. Overall, compared to plans based on dose

Evaluation of an automated double-synthesis module: efficiency and reliability of subsequent radiosyntheses of FHBG and FLT

International Nuclear Information System (INIS)

Niedermoser, Sabrina; Pape, Manuela; Gildehaus, Franz Josef; Wängler, Carmen; Hartenbach, Markus; Schirrmacher, Ralf; Bartenstein, Peter; Wängler, Björn

2012-01-01

We optimized the synthesis methods for 3′-deoxy-3′-[ 18 F]fluorothymidine ([ 18 F]FLT) and 9-(4-[ 18 F]fluoro-3-[hydroxymethyl]butyl)guanine) ([ 18 F]FHBG) and automated them on an Explora General Nucleophilic double-synthesis module. Furthermore, the synthesis efficiency and reliability and the formation of cross-contaminations of the products when preparing two consecutive batches were evaluated. Whereas the preinstalled FLT synthesis conditions required substantial modification in reaction and neutralization conditions to achieve radiochemical yields of up to 60% within 70±10 min including high-performance liquid chromatography purification, the synthesis of FHBG had to be implemented to the module to obtain competitive radiochemical yields of up to 40% in an overall synthesis time of 60±10 min. The radiochemical purities obtained were ≥99% and ≥96% for the synthesis of [ 18 F]FLT and [ 18 F]FHBG, respectively. No significant changes in yield or purity could be observed between both batch productions. We found that the yields and purities also did not change when performing FLT after FHBG syntheses and vice versa. Hence, we developed a synthesis setup that offers the opportunity to perform two subsequent syntheses of either [ 18 F]FLT, [ 18 F]FHBG or [ 18 F]FLT after [ 18 F]FHBG without decrease in radiochemical yields and purities. Also, no cross-contaminations were observed, which can be attributed to the use of separate product delivery tubes, purification columns and an automated intermediate cleaning program. These results open up the possibility of producing consecutively either two equal 18 F-fluorinated tracers or two different ones in high yields on the same synthesis module.

Total synthesis of bryostatins: the development of methodology for the atom-economic and stereoselective synthesis of the ring C subunit.

Science.gov (United States)

Trost, Barry M; Frontier, Alison J; Thiel, Oliver R; Yang, Hanbiao; Dong, Guangbin

2011-08-22

Bryostatins, a family of structurally complicated macrolides, exhibit an exceptional range of biological activities. The limited availability and structural complexity of these molecules makes development of an efficient total synthesis particularly important. This article describes our initial efforts towards the total synthesis of bryostatins, in which chemoselective and atom-economical methods for the stereoselective assembly of the ring C subunit were developed. A Pd-catalyzed tandem alkyne-alkyne coupling/6-endo-dig cyclization sequence was explored and successfully pursued in the synthesis of a dihydropyran ring system. Elaboration of this methodology ultimately led to a concise synthesis of the ring C subunit of bryostatins. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Salicylic acid derivatives: synthesis, features and usage as therapeutic tools.

Science.gov (United States)

Ekinci, Deniz; Sentürk, Murat; Küfrevioğlu, Ömer İrfan

2011-12-01

In the field of medicinal chemistry, there is a growing interest in the use of small molecules. Although acetyl salicylic acid is well known for medical applications, little is known about other salicylic acid derivatives, and there is serious lack of data and information on the effects and biological evaluation that connect them. This review covers the synthesis and drug potencies of salicylic acid derivatives. After a brief overview of the information on salicylic acid and its features, a detailed review of salicylic acids as drugs and prodrugs, usage as cyclooxygenase inhibitors, properties in plants, synthesis and recent patents, is developed. Salicylic acid research is still an important area and innovations continue to arise, which offer hope for new therapeutics in related fields. It is anticipated that this review will guide the direction of long-term drug/nutraceutical safety trials and stimulate ideas for future research.

Synthesis and biological activity evaluation of hydrazone derivatives based on a Tröger's base skeleton

Czech Academy of Sciences Publication Activity Database

Kaplánek, R.; Havlík, M.; Dolenský, B.; Rak, J.; Džubák, P.; Konečný, P.; Hajdúch, M.; Králová, Jarmila; Král, V.

2015-01-01

Roč. 23, č. 7 (2015), s. 1651-1659 ISSN 0968-0896 R&D Projects: GA ČR(CZ) GAP303/11/1291 Grant - others:GA MŠk(CZ) EE2.3.30.0060; GA MŠk(CZ) LO1304 Program:EE; LD Institutional support: RVO:68378050 Keywords : Anticancer agents * Cancer treatment * Complexation studies * Hydrazone * Troger's base Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.923, year: 2015

Multistep continuous-flow synthesis in medicinal chemistry: discovery and preliminary structure-activity relationships of CCR8 ligands.

Science.gov (United States)

Petersen, Trine P; Mirsharghi, Sahar; Rummel, Pia C; Thiele, Stefanie; Rosenkilde, Mette M; Ritzén, Andreas; Ulven, Trond

2013-07-08

A three-step continuous-flow synthesis system and its application to the assembly of a new series of chemokine receptor ligands directly from commercial building blocks is reported. No scavenger columns or solvent switches are necessary to recover the desired test compounds, which were obtained in overall yields of 49-94%. The system is modular and flexible, and the individual steps of the sequence can be interchanged with similar outcome, extending the scope of the chemistry. Biological evaluation confirmed activity on the chemokine CCR8 receptor and provided initial structure-activity-relationship (SAR) information for this new ligand series, with the most potent member displaying full agonist activity with single-digit nanomolar potency. To the best of our knowledge, this represents the first published example of efficient use of multistep flow synthesis combined with biological testing and SAR studies in medicinal chemistry. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Detecting and evaluating communities in complex human and biological networks

Science.gov (United States)

Morrison, Greg; Mahadevan, L.

2012-02-01

We develop a simple method for detecting the community structure in a network can by utilizing a measure of closeness between nodes. This approach readily leads to a method of coarse graining the network, which allows the detection of the natural hierarchy (or hierarchies) of community structure without appealing to an unknown resolution parameter. The closeness measure can also be used to evaluate the robustness of an individual node's assignment to its community (rather than evaluating only the quality of the global structure). Each of these methods in community detection and evaluation are illustrated using a variety of real world networks of either biological or sociological importance and illustrate the power and flexibility of the approach.

Automatic compilation from high-level biologically-oriented programming language to genetic regulatory networks.

Science.gov (United States)

Beal, Jacob; Lu, Ting; Weiss, Ron

2011-01-01

The field of synthetic biology promises to revolutionize our ability to engineer biological systems, providing important benefits for a variety of applications. Recent advances in DNA synthesis and automated DNA assembly technologies suggest that it is now possible to construct synthetic systems of significant complexity. However, while a variety of novel genetic devices and small engineered gene networks have been successfully demonstrated, the regulatory complexity of synthetic systems that have been reported recently has somewhat plateaued due to a variety of factors, including the complexity of biology itself and the lag in our ability to design and optimize sophisticated biological circuitry. To address the gap between DNA synthesis and circuit design capabilities, we present a platform that enables synthetic biologists to express desired behavior using a convenient high-level biologically-oriented programming language, Proto. The high level specification is compiled, using a regulatory motif based mechanism, to a gene network, optimized, and then converted to a computational simulation for numerical verification. Through several example programs we illustrate the automated process of biological system design with our platform, and show that our compiler optimizations can yield significant reductions in the number of genes (~ 50%) and latency of the optimized engineered gene networks. Our platform provides a convenient and accessible tool for the automated design of sophisticated synthetic biological systems, bridging an important gap between DNA synthesis and circuit design capabilities. Our platform is user-friendly and features biologically relevant compiler optimizations, providing an important foundation for the development of sophisticated biological systems.

Contemporary issues in evolutionary biology

Indian Academy of Sciences (India)

We are delighted to bring to the readers, a set of peer-reviewed papers on evolutionary biology, published as a special issue of the Journal of Genetics. These papers emanated from ruminations upon and discussions at the Foundations of. Evolutionary Theory: the Ongoing Synthesis meeting at Coorg, India, in February ...

Synthesis, toxicity, biocompatibility, and biomedical applications of graphene and graphene-related materials

Directory of Open Access Journals (Sweden)

Gurunathan S

2016-05-01

Full Text Available Sangiliyandi Gurunathan, Jin-Hoi Kim Stem Cell and Regenerative Biology, Konkuk University, Seoul, Republic of Korea Abstract: Graphene is a two-dimensional atomic crystal, and since its development it has been applied in many novel ways in both research and industry. Graphene possesses unique properties, and it has been used in many applications including sensors, batteries, fuel cells, supercapacitors, transistors, components of high-strength machinery, and display screens in mobile devices. In the past decade, the biomedical applications of graphene have attracted much interest. Graphene has been reported to have antibacterial, antiplatelet, and anticancer activities. Several salient features of graphene make it a potential candidate for biological and biomedical applications. The synthesis, toxicity, biocompatibility, and biomedical applications of graphene are fundamental issues that require thorough investigation in any kind of applications related to human welfare. Therefore, this review addresses the various methods available for the synthesis of graphene, with special reference to biological synthesis, and highlights the biological applications of graphene with a focus on cancer therapy, drug delivery, bio-imaging, and tissue engineering, together with a brief discussion of the challenges and future perspectives of graphene. We hope to provide a comprehensive review of the latest progress in research on graphene, from synthesis to applications. Keywords: biomedical applications, cancer therapy, drug delivery, graphene, graphene-related materials, tissue engineering, toxicity 

Synthesis, physical-chemical and biological properties of 1,8-disubstituted compounds of theobromine. III. 8-Amino-p-chlorobenzyltheobromines

Directory of Open Access Journals (Sweden)

D. G. Ivanchenko

2014-08-01

Full Text Available Introduction. This work is a follow-up to a series of research activities dedicated to the search of biologically active compounds among the xanthine derivatives. Aim of the Work.Development of simple laboratory-based methods for 8-amino-1-p-chlorobenzyltheobromines synthesis and the study of antioxidant, antimicrobial and antifungal effect of the synthesized compounds. Materials and Methods of Research.The melting point has been determined with the help of an open capillary method with TAP device (M. Elemental analysis has been performed with the helpof the instrument ElementarVario L cube, NMR-spectra have been taken on a spectrometer Bruker SF-400 (operating frequency of 400 MHz, solvent DMSO-d6 or DMSO-d6 + CDCl3, internal standard – TMS. These data correspond to thecalculated elemental analysis. The synthesis of 8-aminosubstituted 1-p-chlorobenzyltheobromine (2,3.Mixture 0.01 mole of8-bromo-1-p-chlorobenzyltheobromine (1, 0.03 mole of pyrrolidine (2 or piperidine (3, 40 ml of cellosolve is boiled during 4 hours, then it is allowed to steam out dry in a vacuum. Dry residue is processed with water, then residual matter which has been formed is filtered out, washed with water and recrystallized from the aqueous ethanol. The synthesis of 8-amino-1-p-chlorobenzyltheobromines (4-7. Mixture 0.01 mole of initial compound (1, 0.03 mole of the respective amine and 40 ml of cellosolve is boiled during 4 hours, thenit is allowed to cool down and is diluted with water. After this, residual matter which has been formed is filtered out, washed with water and aqueous propanol-2 and recrystallized from the water ethanol. Molecular descriptors have been calculated using the computer programs ALOGPS and DRAGON, whereas biological properties of the synthesized compounds have been calculated with the help of GUSAR and ACD / Percepta Platform. Antioxidant activity (AOA has been studied in vitro applying the method of nonenzymic initiation of free

Carbon dots: Synthesis from renewable sources via hydrothermal carbonization, characterization and evaluation of their interaction with biological systems

International Nuclear Information System (INIS)

Moraes, Liz Specian de; Alves, Oswaldo Luiz

2016-01-01

Full text: Carbon dots (CDs) constitute a new class of carbon-based nanomaterials with interesting photoluminescent properties that enable their potential use in bioimaging, sensing and drug delivery applications. They consist of quasi spherical nanoparticles with size below 10 nm. As a consequence of their low toxicity and biocompatibility, CDs have been considered as a promising alternative to traditional semiconductor-based quantum dots. In addition, they can be synthesized from accessible renewable sources in an environmentally friendly perspective. In this work, we report the use of bovine serum albumin (BSA) and bovine plasma (BP) as precursors to synthesis of CDs applying hydrothermal carbonization method. The study also includes the physical chemical characterization and the evaluation of interaction between these nanomaterials and biosystems, using hemolytic assay. The morphology and size of the carbon nanoparticles were analyzed by Transmission Electronic Microscopy. CDs obtained from BSA (BSA-CDs) and BP (BP-CDs) had spherical shape with an average size of 5.6 and 3.7 nm, respectively. The fluorescence quantum yield was calculated using quinine sulfate as reference. BSA-CDs and BP-CDs exhibited quantum yields of 4.9% and 4.0%, when they were excited at wavelength of 315 and 300 nm, respectively. Furthermore, the red-shift phenomenon was observed in the emission spectra of both synthesized CDs, indicating the formation of particles with different sizes or the presence of surface energy traps distribution. The composition of CDs was determined by Elemental Analysis and X-ray Photoelectron Spectroscopy. Both nanomaterials contained C, N, O and S elements. The hemolytic assay demonstrated the synthesized CDs did not cause damage to red blood cell membrane at concentrations between 5 and 250 μg mL -1 . (author)

Carbon dots: Synthesis from renewable sources via hydrothermal carbonization, characterization and evaluation of their interaction with biological systems

Energy Technology Data Exchange (ETDEWEB)

Moraes, Liz Specian de; Alves, Oswaldo Luiz, E-mail: liz.specian@hotmail.com.br [Universidade Estadual de Campinas (UNICAMP), SP (Brazil)

2016-07-01

Full text: Carbon dots (CDs) constitute a new class of carbon-based nanomaterials with interesting photoluminescent properties that enable their potential use in bioimaging, sensing and drug delivery applications. They consist of quasi spherical nanoparticles with size below 10 nm. As a consequence of their low toxicity and biocompatibility, CDs have been considered as a promising alternative to traditional semiconductor-based quantum dots. In addition, they can be synthesized from accessible renewable sources in an environmentally friendly perspective. In this work, we report the use of bovine serum albumin (BSA) and bovine plasma (BP) as precursors to synthesis of CDs applying hydrothermal carbonization method. The study also includes the physical chemical characterization and the evaluation of interaction between these nanomaterials and biosystems, using hemolytic assay. The morphology and size of the carbon nanoparticles were analyzed by Transmission Electronic Microscopy. CDs obtained from BSA (BSA-CDs) and BP (BP-CDs) had spherical shape with an average size of 5.6 and 3.7 nm, respectively. The fluorescence quantum yield was calculated using quinine sulfate as reference. BSA-CDs and BP-CDs exhibited quantum yields of 4.9% and 4.0%, when they were excited at wavelength of 315 and 300 nm, respectively. Furthermore, the red-shift phenomenon was observed in the emission spectra of both synthesized CDs, indicating the formation of particles with different sizes or the presence of surface energy traps distribution. The composition of CDs was determined by Elemental Analysis and X-ray Photoelectron Spectroscopy. Both nanomaterials contained C, N, O and S elements. The hemolytic assay demonstrated the synthesized CDs did not cause damage to red blood cell membrane at concentrations between 5 and 250 μg mL{sup -1}. (author)

Synthesis, characterization and biological evaluation of novel diesters of 4,4'-dihydroxy azoxy benzene with long chain carboxylic acid

International Nuclear Information System (INIS)

Shehzadi, S.; Siddiqi, H.M.; Qasim, M.M.

