WorldWideScience

Sample records for aminonaphthoquinone mannich bases

  1. Novel aminonaphthoquinone mannich bases derived from lawsone and their copper(II) complexes: synthesis, characterization and antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Neves, Amanda P.; Barbosa, Claudia C.; Greco, Sandro J.; Vargas, Maria D. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Inst. de Quimica; Visentin, Lorenzo C. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Quimica; Pinheiro, Carlos B. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Fisica; Mangrich, Antonio S. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Centro Politecnico. Dept. de Quimica; Barbosa, Jussara P.; Costa, Gisela L. da [Instituto Oswaldo Cruz, Rio de Janeiro, RJ (Brazil)

    2009-07-01

    A series of novel Mannich bases (HL1-HL13) derived from 2-hydroxy-1,4-naphthoquinone (lawsone), substituted benzaldehydes [C{sub 6}H{sub 2}R{sup 1}R{sup 2}R{sup 3}C(O)H] and various primary amines (NH{sub 2}R{sup 4}, R{sup 4} = n-butyl, benzyl, allyl, 2-furfuryl), and their Cu{sup 2+} complexes, [Cu(L1){sub 2}]-[Cu(L13){sub 2}], have been synthesized and fully characterized by analytical and spectroscopic methods. The structures of complexes 1 (R{sup 1} R{sup 2} = R{sup 3} = H; R{sup 4} = Bu), 2 (R{sup 1} = R{sup 3} = H; R{sup 2} = NO{sub 2}; R{sup 4}= Bu) and 7 (R{sup 1} OH; R{sup 2} = R{sup 3} = H; R{sup 4}= Bu) were determined by single crystal X-ray diffraction studies. All complexes crystallize in centrosymmetric space groups, with a copper atom in the inversion centre. Two L. coordinate through the naphthalen-2-olate oxygen and secondary amine-N atoms, forming six membered chelate rings around the copper atom in a trans-N{sub 2}O{sub 2} environment; spectroscopic data confirm that the other complexes exhibit similar molecular arrangement. The antimicrobial activity of all compounds has been tested on seven different strains of bacteria: Bacillus cereus, Bacillus subtilis, Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa and Staphylococcus aureus. In general, Mannich bases were more active than complexes, HL11 (R{sup 1} = OH; R{sup 2} =H; R{sup 3} = Me; R{sup 4}= Bn) and HL13 (R{sup 1} = OH; R{sup 2} = H; R{sup 3} = Br; R{sup 4}= Bn) being the most potent inhibitors. The MIC for the most active compound HL11 against S. Coli was 20 {mu}mol L{sup -1} (8 {mu}g mL{sup -1}), better than Chloramphenicol (90 {mu}mol L{sup -1}) and well below most values reported for other naphthoquinones. (author)

  2. Mannich Bases: An Important Pharmacophore in Present Scenario

    OpenAIRE

    Bala, Suman; Sharma, Neha; Kajal, Anu; Kamboj, Sunil; Saini, Vipin

    2014-01-01

    Mannich bases are the end products of Mannich reaction and are known as beta-amino ketone carrying compounds. Mannich reaction is a carbon-carbon bond forming nucleophilic addition reaction and is a key step in synthesis of a wide variety of natural products, pharmaceuticals, and so forth. Mannich reaction is important for the construction of nitrogen containing compounds. There is a number of aminoalkyl chain bearing Mannich bases like fluoxetine, atropine, ethacrynic acid, trihexyphenidyl, ...

  3. Mannich Bases: An Important Pharmacophore in Present Scenario

    Directory of Open Access Journals (Sweden)

    Suman Bala

    2014-01-01

    Full Text Available Mannich bases are the end products of Mannich reaction and are known as beta-amino ketone carrying compounds. Mannich reaction is a carbon-carbon bond forming nucleophilic addition reaction and is a key step in synthesis of a wide variety of natural products, pharmaceuticals, and so forth. Mannich reaction is important for the construction of nitrogen containing compounds. There is a number of aminoalkyl chain bearing Mannich bases like fluoxetine, atropine, ethacrynic acid, trihexyphenidyl, and so forth with high curative value. The literature studies enlighten the fact that Mannich bases are very reactive and recognized to possess potent diverse activities like anti-inflammatory, anticancer, antifilarial, antibacterial, antifungal, anticonvulsant, anthelmintic, antitubercular, analgesic, anti-HIV, antimalarial, antipsychotic, antiviral activities and so forth. The biological activity of Mannich bases is mainly attributed to α, β-unsaturated ketone which can be generated by deamination of hydrogen atom of the amine group.

  4. Mannich bases: an important pharmacophore in present scenario.

    Science.gov (United States)

    Bala, Suman; Sharma, Neha; Kajal, Anu; Kamboj, Sunil; Saini, Vipin

    2014-01-01

    Mannich bases are the end products of Mannich reaction and are known as beta-amino ketone carrying compounds. Mannich reaction is a carbon-carbon bond forming nucleophilic addition reaction and is a key step in synthesis of a wide variety of natural products, pharmaceuticals, and so forth. Mannich reaction is important for the construction of nitrogen containing compounds. There is a number of aminoalkyl chain bearing Mannich bases like fluoxetine, atropine, ethacrynic acid, trihexyphenidyl, and so forth with high curative value. The literature studies enlighten the fact that Mannich bases are very reactive and recognized to possess potent diverse activities like anti-inflammatory, anticancer, antifilarial, antibacterial, antifungal, anticonvulsant, anthelmintic, antitubercular, analgesic, anti-HIV, antimalarial, antipsychotic, antiviral activities and so forth. The biological activity of Mannich bases is mainly attributed to α, β-unsaturated ketone which can be generated by deamination of hydrogen atom of the amine group.

  5. Biosynthesis of some Mannich bases

    Directory of Open Access Journals (Sweden)

    Bruna S. D. R. Aranha

    2012-06-01

    Full Text Available The Mannich reaction is extremely useful to form molecules that contain nitrogen groups. Currently, there is a great interest turned to this class of compounds due to its biological properties. The recent literature reports that the utilization of enzymes can be an adequate methodology on this type of reaction. According to the exposed above and with the intention of synthesizing the -aminoketones, some catalysts like Chymosin and also some microorganisms such as Saccharomyces cerevisiae, (sourdough bread and Lactobacilos (ATCC 90827LA10N19.10-E.U.A were applied. These reactions were carried out by using water as solvent at room temperature excelling for the Green Chemistry principles. Figure 1 shows the reaction scheme involving 1 eq.mol of aniline, 1,3 eq.mol of formaldehyde, 10 ml of water and 0,25g of the catalyst during four days. The reaction furnished satisfactory yields which are in accordance with the literature data.

  6. A new Mannich base and its transition metal (II) complexes ...

    Indian Academy of Sciences (India)

    Unknown

    some metal complexes of this type of Mannich base and investigate its bonding characteristics. We herein report a new Mannich base, N-(1-morpholinoben- zyl) semicarbazide formed by the three-component condensation, containing active hydrogen on nitro- gen (morpholine), benzaldehyde and semicarbazide.

  7. Mannich bases in medicinal chemistry and drug design.

    Science.gov (United States)

    Roman, Gheorghe

    2015-01-07

    The biological activity of Mannich bases, a structurally heterogeneous class of chemical compounds that are generated from various substrates through the introduction of an aminomethyl function by means of the Mannich reaction, is surveyed, with emphasis on the relationship between structure and biological activity. The review covers extensively the literature reports that have disclosed Mannich bases as anticancer and cytotoxic agents, or compounds with potential antibacterial and antifungal activity in the last decade. The most relevant studies on the activity of Mannich bases as antimycobacterial agents, antimalarials, or antiviral candidates have been included as well. The review contains also a thorough coverage of anticonvulsant, anti-inflammatory, analgesic and antioxidant activities of Mannich bases. In addition, several minor biological activities of Mannich bases, such as their ability to regulate blood pressure or inhibit platelet aggregation, their antiparasitic and anti-ulcer effects, as well as their use as agents for the treatment of mental disorders have been presented. The review gives in the end a brief overview of the potential of Mannich bases as inhibitors of various enzymes or ligands for several receptors. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  8. Synthesis and Reactivity of Some Mannich Bases. VI. New Arylamine Mannich Bases Derived From 2-Hydroxy-5-Methylacetophenone

    OpenAIRE

    ROMAN, Gheorghe; NANU, Diana

    2000-01-01

    The amine exchange reaction has been applied for obtaining a new series of arylamine Mannich bases from variously substituted aromatic amines and 3-(dimethylamino)-1-(2'-hydroxy-5'-methylphenyl) propan-1-one. The structures of the newly synthesised Mannich bases have been investigated by IR, 1H- and 13C-NMR and shown to be in good agreement with the proposed ones.

  9. Stereoselective bioreduction of someMannich bases

    Directory of Open Access Journals (Sweden)

    Bruna S. D. R. Aranha

    2012-06-01

    Full Text Available The chemic reaction that happen on the live organism (plants, superior animals and microorganisms produce various chiral substances such as pheromones, antibiotics and others. After the eighties, with the break of the dogma referent to the enzymatic utilization only in aqueous medias, diverse enzyme application were revealed in other reaction medias, what allowed new studies turned to enzymatic application in organic chemistry. Such studies revealed that these biocatalysts presented high selectivity in these medias, no only about to the chemoselectivity but especially to the enantioselectivity. According to what was exposed, this work aimed to execute the bioreduction of some Mannich bases using the microorganism Saccharomyces cerevisiae (sourdough bread. Scheme 1 shows the reaction scheme involving 1 eq.mol of the b-aminocarbonilated product, 10 mL of   the suitable solvent and 0,5g of the biocatalys during four days at room temperature. These reactions presented satisfactory yields, which are in accordance with the literature.