2014-01-01

Synthesis of novel symmetrical azoxy diesters have been prepared by the reaction of 4,4'-dihydroxyazoxy benzene with aliphatic acid halides of varying chain lengths. The synthesized compounds have been characterized by spectral and analytical means. These symmetrical azoxy diesters exhibit good antifungal against six fungal strains (Mucor species, Aspergillus niger, Aspergillus flavus, Alternaria solani, Fusarium solani and Aspergillus fumigatus) and antitumor activities while no significant antibacterial activity has been observed. These synthesized compounds are also potent free radical scavengers. (author)

Fungal Anticancer Metabolites: Synthesis Towards Drug Discovery.

Science.gov (United States)

Barbero, Margherita; Artuso, Emma; Prandi, Cristina

2018-01-01

Fungi are a well-known and valuable source of compounds of therapeutic relevance, in particular of novel anticancer compounds. Although seldom obtainable through isolation from the natural source, the total organic synthesis still remains one of the most efficient alternatives to resupply them. Furthermore, natural product total synthesis is a valuable tool not only for discovery of new complex biologically active compounds but also for the development of innovative methodologies in enantioselective organic synthesis. We undertook an in-depth literature searching by using chemical bibliographic databases (SciFinder, Reaxys) in order to have a comprehensive insight into the wide research field. The literature has been then screened, refining the obtained results by subject terms focused on both biological activity and innovative synthetic procedures. The literature on fungal metabolites has been recently reviewed and these publications have been used as a base from which we consider the synthetic feasibility of the most promising compounds, in terms of anticancer properties and drug development. In this paper, compounds are classified according to their chemical structure. This review summarizes the anticancer potential of fungal metabolites, highlighting the role of total synthesis outlining the feasibility of innovative synthetic procedures that facilitate the development of fungal metabolites into drugs that may become a real future perspective. To our knowledge, this review is the first effort to deal with the total synthesis of these active fungi metabolites and demonstrates that total chemical synthesis is a fruitful means of yielding fungal derivatives as aided by recent technological and innovative advancements. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Synthesis and properties of ZnFe2O4 replica with biological hierarchical structure

International Nuclear Information System (INIS)

Liu, Hongyan; Guo, Yiping; Zhang, Yangyang; Wu, Fen; Liu, Yun; Zhang, Di

2013-01-01

Highlights: • ZFO replica with hierarchical structure was synthesized from butterfly wings. • Biotemplate has a significant impact on the properties of ZFO material. • Our method opens up new avenues for the synthesis of spinel ferrites. -- Abstract: ZnFe 2 O 4 replica with biological hierarchical structure was synthesized from Papilio paris by a sol–gel method followed by calcination. The crystallographic structure and morphology of the obtained samples were characterized by X-ray diffraction, field-emission scanning electron microscope, and transmittance electron microscope. The results showed that the hierarchical structures were retained in the ZFO replica of spinel structure. The magnetic behavior of such novel products was measured by a vibrating sample magnetometer. A superparamagnetism-like behavior was observed due to nanostructuration size effects. In addition, the ZFO replica with “quasi-honeycomb-like structure” showed a much higher specific capacitance of 279.4 F g −1 at 10 mV s −1 in comparison with ZFO powder of 137.3 F g −1 , attributing to the significantly increased surface area. These results demonstrated that ZFO replica is a promising candidate for novel magnetic devices and supercapacitors

Synthesis of pterostilbene by Julie Olefination

Science.gov (United States)

A simple, stereoselective route for the synthesis of the biologically active compounds trans-pterostilbene and tetramethoxy stilbene from the readily available starting materials 3,5-dimethoxy benzyl alcohol and 4-hydroxy benzaldehyde was developed using Julia olefination as a key reaction....

Facile Synthesis of Oleanolic Acid Monoglycosides and Diglycosides

Directory of Open Access Journals (Sweden)

Mao-Sheng Cheng

2008-07-01

Full Text Available Oleanolic acid and its glycosides are important natural products, possessing various attractive biological activities such as antitumor, antivirus and anti-inflammatory properties. In the present work, fifteen oleanolic acid saponins bearing various saccharide moieties, including 3-monoglycoside, 28-monoglycoside and 3,28-diglycoside, were easily synthesized in high yields. Benzyl was chosen as the protective group for the COOH(28 group, instead of commonly used methyl and allyl, to avoid difficulties in the final deprotection. Alkali-promoted condensation of the carboxylic acid with bromoglycosides was found to be more efficient in the synthesis of 28-glycosides. Two approaches were investigated and proved practicable in the preparation of 3,28- diglycosides. This method is suitable for preparing oleanolic acid glycosides with structural diversity for extensive biological evaluation and structure-activity relationship study, and it also apply new idea for the corresponding synthetic methods to the glycoside derivatives of other triterpenoid.

Evaluating efficacy of an environmental policy to prevent biological invasions.

Science.gov (United States)

Bailey, Sarah A; Deneau, Matthew G; Jean, Laurent; Wiley, Chris J; Leung, Brian; MacIsaac, Hugh J

2011-04-01

Enactment of any environmental policy should be followed by an evaluation of its efficacy to ensure optimal utilization of limited resources, yet measuring the success of these policies can be a challenging task owing to a dearth of data and confounding factors. We examine the efficacy of ballast water policies enacted to prevent biological invasions in the Laurentian Great Lakes. We utilize four criteria to assess the efficacy of this environmental regulation: (1) Is the prescribed management action demonstrably effective? (2) Is the management action effective under operational conditions? (3) Can compliance be achieved on a broad scale? (4) Are desired changes observed in the environment? The four lines of evidence resulting from this analysis indicate that the Great Lakes ballast water management program provides robust, but not complete, protection against ship-mediated biological invasions. Our analysis also indicates that corresponding inspection and enforcement efforts should be undertaken to ensure that environmental policies translate into increased environmental protection. Similar programs could be implemented immediately around the world to protect the biodiversity of the many freshwater ecosystems which receive ballast water discharges by international vessels. This general framework can be extended to evaluate efficacy of other environmental policies.

Synthesis and biological evaluation of new pyrazolo[3,4-d]pyrimidine derivatives

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Asma Agrebi

2014-05-01

Full Text Available Several new pyrazolopyrimidine compounds were achieved from aminocyanopyarazole 1. The starting material 1 was initially coupled with orthoester at refluxed with various primary amines, ammonia, hydrazines and hydroxylamine to furnish a series of pyrazolo[3,4-d]pyrimidines. The reaction of imidate 2a-b with hydrazide derivatives led to the formation of pyrazolo[3,4-d][1,2,4]triazolo[4,3-c]pyrimidines. Some of the synthesized compounds 3a and 4c were evaluated for their anti-inflammatory, antipyretic and nociceptive activities. We start by studing the toxicity of these two molecules by measuring the corresponding DL50. The DL50 of 3a and 4c are estimated to 1333.2mg / kg and 1593.5mg / kg respectively. Pharmacological evaluation showed that compounds 3a and 4c at doses (5.5-22.2 mg / Kg, i.p exhibited anti-inflammatory activities compared to Ibuprofen (150 mg / Kg, i.p, used as a refer ence drug. Further, our study showed that the injection of derived pyrazolopyrimidines on hyperthermic animal leads to a decrease in temperature after 1 hours of treatment compared to paracetamol used as reference. In addition, the injection of derived pyrazolopyrimidines at different doses contains a potent nociceptive activity. This effect is dose-dependent compared to aspirin.

Synthesis and biological evaluation of radioiodinated N-2-(4-piperidyl)ethyl benzamides

International Nuclear Information System (INIS)

Efange, S.M.N.; Michelson, R.H.; Boudreau, R.J.; Thomas, J.R.; Knusel, B.; Hefti, F.; Tennison, J.R.

1993-01-01

Three iodinated benzamides, 5-7, analogues of the potent acetylcholinesterase inhibitor 1-benzyl-4-[N-[4'-(benzylsulfonyl) benzoyl-N-methylamino]ethyl]piperidine (2), were synthesized and evaluated as potential anticholinesterase agents. All three compounds were found to be three orders of magnitude less potent than the parent compound. However, receptor screening revealed that compounds 5-7 exhibit nanomolar affinity for the sigma binding site. Both [ 125 I]5 and [ 125 I]7 were synthesized and evaluated in rats. Following the intravenous administration of [ 125 I]5 into rats, 1.59% of the injected dose was found in the rat brain within 5 min. The level of radioactivity in the brain remained steady for 2 h, the duration of the study. In contrast, 0.42% of the injected dose was detected in the rat brain following the i.v. injection of [ 125 I]7. Coadministration of either [ 125 I]5 or [ 125 I]7 with 0.5 μmol/kg of haloperidol resulted in a 56-73% reduction in the level of radioactivity in the rat brain, suggesting that these compounds bind to the sigma binding site in vivo. Planar imaging studies with [ 123 I]5 revealed significant accumulation of radioactivity within the monkey brain, with a half-life of 6 h. Compound [ 123 I]5 may be potentially useful for studying sigma receptor distribution in the human brain. (author)

Synthesis and biological evaluation of radioiodinated N-2-(4-piperidyl)ethyl benzamides

International Nuclear Information System (INIS)

Efange, S.M.N.; Michelson, R.H.; Boudreau, R.J.; Thomas, J.R.; Knusel, B.; Hefti, F.; Tennison, J.R.

1993-01-01

Three iodinated benzamides, 5-7, analogues of the potent acetylcholinesterase inhibitor 1-benzyl-4[N-[4'-(benzylsulfonyl) benzoyl-N-methylamino]ethyl]piperidine were synthesized and evaluated as potential anticholinesterase agents. All three compounds were found to be three orders of magnitude less potent than the parent compound. However, receptor screening revealed that compounds 5-7 exhibit nanomolar affinity for the sigma binding site. Both [ 125 I]5 and [ 125 I]7 were synthesized and evaluated in rats. Following the intravenous administration of [ 125 I]5 into rats, 1.59% of the injected dose was found in the rat brain within 5 min. The level of radioactivity in the brain remained steady for 2 h, the duration of the study. In contrast, 0.42% of the injected dose was detected in the rat brain following the i.v. injection of [ 125 I]7. Coadministration of either [ 125 I]5 or [ 125 I]7 with 0.5 μmol/kg of haloperidol resulted in a 56-73% reduction in the level of radioactivity in the rat brain, suggesting that these compounds bind to the sigma binding site in vivo. Planar imaging studies with [ 123 I]5 revealed significant accumulation of radioactivity within the monkey brain, with a half-life of 6 h. Compound [ 123 I]5 may be potentially useful for studying sigma receptor distribution in the human brain. (Author)

The central dogma of cell biology.

Science.gov (United States)

Cooper, S

1981-06-01

The Continuum Model proposes that preparations for DNA synthesis occur continuously during all phases of the division cycle. Various stimuli activate cell proliferation by changing the rate of initiator (protein) synthesis. Cell division does not initiate any process regulating cell proliferation. Cell division is the end of a process and the beginning of nothing. The alternative model which has cell proliferation regulated in the G1 phase of the division cycle is reexamined and the two types of evidence for this model, G1-variability and G1-arrest are shown to be compatible with the Continuum Model. Here, the Continuum Model is generalized to produce a new look at the logic of the division cycle in prokaryotes and eukaryotes. This new view, the Central Dogma of Cell Biology, is presented and two predictions are made. I propose that (i) cell division does not have any regulatory function, and (ii) that DNA synthesis may, indeed, have some affect on the synthesis of initiator.

Synthesis of ferrocenestrone: the first metallocene based steroid analogue

Czech Academy of Sciences Publication Activity Database

Hessler, F.; Císařová, I.; Sedlák, David; Bartůněk, Petr; Kotora, Martin

2012-01-01

Roč. 18, č. 18 (2012), s. 5515-5518 ISSN 0947-6539 R&D Projects: GA MŠk(CZ) 1M0508; GA ČR GA204/09/1905; GA MŠk(CZ) LC06077 Institutional support: RVO:68378050 ; RVO:61388963 Keywords : asymmetric synthesis * ferrocenestrones * metallocenes * steroids * synthesis design Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.831, year: 2012

An investigation of in vivo wound healing activity of biologically synthesized silver nanoparticles

Science.gov (United States)

Kaler, Abhishek; Mittal, Amit Kumar; Katariya, Mahesh; Harde, Harshad; Agrawal, Ashish Kumar; Jain, Sanyog; Banerjee, Uttam Chand

2014-09-01

Therapeutic use of nano-silver is claimed to have reduced side effects and enhanced curative activity as compared to its ionic counterpart (silver ions). The present work aims to screen microbes for the synthesis of silver nanoparticles (AgNPs), to formulate the nano-silver-based Carbopol gel and evaluating its wound healing efficacy on rat model. The goal was to develop the topical formulation based on bio-nano-silver to control the infection and healing the wounds with higher efficacy. Procedure involved the use of Saccharomyces boulardii for the synthesis of silver nanoparticles in the size range of 3-10 nm and these nanoparticles were used for the preparation of Carbopol-based nano-silver gel. Highly stable Carbopol nanogel was developed with good rheological properties. The burn wound healing potential of this nano-silver gel was evaluated on SD rats via visual observation, transepidermal water loss and histology of skin. Excellent wound healing was observed with AgNPs. Biologically synthesized AgNPs-based nano-silver gel showed superior wound healing efficacy as compared to marketed formulations and silver ions.

Synthesis and Biological Evaluation of a New Acyclic Pyrimidine Derivative as a Probe for Imaging Herpes Simplex Virus Type 1 Thymidine Kinase Gene Expression

Directory of Open Access Journals (Sweden)

Simon M. Ametamey

2013-07-01

Full Text Available With the idea of finding a more selective radiotracer for imaging herpes simplex virus type 1 thymidine kinase (HSV1-tk gene expression by means of positron emission tomography (PET, a novel [18F]fluorine radiolabeled pyrimidine with 4-hydroxy-3-(hydroxymethylbutyl side chain at N-1 (HHB-5-[18F]FEP was prepared and evaluated as a potential PET probe. Unlabeled reference compound, HHB-5-FEP, was synthesized via a five-step reaction sequence starting from 5-(2-acetoxyethyl-4-methoxypyrimidin-2-one. The radiosynthesis of HHB-[18F]-FEP was accomplished by nucleophilic radiofluorination of a tosylate precursor using [18F]fluoride-cryptate complex in 45% ± 4 (n = 4 radiochemical yields and high purity (>99%. The biological evaluation indicated the feasibility of using HHB-5-[18F]FEP as a PET radiotracer for monitoring HSV1-tk expression in vivo.