  10. Synthesis and reactivity of some Mannich bases. VIII. Studies on several Mannich bases derived from ortho-hidroxyacetophenones and their conversion into oximino derivatives

    Directory of Open Access Journals (Sweden)

    BOGDAN COMANITA

    2001-01-01

    Full Text Available The synthesis of several Mannich bases resulting from the reaction of 2-hydroxy-4-methylacetophenone with paraformaldehyde and secondary amines is reported. Another series of products was obtained from N,N-dimethyl substituted Mannich bases by replacing the amino group with pyrrolidine. Most of the Mannich bases were transformed into oximes by treatment with hydroxylamine hydrochloride in 10 % NaOH.

  11. Synthesis of novel ferrocenyl Mannich bases and their antibacterial activities

    Science.gov (United States)

    Liu, Yuting; Xin, Hong; Yin, Jingyi; Yin, Dawei; Yang, Zijiang; Li, Jie

    2018-04-01

    In this work, a series of Mannich bases bearing ferrocenyl groups were synthesized via Mannich reactions. The effects of different conditions on the reaction were explored, and the newly synthesized compounds were well characterized by NMR and FT-IR. All compounds have been screened for in vitro antibacterial and antifungal, and the compounds 1-ferrocenyl-3-phenyl-3-(m-nitrophenylamino)-1-acetone (2f) and 1-ferrocenyl-3-phenyl-3-(p-nitrophenylamino)-1-acetone (2g) were shown to be significant activity against all the tested bacterial strains, such as Staphylococcus aureus, Streptococcus, Actinomycete, Escherichia coli, Saccharomyces cerevisiae.

  12. Synthesis and antiproliferative activity of various novel indole Mannich bases

    Directory of Open Access Journals (Sweden)

    Mardia T El Sayed

    2015-11-01

    Full Text Available Various secondary and primary amines were converted into bis-indolyl Mannich bases with good to excellent yields via double condensation reactions with indole and glutaraldehyde. The expected bis-indolyl Mannich bases (2, 3 and 4 were formed by using piperazinehexahydrate and 4,4′-trimethylenedipiperidine. Whereas, the use of primary amines, phenylhydrazine, amino acids and primary diamine produced the corresponding bis-indolyl-1,2,6-trisubstituted pipridines (5a-e and indolyl-quinolizine (6 and dibis-indolyl-1,2,6-trisubstituted pipridines (7. All analytical and spectral data of these bis-indolyl Mannich bases have been determined. Six of the synthesized bis-indolyl Mannich bases have been subjected for antiproliferative activity screening at National Cancer Institute (NCI, Egypt, towards three human tumor cell lines representing different tumor types: breast adenocarcinoma cell (MCF-7, non-small lung cancer cell (NCI-H460, and central nervous system (CNS cancer cell (SF-268. Compound (4 indicated the best and highest inhibitory effect against all three tested tumor cell lines with inhibition of 50% concentration (IC50 for MCF-7 (0.08µmol/L, NCI-H460(0.05µmol/L and SF-268 (0.01 µmol/L.

  13. Synthesis and Antiproliferative Activity of Thioxoflavones Mannich Base Derivatives.

    Science.gov (United States)

    Li, Wei; Li, Xueli; Liu, Manhui; Wang, Qiuan

    2017-07-01

    Two series of 12 novel thioxoflavones Mannich base derivatives 5a-f and 6a-f were synthesized via Mannich reaction of 4',7-dimethoxy-5-hydroxyflavothione (3) or 3',4',7-trimethoxy-5-hydroxyflavothione (4) with appropriate aliphatic amines or alicyclic amines and formaldehyde. Thioxoflavones 3 and 4 were prepared from 4',7-dimethoxy-5-hydroxyflavone (1) and 3',4',7-trimethoxy-5-hydroxyflavone (2) with Lawesson's reagent, respectively. Their antiproliferative activities in vitro were evaluated on a panel of three human cell lines (HeLa, HCC1954, and SK-OV-3) by CCK-8 assay. The results showed that most of the thioxoflavones and their Mannich base derivatives exhibited potential antiproliferative activities on the tested cancer cell lines, with IC 50 values ranging from 9.16 to 55.50 μM. In particular, thioxoflavone 4 and the thioxoflavone Mannich base derivatives 5a and 5d showed the best antiproliferative activity on all three human cancer cell lines; they are promising candidates worthy of further development. The structures of all synthesized compounds were confirmed by 1 H NMR, 13 C NMR, IR, and MS techniques. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. NUCLEOPHILIC SUBSTITUTION REACTION OF CYANIDE AND METHOXYDE IONS TO QUATERNARY MANNICH BASE FROM VANILLIN

    OpenAIRE

    Bambang Purwono; Estiana R. P. Daruningsih

    2010-01-01

    The nucleophilic substitution reaction to quaternary Mannich base from vanillin has been investigated. Mannich reaction to vanillin was carried out by refluxing mixture of vanillin, formaldehyde and dimethyl amine. Quaternary ammonium halide salt was obtained from reaction of Mannich vanillin base with methyl iodide in THF solvents and yielded 93.28 %. Nucleophilic substituion to the halide salts with cyanide nucleophile produced 4-hidroxy-3-methoxy-5-(cyano)methylbenzaldehyde in 54.39% yiel...

  15. NUCHLEOPHILIC SUBSTITUTION REACTION OF CYANIDE AND METHOXYDE IONS TO QUATERNARY MANNICH BASE FROM VANILLIN

    OpenAIRE

    Purwono, Bambang; Daruningsih, Estiana E.P

    2010-01-01

    The nucleophilic substitution reaction to quaternary Mannich base from vanillin has been investigated. Mannich reaction to vanillin was carried out by refluxing mixture of vanillin, formaldehyde and dimethyl amine. Quaternary ammonium halide salt was obtained from reaction of Mannich vanillin base with methyl iodide in THF solvents and yielded  93.28%. Nucleophilic substituion to the halide salts with cyanide nucleophile produced 4-hidroxy-3-methoxy-5-(cyano)methylbenzaldehyde in 54.39% yield...

  16. Diesel fuel containing polyalkylene amine and Mannich base

    Energy Technology Data Exchange (ETDEWEB)

    Harle, O.L.

    1979-06-21

    The fuel composition for diesel engines is characterized in that it contains a hydrocarbon with a boiling range of 120-455/sup 0/C as main component and as additive 5 to 300 ppm of a polyakylene amine, as well as 5 to 300 ppm of the reaction product of an alkyl phenol, an aldehyde and an amine (Mannich base). This additive composition increases the oxidation and thermal stability of the fuel.

  17. NUCLEOPHILIC SUBSTITUTION REACTION OF CYANIDE AND METHOXYDE IONS TO QUATERNARY MANNICH BASE FROM VANILLIN

    Directory of Open Access Journals (Sweden)

    Bambang Purwono

    2010-06-01

    Full Text Available The nucleophilic substitution reaction to quaternary Mannich base from vanillin has been investigated. Mannich reaction to vanillin was carried out by refluxing mixture of vanillin, formaldehyde and dimethyl amine. Quaternary ammonium halide salt was obtained from reaction of Mannich vanillin base with methyl iodide in THF solvents and yielded 93.28 %. Nucleophilic substituion to the halide salts with cyanide nucleophile produced 4-hidroxy-3-methoxy-5-(cyanomethylbenzaldehyde in 54.39% yield. Reaction with methoxyde ion yielded 4-hydroxy- 3-methoxy-5-(methoxy -methylbenzaldehyde in 67.80% yield. The nucleophilic substitution reaction showed that trimethylamino substituent of quaternary Mannich base can act as a good leaving group on nucleophilic substitution reactions. Keywords: Mannich reaction, vanillin, nucleophilic substitution

  18. NUCHLEOPHILIC SUBSTITUTION REACTION OF CYANIDE AND METHOXYDE IONS TO QUATERNARY MANNICH BASE FROM VANILLIN

    Directory of Open Access Journals (Sweden)

    Bambang Purwono

    2010-06-01

    Full Text Available The nucleophilic substitution reaction to quaternary Mannich base from vanillin has been investigated. Mannich reaction to vanillin was carried out by refluxing mixture of vanillin, formaldehyde and dimethyl amine. Quaternary ammonium halide salt was obtained from reaction of Mannich vanillin base with methyl iodide in THF solvents and yielded  93.28%. Nucleophilic substituion to the halide salts with cyanide nucleophile produced 4-hidroxy-3-methoxy-5-(cyanomethylbenzaldehyde in 54.39% yield, with methoxyde ion obtained  4-hidroxy- 3-methoxy-5-(methoxy-methyl-benzaldehide in 67.80% yield. The nucleophilic substitution reaction showed that substituen of trimethylamino quaternary Mannich base can act as a good leaving on nucleophilic reaction substitutions.   Keywords: Mannich Reaction, Vanillin, nucleophilic substitution.

  19. Green chemistry approach to the synthesis of potentially bioactive aminobenzylated Mannich bases through active hydrogen compounds

    Directory of Open Access Journals (Sweden)

    S. L. VASOYA

    2005-10-01

    Full Text Available An efficient and high yield method for the synthesis of aminobenzylated Mannich bases is described. The synthesis occurs in aqueous medium at 0 ºC. The compounds show moderate antitubercular and antimicrobial activities.

  20. Regioselective reaction: synthesis and pharmacological study of Mannich bases containing ibuprofen moiety.

    Science.gov (United States)

    Sujith, K V; Rao, Jyothi N; Shetty, Prashanth; Kalluraya, Balakrishna

    2009-09-01

    A series of 4-[(4-aryl)methylidene]amino-2-(substituted-4-ylmethyl)-5-{1-[4-(2-methylpropyl)phenyl]ethyl}-2,4-dihydro-3H-1,2,4-triazole-3-thione (6) were synthesized from an arylpropionic acid namely, ibuprofen by a three-component Mannich reaction. Aminomethylation of 4-[(4-aryl)methylidene]amino-5-{1-[4-(2-methylpropyl)phenyl] ethyl}-4H-1,2,4-triazole-3-thiol (5) with formaldehyde and a secondary amine furnished this novel series of Mannich bases (6). Both Schiff bases (5) and Mannich bases (6) were well characterized on the basis of IR, NMR, mass spectral data and elemental analysis. They were screened for their anti-inflammatory, analgesic, antibacterial and antifungal activities. Some of the Mannich bases (6) carrying morpholino and N-methylpiperazino residues were found to be promising anti-inflammatory and analgesic agents.

  1. Synthesis, spectroscopic characterization and antibacterial screening of novel Mannich bases of Ganciclovir

    Directory of Open Access Journals (Sweden)

    Sheela Joshi

    2017-02-01

    Full Text Available Biologically active Mannich bases with heteroaromatic ring system of substituted guanine derivative (2-amino-9 [{(1,3 di hydroxy propane-2yl oxy} methyl] 6-9 dihydro-3H-purine-6-one (ganciclovir, have been synthesized via Mannich reaction. The aminomethylation of ganciclovir with various biologically potent sulphonamides was carried out and then characterized by elemental analysis and spectral studies – UV, IR, 1H NMR, powder X-ray diffraction and Scanning Electron Microscopy. The compounds were screened for their antibacterial activity against various pathogenic bacteria at varying concentrations. The antibacterial activity of derived Mannich bases was compared with parent sulphonamides. The toxicity of synthesized Mannich bases was ascertained by LD50 test.

  2. Heterocycles 38. Biocatalytic Synthesis of New Heterocyclic Mannich Bases and Derivatives

    Directory of Open Access Journals (Sweden)

    Denisa Leonte

    2015-07-01

    Full Text Available This paper describes the biocatalytic synthesis of new Mannich bases containing various heterocyclic rings (thiazole, furane, thiophene, pyridine by applying the lipase catalyzed trimolecular condensation of the corresponding heterocyclic aldehydes with acetone and primary aromatic amines, in mild and eco-friendly reaction conditions. The obtained Mannich bases were acylated to their corresponding N-acetyl derivatives. All compounds were characterized by 1H-NMR, 13C-NMR and MS spectrometry.

  3. Heterocycles 38. Biocatalytic Synthesis of New Heterocyclic Mannich Bases and Derivatives.

    Science.gov (United States)

    Leonte, Denisa; Bencze, László Csaba; Paizs, Csaba; Irimie, Florin Dan; Zaharia, Valentin

    2015-07-06

    This paper describes the biocatalytic synthesis of new Mannich bases containing various heterocyclic rings (thiazole, furane, thiophene, pyridine) by applying the lipase catalyzed trimolecular condensation of the corresponding heterocyclic aldehydes with acetone and primary aromatic amines, in mild and eco-friendly reaction conditions. The obtained Mannich bases were acylated to their corresponding N-acetyl derivatives. All compounds were characterized by 1H-NMR, 13C-NMR and MS spectrometry.

  4. Efavirenz Mannich bases: synthesis, anti-HIV and antitubercular activities.

    Science.gov (United States)

    Sriram, Dharmarajan; Banerjee, Debjani; Yogeeswari, Perumal

    2009-02-01

    A series of efavirenz Mannich bases has been synthesized by reacting efavirenz, formaldehyde, and various aryl substituted piperazines using microwave irradiation (yield 35-88%). The synthesized compounds were evaluated for in-vitro anti-HIV and antimycobacterial activities. The in-vitro antiretroviral activities indicated that compound 7-(4-((6-chloro-4-(2-cyclopropylethynyl)-4-(trifluoromethyl)-2-oxo-2H-benzo[d] [1,3]oxazin-1 (4H)-yl)methyl)-3-methylpiperazin-l -yl)-1-cyclopropyl-6-fluoro-l,4-dihydro-8-methoxy-4-oxoquinoline-3-carboxylic acid (4i) was equipotent to efavirenz with EC(50) of 2.4 nM. Compound 4i also inhibited M. tuberculosis with minimum inhibitory concentration of 0.2 microg/mL.

  5. Reaction of the condensation of alkylphenols with formaldehyde and ammonia. [Mannich base

    Energy Technology Data Exchange (ETDEWEB)

    Sopkina, A.K.; Gordash, Iu.T.; Grechko, A.N.; Marusiak, O.V.; Sukhoverkhov, V.D.; Zriakov, I.N.

    1980-01-01

    The Mannich base, which is produced by the condensation of alkylphenols with formaldehyde and ammonia, is used as an additive or as an intermediate product in the production of additives. With condensation according to Mannich, the yield of the bases depends on the structure of the original alkylphenol and the conditions of the condensations. It is shown, that with the use of monoalkylphenols, having linear or a ramified radical, it is possible to produces practically a complete conversion of alkylphenols. As a rule, the yield of the Mannich bases in these conditions is greater than 80%. For the dialkylphenols, the yield of the Mannich bases in analogous conditions does not exceed 50%. The attempt to find the optimal conditions of the condensation reaction according to Mannich with the help of the method of nonlinear programming showed, that the yield of the Mannich bases is affected not only by the concentration, the duration of the reaction, and temperature, but also more complex factors of the paired effect of the concentration, the duration of the reaction, concentration and temperature.

  6. Antibacterial activity of Mannich bases derived from 2-naphthols, aromatic aldehydes and secondary aliphatic amines.

    Science.gov (United States)

    Roman, Gheorghe; Năstasă, Valentin; Bostănaru, Andra-Cristina; Mareş, Mihai

    2016-05-15

    A small library of 1-aminoalkyl 2-naphthols has been synthesized through the direct Mannich reaction of 2-naphthols with (hetero)aromatic aldehydes and secondary amines. All of the Mannich bases having a thiophen-2-yl ring in their structure had good activity against Gram-positive bacteria, irrespective of the nature of the amino moiety. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Liquid hydrocarbon fuels containing high molecular weight Mannich bases

    Energy Technology Data Exchange (ETDEWEB)

    Udelhofen, J.H.; Watson, R.W.

    1980-11-04

    Reaction products obtained from the Mannich condensation of high molecular weight alkyl-substituted hydroxy aromatic compounds, amines and aldehydes provide improved detergency in liquid hydrocarbon fuels. Optionally, a non-volatile hydrocarbon carrier fluid may be included.

  8. Synthesis and antiproliferative activity of imidazo[1,2-a]pyrimidine Mannich bases.

    Science.gov (United States)

    Aeluri, Raghunath; Alla, Manjula; Polepalli, Sowjanya; Jain, Nishant

    2015-07-15

    A series of imidazo[1,2-a]pyrimidine Mannich bases were designed, synthesized in two phases. Mannich bases were obtained by one pot three component condensation of imidazo[1,2-a]pyrimidine with secondary amine or piperazine and excess of formaldehyde solution in methanol. The synthesized Mannich bases were screened for in vitro growth inhibition against a panel of 3 different human cancer cell lines. Most of the synthesized compounds exhibited antiproliferative activity with GI50 values ranging from 0.01 to 79.4 μM. Compounds 5e, 6b and 7k were found to be effective inhibitors of growth of all cell lines, with GI50 values similar to that of standard drug. The structure and activity relationship has been disclosed. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  9. AN EXPLORATION ON THE SYNTHESIS AND BIO-APPLICATIONS OF DERIVATIVES OF HETEROCYCLIC MANNICH BASES

    Directory of Open Access Journals (Sweden)

    P. S. Manjula

    2016-01-01

    Full Text Available The Mannich reaction is a three-component reaction of an aldehyde, a primary or secondary amine and a ketone which is one of the most powerful C-C bond forming reactions in organic synthesis. It leads to β-amino carbonyl compounds, which are useful for the syntheses of nitrogen containing compounds, such as natural products and medicinally relevant compounds. The versatility and potential of these compounds to introduce both functional and structural diversity using the Mannich reaction have stimulated the creativity of chemists. 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.

  10. Phenolic-containing mannich base reaction products and fuel compositions containing same

    Energy Technology Data Exchange (ETDEWEB)

    Chibnik, S.

    1989-02-21

    This patent describes a product of reaction suitable for use as a liquid hydrocarbyl fuel additive made by reacting a performed Mannich base with a reactive compound selected from hydrocarbyl thiols having at least one reactive hydrogen, the reaction being carried out with an equivalent amount of Mannich Base, or with a molar ratio varying 1 to 1 to about 2 to 1 of Mannich Base to thiol at temperatures varying from about 25/sup 0/ to about 250/sup 0/C. the Mannich base having been prepared from (1) a phenol, (2) a C/sub 1/-C/sub 8/ alkyl aldehyde and (3) an amine having a lower boiling point than that of the reactive thiol, the phenol having the following generalized structural formula: where R/sup 2/ and R/sup 3/ are the same or different and are hydrogen or C/sub 1/ to about C/sub 18/ alkyl or tertiary alkyl and R/sup 4/ is H or C/sub 1/ to about C/sub 30/ hydrocarbyl.

  11. Liquid microchromatographic analysis of intermediate and final products during the production process of highly molecular Mannich base additives

    Energy Technology Data Exchange (ETDEWEB)

    Zakupra, V.A.; Petrenko, L.M.; Popovich, T.D.

    1982-01-01

    It was shown that a single separation provides data on the content: highly molecular Mannich base parts (for one of the intermediate products and the resultant additive -- with added boric acid), polyisobutylene in a mix with diluting oil and polyisobutylphenol (separately or together) low molecular Mannich base parts (in the latter also concentrated are traces of fatty acids, boric acid and polyethylenepolyamins that did not enter the reaction). To identify structures of extracted Mannich bases and other substances infra-red spectroscopy and ebullioscopy, microanalytic determination of boron and nitrogen were utilized. A more rapid technique of liquid microchromatorgraphy is offered, to be used to monitor additive production.