NEW DERIVATIVES OF 2-R1-N-(5-R-1,3,4-THIADIAZOL-2-YL-BENZOLSULFONAMIDES: SYNTHESIS, PHYSICOCHEMICAL PROPERTIES AND BIOLOGICAL ACTIVITY PREDICTION

Directory of Open Access Journals (Sweden)

Sych I.V.

2015-12-01

Full Text Available Introduction: The analysis of modern literature, including overseas one, showed that a lot of the scientific researches is devoted to finding and creating biologically active compounds on base 1,3,4-thiadiazole. Derivatives of 1,3,4-thiadiazole are the large group of heterocyclic compounds with high rates of antimicrobial, antituberculosis, antidiabetic, antineoplastic and anticonvulsant activity. Material and methods: The purpose of this study was the expansion of sulfone derivatives substituted nitrogen-containing heterocyclic systems through the synthesis of 2-R1-N (5-R-1,3,4-thiadiazol-2-ilbenzolsulfonamides and prediction their pharmacological activity for future planning pharmacological screening. Synthesis of semi-products 2-amino-5-R-1,3,4-thiadiazoles was carried out by cyclization thiosemicarbazide and substituted derivatives of carboxylic acids in the presence of concentrated sulfuric acid. The synthesis of target compounds 2-R1-N(5-R-1,3,4-thiadiazol-2-ylbenzolsulfon-amides was carried out by N-acylation of 2-amino-5R-1,3,4-thiadiazole substituted benzolsul-fochlorides in the presence of anhydrous pyridine. The reaction proceeds by the classic SN2-mechanism. The resulting compounds are white crystalline substances, soluble in alcohol, chloroform and acetone, difficult to dissolve in water. Yields of obtained compounds was satisfactory (76-84%. The purity of the obtained compounds was determined by TLC. The structure of the obtained compounds was proved by elemental analysis, IR methods and 1H NMR spectroscopy. NMR 1H spectra were recorded at Bruker WM spectrometer (200 MHz; solvent DMSO-d6; chemical shifts were in ppm, internal standard (TMS (tetramethylsilane was used. The prognosis of biological activity for obtained compounds were carried out using the program PASS (Prediction of Activity Spectra for Substances in order to plan the further pharmacological screening. The program PASS predicts more than 500 kinds of biological

Synthesis and Biological Evaluation of Novel Thiosemicarbazone ...

African Journals Online (AJOL)

NICO

referred to as 'covalent biotherapy', and thus possesses a dual mode of action, namely heme alkylation with the trioxane entity, and heme stacking and inhibition of ... through hydrogen bonding and dipole interactions.15 They are the main structural features of a number of antifungal drugs. (e.g. fluconazole, isavuconazole ...

Synthesis and biological evaluation of a 99mTc-labelled cyclic RGD peptide for imaging the αvβ3 expression

International Nuclear Information System (INIS)

Haubner, F.; Bock, M.; Schwaiger, M.; Wester, H.J.; Bruchertseifer, F.; Kessler, H.

2004-01-01

Aim: The αvβ3 integrin is involved in tumour induced angiogenesis and tumour metastasis. We describe the synthesis and evaluation of a 99m Tc-labelled RGD analogue for the visualisation of αvβ3 integrin expression. Methods: The linear peptides were assembled on a solid support. Cyclisation was performed under high dilution conditions. For conjugation with the chelator peptide, a water soluble carbodiimide was used. Radiolabelling was carried out due to standard procedures with high radiochemical yield and radiochemical purity. For in vivo evaluation, nude mice bearing αvβ3-positive human melanoma M21 and αv-negative human melanoma M21-L or Balb / c mice bearing αv-positive murine osteosarcoma were used. Results: Activity accumulation of 99m Tc-DKCK-RGD 240 min p.i. was 1.1% ID/g in the αvβ3-positive melanoma and 0.3% ID/g in the negative control tumour. In the osteosarcoma model 2.2% ID/g was found 240 min p.i. Planar gamma camera images allowed contrasting visualisation of αvβ3-positive tumours 240 min p.i. Blocking of the tumour using the αvβ3-selective pentapeptide cyclo(-Arg-Gly-Asp-D-Phe-Val-) reduces activity accumulation in the tumour to background level. However, 240 min p.i. highest activity concentration was found in kidneys resulting in low tumour / kidney ratios. Metabolite analysis 240 min p.i. showed approximately 60% intact tracer in kidneys and 80% in the tumour. Only 24% intact tracer was found in blood 30 min p.i. Conclusion: 99m Tc-DKCK-RGD allows imaging of αvβ3-positive tumours in mice. However, pharmacokinetics as well as metabolic stability of the tracer have to be improved for potential clinical application. (orig.)

[Update on the biology of heme synthesis in erythroid cells].

Science.gov (United States)

Fujiwara, Tohru; Harigae, Hideo

2015-02-01

Heme is a prosthetic group of hemoproteins playing important roles in oxygen transport, detoxification, circadian rhythm, microRNA processing, regulation of transcription, and translation. The majority of heme (-85%) is synthesized in red blood cells mainly for hemoglobin production, whereas hepatocytes account for most of the rest, functioning primarily in the synthesis of cytochrome P450 enzymes and mitochondrial respiratory enzymes. Thus, failure of heme biosynthesis causes severe inherited or acquired disorders in humans, including porphyria and sideroblastic anemia. The heme biosynthetic pathway is composed of eight enzymes that work in either mitochondria or the cytoplasm, which have been extensively researched and frequently reviewed. On the other hand, the mechanisms governing transport and intracellular trafficking of heme intermediates, as well as their potential links to human diseases, are poorly understood. Herein, we focus on recent understanding of the heme biosynthetic pathway and on human disorders due to defective heme synthesis in erythroid cells, such as X-linked sideroblastic anemia and erythropoietic protoporphyria.

Ni-Cr based dental alloys; Ni release, corrosion and biological evaluation

Energy Technology Data Exchange (ETDEWEB)

Reclaru, L., E-mail: lucien.reclaru@pxgroup.com [PX Holding S.A., Dep R and D Corrosion and Biocompatibility Group, Bd. des Eplatures 42, CH-2304 La Chaux-de-Fonds (Switzerland); Unger, R.E.; Kirkpatrick, C.J. [Institute for Pathology, REPAIR Lab, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstr.1, D-55101 Mainz (Germany); Susz, C.; Eschler, P.-Y.; Zuercher, M.-H. [PX Holding S.A., Dep R and D Corrosion and Biocompatibility Group, Bd. des Eplatures 42, CH-2304 La Chaux-de-Fonds (Switzerland); Antoniac, I. [Materials Science and Engineering Faculty, Politehnica of Bucharest, 060042 Bucharest (Romania); Luethy, H. [Institute of Dental Materials Science and Technology, University of Basel, Hebelstrasse 3, CH-4056 Basel (Switzerland)

2012-08-01

In the last years the dental alloy market has undergone dramatic changes for reasons of economy and biocompatibility. Nickel based alloys have become widely used substitute for the much more expensive precious metal alloys. In Europe the prevalence of nickel allergy is 10-15% for female adults and 1-3% for male adults. Despite the restrictions imposed by the EU for the protection of the general population in contact dermatitis, the use of Ni-Cr dental alloys is on the increase. Some questions have to be faced regarding the safety risk of nickel contained in dental alloys. We have collected based on many EU markets, 8 Ni-Cr dental alloys. Microstructure characterization, corrosion resistance (generalized, crevice and pitting) in saliva and the quantities of cations released in particular nickel and CrVI have been evaluated. We have applied non parametric classification tests (Kendall rank correlation) for all chemical results. Also cytotoxicity tests and an evaluation specific to TNF-alpha have been conducted. According to the obtained results, it was found that their behavior to corrosion was weak but that nickel release was high. The quantities of nickel released are higher than the limits imposed in the EU concerning contact with the skin or piercing. Surprisingly the biological tests did not show any cytotoxic effect on Hela and L929 cells or any change in TNF-alpha expression in monocytic cells. The alloys did not show any proinflammatory response in endothelial cells as demonstrated by the absence of ICAM-1 induction. We note therefore that there is really no direct relationship between the in vitro biological evaluation tests and the physico-chemical characterization of these dental alloys. Clinical and epidemiological studies are required to clarify these aspects. - Highlights: Black-Right-Pointing-Pointer Nickel released was higher than the limits imposed in EU in contact with the skin. Black-Right-Pointing-Pointer No direct relationship between the

Drawing melodies: evaluation of chironomic singing synthesis.

Science.gov (United States)

d'Alessandro, Christophe; Feugère, Lionel; Le Beux, Sylvain; Perrotin, Olivier; Rilliard, Albert

2014-06-01

Cantor Digitalis, a real-time formant synthesizer controlled by a graphic tablet and a stylus, is used for assessment of melodic precision and accuracy in singing synthesis. Melodic accuracy and precision are measured in three experiments for groups of 20 and 28 subjects. The task of the subjects is to sing musical intervals and short melodies, at various tempi, using chironomy (hand-controlled singing), mute chironomy (without audio feedback), and their own voices. The results show the high accuracy and precision obtained by all the subjects for chironomic control of singing synthesis. Some subjects performed significantly better in chironomic singing compared to natural singing, although other subjects showed comparable proficiency. For the chironomic condition, mean note accuracy is less than 12 cents and mean interval accuracy is less than 25 cents for all the subjects. Comparing chironomy and mute chironomy shows that the skills used for writing and drawing are used for chironomic singing, but that the audio feedback helps in interval accuracy. Analysis of blind chironomy (without visual reference) indicates that a visual feedback helps greatly in both note and interval accuracy and precision. This study demonstrates the capabilities of chironomy as a precise and accurate mean for controlling singing synthesis.

Synthesis and biological evaluation of radioiodinated N-2-(4-piperidyl)ethyl benzamides

Energy Technology Data Exchange (ETDEWEB)

Efange, S M.N.; Michelson, R H; Boudreau, R J; Thomas, J R [Minnesota Univ., Minneapolis, MN (United States); Knusel, B; Hefti, F [Minnesota Univ., Minneapolis, MN (United States). Hospitals; Tennison, J R [University of Southern Cailfornia, Los Angeles, CA (United States). Andrus Gerontology Center

1993-05-01

Three iodinated benzamides, 5-7, analogues of the potent acetylcholinesterase inhibitor 1-benzyl-4-[N-[4'-(benzylsulfonyl) benzoyl-N-methylamino]ethyl]piperidine (2), were synthesized and evaluated as potential anticholinesterase agents. All three compounds were found to be three orders of magnitude less potent than the parent compound. However, receptor screening revealed that compounds 5-7 exhibit nanomolar affinity for the sigma binding site. Both [[sup 125]I]5 and [[sup 125]I]7 were synthesized and evaluated in rats. Following the intravenous administration of [[sup 125]I]5 into rats, 1.59% of the injected dose was found in the rat brain within 5 min. The level of radioactivity in the brain remained steady for 2 h, the duration of the study. In contrast, 0.42% of the injected dose was detected in the rat brain following the i.v. injection of [[sup 125]I]7. Coadministration of either [[sup 125]I]5 or [[sup 125]I]7 with 0.5 [mu]mol/kg of haloperidol resulted in a 56-73% reduction in the level of radioactivity in the rat brain, suggesting that these compounds bind to the sigma binding site in vivo. Planar imaging studies with [[sup 123]I]5 revealed significant accumulation of radioactivity within the monkey brain, with a half-life of 6 h. Compound [[sup 123]I]5 may be potentially useful for studying sigma receptor distribution in the human brain. (author).

Synthesis and biological evaluation of radioiodinated N-2-(4-piperidyl)ethyl benzamides

Energy Technology Data Exchange (ETDEWEB)

Efange, S.M.N.; Michelson, R.H.; Boudreau, R.J.; Thomas, J.R. (Minnesota Univ., Minneapolis, MN (United States)); Knusel, B.; Hefti, F. (Minnesota Univ., Minneapolis, MN (United States). Hospitals); Tennison, J.R. (University of Southern Cailfornia, Los Angeles, CA (United States). Andrus Gerontology Center)

1993-05-01

Three iodinated benzamides, 5-7, analogues of the potent acetylcholinesterase inhibitor 1-benzyl-4-[N-[4'-(benzylsulfonyl) benzoyl-N-methylamino]ethyl]piperidine (2), were synthesized and evaluated as potential anticholinesterase agents. All three compounds were found to be three orders of magnitude less potent than the parent compound. However, receptor screening revealed that compounds 5-7 exhibit nanomolar affinity for the sigma binding site. Both [[sup 125]I]5 and [[sup 125]I]7 were synthesized and evaluated in rats. Following the intravenous administration of [[sup 125]I]5 into rats, 1.59% of the injected dose was found in the rat brain within 5 min. The level of radioactivity in the brain remained steady for 2 h, the duration of the study. In contrast, 0.42% of the injected dose was detected in the rat brain following the i.v. injection of [[sup 125]I]7. Coadministration of either [[sup 125]I]5 or [[sup 125]I]7 with 0.5 [mu]mol/kg of haloperidol resulted in a 56-73% reduction in the level of radioactivity in the rat brain, suggesting that these compounds bind to the sigma binding site in vivo. Planar imaging studies with [[sup 123]I]5 revealed significant accumulation of radioactivity within the monkey brain, with a half-life of 6 h. Compound [[sup 123]I]5 may be potentially useful for studying sigma receptor distribution in the human brain. (author).