  12. NMR study of the preparation of 6 {alpha}, 7 {beta}-dihydroxyvouacapan-17 beta-oic acid mannich base derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Flavio Jose Leite dos; Pilo-Veloso, Dorila [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte (Brazil). Inst. de Ciencias Exatas. Dept. Quimica]. E-mail: dorila@zeus.qui.ufmg.br; Ferreira-Alves, Dalton L. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte (Brazil). Inst. de Ciencias Biologicas. Dept. de Farmacologia

    2007-07-01

    This work presents four new Mannich base compounds obtained by the Mannich reaction of a {delta}-keto-lactone derivative of 6{alpha}, 7{beta}-dihydroxyvouacapan- 17{beta}-oic acid, a furano diterpene isolated from the hexane extract of Pterodon polygalaeflorus Benth fruits, which shows anti-inflammatory and analgesic activities. The use of 1D and 2D NMR (COSY, DEPT-135, HMBC, HMQC) spectroscopy made it possible to characterize the new compounds. (author)

  13. Regioselective reaction: synthesis, characterization and pharmacological activity of some new Mannich and Schiff bases containing sydnone.

    Science.gov (United States)

    Nithinchandra; Kalluraya, B; Aamir, S; Shabaraya, A R

    2012-08-01

    A novel series of 1-substituted aminomethyl-3-[1-(4-isobutylphenyl)ethyl]-4-(3-aryl-4-sydnonylidene) amino-1,2,4-triazol-5-thiones (9), was prepared from the 3-[1-(4-isobutylphenyl)ethyl]-4-(3-aryl-4-sydnonylidene) amino 5-mercapto-1,2,4-triazoles (8) by aminomethylation with formaldehyde and secondary amine. The structures of Schiff bases (8) and Mannich bases (9) were characterized on the basis of IR, NMR, mass spectra1 data and elemental analysis. The newly synthesized compounds were screened for their anti-inflammatory and analgesic activities. Mannich bases (9) carrying piperidine and morpholine residues showed promising anti-inflammatory and analgesic activity. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  14. Trimerization catalysis of phenylisocyanate in the presence of phenolic mannich bases

    Energy Technology Data Exchange (ETDEWEB)

    Selivanov, A.V.; Zenitova, L.A.; Bakirova, I.N.; Kirpichnikov, P.A.

    1988-11-01

    The kinetics of the cyclic trimerization of phenylisocyanate in the presence of phenolic Mannich bases have been studied by IR spectroscopy; a catalysis mechanism for the reaction is proposed. It was found that in order for trimerization to occur the catalyst molecule must contain both a hydroxyl group and a tertiary nitrogen atom, which leads to reaction at the OH group of the catalyst and its conversion via a urethane derivative to an allophanate; the latter species undergoes tautomeric rearrangement to a bipolar ion, which is the actual catalysis site. The effects of the number of aminomethyl, hydroxyl, and other electron-donating and electron-withdrawing substituents on the structure of Mannich bases have also been investigated.

  15. Phenolic-containing Mannich base reaction products and fuel compositions containing same

    Energy Technology Data Exchange (ETDEWEB)

    Chibnik, S.

    1990-01-01

    This patent describes a composition. It comprises: a major amount of a liquid hydrocarbyl fuel normally susceptible to oxidation and a minor antioxidant amount of an additive product prepared by reacting a preformed Mannich base derived from a phenol, a C{sub 1}-C{sub 8} alkyl aldehyde and a low boiling amine, and a reactive compound having at least one reactive hydrogen selected from reactive hydrocarbyl amines.

  16. 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.

  17. Novel Mannich-bases as Potential Anticonvulsants: Syntheses, Characterization and Biological Evaluation.

    Science.gov (United States)

    Keshari, Amit K; Tewari, Aseem; Verma, Shweta S; Saraf, Shailendra K

    2017-01-01

    Mannich bases are known to be an important pharmacophore or bioactive leads in the synthesis of various potential agents that have a variety of therapeutic activities like anticancer, antipsychotic, anticonvulsant, antimalarial, anti-inflammatory, antibacterial and so forth. Thus, in the present research, conjugation of moieties like 1,5-benzoxazepines and 1,5-benzothiazepines with secondary amines like piperazine, methyl piperazine and morpholine was carried out in a Mannich base with an anticipation of good anticonvulsant activity. Synthesis, characterization, structure activity relationship and anticonvulsant activity of the Mannich bases of 1,5-benzothiazepine and 1,5-benzoxazepine derivatives. All the derivatives were synthesized in three steps. In the first step, substituted 4-hydroxy chalconylbenzene was synthesized by the reaction of 4-hydroxyacetophenone and substituted benzaldehyde, in the presence of potassium hydroxide. In the second step, 2,3-dihydro- 1,5- benzothiazepines and 2,3-dihydro-1,5-benzoxazepines were synthesized by the reaction of 2- thio/aminophenol with chalcones in the presence of glacial acetic acid. In the third step, these compounds finally underwent Mannich reaction with different secondary amines to the respective title compounds. All the synthesized derivatives were characterised and evaluated for anticonvulsant activity using MES (Maximal Electroshock Induced Seizure) and INH (Isoniazide Induced Convulsion) models. The synthesized derivatives were found to be more active in the MES model than INH model, with phenytoin and diazepam being the standards respectively. Accordingly, the mode of action of the synthesized compounds may be similar to phenytoin. The methyl piperazine containing compound, at a dose of 30 mg/kg., was found to be the most active and promising compound in the series. The benzothiazepine derivatives showed better anticonvulsant activity than the benzoxazepines derivatives. Copyright© Bentham Science Publishers

  18. A Strategy for Nonmigrating Plasticized PVC Modified with Mannich base of Waste Cooking Oil Methyl Ester.

    Science.gov (United States)

    Jia, Puyou; Zhang, Meng; Hu, Lihong; Song, Fei; Feng, Guodong; Zhou, Yonghong

    2018-01-25

    The waste cooking oil (WCO) production from the catering industry and food processing industry causes serious environmental, economic and social problems. However, WCO can be used for the preparation of fine chemicals such as internal plasticizer. With this aim, this work is focused on preparing internal plasticizer by using WCO and determining technical viability of non-migration poly (vinyl chloride) (PVC) materials. The mannich base of waste cooking oil methyl ester (WCOME) was synthesized from WCO via esterification, interesterification and mannich reaction, which was used to produce self-plasticization PVC materials as an internal plasticizer. The results showed that the PVC was plasticized effectively. Self-plasticization PVC films showed no migration in n-hexane, but 15.7% of dioctyl phthalate (DOP) leached from DOP/PVC(50/50) system into n-hexane. These findings transformed the traditional plastic processing technology and obtained cleaner production of no migration plasticizer from WCO.

  19. Novel Mannich bases bearing pyrazolone moiety. Synthesis, characterization and electrochemical studies

    Directory of Open Access Journals (Sweden)

    KRISHNA NAIK

    2013-04-01

    Full Text Available The present investigation describes a series of new {4-[3-Methyl-5-oxo-4-(4|-substituted phenyl hydrazono-4,5-dihydro-pyrazol-1-yl]-phenoxy}-acetic acid (2-oxo-1-piperidine-1-ylmethyl-1,2-dihydro–indol-3-ylidene-hydrazides synthesized by the Mannich reaction of {4-[3-Methyl-5-oxo-4-(4|-substituted phenyl hydrazono-4,5-dihydro-pyrazol-1-yl]-phenoxy}-acetic acid (2-oxo-1,2-dihydro-indol-3-ylidene-hydrazide with aqueous formaldehyde and a solution of piperidine in dimethylformamide. These novel Mannich bases were characterized by elemental analysis, IR, 1H NMR and mass spectral data. Electrochemical behavior of these compounds were studied by two techniques namely polarography and cyclic voltammetry. The results from both the techniques were compared and the reduction mechanism in acidic as well as basic medium was proposed.

  20. Structural studies on Mannich bases of 2-Hydroxy-3,4,5,6-tetrachlorobenzene. An UV, IR, NMR and DFT study. A mini-review

    DEFF Research Database (Denmark)

    Hansen, Poul Erik; Spanget-Larsen, Jens

    2016-01-01

    Mannich bases of 2-Hydroxy-3,4,5,6-tetrachlorobenzene are chosen as an exemplary case for tautomeric Mannich bases. Molecular structures are calculated. OH stretching frequencies are rationalized based on DFT calculations. Intrinsic deuterium isotope effects on 13C chemical shifts in the M-form a...

  1. Mannich reaction: A versatile and convenient approach to bioactive ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 125; Issue 3. Mannich ... Mannich reaction; Mannich bases; bioactive molecules; antimalarial; antitumour; antitubercular. Abstract. This review gives an insight into the recent applications of Mannich reaction and its variants in the construction of bioactive molecules.

  2. Synthesis and evaluation of novel triazoles and mannich bases functionalized 1,4-dihydropyridine as angiotensin converting enzyme (ACE) inhibitors.

    Science.gov (United States)

    Kumbhare, Ravindra M; Kosurkar, Umesh B; Bagul, Pankaj K; Kanwal, Abhinav; Appalanaidu, K; Dadmal, Tulshiram L; Banerjee, Sanjay Kumar

    2014-11-01

    A series of novel diethyl 2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate embedded triazole and mannich bases were synthesized, and evaluated for their angiotensin converting enzyme (ACE) inhibitory activity. Screening of above synthesized compounds for ACE inhibition showed that triazoles functionalized compounds have better ACE inhibitory activity compared to that of mannich bases analogues. Among all triazoles we found 6 h, 6 i and 6 j to have good ACE inhibition activity with IC50 values 0.713 μM, 0.409 μM and 0.653 μM, respectively. Among mannich bases series compounds, only 7c resulted as most active ACE inhibitor with IC50 value of 0.928 μM. Copyright © 2014. Published by Elsevier Ltd.

  3. Synthesis and in-vitro cytotoxicity evaluation of gatifloxacin Mannich bases.

    Science.gov (United States)

    Yogeeswari, Perumal; Sriram, Dharmarajan; Kavya, Ramkumar; Tiwari, Sonali

    2005-10-01

    Mannich bases of gatifloxacin were synthesized by reacting them with formaldehyde and several isatin derivatives. Their chemical structures have been confirmed by means of their IR, 1H-NMR data and by elemental analysis. The compounds were tested in-vitro against a panel of 58 human tumour cell lines derived from nine neoplastic diseases. Among them compound 1-cyclopropyl-6-fluoro-8-methoxy-1,4-dihydro-4-oxo-7[[N4-(3'-sulphadoximino)-1'-(5-bromoisatinyl) methyl]-3-methyl N1-piperazinyl]-3-quinoline carboxylic acid (6) emerged as a potent anticancer agent being more active than standard DNA topoisomerase II inhibitor, etoposide against 30 cancer cell lines.