PLANT ISOFLAVONES: BIOSYNHTESIS, DETECTION AND BIOLOGICAL PROPERTIES

Directory of Open Access Journals (Sweden)

V. D. Naumenko

2013-10-01

Full Text Available Biological properties, chemical structures and biosynthesis pathways of plant isoflavones, especially soybean isoflavones (daidzein, genistein and glycitein are reviewed. The structures of isoflavones, and their aglicone and glucosides (glycosides forms as well as isoflavone biosynthesis pathways are described. General information about the advanced methods for the detection of isoflavones and their conjugates are considered. The importance of the profiling of isoflavones, flavonoids and their conjugates by means of analytical tools and methods to dissolve some questions in biology and medicine is discussed. The review provides data on the major isoflavone content in some vegetable crops and in the tissues of different soybean varieties. Health benefits and treatment or preventive properties of isoflavones for cancer, cardiovascular, endocrine diseases and metabolic disorders are highlighted. The mechanisms that may explain their positive biological effects are considered. The information on the application of advanced technologies to create new plant forms producing isoflavonoids with a predicted level of isoflavones, which is the most favorable for the treatment is given. The possibilities to use the metabolic engineering for the increasing of accumulation and synthesis of isoflavones at the non-legume crops such as tobacco, Arabidopsis and maize are considered. The examples how the plant tissues, which are not naturally produced of the isoflavones, can obtain potential for the synthesis of biologically active compounds via inducing of the activity of the introduced enzyme isoflavon synthase, are given. Specific biochemical pathways for increasing the synthesis of isoflavone genistein in Arabidopsis thaliana tissues are discussed. It is concluded that plant genetic engineering which is focused on modification of the secondary metabolites contain in plant tissues, enables to create the new crop varieties with improved agronomic properties and

BioBenchmark Toyama 2012: an evaluation of the performance of triple stores on biological data

Science.gov (United States)

2014-01-01

Background Biological databases vary enormously in size and data complexity, from small databases that contain a few million Resource Description Framework (RDF) triples to large databases that contain billions of triples. In this paper, we evaluate whether RDF native stores can be used to meet the needs of a biological database provider. Prior evaluations have used synthetic data with a limited database size. For example, the largest BSBM benchmark uses 1 billion synthetic e-commerce knowledge RDF triples on a single node. However, real world biological data differs from the simple synthetic data much. It is difficult to determine whether the synthetic e-commerce data is efficient enough to represent biological databases. Therefore, for this evaluation, we used five real data sets from biological databases. Results We evaluated five triple stores, 4store, Bigdata, Mulgara, Virtuoso, and OWLIM-SE, with five biological data sets, Cell Cycle Ontology, Allie, PDBj, UniProt, and DDBJ, ranging in size from approximately 10 million to 8 billion triples. For each database, we loaded all the data into our single node and prepared the database for use in a classical data warehouse scenario. Then, we ran a series of SPARQL queries against each endpoint and recorded the execution time and the accuracy of the query response. Conclusions Our paper shows that with appropriate configuration Virtuoso and OWLIM-SE can satisfy the basic requirements to load and query biological data less than 8 billion or so on a single node, for the simultaneous access of 64 clients. OWLIM-SE performs best for databases with approximately 11 million triples; For data sets that contain 94 million and 590 million triples, OWLIM-SE and Virtuoso perform best. They do not show overwhelming advantage over each other; For data over 4 billion Virtuoso works best. 4store performs well on small data sets with limited features when the number of triples is less than 100 million, and our test shows its

BioBenchmark Toyama 2012: an evaluation of the performance of triple stores on biological data.

Science.gov (United States)

Wu, Hongyan; Fujiwara, Toyofumi; Yamamoto, Yasunori; Bolleman, Jerven; Yamaguchi, Atsuko

2014-01-01

Biological databases vary enormously in size and data complexity, from small databases that contain a few million Resource Description Framework (RDF) triples to large databases that contain billions of triples. In this paper, we evaluate whether RDF native stores can be used to meet the needs of a biological database provider. Prior evaluations have used synthetic data with a limited database size. For example, the largest BSBM benchmark uses 1 billion synthetic e-commerce knowledge RDF triples on a single node. However, real world biological data differs from the simple synthetic data much. It is difficult to determine whether the synthetic e-commerce data is efficient enough to represent biological databases. Therefore, for this evaluation, we used five real data sets from biological databases. We evaluated five triple stores, 4store, Bigdata, Mulgara, Virtuoso, and OWLIM-SE, with five biological data sets, Cell Cycle Ontology, Allie, PDBj, UniProt, and DDBJ, ranging in size from approximately 10 million to 8 billion triples. For each database, we loaded all the data into our single node and prepared the database for use in a classical data warehouse scenario. Then, we ran a series of SPARQL queries against each endpoint and recorded the execution time and the accuracy of the query response. Our paper shows that with appropriate configuration Virtuoso and OWLIM-SE can satisfy the basic requirements to load and query biological data less than 8 billion or so on a single node, for the simultaneous access of 64 clients. OWLIM-SE performs best for databases with approximately 11 million triples; For data sets that contain 94 million and 590 million triples, OWLIM-SE and Virtuoso perform best. They do not show overwhelming advantage over each other; For data over 4 billion Virtuoso works best. 4store performs well on small data sets with limited features when the number of triples is less than 100 million, and our test shows its scalability is poor; Bigdata

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)

The synthesis and biological activity of some bile acid derivatives

International Nuclear Information System (INIS)

Kadirov, A.Kh.; Khaydarov, K.Kh.; Giyosov, A.Sh.

2000-01-01

In this monograph authors present the modified technologic scheme of receiving of 3α, 7α, 12α-three hydro xi cholanic acid with using of available raw materials for the synthesis products and for receiving on its base drugs diluent cholesterol gallstones of gall-bladder and bile-ducts

Evaluation of magnetic properties of NI-ZN ferrites obtained by different synthesis methods

International Nuclear Information System (INIS)

Simoes, A.N.; Neiva, L.S.; Simoes, V.N.; Gama, L.; Gomes Filho, A.C.; Oliveira, J.B.L.

2012-01-01

Ceramic oxides that exhibit ferromagnetic behavior represent important commercial products for the electronics industry and are commonly known as ferrites. The Ni-Zn ferrites are considered to be one of the most versatile and soft due to its high electrical resistivity and low eddy current losses. Thus, this study aims to evaluate the magnetic properties of Ni-Zn ferrite obtained by the Pechini and combustion reaction. After synthesis the powders were characterized by XRD, SEM, BET and magnetic measurements. The results showed that for both methods of synthesis used was the formation of the spinel phase of Ni-Zn ferrite. The micrographs show that the powders obtained by both methods have regular shapes and spherical. Were determined by BET surface area is 26 m 2 /g by the Pechini and 13 m 2 /g by combustion. And the samples synthesized by Pechini method obtained the best magnetic characteristics (author)

Synthesis of pyrido[1,2-a]benzimidazoles and other fused imidazole derivatives with a bridgehead nitrogen atom

Science.gov (United States)

Begunov, Roman S.; Ryzvanovich, Galina A.

2013-01-01

Main methods for the synthesis of fused imidazole derivatives with a bridgehead nitrogen atom are systematically considered and summarized. The reaction mechanisms that underlie the methods for the synthesis of pyrido[1,2-a]benzimidazoles and related compounds are described. Biological properties and mechanisms of the biological activity of fused azaheterocycles are discussed. The bibliography includes 152 references.

Radiosynthesis and biological evaluation of 5-(3-[18F]Fluoropropyloxy)-L-tryptophan for tumor PET imaging

International Nuclear Information System (INIS)

He, Shanzhen; Tang, Ganghua; Hu, Kongzhen; Wang, Hongliang; Wang, Shuxia; Huang, Tingting; Liang, Xiang; Tang, Xiaolan

2013-01-01

Introduction: [ 18 F]FDG PET has difficulty distinguishing tumor from inflammation in the clinic because of the same high uptake in nonmalignant and inflammatory tissue. In contrast, amino acid tracers do not accumulate in inflamed tissues and thus provide an excellent opportunity for their use in clinical cancer imaging. In this study, we developed a new amino acid tracer 5-(3-[ 18 F]Fluoropropyloxy)-L-tryptophan ([ 18 F]-L-FPTP) by two-step reactions and performed its biologic evaluation. Methods: [ 18 F]-L-FPTP was prepared by [ 18 F]fluoropropylation of 5-hydroxy-L-tryptophan disodium salt and purification on C18 cartridges. The biodistribution of [ 18 F]-L-FPTP was determined in normal mice and the incorporation of [ 18 F]-L-FPTP into tissue proteins was investigated. In vitro competitive inhibition experiments were performed with Hepa1-6 hepatoma cell lines. [ 18 F]-L-FPTP PET imaging was performed on tumor-bearing and inflammation mice and compared with [ 18 F]-L-FEHTP PET. Results: The overall uncorrected radiochemical yield of [ 18 F]-L-FPTP was 21.1 ± 4.4% with a synthesis time of 60 min, the radiochemical purity was more than 99%. Biodistribution studies demonstrate high uptake of [ 18 F]-L-FPTP in liver, kidney, pancreas, and blood at the early phase, and fast clearance in most tissues over the whole observed time. The uptake studies in Hepa1-6 cells suggest that [ 18 F]-L-FPTP is transported by the amino acid transport system B 0,+ , LAT2 and ASC. [ 18 F]-L-FPTP displays good stability and is not incorporated into proteins in vitro. PET imaging shows that [ 18 F]-L-FPTP can be a better potential PET tracer for differentiating tumor from inflammation than [ 18 F]FDG and 5-(3-[ 18 F]fluoroethyloxy)-L-tryptophan ([ 18 F]-L-FEHTP), with high [ 18 F]-L-FPTP uptake ratio (2.53) of tumor to inflammation at 60 min postinjection. Conclusions: Using [ 18 F]fluoropropyl derivatives as intermediates, the new tracer [ 18 F]-L-FPTP was achieved with good yield and

Synthesis and Biological Evaluation of a Chitobiose-Based Peptide N-Glycanase Inhibitor Library

NARCIS (Netherlands)

Witte, Martin D.; Horst, Danielle; Wiertz, Emmanuel J.H.J.; Marel, Gijsbert A. van der; Overkleeft, Herman S.

2009-01-01

Peptide N-glycanase (PNGase), the enzyme responsible for the deglycosylation of N-linked glycoproteins, has an active site related to that of cysteine proteases. Chitiobiose was equipped with electrophilic traps often used in cysteine protease inhibitors, and the resulting compounds were evaluated

Pyrrolizidine alkaloids: occurrence, biology, and chemical synthesis.

Science.gov (United States)

Robertson, Jeremy; Stevens, Kiri

2017-01-04

Covering: 2013 up to the end of 2015This review covers the isolation and structure of new pyrrolizidines; pyrrolizidine biosynthesis; biological activity, including the occurrence of pyrrolizidines as toxic components or contaminants in foods and beverages; and formal and total syntheses of naturally-occurring pyrrolizidine alkaloids and closely related non-natural analogues.

Synthetic Biology and Personalized Medicine

Science.gov (United States)

Jain, K.K.

2013-01-01

Synthetic biology, application of synthetic chemistry to biology, is a broad term that covers the engineering of biological systems with structures and functions not found in nature to process information, manipulate chemicals, produce energy, maintain cell environment and enhance human health. Synthetic biology devices contribute not only to improve our understanding of disease mechanisms, but also provide novel diagnostic tools. Methods based on synthetic biology enable the design of novel strategies for the treatment of cancer, immune diseases metabolic disorders and infectious diseases as well as the production of cheap drugs. The potential of synthetic genome, using an expanded genetic code that is designed for specific drug synthesis as well as delivery and activation of the drug in vivo by a pathological signal, was already pointed out during a lecture delivered at Kuwait University in 2005. Of two approaches to synthetic biology, top-down and bottom-up, the latter is more relevant to the development of personalized medicines as it provides more flexibility in constructing a partially synthetic cell from basic building blocks for a desired task. PMID:22907209

Synthesis of hydroxyapatite with the use of calcium carbonate as of the biological precursor; Sintese de hidroxiapatita com o uso de carbonato de calcio de origem biologica como precurssor

Energy Technology Data Exchange (ETDEWEB)

Aguilar, M.S.; Di Lello, B.C.; Queiroz, F.; Campos, N.C., E-mail: marilzasa@oi.com.br [Universidade Estacio de Sa (UESA), Rio de Janeiro, RJ (Brazil). Departamento de Engenharia; Campos, J.B. [Universidade do Estado do Rio de Janeiro (PPGEM/UERJ), RJ (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica

2014-07-01

This work describes the synthesis of hydroxyapatite from calcium from biological materials such as shells carbonate. In the syntheses performed, the calcium carbonate of biological origin was used as the precursor and through a precipitation reaction with phosphoric acid, was converted into calcium hydroxide. Sequentially, the precipitate was aged, filtered, washed, dried and calcined, and then transformed into hydroxyapatite. The characterization of the powders was performed by X-DR (X-ray diffraction) and SEM (scanning electron microscopy). DR-X as determined hydroxyapatite calcium phosphate phase calcium. SEM revealed a morphology of finely divided particles. The method B.E.T. showed values of specific area and volume of micropores consistent with the literature. The results of the characterizations proved feasible to use for obtaining biological hydroxyapatite materials used in the reaction conditions.(author)

Evaluation of the published biological bases for regulations concerning non-coherent light

International Nuclear Information System (INIS)

Sykes, S.M.; Bockstahler, L.; Felten, R.; Hellman, K.; Jacobson, E.; Krell, K.; Lytle, C.D.; Waxler, M.; Withrow, T.; Zaremba, T.

1981-01-01

The development of an information base of light-induced bioeffects data to support regulatory activities is a continuing process. Though standards covering the three spectral regions of light, ultraviolet (UV), visible, and infrared (IR), currently exist, attempts must regularly be made to assess the adequacy of these standards with respect to currently available biological information. In order to establish a starting point for these reassessments, the biological effects of light considered in establishing the standards must first be determined. Using this information, the strengths and weaknesses of each standard can be evaluated, and particularly important areas of future research can be determined. This document analyzes current standards covering non-coherent light with respect to the biological effects considered in their adoption. The current standards covering non-coherent light are based on few biological endpoints. The ACGIH standard for ultraviolet considers only skin erythema and eye keratitis; the visible light standard considers only retinal damage; and the infrared standard considers only lens cataracts. Clearly, other biological effects need to be considered. But any standard represents a state-of-the-art estimate of maximum allowable exposure levels, and while there is considerable qualitative information on many additional biological effects of light, there is little quantitative information. Without this information it is difficult either to incorporate these effects into the regulatory process or to determine if the current standards are adequate to cover them

Evaluation of biological control of fusarium wilt in gerbera with Trichoderma asperellum

OpenAIRE

Daiani Brandler; Luan Junior Divensi; Rodrigo José Tonin; Thalita Pedrozo Pilla; Ines Rezendes; Paola Mendes Milanesi

2017-01-01

The increase in flower cultivation in recent years has been reflecting the higher incidence of soil pathogens that can cause serious problems. This study aimed to evaluate the biological control of Fusarium wilt in gerbera with Trichoderma asperellum. The evaluated treatments were: T1) Control, only sterile substrate; T2) Substrate + Fusarium oxysporum; T3) Substrate + Fusarium oxysporum + Trichoderma asperellum; and T4) Substrate + Trichoderma asperellum. For this, the pathogen was isolated ...

Design, synthesis, and biological evaluation of 3-vinyl-quinoxalin-2(1H-one derivatives as novel antitumor inhibitors of FGFR1

Directory of Open Access Journals (Sweden)

Liu Z

2016-05-01

Full Text Available Zhiguo Liu,1,* Shufang Yu,1,* Di Chen,1 Guoliang Shen,1 Yu Wang,1 Leping Hou,2 Dan Lin,1 Jinsan Zhang,1 Faqing Ye1 1School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 2Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, People’s Republic of China *These authors contributed equally to this work Abstract: FGFR1 is well known as a molecular target in anticancer drug design. TKI258 plays an important role in RTK inhibitors. Utilizing TKI258 as a lead compound that contains a quinazolinone nucleus, we synthesized four series of 3-vinyl-quinoxalin-2(1H-one derivatives, a total of 27 compounds. We further evaluated these compounds for FGFR1 inhibition ability as well as cytotoxicity against four cancer cell lines (H460, B16-F10, Hela229, and Hct116 in vitro. Some compounds displayed good-to-excellent potency against the four tested cancer cell lines compared with TKI258. Structure–activity relationship analyses indicated that small substituents at the side chain of the 3-vinyl-quinoxalin-2(1H-one were more effective than large substituents. Lastly, we used molecular docking to obtain further insight into the interactions between the compounds and FGFR1. Keywords: FGFR1, synthesis, quinoxaline, antitumor activity, kinase inhibitor

Synthesis characterization and biological evaluation of a novel mixed ligand 99mTc complex as potential brain imaging agent

International Nuclear Information System (INIS)

Rey, A.; Manta, E.; Leon, A.; Papadopoulos, M.; Pirmettis, Y.; Raptopoulou, C.; Chiotellis, E.; Leon, E.; Mallo, L.

1998-01-01

One approach in the design of neutral oxotechnetium complexes is based on the simultaneous substitution of a tridentate dianionic ligand and a monodentate monoanionic coligand on a [Tc(V)O] +3 precursor. Following this ''mixed ligand'' concept, a novel 99m Tc complex with N,N-bis(2-mercaptoethyl)-N'N'-diethylethylenediamine as ligand and 1-octanethiol as coligand is prepared and evaluated as potential brain radiopharmaceutical. Preparation of the complex at tracer level was accomplished by using 99m Tc-glucoheptonate as precursor. The substitution was optimized and a coligand/ligand ratio of 5 was selected. Under this conditions the labeling yield was over 80% and a major product (with radiochemical purity > 80%) was isolated by HPLC methods and used for biological evaluation. Chemical characterization at carrier level was developed using the corresponding rhenium complex as structural model. The Re complex was also prepared by substitution method and isolated as a crystalline product. The crystals were characterized by UV-vis and IR spectra and elemental analysis. Results were consistent with the expected ReOLC structure. X ray crystallographic study demonstrated that the complex adopts a distorted trigonal bipyramidal geometry. The basal plane is defined by the SS atoms of the ligand and the oxo group, while the N of the ligand and the S of the colligand occupy the two apical positions. All sulphur atoms underwent ionization leading to the formation of a neutral compound. 99 Tc complex was also prepared. Although it was not isolated due to the small amount of reagents employed, the HPLC profile was identical to the one observed for the rhenium complex suggesting the same chemical structure. Biodistribution in mice demonstrated early brain uptake, fast blood clearance, excretion through hepatobiliary system and a brain/blood ratio that increased significantly with time. (author)

Adjuvant Biological Therapies in Chronic Leg Ulcers

Directory of Open Access Journals (Sweden)

Natalia Burgos-Alonso

2017-11-01

Full Text Available Current biological treatments for non-healing wounds aim to address the common deviations in healing mechanisms, mainly inflammation, inadequate angiogenesis and reduced synthesis of extracellular matrix. In this context, regenerative medicine strategies, i.e., platelet rich plasmas and mesenchymal stromal cell products, may form part of adjuvant interventions in an integral patient management. We synthesized the clinical experience on ulcer management using these two categories of biological adjuvants. The results of ten controlled trials that are included in this systematic review favor the use of mesenchymal stromal cell based-adjuvants for impaired wound healing, but the number and quality of studies is moderate-low and are complicated by the diversity of biological products. Regarding platelet-derived products, 18 controlled studies investigated their efficacy in chronic wounds in the lower limb, but the heterogeneity of products and protocols hinders clinically meaningful quantitative synthesis. Most patients were diabetic, emphasizing an unmet medical need in this condition. Overall, there is not sufficient evidence to inform routine care, and further clinical research is necessary to realize the full potential of adjuvant regenerative medicine strategies in the management of chronic leg ulcers.

Synthesis of O-Amino Sugars and Nucleosides

Directory of Open Access Journals (Sweden)

Na Chen

2018-03-01

Full Text Available Nucleic acids and carbohydrates are essential biomolecules involved in numerous biological and pathological processes. Development of multifunctional building blocks based on nucleosides and sugars is in high demand for the generation of novel oligonucleotide mimics and glycoconjugates for biomedical applications. Recently, aminooxyl-functionalized compounds have attracted increasing research interest because of their easy derivatization through oxime ligation or N-oxyamide formation reactions. Various biological applications have been reported for O-amino carbohydrate- and nucleoside-derived compounds. Here, we report our efforts in the design and synthesis of glyco-, glycosyl, nucleoside- and nucleo-aminooxy acid derivatives from readily available sugars and amino acids, and their use for the generation of N-oxyamide-linked oligosaccharides, glycopeptides, glycolipids, oligonucleosides and nucleopeptides as novel glycoconjugates or oligonucleotide mimics. Delicate and key points in the synthesis will be emphasized.

Synthetic Biology of Polyhydroxyalkanoates (PHA).

Science.gov (United States)

Meng, De-Chuan; Chen, Guo-Qiang

Microbial polyhydroxyalkanoates (PHA) are a family of biodegradable and biocompatible polyesters which have been extensively studied using synthetic biology and metabolic engineering methods for improving production and for widening its diversity. Synthetic biology has allowed PHA to become composition controllable random copolymers, homopolymers, and block copolymers. Recent developments showed that it is possible to establish a microbial platform for producing not only random copolymers with controllable monomers and their ratios but also structurally defined homopolymers and block copolymers. This was achieved by engineering the genome of Pseudomonas putida or Pseudomonas entomophiles to weaken the β-oxidation and in situ fatty acid synthesis pathways, so that a fatty acid fed to the bacteria maintains its original chain length and structures when incorporated into the PHA chains. The engineered bacterium allows functional groups in a fatty acid to be introduced into PHA, forming functional PHA, which, upon grafting, generates endless PHA variety. Recombinant Escherichia coli also succeeded in producing efficiently poly(3-hydroxypropionate) or P3HP, the strongest member of PHA. Synthesis pathways of P3HP and its copolymer P3HB3HP of 3-hydroxybutyrate and 3-hydroxypropionate were assembled respectively to allow their synthesis from glucose. CRISPRi was also successfully used to manipulate simultaneously multiple genes and control metabolic flux in E. coli to obtain a series of copolymer P3HB4HB of 3-hydroxybutyrate (3HB) and 4-hydroxybutyrate (4HB). The bacterial shapes were successfully engineered for enhanced PHA accumulation.

Synthesis, biological evaluation, and baboon PET imaging of the potential adrenal imaging agent cholesteryl-p-[{sup 18}f]fluorobenzoate

Energy Technology Data Exchange (ETDEWEB)

Jonson, Stephanie D.; Welch, Michael J. E-mail: welch@mirlink.wustl.edu

1999-01-01

Cholesteryl-p-[{sup 18}F]fluorobenzoate ([{sup 18}F]CFB) was investigated as a potential adrenal positron emission tomography (PET) imaging agent for the diagnostic imaging of adrenal disorders. We describe the synthesis, biodistribution, adrenal autoradiography, and baboon PET imaging of [{sup 18}F]CFB. The synthesis of [{sup 18}F]CFB was facilitated by the use of a specially designed microwave cavity that was instrumental in effecting 70-83% incorporation of fluorine-18 in 60 s via [{sup 18}F]fluoro-for-nitro exchange. Tissue distribution studies in mature female Sprague-Dawley rats showed good accumulation of [{sup 18}F]CFB in the steroid-secreting tissues, adrenals and ovaries, at 1 h postinjection. The effectiveness of [{sup 18}F]CFB to accumulate in diseased adrenals was shown through biodistribution studies in hypolipidemic rats, which showed a greater than threefold increase in adrenal uptake at 1 h and increased adrenal/liver and adrenal/kidney ratios. Analysis of the metabolites at 1 h in the blood, adrenals, spleen, and ovaries of hypolipidemic and control rats showed the intact tracer representing greater than 86%, 93%, 92%, and 82% of the accumulated activity, respectively. [{sup 18}F]CFB was confirmed to selectively accumulate in the adrenal cortex versus the adrenal medulla by autoradiography. Normal baboon PET imaging with [{sup 18}F]CFB effectively showed adrenal localization as early as 15 min after injection of the tracer, with enhanced adrenal contrast seen at 60-70 min. These results suggest that [{sup 18}F]CFB may be useful as an adrenal PET imaging agent for assessing adrenal disorders.

High-temperature Ionization-induced Synthesis of Biologically Relevant Molecules in the Protosolar Nebula

Science.gov (United States)

Bekaert, David V.; Derenne, Sylvie; Tissandier, Laurent; Marrocchi, Yves; Charnoz, Sebastien; Anquetil, Christelle; Marty, Bernard

2018-06-01

Biologically relevant molecules (hereafter biomolecules) have been commonly observed in extraterrestrial samples, but the mechanisms accounting for their synthesis in space are not well understood. While electron-driven production of organic solids from gas mixtures reminiscent of the photosphere of the protosolar nebula (PSN; i.e., dominated by CO–N2–H2) successfully reproduced key specific features of the chondritic insoluble organic matter (e.g., elementary and isotopic signatures of chondritic noble gases), the molecular diversity of organic materials has never been investigated. Here, we report that a large range of biomolecules detected in meteorites and comets can be synthesized under conditions typical of the irradiated gas phase of the PSN at temperatures = 800 K. Our results suggest that organic materials—including biomolecules—produced within the photosphere would have been widely dispersed in the protoplanetary disk through turbulent diffusion, providing a mechanism for the distribution of organic meteoritic precursors prior to any thermal/photoprocessing and subsequent modification by secondary parent body processes. Using a numerical model of dust transport in a turbulent disk, we propose that organic materials produced in the photosphere of the disk would likely be associated with small dust particles, which are coupled to the motion of gas within the disk and therefore preferentially lofted into the upper layers of the disk where organosynthesis occurs.

Synthesis and evaluation of new protecting agents against ionizing radiations; Synthese et evaluation de nouveaux agents de protection contre les rayonnements ionisants

Energy Technology Data Exchange (ETDEWEB)

Nadal, B.

2009-10-15

This thesis is devoted to the synthesis of new pulvinic acid derivatives and the evaluation of their antioxidant and radioprotective properties. This study has been conducted with the aim to develop new protecting agents against ionizing radiations. A new access to pulvinic acid derivatives was developed starting from L-dimethyl tartrate. It is based on a Dieckmann cyclization a dehydration and a Suzuki-Miyaura coupling. It allows a short effective preparation of various pulvinic acid derivatives: tetronic acid derivatives, mono-substituted pulvinic acid derivatives and methyl pulvinates. A modified method has been used to prepare pulvinones. This strategy gave access in four steps to the desired pulvinones. The rapidity of this method is provided by a tandem process, carried out in the final step, involving a Dieckmann cyclization and a {beta}-elimination. A synthesis of 3-aryltetramic acids has also been developed in order to prepare nitrogen derivatives of pulvinic acid. The antioxidant activity of the prepared compounds was then evaluated using various tests: DPPH, ABTS, protection of thymidine and DNA study of lipid peroxidation. These evaluations allowed to define interesting structure-activity relationships of pulvinic derivatives. They have shown that several derivatives have very good antioxidant activities. Finally, radioprotective tests on TK6 cells and mice have have been performed on selected compounds. (author)

Enzyme and microbial technology for synthesis of bioactive oligosaccharides: an update.

Science.gov (United States)

Chen, Rachel

2018-04-01

Oligosaccharides, in either free or bound forms, play crucial roles in a wide range of biological processes. Increasing appreciation of their roles in cellular communication, interaction, pathogenesis, and prebiotic functions has stimulated tremendous interests in their synthesis. Pure and structurally defined oligosaccharides are essential for fundamental studies. On the other hand, for those with near term medical and nutraceutical applications, their large-scale synthesis is necessary. Unfortunately, oligosaccharides are notoriously difficult in their synthesis, and their enormous diverse structures leave a vast gap between what have been synthesized in laboratory and those present in various biological systems. While enzymes and microbes are nature's catalysts for oligosaccharides, their effective use is not without challenges. Using examples of galactose-containing oligosaccharides, this review analyzes the pros and cons of these two forms of biocatalysts and provides an updated view on the status of biocatalysis in this important field. Over the past few years, a large number of novel galactosidases were discovered and/or engineered for improved synthesis via transglycosylation. The use of salvage pathway for regeneration of uridine diphosphate (UDP)-galactose has made the use of Leloir glycosyltransferases simpler and more efficient. The recent success of large-scale synthesis of 2' fucosyllactose heralded the power of whole-cell biocatalysis as a scalable technology. While it still lags behind enzyme catalysis in terms of the number of oligosaccharides synthesized, an acceleration in the use of this form of biocatalyst is expected as rapid advances in synthetic biology have made the engineering of whole cell biocatalysts less arduous and less time consuming.

Plant oligoadenylates: enzymatic synthesis, isolation, and biological activities

International Nuclear Information System (INIS)

Devash, Y.; Reichman, M.; Sela, I.; Reichenbach, N.L.; Suhadolnik, R.J.

1985-01-01

An enzyme that converts [ 3 H, 32 P]ATP, with a 3 H: 32 P ratio of 1:1, to oligoadenylates with the same 3 H: 32 P ratio was increased in plants following treatment with human leukocyte interferon or plant antiviral factor or inoculation with tobacco mosaic virus. The enzyme was extracted from tobacco leaves, callus tissue cultures, or cell suspension cultures. The enzyme, a putative plant oligoadenylate synthetase, was immobilized on poly(rI) . poly(rC)-agarose columns and converted ATP into plant oligoadenylates. These oligoadenylates were displaced from DEAE-cellulose columns with 350 mM KCl buffer, dialyzed, and further purified by high-performance liquid chromatography (HPLC) and DEAE-cellulose gradient chromatography. In all steps of purification, the ratio of 3 H: 32 P in the oligoadenylates remained 1:1. The plant oligoadenylates isolated by displacement with 350 mM KCl had a molecular weight greater than 1000. The plant oligoadenylates had charges of 5- and 6-. HPLC resolved five peaks, three of which inhibited protein synthesis in reticulocyte and wheat germ systems. Partial structural elucidation of the plant oligoadenylates has been determined by enzymatic and chemical treatments. An adenylate with a 3',5'-phosphodiester and/or a pyrophosphoryl linkage with either 3'- or 5'-terminal phosphates is postulated on the basis of treatment of the oligoadenylates with T2 RNase, snake venom phosphodiesterase, and bacterial alkaline phosphatase and acid and alkaline hydrolyses. The plant oligoadenylates at 8 X 10(-7) M inhibit protein synthesis by 75% in lysates from rabbit reticulocytes and 45% in wheat germ cell-free systems

Synthesis of potent G-quadruplex binders of macrocyclic heptaoxazole and evaluation of their activities.