  4. Direct Mannich-Type Reactions Promoted by Frustrated Lewis Acid/Brønsted Base Catalysts.

    Science.gov (United States)

    Chan, Jessica Z; Yao, Wenzhi; Hastings, Brian T; Lok, Charles K; Wasa, Masayuki

    2016-10-24

    Direct Mannich-type reactions that afford both α- and β-amino esters by the reaction of a broad range of carbonyl compounds and aldimines are disclosed. The transformation is promoted by a sterically frustrated Lewis acid/Brønsted base pair, which is proposed to operate cooperatively: Within the catalyst complex, an enolate is generated that then reacts with a hydrogen-bond-activated imine. Noncovalent interactions between reactants and the catalyst provide selectivity and new opportunities for future catalyst design. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Synthesis and antiproliferative activity of pterostilbene and 3′-methoxy pterostilbene Mannich base derivatives against Hela cells.

    Science.gov (United States)

    Liu, Chongyang; Dong, Linpei; Wang, Shengchun; Wang, Qiuan

    2015-11-01

    Fourteen novel pterostilbene (1) and [Formula: see text]-methoxy pterostilbene (2) Mannich base derivatives (3-16) were synthesized via the microwave-assisted Mannich reaction of 1 or 2 with various secondary amines and formaldehyde. The regioselectivity of the reaction occurred preferentially at [Formula: see text] position of the B-ring of stilbene. The biological testing results showed that all the target compounds exhibit antiproliferative activity against Hela cells from [Formula: see text]-[Formula: see text]. Compounds 1-3, 7, 11-13, and 16 displayed higher (lower [Formula: see text] values) activity than the positive control cisplatin [Formula: see text].

  6. Synthesis, characterisation and evaluation of N-mannich bases of 2-substituted Benzimidazole derivatives

    Science.gov (United States)

    Vinoth Kumar, Sekar; Subramanian, Mohan Raj; Chinnaiyan, Santhosh Kumar

    2013-01-01

    Rationale Benzimidazoles and its derivatives represent one of the mainly biological active classes of literature. Aim In this present study aimed to synthesize N-mannich bases derivatives compounds bearing of 2-substituted benzimidazole moiety, in order to investigate their possible biological activity. Method Benzimidazole compounds were prepared from the condensation reaction between ortho phenylene diamine and various acids. Mannich base of newly synthesized Benzimidazole derivatives were synthesized from 2-substituted Benzimidazoles by reacting with secondary amines. The purity of the compounds was ascertained by melting point (m.p) and thin layer chromatography (TLC). Structures of the synthesized compounds were elucidated by spectral data. Antimicrobial assay was performed by microbroth dilution method. Bacterial genomic DNA cleavage was assessed by Agarose gel electrophoresis. Toxicity of the most effective compounds was studied by Brine-shrimp lethality assay. Result Among the synthesized compounds, compound 5E (a) and (b) was establish to be the most potent against all tested microorganisms. This two compounds exhibited complete bacterial DNA cleavage and non-toxic. Conclusion These results suggest that it an interesting compound compared to the current therapeutic agents and are considered to investigate further for the same. PMID:24563595

  7. Synthesis of some Mannich bases of 1-cyclohexylidene-N(1,2-dihydro-2-oxo-3H-indol-3-ylidene) thiosemicarbazones and their antibacterial activity.

    Science.gov (United States)

    Gupta, R P; Narayana, N L

    1997-02-01

    Some Mannich bases of 1-cyclohexylidene-N(1,2-dihydro-2-oxo-3H-indol-3- ylidene) thiosemicarbazones have been prepared by employing formaldehyde and morpholine and piperidine as secondary amines. These Mannich bases have been characterised on the basis of different physico chemical evidences. Like some alkaloids, they also form reineckate complexes which serve for their estimation. Antibacterial activity of the synthesised Mannich bases has been studied by employing nine bacterial strains. Chloro group at position 5 broadened the spectrum of activity. Compounds with piperidine showed better activity than the compounds with morpholine, against almost all the organisms used (except 1 or 2 occasions).

  8. Synthesis of Icaritin and β-anhydroicaritin Mannich Base Derivatives and Their Cytotoxic Activities on Three Human Cancer Cell Lines.

    Science.gov (United States)

    Nguyen, Van-Son; Shi, Ling; Wang, Sheng-Chun; Wang, Qiu-An

    2017-01-01

    Prenyl flavonoid icaritin (1) and β-anhydroicaritin (2) are two natural products with important biological and pharmacological effects. such as antiosteoporosis, estrogen regulation and antitumor properties. The present study investigates the synthesis and cytotoxic activities on three Human cancer cell lines (Hela, HCC1954 and SK-OV-3) of icaritin and β-anhydroicaritin Mannich base derivatives in vitro models. Preylated flavonoid icaritin (1) upon treatment with formic acid under microwave assistance gave another natural product β-anhydroicaritin (2) in good yield (89%). Based on Mannich reaction of 1 or 2 with various secondary amines and formaldehyde, two series eighteen new 6-aminomethylated flavonoids Mannich base derivatives 3-11 and 12-20 were synthesized. Their cytotoxic potential against three human cancer cell lines (Hela, HCC1954 and SK-OV-3) were evaluated by the standard MTT method with cis-Platin and Paclitaxel as positive control. Our research showed that most of these flavonoid Mannich base derivatives displayed equal or higher (lower IC50 values) cytotoxic activities than the positive control cis-Platin. Some compounds possess the IC50 value below 10µM. Compounds 6-(diisopropylamino)methyl- and 6-morpholinylmethyl substituted β-anhydroicaritin (15 and 19) showed selective cytotoxicity against HCC1954 cells (IC50 12.688 µM) and Hela cells (IC50 6.543 µM) respectively. Our finding most of icaritin and β-anhydroicaritin Mannich base derivatives possessing moderate to potent cytotoxicity against these three cancer cells (Hela, HCC1954 and SK-OV-3). Compound 15 and 19 showed selective cytotoxicity against HCC1954 cells and Hela cells respectively, they are potential and selective anticancer agent and worthy of further development.

  9. Choline-based biodegradable ionic liquid catalyst for Mannich-type ...

    Indian Academy of Sciences (India)

    A three-component Mannich-type reaction of aromatic aldehydes, ketones, and amines was cat- alyzed by a ..... ZnCl2 showed some catalytic activity and introducing. Table 1. The effects of different solvent systems to the. Mannich reaction.a. Entry. Solvent. Time (min) ... a significant role in promoting the catalytic activity of.

  10. Synthesis, analgesic activity and computational study of new isothiazolopyridines of Mannich base type.

    Science.gov (United States)

    Malinka, W; Swiatek, P; Filipek, B; Sapa, J; Jezierska, A; Koll, A

    2005-01-01

    A series of new 4-arylpiperazine derivatives of isothiazolopyridine of Mannich base type and their non-4-arylpiperazine analogues (3 and 4) were synthesized and assayed as potential analgesic agents. Pharmacological assay demonstrated that all the compounds prepared, without exception, displayed significant activity in the mouse writhing assay. The analgesic action, expressed as ED50, was found to be 2-10 times more potent than that of acetylsalicylic acid and 1.5-10 times weaker than that of morphine, these being used as standards. The toxicities (LD50) of the investigated derivatives varied and ranged from 250 to 2000 mg/kg. Additionally, the computational investigations were performed in order to find correlation between molecular structure and biological effects (toxicity, analgesic action) of discussed compounds. Useful model was found for toxicity assessment.

  11. Carbonic anhydrase inhibition and cytotoxicity studies of Mannich base derivatives of thymol.

    Science.gov (United States)

    Inci Gul, Halise; Yamali, Cem; Tugce Yasa, Asiye; Unluer, Elif; Sakagami, Hiroshi; Tanc, Muhammet; Supuran, Claudiu T

    2016-12-01

    Mannich bases of thymol were synthesized. The aminomethylation reaction was realised in the ortho position of the phenol for compounds 2 (dipropylamine), 3 (benzylamine), and 4 (dibenzylamine) while it was from para position for 1 (dimethylamine), 5 (piperidine), 6 (morpholine) and 7 (N-methylpiperazine). The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory effects of the compounds were asssessed against hCA I and hCA II. All compounds moderately inhibited hCA I and hCA II. The cytotoxicity of the compounds against four human oral squamous cell carcinoma cell lines were compared those against three normal oral cells. Tumor specificity values were about 2 or slightly more for the compounds 2, 3, 4, 5 and 6. Compound 2 showed cytostatic activity against OSCC cell lines at 16 to 32-fold lower concentrations as compared with normal cells. This suggests that compound 2 can be considered as cytotoxicity enhancing drug candidate for further investigations.

  12. Synthesis and Biological Evaluation of Mannich Bases of Isoxazoline Derivatives as Novel Anti-Microbial Agents

    Directory of Open Access Journals (Sweden)

    Pawar Sudhir

    2012-01-01

    Full Text Available A novel series of compounds were synthesized by condensation reaction of substituted acetophenone (1a-b with substituted aldehyde (2a-b in presence of alcoholic sodium hydroxide to get intermediate chalcones (3a-c, which were further treated with hydroxylamine hydrochloride in presence of sodium hydroxide to get isoxazolines derivatives (4a-c. The latter were refluxed with substituted primary amines and formaldehyde for 6-10 h to afford Mannich bases. The synthesized compounds were characterized on the basis of their spectral (IR, 1HNMR data and evaluated for the antimicrobial activity by using Zone of Inhibition by cup plate method and Minimum Inhibitory Concentration by broth dilution method.