Science.gov (United States)

Tera, Masayuki; Iida, Keisuke; Shin-ya, Kazuo; Nagasawa, Kazuo

2009-01-01

Guanine-rich DNA sequences form unique three-dimensional conformation known as G-quadruplexes (G-q). G-q structures have been found in telomere and in some oncogene promoter. Recently, it was suggested that G-q showed some biological activities including telomere shortening and transcriptional regulation. In this paper, we synthesized selective G-q binders and evaluated of their biological activities.

A preliminary synthesis of pollination biology in the Cape flora

CSIR Research Space (South Africa)

Rebelo, AG

1987-01-01

Full Text Available biology are covered. Chapters reviewing plant breeding systems, insect, bird, mammal and wind pollination, and gene flow are introduced by a perspective on the role of the fossil record in pollination biology. A speculative chapter on the constraints...

Novel approach for heterocyclization: a clean and efficient synthesis and biological evaluation of 4-oxothiazolidines under microwave technique

International Nuclear Information System (INIS)

Desai, Krunal G.; Desai, K.R.

2006-01-01

A new selective method has been developed for rapid synthesis of 2-(aryl)-3-[2-benzoimidazolythio)-acetamidyl]-4-oxothiazolidines 4a-j by the heterocyclization of 2-{(1H-benzemidazol)-ylthio}-N-benzylidene aceto hydrazide 3a-j with HSCH2COOH under microwave irradiation (MWI) is described. The reaction rate and yield is enhanced tremendously under MWI as compared to conventional methods. All the compounds have been screened for their antifungal activity against Candida albicans and Aspergillus niger, antibacterial activity against Escherchia coli and Staphylococcus aureus. In the primary screening, some of the compounds exhibited appreciable activity. The structures of the synthesized compounds 4a-j have been characterized on the basis of their elemental analysis, IR, HNMR and Mass spectral data. (author)

Synthetic biology: programming cells for biomedical applications.

Science.gov (United States)

Hörner, Maximilian; Reischmann, Nadine; Weber, Wilfried

2012-01-01

The emerging field of synthetic biology is a novel biological discipline at the interface between traditional biology, chemistry, and engineering sciences. Synthetic biology aims at the rational design of complex synthetic biological devices and systems with desired properties by combining compatible, modular biological parts in a systematic manner. While the first engineered systems were mainly proof-of-principle studies to demonstrate the power of the modular engineering approach of synthetic biology, subsequent systems focus on applications in the health, environmental, and energy sectors. This review describes recent approaches for biomedical applications that were developed along the synthetic biology design hierarchy, at the level of individual parts, of devices, and of complex multicellular systems. It describes how synthetic biological parts can be used for the synthesis of drug-delivery tools, how synthetic biological devices can facilitate the discovery of novel drugs, and how multicellular synthetic ecosystems can give insight into population dynamics of parasites and hosts. These examples demonstrate how this new discipline could contribute to novel solutions in the biopharmaceutical industry.

Evaluation of the FIR Example using Xilinx Vivado High-Level Synthesis Compiler

Energy Technology Data Exchange (ETDEWEB)

Jin, Zheming [Argonne National Lab. (ANL), Argonne, IL (United States); Finkel, Hal [Argonne National Lab. (ANL), Argonne, IL (United States); Yoshii, Kazutomo [Argonne National Lab. (ANL), Argonne, IL (United States); Cappello, Franck [Argonne National Lab. (ANL), Argonne, IL (United States)

2017-07-28

Compared to central processing units (CPUs) and graphics processing units (GPUs), field programmable gate arrays (FPGAs) have major advantages in reconfigurability and performance achieved per watt. This development flow has been augmented with high-level synthesis (HLS) flow that can convert programs written in a high-level programming language to Hardware Description Language (HDL). Using high-level programming languages such as C, C++, and OpenCL for FPGA-based development could allow software developers, who have little FPGA knowledge, to take advantage of the FPGA-based application acceleration. This improves developer productivity and makes the FPGA-based acceleration accessible to hardware and software developers. Xilinx Vivado HLS compiler is a high-level synthesis tool that enables C, C++ and System C specification to be directly targeted into Xilinx FPGAs without the need to create RTL manually. The white paper [1] published recently by Xilinx uses a finite impulse response (FIR) example to demonstrate the variable-precision features in the Vivado HLS compiler and the resource and power benefits of converting floating point to fixed point for a design. To get a better understanding of variable-precision features in terms of resource usage and performance, this report presents the experimental results of evaluating the FIR example using Vivado HLS 2017.1 and a Kintex Ultrascale FPGA. In addition, we evaluated the half-precision floating-point data type against the double-precision and single-precision data type and present the detailed results.

Synthesis, structure combined with conformational analysis, biological activities and docking studies of bis benzylidene cyclohexanone derivatives

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Gehad Lotfy

2017-07-01

Full Text Available We report the synthesis and biological evaluation of bis benzylidne cyclohexanone derivatives 2,6-di(4-fluorobenzylidenecyclohexanone 3a and (2E,6E‐2,6‐bis({[4‐(trifluoromethylphenyl]methylidene}cyclohexanone 3b. Compound 3b crystallized in the monoclinic space group P21/n with unit cell parameters a = 29.3527(12 Å, b = 8.3147(3 Å, c = 32.7452(14 Å, β = 112.437(2°, and V = 7386.8(5 Å3, Z = 16, and Rint = 0.072 at T = 100 K. The asymmetric unit contains four independent molecules, each of which has slight differences in the bond lengths and angles. One non-classical C11D–H11F⋯F3A hydrogen bond connects the molecules. Density functional theory was used to optimize the structures and calculate the natural charges, dipole moments, frontier molecular orbitals, and NMR and UV–Vis spectroscopic properties, which are discussed and compared with the experimental data. The synthetic derivatives were evaluated for α-glucosidase inhibitory activity, and we found that compound 3a (IC50 = 96.3 ± 0.51 μM is a potent α-glucosidase inhibitor, showing superior activity to the standard drug acarbose (IC50 = 841 ± 1.73 μM. Compound 3b (IC50 = 7.92 ± 1.3 μg/mL was found to be a potent antileishmanial compound, especially compared to the antileishmanial drugs pentamidine (IC50 = 5.09 ± 0.04 μM and amphotericine B (IC50 = 0.29 ± 0.05 μg/mL. In addition, 3a and 3b have cytotoxic effects against PC3 (prostate cancer, HeLa (cervical cancer, and MCF-3 (breast cancer cell lines. Docking study for compounds activity was performed with Openeye software in order to understanding their pose of interaction in the target receptors.

Synthesis and Biological Investigation of Antioxidant Pyrrolomorpholine Spiroketal Natural Products

Science.gov (United States)

Verano, Alyssa Leigh

The pyrrolomorpholine spiroketal natural product family is comprised of epimeric furanose and pyranose isomers. These compounds were isolated from diverse plant species, all of which are used as traditional Chinese medicines for the treatment of a variety of diseases. Notably, the spiroketal natural products acortatarins A and B exhibit antioxidant activity in a diabetic renal cell model, significantly attenuating hyperglycemia-induced production of reactive oxygen species (ROS), a hallmark of diabetic nephropathy. The xylapyrrosides, additional members of the family, also inhibit t-butyl hydroperoxide-induced cytotoxicity in rat vascular smooth muscle cells. Accordingly, these natural products have therapeutic potential for the treatment of oxidative stress-related pathologies, and synthetic access would provide an exciting opportunity to investigate bioactivity and mechanism of action. Herein, we report the stereoselective synthesis of acortatarins A and B, furanose members of the pyrrolomorpholine spiroketal family. Our synthetic route was expanded to synthesize the pyranose congeners, thus completing entire D-enantiomeric family of natural products. Efficient access towards these scaffolds enabled systematic analogue synthesis, investigation of mechanism-of-action, and the discovery of novel antioxidants.

Using of Quantum Dots in Biology and Medicine.

Science.gov (United States)

Pleskova, Svetlana; Mikheeva, Elza; Gornostaeva, Ekaterina

2018-01-01

Quantum dots are nanoparticles, which due to their unique physical and chemical (first of all optical) properties, are promising in biology and medicine. There are many ways for quantum dots synthesis, both in the form of nanoislands self-forming on the surfaces, which can be used as single-photon emitters in electronics for storing information, and in the form of colloidal quantum dots for diagnostic and therapeutic purposes in living systems. The paper describes the main methods of quantum dots synthesis and summarizes medical and biological ways of their use. The main emphasis is laid on the ways of quantum dots surface modification. Influence of the size and form of nanoparticles, charge on the surfaces of quantum dots, and cover type on the efficiency of internalization by cells and cell compartments is shown. The main mechanisms of penetration are considered.

Synthesis of Tetracyclic Diterpenoids with Pharmacologic Relevance

Czech Academy of Sciences Publication Activity Database

Šíša, Miroslav; Vaněk, Tomáš

2016-01-01

Roč. 22, č. 12 (2016), s. 1767-1807 ISSN 1381-6128 R&D Projects: GA MŠk(CZ) LD15006 Institutional support: RVO:61389030 Keywords : Diterpenoids * synthesis * biological activity Subject RIV: CE - Biochemistry Impact factor: 2.611, year: 2016

Synthesis and preliminary study of 99mTc-mercaptoacetyl-triglycine (99mTc-MAG3) for radiolabeling of immune globulins

International Nuclear Information System (INIS)

Reyes, L.; Navarrete, M.

2001-01-01

The synthesis of a complex molecule with its coordination center composed by a triamide monomercaptide tetradentate set of donor groups plus a phenyl-acetyl group as protector group of a sulphur atom is reported. This compound has been mixed with immune globulin G, labeled with 99m Tc and purified by high resolution liquid chromatography (HRLC). The biological behavior of this labeled compound was evaluated with mice of Balb-C origin, showing the biological properties of a protein. This molecule might be another option for radio-immuno-scintigraphic analysis when using proteins of antigenic nature. (author)

Microwave-assisted synthesis and antioxidant properties of hydrazinyl thiazolyl coumarin derivatives

Directory of Open Access Journals (Sweden)

Osman Hasnah

2012-04-01

Full Text Available Abstract Background Coumarin derivatives exhibit a wide range of biological properties including promising antioxidant activity. Furthermore, microwave-assisted organic synthesis has delivered rapid routes to N- and O-containing heterocycles, including coumarins and thiazoles. Combining these features, the use of microwave-assisted processes will provide rapid access to a targeted coumarin library bearing a hydrazino pharmacophore for evaluation of antioxidant properties Results Microwave irradiation promoted 3 of the 4 steps in a rapid, convergent synthesis of a small library of hydrazinyl thiazolyl coumarin derivatives, all of which exhibited significant antioxidant activity comparable to that of the natural antioxidant quercetin, as established by DPPH and ABTS radical assays Conclusions Microwave dielectric heating provides a rapid and expedient route to a series of hydrazinyl thiazolyl coumarins to investigate their radical scavenging properties. Given their favourable properties, in comparison with known antioxidants, these coumarin derivatives are promising leads for further development and optimization.

Synthesis and biological evaluation of PMMA/MMT nanocomposite as denture base material.

Science.gov (United States)

Zheng, Junping; Su, Qiang; Wang, Chen; Cheng, Gang; Zhu, Ran; Shi, Jin; Yao, Kangde

2011-04-01

Inorganic-polymer nanocomposites are of significant interest for emerging materials due to their improved properties and unique combination of properties. Poly (methylmethacrylate) (PMMA)/montmorillonite (MMT) nanocomposites were prepared by in situ suspension polymerization with dodecylamine used as MMT-modifier. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to characterize the structures of the nanocomposites. Cytotoxicity test, hemolysis test, acute systemic toxicity test, oral mucous membrane irritation test, guinea-pig maximization test and mouse bone-marrow micronucleus test were used to evaluate the biocompatibility of PMMA/MMT nanocomposites. The results indicated that an exfoliated nanocomposite was achieved, and the resulting nanocomposites exhibited excellent biocompatibility as denture base material and had potential application in dental materials.

Hibiscus latent Fort Pierce virus in Brazil and synthesis of its biologically active full-length cDNA clone.

Science.gov (United States)

Gao, Ruimin; Niu, Shengniao; Dai, Weifang; Kitajima, Elliot; Wong, Sek-Man

2016-10-01

A Brazilian isolate of Hibiscus latent Fort Pierce virus (HLFPV-BR) was firstly found in a hibiscus plant in Limeira, SP, Brazil. RACE PCR was carried out to obtain the full-length sequences of HLFPV-BR which is 6453 nucleotides and has more than 99.15 % of complete genomic RNA nucleotide sequence identity with that of HLFPV Japanese isolate. The genomic structure of HLFPV-BR is similar to other tobamoviruses. It includes a 5' untranslated region (UTR), followed by open reading frames encoding for a 128-kDa protein and a 188-kDa readthrough protein, a 38-kDa movement protein, 18-kDa coat protein, and a 3' UTR. Interestingly, the unique feature of poly(A) tract is also found within its 3'-UTR. Furthermore, from the total RNA extracted from the local lesions of HLFPV-BR-infected Chenopodium quinoa leaves, a biologically active, full-length cDNA clone encompassing the genome of HLFPV-BR was amplified and placed adjacent to a T7 RNA polymerase promoter. The capped in vitro transcripts from the cloned cDNA were infectious when mechanically inoculated into C. quinoa and Nicotiana benthamiana plants. This is the first report of the presence of an isolate of HLFPV in Brazil and the successful synthesis of a biologically active HLFPV-BR full-length cDNA clone.

Novel multi-targeted agents for Alzheimer's disease: Synthesis, biological evaluation, and molecular modeling of novel 2-[4-(4-substitutedpiperazin-1-yl)phenyl]benzimidazoles.

Science.gov (United States)

Ozadali-Sari, Keriman; Tüylü Küçükkılınç, Tuba; Ayazgok, Beyza; Balkan, Ayla; Unsal-Tan, Oya

2017-06-01

The present study describes the synthesis, pharmacological evaluation (BChE/AChE inhibition, Aβ antiaggregation, and neuroprotective effects), and molecular modeling studies of novel 2-[4-(4-substitutedpiperazin-1-yl)phenyl]benzimidazole derivatives. The alkyl-substituted derivatives exhibited selective inhibition on BChE with varying efficiency. Compounds 3b and 3d were found to be the most potent inhibitors of BChE with IC 50 values of 5.18 and 5.22μM, respectively. The kinetic studies revealed that 3b is a partial non-competitive BChE inhibitor. Molecular modeling studies also showed that the alkyl-substituted derivatives were able to reach the catalytic anionic site of the BChE. The compounds with an inhibitory effect on BChE were subsequently screened for their Aβ antiaggregating and neuroprotective activities. Compounds 3a and 3b exerted a potential neuroprotective effect against H 2 O 2 and Aβ-induced cytotoxicity in SH-SY5Y cells. Collectively, 3b was found as the most promising compound for the development of multi-target directed ligands against Alzheimer's disease. Copyright © 2017 Elsevier Inc. All rights reserved.