  13. Synthesis, antiproliferative and antimicrobial activity of new Mannich bases bearing 1,2,4-triazole moiety.

    Science.gov (United States)

    Popiołek, Łukasz; Rzymowska, Jolanta; Kosikowska, Urszula; Hordyjewska, Anna; Wujec, Monika; Malm, Anna

    2014-12-01

    Abstract This study presents the synthesis, antiproliferative and antimicrobial evaluation of a new series of Mannich base derivatives containing 1,2,4-triazole system. New compounds were prepared by the reaction of 4,5-disubstituted 1,2,4-triazole-3-thiones with formaldehyde and various amines. The structures of the prepared compounds were confirmed by means of (1)H NMR, (13)C NMR and elemental analyses. Twelve compounds were evaluated for their in vitro antiproliferative activities against six chosen cancer cell lines. All synthesized compounds were screened for their in vitro antimicrobial activity by using the agar dilution technique. For 17 potentially active compounds, their antibacterial activity was confirmed on the basis of MIC (minimal inhibitory concentration) by broth microdilution method using the reference Gram-positive and Gram-negative bacterial strains.

  14. Efficient synthesis and antimicrobial evaluation of some Mannich bases from 2-arylidine-1-thia-4-azaspiro[4.5]decan-3-ones.

    Science.gov (United States)

    Hussein, Essam M; Masaret, Ghada S; Khairou, Khalid S

    2015-01-01

    Thiazolidinone, has been employed in the preparation of different important drugs required for treatment of inflammations, bacterial infections, and hypertension. Mannich bases have been shown to exhibit diverse biological activities, such as antibacterial, and antifungal activities. Spiroheterocycles including thiazolidine moiety have antimicrobial activity. In this study, a novel, rapid, and efficient protocol is developed for the synthesis of various 2-arylidine-1-thia-4-azaspiro[4.5]decan-3-ones using sodium dodecylbenzene sulfonate (DBSNa) as an inexpensive and readily available reagent in acetic acid at room temperature. High yields, easy work-up, and short reaction times are advantages of this procedure. The synthesized arylidines were undergone Mannich reaction with formaldehyde and secondary amines in absolute ethanol at room temperature to afford the corresponding N-Mannich bases. All prepared Mannich bases were evaluated for their antimicrobial activity. Good activity was noted for Mannich bases from 2-arylidine-1-thia-4-azaspiro[4.5]decan-3-ones, with some members recorded higher antimicrobial activity. Graphical abstractSynthesis of Mannich bases of 2-arylidine-1-thia-4-azaspiro[4.5]decan-3-ones.

  15. Enantioselective Direct Mannich-Type Reactions Catalyzed by Frustrated Lewis Acid/Brønsted Base Complexes.

    Science.gov (United States)

    Shang, Ming; Cao, Min; Wang, Qifan; Wasa, Masayuki

    2017-10-16

    An enantioselective direct Mannich-type reaction catalyzed by a sterically frustrated Lewis acid/Brønsted base complex is disclosed. Cooperative functioning of the chiral Lewis acid and achiral Brønsted base components gives rise to in situ enolate generation from monocarbonyl compounds. Subsequent reaction with hydrogen-bond-activated aldimines delivers β-aminocarbonyl compounds with high enantiomeric purity. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Synthesis, biological activities and SAR studies of new 3-substitutedphenyl-4-substitutedbenzylideneamino-1,2,4-triazole Mannich bases and bis-Mannich bases as ketol-acid reductoisomerase inhibitors.

    Science.gov (United States)

    Wang, Bao-Lei; Zhang, Li-Yuan; Liu, Xing-Hai; Ma, Yi; Zhang, Yan; Li, Zheng-Ming; Zhang, Xiao

    2017-12-15

    A series of new 3-substitutedphenyl-4-substitutedbenzylideneamino-1,2,4-triazole Mannich bases and bis-Mannich bases were synthesized through Mannich reaction with high yields. Their structures were confirmed by means of IR, 1 H NMR, 13 C NMR and elemental analysis. The preliminary bioassay indicated that compounds 7g, 7h and 7l exhibited potent in vitro inhibitory activities against ketol-acid reductoisomerase (KARI) with K i value of (0.38 ± 0.25), (6.59 ± 2.75) and (8.46 ± 3.99) μmol/L, respectively, and were comparable with IpOHA. They could be new KARI inhibitors for follow-up research. Some of the title compounds also exhibited obvious herbicidal activities against Echinochloa crusgalli and remarkable in vitro fungicidal activities against Physalospora piricola and Rhizoctonia cerealis. The SAR of the compounds were analyzed, in which the molecular docking revealed the binding mode of 7g with the KARI, and the 3D-QSAR results provided useful information for guiding further optimization of this kind of structures to discover new fungicidal agents towards Rhizoctonia cerealis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Carbon-based Solid Acid Catalyzed One-pot Mannich Reaction: A Facile Synthesis of β-Amino Carbonyl Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Davoodnia, Abolghasem; Tavakoli-Nishaburi, Afsaneh; Tavakoli-Hoseini, Niloofar [Islamic Azad University, Mashhad (Iran, Islamic Republic of)

    2011-02-15

    A simple and efficient method for the synthesis of β-amino carbonyl compounds by one-pot three-component Mannich reaction of acetophenone, aromatic aldehydes and aromatic amines using a carbon-based solid acid (CBSA), as an effective and reusable catalyst, is described. The present methodology offers several advantages such as simple procedure with an easy work-up, shorter reaction times, and high yields.

  18. Asymmetric Mannich Reaction of Isatin-Based Ketimines with α-Diazomethylphosphonates Catalyzed by Chiral Silver Phosphate.

    Science.gov (United States)

    Chen, Jing; Wen, Xiaojing; Wang, Yan; Du, Fei; Cai, Liu; Peng, Yungui

    2016-09-02

    An efficient asymmetric Mannich reaction of isatin-based ketimines with α-diazomethylphosphonates has been developed using a chiral binaphthanol-derived silver phosphate as the catalyst. This reaction allowed the construction of a series of chiral oxindoles bearing a quaternary stereocenter and amino group at the C3 position with up to 95% yields and 99% ee. Those products could be further transformed into promising densely functionalized compounds by merging of the oxindole and β-aminophosphonate.

  19. Chromatographic division of the semifinished products of the synthesis of washing dispersing additives of the Mannich base type

    Energy Technology Data Exchange (ETDEWEB)

    Gashko, G.P.; Chernyshev, I.A.; Klimenko, P.L.; Poletukha, V.V.

    1981-01-01

    Chormatographic and infrared spectral analysis is conducted of the intermediate products of synthesis of washing-dispersing additives of the Mannich base type. The chromatographic column is designed for eluation, collection and drying of various fractions (Fr). The eluation of the first Fr (oil and polybutene (1)) was conducted using 4 volumes of hexane; the second Fr (pure polybutenylphenol (II) by two volumes of benzene; the third Fr (modified Mannich bases) remained irreversibly adsorbed in the silica gel, while its volume was calculated from the difference between the initial suspension and the sum of suspensions of the isolated Fr. The infrared spectra of the hexane and benzene Fr were analyzed with the use of two acids of the aliphatic series and aromatic ones as the modifiers. The infrared spectra of all the hexane Fr are identical and are a total spectrum of I and the diluent oil. The infrared spectra of the benzene Fr in all cases are identical to the spectrum of II. Absorption bands of amines and amides are detected in the spectra of both types of Fr, which attests to the precision of chromatographic isolation. It is shown that the intermediate products of the synthesis of additives consist of the following components: alkan-naphthenic hydrocarbons (oil and I); II which does not enter into the reaction, and the basic product of Mannich condensation, which contains nitrogen.

  20. Synthesis, antibacterial, antifungal and anti-HIV activities of norfloxacin mannich bases.

    Science.gov (United States)

    Pandeya, S N; Sriram, D; Nath, G; De Clercq, E

    2000-02-01

    Mannich bases of norfloxacin were synthesized by reacting them with formaldehyde and several isatin derivatives. Their chemical structures have been confirmed by means of their IR, 1H-NMR data and by elemental analysis. Investigation of in vitro antimicrobial activity of compounds was done by the agar dilution method against 28 pathogenic bacteria, eight pathogenic fungi and anti-HIV activity against replication of HIV-1 (III B) in MT-4 cells. The in vivo antibacterial efficacy of selected derivatives was determined using a mouse infection model. All the synthesized compounds are more active than norfloxacin against the 13 bacteria tested. The compounds are also more active than the standard drug clotrimazole against Histoplasma capsulatum. Two compounds S-8 and S-9 have shown inhibition against HIV-1 (III B) with EC(50) values of 11.3 and 13.9 microgram/mL, respectively. In the mouse protection test, two compounds S-4 (ED(50): 1.25 mg/kg) and S-9 (ED(50): 1.62 mg/kg) are more active than norfloxacin (ED(50): 6mg/kg). Among the compounds tested, 1-ethyl-6-fluoro-1, 4-dihydro-4-oxo-7[[N(4)-[5'-bromo-3'-(4'-amino-5'-trimethoxybenzylpyr imidin-2'-yl]-imino-1'-isatinyl]methyl]N(1)-piperazinyl]-3-q uinoline carboxylicacid (S-9) showed promising activity in all the three tests.

  1. Simple spectrophotometric method for determination of melamine in liquid milks based on green Mannich reaction

    Science.gov (United States)

    Chansuvarn, Woravith; Panich, Sirirat; Imyim, Apichat

    2013-09-01

    A new and simple spectrophotometric method has been developed and validated for measuring the contamination of melamine in different milk products. The method is based upon measuring the absorption of the complex formed from melamine, 4-hydroxyacetophenone (Hap) and 1-pyrene carboxaldehyde (Pcd), which was adapted from the Mannich reaction. Quantitative analysis was done at a wavelength of 236 nm within a few minutes. The reaction was optimized by focusing on both obtaining high performance of the method and to concern the volatility and toxicity of used reagents. This method provided a linear dynamic range, limit of detection and limit of quantification of 0.100-3.78, 0.08 and 0.14 mg L-1, respectively. The relative standard deviation (RSD) was 3.6% (n = 10). The recoveries of melamine spiked liquid milk samples, with melamine concentrations of 0.63, 1.26, 1.89 and 2.52 mg L-1, were 87.7 ± 3.7%, 91.1 ± 8.8%, 89.2 ± 4.4% and 90.6 ± 3.6% (n = 3), respectively.

  2. Mannich base-connected syntheses mediated by ortho-quinone methides

    Science.gov (United States)

    Barta, Petra; Fülöp, Ferenc

    2018-01-01

    This article provides an overview about specifically modified Mannich reactions where the process involves an ortho-quinone methide (o-QM) intermediate. The reactions are classified on the basis of the o-QM source followed by the reactant, e.g., the dienophile partner in cycloaddition reactions (C=C or C=N dienophiles) or by the formation of multicomponent Mannich adducts. Due to the important pharmacological activities of these reactive o-QM intermediates, special attention is paid to the biological activity of these compounds. PMID:29623118

  3. Synthesis of some new series of Mannich base derivatives and their antimicrobial activity

    Directory of Open Access Journals (Sweden)

    Radha Krishnan Surendra Kumar

    2011-08-01

    Full Text Available A series of 1-[(4-substituted phenyl(hydrazinylmethyl]-1H-imidazole (1-6 were synthesized by Mannich reaction. Synthesized compounds 1-6 were confirmed by IR, ¹H NMR, ¹³C NMR, Mass and elemental analysis. Synthesized compounds 1-6 were screened for antimicrobial activity.

  4. In Vitro Antioxidant Evaluation of Some Mannich Bases which Contain Bis-1,2,4 -Triazole Derivative

    International Nuclear Information System (INIS)

    Parlak, A. E.; Karatepe, M.; Koparir, M.; Alayunt, N. O.; Keser, S.; Dastan, S. D.; Ulas, M.; Celik, S.

    2015-01-01

    This study aims to examine the antioxidant effects of some Mannich bases containing bis-1, 2, 4 triazole, which are synthesized afresh. The antioxidant activities of the derivatives were measured using different methods in this study, including reducing power capacity, metal chelating activity, superoxide anion radicals scavenging activity, H/sub 2/ O/sub 2/ scavenging activity and hydroxyl radical scavenging. As a result, derivatives had efficient antioxidant and free radical scavenging activity when compared to ascorbic acid, BHT and alpha-tocopherol as associated antioxidants. (author)

  5. Stereoselective mannich reactions of mono thiomalonates : & screening for peptidic triazolium salt based catalysts

    OpenAIRE

    Bahlinger, Annette

    2014-01-01

    Part I: The stereoselective synthesis of ß-amino thioesters is of high interest since they are versatile and common building blocks for a variety of pharmaceutically important compounds. Within this thesis a mild organocatalyzed approach for the synthesis of ß-amino thioesters by using mono thiomalonates (MTMs) as thioester enolate equivalents was developed. Those nucleophiles proved to be highly reactive in Mannich reactions providing for acyclic ß2-amino thioesters and ß2,3,3-amino thioeste...

  6. Design, synthesis and anticonvulsant properties of new N-Mannich bases derived from 3-phenylpyrrolidine-2,5-diones.

    Science.gov (United States)

    Kamiński, Krzysztof; Obniska, Jolanta; Chlebek, Iwona; Wiklik, Beata; Rzepka, Sabina

    2013-11-01

    The synthesis and anticonvulsant properties of new N-Mannich bases of 3-phenyl- (9a-d), 3-(2-chlorophenyl)- (10a-d), 3-(3-chlorophenyl)- (11a-d) and 3-(4-chlorophenyl)-pyrrolidine-2,5-diones (12a-d) were described. The key synthetic strategies involve the formation of 3-substituted pyrrolidine-2,5-diones (5-8), and then aminoalkylation reaction (Mannich-type) with formaldehyde and corresponding secondary amines, which let to obtain the final compounds 9a-d, 10a-d, 11a-d and 12a-d in good yields. Initial anticonvulsant screening was performed in mice (ip) using the maximal electroshock (MES) and subcutaneous pentylenetetrazole (scPTZ) seizures tests. The most effective compounds in mice were tested after oral administration in rats. The acute neurological toxicity was determined applying the minimal motor impairment rotarod test. The in vivo results revealed that numerous compounds were effective especially in the MES test (model of human tonic-clonic seizures). The most active in the MES seizures in rats was 1-[(4-benzyl-1-piperidyl)methyl]-3-(2-chlorophenyl)pyrrolidine-2,5-dione (10c) which showed ED50 value of 37.64mg/kg. It should be stressed that this molecule along with 9a, 9d and 10d showed protection in the psychomotor seizure test (6-Hz), which is known as an animal model of therapy-resistant epilepsy. Furthermore compounds 9a, 9d and 10d were also tested in the pilocarpine-induced status prevention (PISP) test to assess their potential effectiveness in status epilepticus. For the most promising molecule 9d an influence on human CYP3A4 isoform of P-450 cytochrome was studied in vitro. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. A chiral organic base catalyst with halogen-bonding-donor functionality: asymmetric Mannich reactions of malononitrile with N-Boc aldimines and ketimines.

    Science.gov (United States)

    Kuwano, Satoru; Suzuki, Takumi; Hosaka, Yusei; Arai, Takayoshi

    2018-03-29

    A chiral organic base catalyst with halogen-bonding-donor functionality has been developed. This quinidine-derived acid/base catalyst smoothly promoted the asymmetric Mannich reaction of malononitrile and various N-Boc imines with up to 98% ee. The cooperative interaction with both substrates was responsible for the high activity that allowed a reduction of the catalyst amount to 0.5 mol%.

  8. SYNTHESIS AND ANTIMICROBIAL ACTIVITIES OF NEW 1,2,4- TRIAZOLES, MANNICH BASES, CONAZOLES, AND FLUOROQUINOLONES

    Directory of Open Access Journals (Sweden)

    Şule CEYLAN

    2016-09-01

    Full Text Available Abstract: Triazoles are heterocyclic compounds which have been of interest in the development of novel compounds with antidepressant, anti-inflammatory, analgesic, antibacterial, antimycobacterial, antifungal, antiviral, anticancer, and other activities. In this article, a series of fluorine- and piperazine-containing some novel biologically active 1,2,4-triazole-3-one derivatives were synthesized by the Mannich reaction of triazole intermediates. The structures for novel synthesized compounds were elucidated using elemental analysis and FT IR, 13C NMR, 1H NMR, EI MS techniques. These compounds were investigated in vitro for their antimicrobial properties and several compounds have fungicidal activity against Candida albicans and Saccharomyces cerevisiae. And also some of the compounds exhibited excellent activity on Mycobacterium smegmatis, a nonpigmented fast-rising mycobacterium, at the concentration of <1 μg/mL is better than standard drug streptomycin.

  9. Synthesis and Cytotoxic Evaluation of a Series of 2-Amino-Naphthoquinones against Human Cancer Cells

    Directory of Open Access Journals (Sweden)

    Thiago A. P. de Moraes

    2014-08-01

    Full Text Available The cytotoxicity of a series of aminonaphthoquinones resulting from the reaction of suitable aminoacids with 1,4-naphthoquinone was assayed against SF-295 (glioblastoma, MDAMB-435 (breast, HCT-8 (colon, HCT-116 (colon, HL-60 (leukemia, OVCAR-8 (ovarian, NCI-H358M (bronchoalveolar lung carcinoma and PC3-M (prostate cancer cells and also against PBMC (peripheral blood mononuclear cells. The results demonstrated that all the synthetic aminonaphthoquinones had relevant cytotoxic activity against all human cancer lines used in this experiment. Five of the compounds showed high cytotoxicity and selectivity against all cancer cell lines tested (IC50 = 0.49 to 3.89 µg·mL−1. The title compounds were less toxic to PBMC, since IC50 was 1.5 to eighteen times higher (IC50 = 5.51 to 17.61 µg·mL−1 than values shown by tumour cell lines. The mechanism of cell growth inhibition and structure–activity relationships remains as a target for future investigations.

  10. Antimicrobial and hypoglycemic activities of novel N-Mannich bases derived from 5-(1-adamantyl)-4-substituted-1,2,4-triazoline-3-thiones.

    Science.gov (United States)

    Al-Abdullah, Ebtehal S; Al-Tuwaijri, Hanaa M; Hassan, Hanan M; Haiba, Mogedda E; Habib, Elsayed E; El-Emam, Ali A

    2014-12-11

    The reaction of 5-(1-adamantyl)-4-ethyl or allyl-1,2,4-triazoline-3-thione with formaldehyde solution and various 1-substituted piperazines yielded the corresponding N-Mannich bases. The newly synthesized N-Mannich bases were tested for in vitro inhibitory activities against a panel of Gram-positive and Gram-negative bacteria and the yeast-like pathogenic fungus Candida albicans. Six compounds showed potent antibacterial activity against one or more of the tested microorganisms, while two compounds exhibited moderate activity against the tested Gram-positive bacteria. None of the newly synthesized compounds were proved to possess marked activity against Candida albicans. The oral hypoglycemic activity of six compounds was determined in streptozotocin (STZ)-induced diabetic rats. Four compounds produced significant strong dose-dependent reduction of serum glucose levels, compared to gliclazide at 10 mg/kg dose level (potency ratio > 75%).

  11. Polyether-substituted mannich-bases as fuel and ash-free dispersion compounds. Polyetersubstituerte mannichbaser som brennstoff og askefrie dispergeringsmidler

    Energy Technology Data Exchange (ETDEWEB)

    Blain, D.A.; Cardis, A.B.

    1994-07-04

    The invention relates to reaction products formed from polyether-modified phenol-containing mannich-bases. They have appeared to be efficient ash-free dispersion means and detergents for hydrocarbon fuels and lubricants. According to the invention, the reaction products are formed by (1) transforming phenol or a c[sub 1] to about a c[sub 4]0 phenol with a suitable primary or secondary amine and a c[sub 1] to about a c[sub 3]0 aldehyde, thereafter (2) transforming the resulting medium product, according to (1), with an alkali metal or an alkali metal salt thereof, and afterwards (3), transforming the product, according to (2), with a c[sub 2] to about c[sub 8] alkylene epoxide or a mixture thereof for producing a polyether-substituted mannich-base. 1 tab.