Synthesis of the 4’-desmethoxy analogue of RU79115

Directory of Open Access Journals (Sweden)

MICHEL KLICH

2004-11-01

Full Text Available The synthesis, and biological activity in vitro of the 4’-desmethoxy analogue (3 of RU 79115 (2 is described. Comparison of the biological activity of the two analogues clearly indicated the importance of the 4’-methoxy group in conferring good gyrase B inhibitory activity as well as antibacterial activity.

Structural Studies of Silver Nanoparticles Obtained Through Single-Step Green Synthesis

Science.gov (United States)

Prasad Peddi, Siva; Abdallah Sadeh, Bilal

2015-10-01

Green synthesis of silver Nanoparticles (AGNP's) has been the most prominent among the metallic nanoparticles for research for over a decade and half now due to both the simplicity of preparation and the applicability of biological species with extensive applications in medicine and biotechnology to reduce and trap the particles. The current article uses Eclipta Prostrata leaf extract as the biological species to cap the AGNP's through a single step process. The characterization data obtained was used for the analysis of the sample structure. The article emphasizes the disquisition of their shape and size of the lattice parameters and proposes a general scheme and a mathematical model for the analysis of their dependence. The data of the synthesized AGNP's has been used to advantage through the introduction of a structural shape factor for the crystalline nanoparticles. The properties of the structure of the AGNP's proposed and evaluated through a theoretical model was undeviating with the experimental consequences. This modus operandi gives scope for the structural studies of ultrafine particles prepared using biological methods.

Synthesis and Sensory Evaluation of ent-Kaurane Diterpene Glycosides

Directory of Open Access Journals (Sweden)

Venkata Sai Prakash Chaturvedula

2012-07-01

Full Text Available Catalytic hydrogenation of the three ent-kaurane diterpene glycosides isolated from Stevia rebaudiana, namely rubusoside, stevioside, and rebaudioside-A has been carried out using Pd(OH₂ and their corresponding dihydro derivatives have been isolated as the products. Synthesis of reduced steviol glycosides was performed using straightforward chemistry and their structures were characterized on the basis of 1D and 2D NMR spectral data and chemical studies. Also, we report herewith the sensory evaluation of all the reduced compounds against their corresponding original steviol glycosides and sucrose for the sweetness property of these molecules.

Synthesis and biological evaluation in rat and cat of [18F]12ST05 as a potential 5-HT6 PET radioligand

International Nuclear Information System (INIS)

Tang, Sandrine; Verdurand, Mathieu; Joseph, Benoit; Lemoine, Laetitia; Daoust, Alexia; Billard, Thierry; Fournet, Guy; Le Bars, Didier; Zimmer, Luc

2007-01-01

Introduction: 5-hydroxytryptamine (5-HT) 6 receptors represent one of the more recently discovered serotoninergic receptor family. However, no 5-HT 6 positron emission tomography (PET) radiotracer is currently used in clinical imaging studies. The purpose of this study was to propose the first fluorinated PET radiotracer for this brain receptor. Methods: A new compound presenting in vitro high affinity towards the serotoninergic 5-HT 6 receptor, N-[2-(1-[(4-fluorophenyl)sulfonyl]-1H-indol-4-yloxy)ethyl] -N,N-dimethylamine, was labelled with fluorine 18 via a nitro-/fluoronucleophilic substitution. Biological evaluations included (i) in vitro and ex vivo autoradiographies in rat brain and (ii) a PET scan on anaesthetized cat. Results and Conclusion: Although the radioligand showed excellent brain penetration, it did not reveal any specific binding to the 5-HT 6 receptors indicating that this radiotracer is not suitable for mapping 5-HT 6 receptors using PET

Synthesis of a Benzene-containing C1-Phosphonate Analogue of UDP-GlcNAc for the Inhibition of O-GlcNAc Transferase

Energy Technology Data Exchange (ETDEWEB)

Im, Jungkyun [Soonchunhyang Univ., Asan (Korea, Republic of)

2016-01-15

I report here the design, synthesis, and biological evaluation of a new C1-phosphonate analogue of UDP-GlcNAc as a potential inhibitor of OGT, an enzyme responsible for O-GlcNAc modification. The analogue was designed to mimic the transition state of the natural donor involved in the enzymatic reaction. However, the analogue showed somehow low activity as an inhibitor of OGT.

Evaluation of a fungal collection as certified reference material producer and as a biological resource center

Directory of Open Access Journals (Sweden)

Tatiana Forti

2016-06-01

Full Text Available Abstract Considering the absence of standards for culture collections and more specifically for biological resource centers in the world, in addition to the absence of certified biological material in Brazil, this study aimed to evaluate a Fungal Collection from Fiocruz, as a producer of certified reference material and as Biological Resource Center (BRC. For this evaluation, a checklist based on the requirements of ABNT ISO GUIA34:2012 correlated with the ABNT NBR ISO/IEC17025:2005, was designed and applied. Complementing the implementation of the checklist, an internal audit was performed. An evaluation of this Collection as a BRC was also conducted following the requirements of the NIT-DICLA-061, the Brazilian internal standard from Inmetro, based on ABNT NBR ISO/IEC 17025:2005, ABNT ISO GUIA 34:2012 and OECD Best Practice Guidelines for BRCs. This was the first time that the NIT DICLA-061 was applied in a culture collection during an internal audit. The assessments enabled the proposal for the adequacy of this Collection to assure the implementation of the management system for their future accreditation by Inmetro as a certified reference material producer as well as its future accreditation as a Biological Resource Center according to the NIT-DICLA-061.

Students' Ability to Solve Process-Diagram Problems in Secondary Biology Education

Science.gov (United States)

Kragten, Marco; Admiraal, Wilfried; Rijlaarsdam, Gert

2015-01-01

Process diagrams are important tools in biology for explaining processes such as protein synthesis, compound cycles and the like. The aim of the present study was to measure the ability to solve process-diagram problems in biology and its relationship with prior knowledge, spatial ability and working memory. For this purpose, we developed a test…

Biologically active perspective synthesis of heteroannulated 8-nitroquinolines with green chemistry approach.

Science.gov (United States)

Arasakumar, Thangaraj; Mathusalini, Sadasivam; Gopalan, Subashini; Shyamsivappan, Selvaraj; Ata, Athar; Mohan, Palathurai Subramaniam

2017-04-01

A new class of pyrazolo[4,3-c]quinoline (5a-i, 7a-b) and pyrano[3,2-c]quinoline (9a-i) derivatives were designed and synthesized in moderate to good yields by microwave conditions. To enhance the yield of pyrano[3,2-c]quinoline derivatives, multicomponent one-pot synthesis has been developed. The synthesized compounds were identified by spectral and elemental analyses. Compounds 9a and 9i showed good antibacterial activity against Gram-positive and Gram-negative bacterial strains. All of the new compounds exhibited weak to moderate antioxidant activity, compound 9d exerted significant antioxidant power. The cytotoxicity of these compounds were also evaluated against MCF-7 (breast) and A549 (Lung) cancer cell lines. Most of the compounds displayed moderate to good cytotoxic activity against these cell lines. Compound 9i was found to be significantly active in this assay and also induced cell death by apoptosis. Molecular docking studies were carried out using EGFR inhibitor in order to determine the molecular interactions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Why magnetic and electromagnetic effects in biology are irreproducible and contradictory?

Science.gov (United States)

Buchachenko, Anatoly

2016-01-01

The main source of magnetic and electromagnetic effects in biological systems is now generally accepted and demonstrated in this paper to be radical pair mechanism which implies pairwise generation of radicals in biochemical reactions. This mechanism was convincingly established for enzymatic adenosine triphosphate (ATP) and desoxynucleic acid (DNA) synthesis by using catalyzing metal ions with magnetic nuclei ((25)Mg, (43)Ca, (67)Zn) and supported by magnetic field effects on these reactions. The mechanism, is shown to function in medicine as a medical remedy or technology (trans-cranial magnetic stimulation, nuclear magnetic control of the ATP synthesis in heart muscle, the killing of cancer cells by suppression of DNA synthesis). However, the majority of magnetic effects in biology remain to be irreproducible, contradictory, and enigmatic. Three sources of such a state are shown in this paper to be: the presence of paramagnetic metal ions as a component of enzymatic site or as an impurity in an uncontrollable amount; the property of the radical pair mechanism to function at a rather high concentration of catalyzing metal ions, when at least two ions enter into the catalytic site; and the kinetic restrictions, which imply compatibility of chemical and spin dynamics in radical pair. It is important to keep in mind these factors to properly understand and predict magnetic effects in magneto-biology and biology itself and deliberately use them in medicine. © 2015 Wiley Periodicals, Inc.

Prodrugs of Pyrazolo[3,4-d]pyrimidines: From Library Synthesis to Evaluation as Potential Anticancer Agents in an Orthotopic Glioblastoma Model.

Science.gov (United States)

Vignaroli, Giulia; Iovenitti, Giulia; Zamperini, Claudio; Coniglio, Federica; Calandro, Pierpaolo; Molinari, Alessio; Fallacara, Anna Lucia; Sartucci, Andrea; Calgani, Alessia; Colecchia, David; Mancini, Andrea; Festuccia, Claudio; Dreassi, Elena; Valoti, Massimo; Musumeci, Francesca; Chiariello, Mario; Angelucci, Adriano; Botta, Maurizio; Schenone, Silvia

2017-07-27

Pyrazolo[3,4-d]pyrimidines are potent protein kinase inhibitors with promising antitumor activity but suboptimal aqueous solubility, consequently worth being further optimized. Herein, we present the one-pot two-step procedure for the synthesis of a set of pyrazolo[3,4-d]pyrimidine prodrugs (1a-8a and 9a-e) with higher aqueous solubility and enhanced pharmacokinetic and therapeutic properties. ADME studies demonstrated for the most promising prodrugs a better aqueous solubility, a favorable hydrolysis in human and murine serum, and an increased ability to cross cell membranes with respect to the parental drugs, explaining their better 24 h in vitro cytotoxicity against human glioblastoma U87 cell line. Finally, the 4-4a couple of drug/prodrug was also evaluated in vivo, revealing a profitable pharmacokinetic profile of the prodrug associated with a good efficacy. The application of the prodrug approach demonstrated to be a successful strategy for improving aqueous solubility of the parental drugs, determining a positive impact also in their biological efficacy.

Synthesis and In Vitro and In Vivo Evaluation of Iodine-131-Labeled Folates: Potential Molecular Diagnostic and Therapeutic Radiopharmaceuticals

International Nuclear Information System (INIS)

Al Jammaz, I.

2009-01-01

Molecular targeting imaging has a great potential to be able to image molecular changes that are currently defined as predisease states which facilitate earlier detection of cancer and consequently, the greatest chance of cure. Advancement of scintigraphic imaging and radiotherapy is highly determined by development of more specific radiotracers. The Membrane-associated-folic acid receptor is a glycosylphospstidylinositol protein that overexpressed in approximately 100% of serious ovarian adenocarcinomas and various epithelial cancers including cervical, colorectal and renal cancers. Meanwhile, this receptor is highly restricted in most normal tissues which make these tumors as an excellent candidates for molecular targeting imaging and therapy through the folate receptor system. As part of our on-going research effort to develop prosthetic precursors for radiohalogenation of bioactive molecules, we have previously reported the synthesis and biological characterization of [ 18 F]- fluorobenzene and pyridine carbohydrazide-folate conjugates ([ 18 F]-SFB and [ 18 F]-SFP-folates). We here report the synthesis and biological characterization of [ 131 I]-iodobenzenecarbohydrazide-folate conjugate ([ 131 I]-SIB-folate) as a potential therapeutic radiopharmaceutical. The synthetic approaches for preparation of [ 131 I]iodobenzene carbohydrazide-folates ([ 131 I]-SIB-folate) entailed sequence of reactions. Hydrazide-folate was reacted with N-succinimidyl-m-[131I]-iodobenzoate-carboxylate ([ 131 I]-SIB) to give [ 131 I]-SIB-folate conjugate. Radiochemical yield was greater than 80% and synthesis times were ranging between 40-45 min. Radiochemical purity was also greater than 97% without HPLC purification. These synthetic approaches hold considerable promise as rapid and simple method for the radiohalogenation of folate in high radiochemical yield in short time. In vitro tests on KB cell line has shown that significant amount of the radioconjugate associated with cell

Synthesis and structure-activity relationship studies of furan-ring fused chalcones as antiproliferative agents.

Science.gov (United States)

Saito, Yusuke; Kishimoto, Maho; Yoshizawa, Yuko; Kawaii, Satoru

2015-02-01

As part of our continuing investigation of flavonoid derivatives as potential anticancer substances, the synthesis of 25 cinnamoyl derivatives of benzofuran as furan-fused chalcones was carried-out and these compounds were further evaluated for their antiproliferative activity towards HL60 promyelocytic leukemia cells. In comparison with 2',4'-dihydroxychalcone, attachment of a furan moiety on the A-ring enhanced activity by more than twofold. Benzofurans may be useful in the design of biologically active flavonoids. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

An efficient domino one-pot synthesis of novel spirofuran ...

Indian Academy of Sciences (India)

AFSHIN YAZDANI-ELAH-ABADI

Abstract. A simple and convenient multi-component domino reaction has been described for the synthesis of novel ... interest due to their pharmaceutical and biological activ- ..... We gratefully acknowledge financial support from the Research.

The Modern Synthesis in the Light of Microbial Genomics.

Science.gov (United States)

Booth, Austin; Mariscal, Carlos; Doolittle, W Ford

2016-09-08

We review the theoretical implications of findings in genomics for evolutionary biology since the Modern Synthesis. We examine the ways in which microbial genomics has influenced our understanding of the last universal common ancestor, the tree of life, species, lineages, and evolutionary transitions. We conclude by advocating a piecemeal toolkit approach to evolutionary biology, in lieu of any grand unified theory updated to include microbial genomics.

Occurrence, biological activity and synthesis of drimane sesquiterpenoids

NARCIS (Netherlands)

Jansen, B.J.M.; Groot, de Æ.

2004-01-01

In this review the names, structures and occurrence of all new drimanes and rearranged drimanes, which have been published between January 1990 and January 2003 have been collected. Subjects that have been treated are biosynthesis, analysis, biological activities, with special attention to cytotoxic

Synthesis and biological evaluation of branched and conformationally restricted analogs of the anticancer compounds 3'-C-ethynyluridine (EUrd) and 3'-C-ethynylcytidine (ECyd)

DEFF Research Database (Denmark)

Hrdlicka, Patrick J; Andersen, Nicolai K; Jepsen, Jan S

2005-01-01

The synthesis of branched and conformationally restricted analogs of the anticancer nucleosides 3'-C-ethynyluridine (EUrd) and 3'-C-ethynylcytidine (ECyd) is presented. Molecular modeling and (1)H NMR coupling constant analysis revealed that the furanose rings of all analogs except the LNA analog...

Micro-segmented flow applications in chemistry and biology

CERN Document Server

Cahill, Brian

2014-01-01

The book is dedicated to the method and application potential of micro segmented flow. The recent state of development of this powerful technique is presented in 12 chapters by leading researchers from different countries. In the first section, the principles of generation and manipulation of micro-fluidic segments are explained. In the second section, the micro continuous-flow synthesis of different types of nanomaterials is shown as a typical example for the use of advantages of the technique in chemistry. In the third part, the particular importance of the technique in biotechnical applications is presented demonstrating the progress for miniaturized cell-free processes, for molecular biology and DNA-based diagnostis and sequencing as well as for the development of antibiotics and the evaluation of toxic effects in medicine and environment.

Influence of reaction medium during synthesis of Gantrez AN 119 nanoparticles for oral vaccination.

Science.gov (United States)

Vandamme, Katrien; Melkebeek, Vesna; Cox, Eric; Deforce, Dieter; Lenoir, Joke; Adriaens, Els; Vervaet, Chris; Remon, Jean Paul

2010-02-01

Two synthesis methods of poly(methyl vinyl ether-co-maleic anhydride) (Gantrez AN 119) nanoparticles (NP) (used for oral vaccination) were compared. Wheat germ agglutinin (WGA) was used as ligand to enhance the bioadhesive properties of NP and beta-galactosidase as antigen. The first method encapsulated beta-galactosidase in NP by co-precipitation in an acetone/water mixture containing 44% acetone. In the second method, antigen addition occurred in 100% acetone. To improve stability, NP were crosslinked with 1,3-diaminopropane. The stability of WGA-conjugated NP with encapsulated antigen diminished at lower pH and when decreasing the amount of crosslinker. The binding type between WGA and polymer depended on the synthesis method: predominantly ionic bonds were formed using the 44% acetone method, whereas synthesis via the 100% acetone method resulted in covalent bonds. The biological activity of the WGA coating, evaluated via a pig gastric mucin binding test, was lower in NP prepared via the 100% acetone method. No release of native antigen was detected after hydrolysis of NP, due to the covalent antigen binding during antigen encapsulation and the high reactivity of the polymer. Moreover, the mucosal irritation capacity was evaluated upon nanoparticle hydrolysis using a slug mucosal irritation assay. Herein, hydrolysed NP of the 44% acetone method were classified as mild irritative. Copyright (c) 2009 Elsevier B.V. All rights reserved.

Mechanochemical synthesis evaluation of nanocrystalline bone-derived bioceramic powder using for bone tissue engineering

Directory of Open Access Journals (Sweden)

Amirsalar Khandan

2014-01-01

Full Text Available Introduction: Bone tissue engineering proposes a suitable way to regenerate lost bones. Different materials have been considered for use in bone tissue engineering. Hydroxyapatite (HA is a significant success of bioceramics as a bone tissue repairing biomaterial. Among different bioceramic materials, recent interest has been risen on fluorinated hydroxyapatites, (FHA, Ca 10 (PO 4 6 F x (OH 2−x . Fluorine ions can promote apatite formation and improve the stability of HA in the biological environments. Therefore, they have been developed for bone tissue engineering. The aim of this study was to synthesize and characterize the FHA nanopowder via mechanochemical (MC methods. Materials and Methods: Natural hydroxyapatite (NHA 95.7 wt.% and calcium fluoride (CaF 2 powder 4.3 wt.% were used for synthesis of FHA. MC reaction was performed in the planetary milling balls using a porcelain cup and alumina balls. Ratio of balls to reactant materials was 15:1 at 400 rpm rotation speed. The structures of the powdered particles formed at different milling times were evaluated by X-ray diffraction (XRD, scanning electron microscopy (SEM and transmission electron microscopy (TEM. Results: Fabrication of FHA from natural sources like bovine bone achieved after 8 h ball milling with pure nanopowder. Conclusion: F− ion enhances the crystallization and mechanical properties of HA in formation of bone. The produced FHA was in nano-scale, and its crystal size was about 80-90 nm with sphere distribution in shape and size. FHA powder is a suitable biomaterial for bone tissue engineering.

Synthesis and biological evaluation of 125I-erythropoietin as a potential radiopharmaceutical agent for tumours

International Nuclear Information System (INIS)

Clemente, Goncalo dos Santos; Duarte, Vera Lucia Serra

2011-01-01

Erythropoietin (EPO) is a glycoprotein hormone responsible for regulating erythropoiesis. Expression of EPO and EPO receptors (EPOr) has recently been demonstrated in some neoplastic cell lines and tumours, suggesting a potential new target for therapy. In this work, EPO was labeled with iodine-125 using the lactoperoxidase method, known to prevent damage to protein during radioiodination, and labeling conditions were optimized. In vitro stability studies have shown that 125 I-EPO is radiochemically stable for 20 days after radiolabeling. In vitro cell binding studies have demonstrated very low binding ( 125 I-EPO. In mice with induced melanoma, only a residual fixation in the tumour was evident. Further studies are warranted on other tumoral cell lines to better understand the binding process and internalization into cells. Studies on EPO labeled with carbon-11 could be valuable, since there is a greater chance of preserving the biological activity of the protein using this method. (author)

Novel synthesis of nanosilver particles using plant active principle aloin and evaluation of their cytotoxic effect against Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Thota Venkata Chaitanya Kumar

2014-02-01

Full Text Available Objective: To develop a reliable, eco-friendly and easy process for the synthesis of silver nanoparticles using aloin, the active principle of medicinal plant ‘Aloe vera ’ and to evaluate antimicrobial activity against Staphylococcus aureus (S. aureus, a causative organism of most of the diseases in livestock and to standardize the level of safety of synthesized silver nanoparticles. Methods: Characterization using UV-vis spectrophotometry, DLS technique, FT-IR and SEM. Tube dilution method was carried out to evaluate the MIC of the compound against S. aureus. MTT assay was performed to evaluate the level of safety of nanoparticles. Results: UV-vis absorption spectrum showed a maximum absorption around 200 nm for aloin mediated silver nanoparticles (ANS. The size of the particles as measured by DLS technique was 67.8 nm. The results of FT-IR analysis indicated the involvement of hydroxyl, carboxyl, amine and nitrile groups in the synthesis and stabilization of aloin mediated silver nanoparticles. SEM images showed that ANS with cubical, rectangular, triangular and spherical morphology and measured sizes of the agglomerated nanoparticles are in a range of 287.5 to 293.2 nm, however the average size of an individual particle is estimated to be approximately 70 nm. The compound (ANS showed a MIC of 21.8 ng/mL against S. aureus and showed an in vitro spleenocyte viability of more than 80% at the highest concentration of 87.5 mg/L per well. Conclusions: Aloin consists of functional groups which reduced Ag+ ions to Ago ions and helped in synthesis of silver nanoparticles. The synthesis process has further enhanced the antimicrobial activity of nanosilver. The compound is also proved to be safe at the level many times higher than the MIC.

Physicochemical characterization of microwave assisted synthesis of silver nanoparticles using Aloe Vera (Aloe barbadensis)

Science.gov (United States)

Kuponiyi, Abiola John

Biosynthesis of silver nanoparticles (AgNP) using different biological extracts is gaining recognition for its numerous applications in different disciplines. Although different approaches (physical and chemical) have been used for the synthesis of AgNP, the green chemistry method is most preferable because of its high efficacy, cost effectiveness, and environmental benignity. Aloe Vera (AV) contains chemical compounds (anthraquinones) that are known to possess antibacterial, antivirus and anticancer properties and the extract is a good chemical reduction agent for AgNP. Hence, it was hypothesized that a microwave assisted synthesis will produce highly concentrated, homogeneous, stable and biologically active AgNP. Thus, the main objective of the study was to evaluate the effect of microwave assisted synthesis of AgNP, the effect of pulse laser treatment on size reduction of a microwave synthesized AgNP, and the physicochemical characterization of AgNP synthesized with Aloe Vera water and ethanol extract. The experiment was conducted in two phases. Phase 1 was first conducted to optimize the experimental variables, thus establishing the optimum variables to apply in the second phase. The experiment in Phase 1 was conducted using three-factor factorial experimental design comprised of the following factors: 1) Extraction Solvent, 2) Heating Methods, 3) pH; and their corresponding levels were water and ethanol, conventional and microwave, pH (7, 8, 10 and 12), respectively. All synthesis was conducted at constant temperature of 80°C. Phase II experimental treatments were Laser ablation (0, 5, and 10 min) and Storage time (Week 1, 2 & 3). The Phase I of the results showed that increased AgNP concentrations were significantly (p 0.05) impact the particle size distribution. Hence, the Zeta potential of the particles has values typically ranging between +100 mV to -100 mV, hence indicative of colloidal stability matrix. Furthermore, the Polydispersity indexes of Week 1

First- and second-generation total synthesis of ciguatoxin CTX3C.

Science.gov (United States)

Inoue, Masayuki; Miyazaki, Keisuke; Uehara, Hisatoshi; Maruyama, Megumi; Hirama, Masahiro

2004-08-17

More than 20,000 people suffer annually from ciguatera seafood poisoning in subtropical and tropical regions. The extremely low content of the causative neurotoxins, designated as ciguatoxins, in fish has hampered isolation, detailed biological studies, and preparation of anti-ciguatoxin antibodies for detecting these toxins. Furthermore, the large (3 nm in length) and complex molecular structure of ciguatoxins has impeded chemists from completing their total synthesis. In this article, the full details of studies leading to the total synthesis of ciguatoxin CTX3C are provided. The key elements of the first-generation approach include O,O-acetal formation from the right and left wing fragments, conversion from O,O-acetal to O,S-acetal, a radical reaction to cyclize the G ring, a ring-closing metathesis reaction to close the F ring, and final removal of the 2-naphtylmethyl protective groups. Subsequent studies provided a second-generation total synthesis, which is more concise and results in a higher yield. Second-generation synthesis was accomplished by using a direct method of constructing the key intermediate O,S-acetal from alpha-chlorosulfide and a secondary alcohol. These syntheses ensure a practical supply of ciguatoxin for biological applications.

Thiosemicarbazones: preparation methods, synthetic applications and biological importance; Tiossemicarbazonas: metodos de obtencao, aplicacoes sinteticas e importancia biologica

Energy Technology Data Exchange (ETDEWEB)

Tenorio, Romulo P.; Goes, Alexandre J.S. [Universidade Federal de Pernambuco, Recife, PE (Brazil). Dept. de Antibioticos]. E-mail: ajsg@ufpe.br; Lima, Jose G. de; Faria, Antonio R. de; Alves, Antonio J.; Aquino, Thiago M. de [Universidade Federal de Pernambuco, Recife, PE (Brazil). Dept. de Ciencias Farmaceuticas

2005-11-15

Thiosemicarbazones are a class of compounds known by their chemical and biological properties, such as antitumor, antibacterial, antiviral and antiprotozoal activity. Their ability to form chelates with metals has great importance in their biological activities. Their synthesis is very simple, versatile and clean, usually giving high yields. They are largely employed as intermediates, in the synthesis of others compounds. This article is a survey of some of these characteristics showing their great importance to organic and medicinal chemistry. (author)

Immunomodulatory Effects of Macrolide Antibiotics - Part 1 : Biological Mechanisms

NARCIS (Netherlands)

Altenburg, J.; de Graaff, C. S.; van der Werf, T. S.; Boersma, W. G.

2011-01-01

Macrolide antibiotics are well known for their antibacterial and anti-inflammatory properties. This article provides an overview of the biological mechanisms through which macrolides exert this 'double effect'. Their antibacterial effect consists of the inhibition of bacterial protein synthesis,

Synthesis, characterization and in vivo evaluation of biocompatible ferrogels

Energy Technology Data Exchange (ETDEWEB)

Lopez-Lopez, M.T., E-mail: modesto@ugr.es [Department of Applied Physics, University of Granada, Granada (Spain); Instituto de Investigación Biosanitaria ibs.GRANADA, Granada (Spain); Rodriguez, I.A. [Instituto de Investigación Biosanitaria ibs.GRANADA, Granada (Spain); Department of Histology (Tissue Engineering Group), University of Granada, Granada (Spain); Rodriguez-Arco, L. [Department of Applied Physics, University of Granada, Granada (Spain); Instituto de Investigación Biosanitaria ibs.GRANADA, Granada (Spain); Carriel, V. [Instituto de Investigación Biosanitaria ibs.GRANADA, Granada (Spain); Department of Histology (Tissue Engineering Group), University of Granada, Granada (Spain); Bonhome-Espinosa, A.B. [Department of Applied Physics, University of Granada, Granada (Spain); Instituto de Investigación Biosanitaria ibs.GRANADA, Granada (Spain); Campos, F. [Instituto de Investigación Biosanitaria ibs.GRANADA, Granada (Spain); Department of Histology (Tissue Engineering Group), University of Granada, Granada (Spain); Zubarev, A. [Department of Mathematical Physics, Ural Federal University, Ekaterinburg (Russian Federation); Duran, J.D.G. [Department of Applied Physics, University of Granada, Granada (Spain); Instituto de Investigación Biosanitaria ibs.GRANADA, Granada (Spain)

2017-06-01

A hydrogel is a 3-D network of polymer chains in which water is the dispersion medium. Hydrogels have found extensive applications in the biomedical field due to their resemblance to living tissues. Furthermore, hydrogels can be endowed with exceptional properties by addition of synthetic materials. For example, magnetic field-sensitive gels, called ferrogels, are obtained by embedding magnetic particles in the polymer network. Novel living tissues with unique magnetic field-sensitive properties were recently prepared by 3-D cell culture in biocompatible ferrogels. This paper critically reviews the most recent progress and perspectives in their synthesis, characterization and biocompatibility evaluation. Optimization of ferrogels for this novel application requires low-density, strongly magnetic, multi-domain particles. Interestingly, the rheological properties of the resulting ferrogels in the absence of field were largely enhanced with respect to nonmagnetic hydrogels, which can only be explained by the additional cross-linking imparted by the embedded magnetic particles. Remarkably, rheological measurements under an applied magnetic field demonstrated that ferrogels presented reversibly tunable mechanical properties, which constitutes a unique advantage with respect to nonmagnetic hydrogels. In vivo evaluation of ferrogels showed good biocompatibility, with only some local inflammatory response, and no particle migration or damage to distant organs.

Solid phase synthesis and antiprotozoal evaluation of di- and trisubstituted 5'-carboxamidoadenosine analogues.