  12. Antimicrobial and Hypoglycemic Activities of Novel N-Mannich Bases Derived from 5-(1-Adamantyl-4-substituted-1,2,4-triazoline-3-thiones

    Directory of Open Access Journals (Sweden)

    Ebtehal S. Al-Abdullah

    2014-12-01

    Full Text Available The reaction of 5-(1-adamantyl-4-ethyl or allyl-1,2,4-triazoline-3-thione with formaldehyde solution and various 1-substituted piperazines yielded the corresponding N-Mannich bases. The newly synthesized N-Mannich bases were tested for in vitro inhibitory activities against a panel of Gram-positive and Gram-negative bacteria and the yeast-like pathogenic fungus Candida albicans. Six compounds showed potent antibacterial activity against one or more of the tested microorganisms, while two compounds exhibited moderate activity against the tested Gram-positive bacteria. None of the newly synthesized compounds were proved to possess marked activity against Candida albicans. The oral hypoglycemic activity of six compounds was determined in streptozotocin (STZ-induced diabetic rats. Four compounds produced significant strong dose-dependent reduction of serum glucose levels, compared to gliclazide at 10 mg/kg dose level (potency ratio > 75%.

  13. Antineoplastic Isoflavonoids Derived from Intermediate ortho-Quinone Methides Generated from Mannich Bases.

    Science.gov (United States)

    Frasinyuk, Mykhaylo S; Mrug, Galyna P; Bondarenko, Svitlana P; Khilya, Volodymyr P; Sviripa, Vitaliy M; Syrotchuk, Oleksandr A; Zhang, Wen; Cai, Xianfeng; Fiandalo, Michael V; Mohler, James L; Liu, Chunming; Watt, David S

    2016-03-17

    The regioselective condensations of various 7-hydroxyisoflavonoids with bis(N,N-dimethylamino)methane in a Mannich reaction provided C-8 N,N-dimethylaminomethyl-substituted isoflavonoids in good yield. Similar condensations of 7-hydroxy-8-methylisoflavonoids led to the C-6-substituted analogs. Thermal eliminations of dimethylamine from these C-6 or C-8 N,N-dimethylaminomethyl-substituted isoflavonoids generated ortho-quinone methide intermediates within isoflavonoid frameworks for the first time. Despite other potential competing outcomes, these ortho-quinone methide intermediates trapped dienophiles including 2,3-dihydrofuran, 3,4-dihydro-2H-pyran, 3-(N,N-dimethylamino)-5,5-dimethyl-2-cyclohexen-1-one, 1-morpholinocyclopentene, and 1-morpholinocyclohexene to give various inverse electron-demand Diels-Alder adducts. Several adducts derived from 8-N,N-dimethylaminomethyl-substituted isoflavonoids displayed good activity in the 1-10 μm concentration range in an in vitro proliferation assay using the PC-3 prostate cancer cell line. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Achiral Mannich-Base Curcumin Analogs Induce Unfolded Protein Response and Mitochondrial Membrane Depolarization in PANC-1 Cells

    Directory of Open Access Journals (Sweden)

    Gábor J. Szebeni

    2017-10-01

    Full Text Available Achiral Mannich-type curcumin analogs have been synthetized and assayed for their cytotoxic activity. The anti-proliferative and cytotoxic activity of curcuminoids has been tested on human non-small-cell lung carcinoma (A549, hepatocellular carcinoma (HepG2 and pancreatic cancer cell line (PANC-1. Based on the highest anti-proliferative activity nine drug candidates were further tested and proved to cause phosphatidylserine exposure as an early sign of apoptosis. Curcumin analogs with the highest apoptotic activity were selected for mechanistic studies in the most sensitive PANC-1 cells. Cytotoxic activity was accompanied by cytostatic effect since curcumin and analogs treatment led to G0/G1 cell cycle arrest. Moreover, cytotoxic effect could be also detected via the accumulation of curcuminoids in the endoplasmic reticulum (ER and the up-regulation of ER stress-related unfolded protein response (UPR genes: HSPA5, ATF4, XBP1, and DDIT3. The activated UPR induced mitochondrial membrane depolarization, caspase-3 activation and subsequent DNA breakdown in PANC-1 cells. Achiral curcumin analogs, C509, C521 and C524 possessed superior, 40-times more potent cytotoxic activity compared to natural dihydroxy-dimetoxycurcumin in PANC-1 cells.

  15. Synthesis, FT-IR, 1H, 13C NMR, ESI MS and PM5 studies of a new Mannich base of polyether antibiotic - Lasalocid acid and its complexes with Li+, Na+ and K+ cations

    Science.gov (United States)

    Huczyński, Adam; Rutkowski, Jacek; Brzezinski, Bogumil; Bartl, Franz

    2013-03-01

    The polyether antibiotic Lasalocid acid has been converted to its Mannich base derivative by a chemoselective one-pot reaction with formaldehyde and morpholine through the decarboxylation process. Spectroscopic studies of the structure of this new derivative have shown that in this ortho-phenol Mannich base the Osbnd H⋯N intarmolecular hydrogen bond is present. The compound forms complexes with Li+, Na+ and K+ cations of exclusively 1:1 stoichiometry. The structures of these complexes have been studied and visualized by semi-empirical calculation based on results of spectrometric and spectroscopic investigation. It is demonstrated that in contrast to Lasalocid acid the novel Mannich type derivative forms preferential complexes with Li+ cation.

  16. Aminoacids as the Amine Component in the Mannich Reaction

    Science.gov (United States)

    Agababyan, A. G.; Gevorgyan, G. A.; Mndzhoyan, O. L.

    1982-04-01

    The review is devoted to the aminomethylation of the CH-, NH-, and the PH-acid residues by aminoacids. Data are presented on the biological activities of certain Mannich bases derived from aminoacids. The bibliography includes 132 references.

  17. Antitumor Effect of the Mannich Base(1,3-bis-((3-Hydroxynaphthalen-2-ylphenylmethylurea on Hepatocellular Carcinoma

    Directory of Open Access Journals (Sweden)

    Vadanasundari Vedarethinam

    2016-05-01

    Full Text Available The present study was designed to evaluate the antitumor effects of the synthetic Mannich base 1,3-bis-((3-hydroxynaphthalen-2-ylphenylmethylurea (1,3-BPMU against HEP-G2 hepatoma cells and diethylnitrosamine (DEN-induced hepatocarcinoma (HCC in albino rats. In vitro analysis results revealed that 1,3-BPMU showed significant cytotoxicity and cell growth inhibition in HEP-G2 hepatoma cells in a concentration-dependent manner. Furthermore, flow cytometry results indicated that 1,3-BPMU enhanced early and late apoptosis. The maximum apoptosis was exhibited at a concentration of 100 μg/mL of 1,3-BPMU. In in vivo analysis, DEN treatment increased the content of nucleic acids, LPO and the activities of AST, ALT, ALP, LDH, γGT and 5’NT with decreased antioxidant activity as compared to control rats. However, 1,3-BPMU treatment to DEN-induced rats decreased the content of nucleic acids, LPO and the activities of AST, ALT, ALP, LDH, γGT and 5’NT and increased the activities of SOD, CAT, GPx, GST and GR (p < 0.05. Furthermore, 1,3-BPMU enhanced the apoptosis via upregulation of caspase-3 and caspase-9 and the downregulation of Bcl-2 and Bcl-XL mRNA expression as compared to DEN-induced rats. Histological and ultrastructural investigation showed that 1,3-BPMU treatment renovated the internal architecture of the liver in DEN-induced rats. In this study, the molecular and pre-clinical results obtained by treatment of DEN-induced rats with 1,3-BPMU suggested that 1,3-BPMU might be considered as an antitumor compound in the future.

  18. Synthesis, Characterization, and Biological Activity of Novel Schiff and Mannich Bases of 4-Amino-3-(N-phthalimidomethyl-1,2,4-triazole-5-thione

    Directory of Open Access Journals (Sweden)

    Uzma Yunus

    2013-01-01

    Full Text Available The present work describes the syntheses and antimicrobial activity studies of a series of novel Schiff bases (4a–4i and their Mannich bases (5a–5h starting from 4-amino-3-(N-phthalimido-methyl-1,2,4-triazole-5-thione (3. All the synthesized compounds were characterized by IR, 1H-NMR, 13C-NMR, and MS. All the synthesized compounds were screened for four Gram-negative strains, one Gram-positive strain of bacteria, and one diploid fungal strain. In general the antimicrobial activity increased remarkably on the introduction of azomethine functionality in parent triazole (3. The antimicrobial activity further improved when morpholine group was added to them except for Enterobacter cloacae, where loss of activity was observed. The results are promising and show that the fine tuning of the structures (5a, 5b, 5e, 5f, and 5h can lead to some new antimicrobial compounds.

  19. Synthesis of Schiff and Mannich Bases of Isatin Derivatives with 4-Amino-4,5-Dihydro-1H-1,2,4-Triazole-5-Ones

    Directory of Open Access Journals (Sweden)

    Hakan Bektas

    2008-09-01

    Full Text Available Ethyl imidate hydrochlorides 1 were prepared by passing HCl gas through solutions of substituted benzyl cyanides and absolute ethanol. Ethoxycarbonylhydrazones 2 were synthesized from the reaction of compounds 1 with ethyl carbazate. Treatment of 2 with hydrazine hydrate leads to the formation of substituted 4-amino-4,5-dihydro-1H-1,2,4-triazole-5-ones 3. Isatin and 5-chloroisatin were added to 3 to form Schiff bases 4 and N-Mannich bases 5 of these compounds were synthesized by reacting with formaldehyde and piperidine. Their chemical structures were confirmed by means of IR, 1H- and 13C-NMR data and by elemental analysis.

  20. Synthesis Characterization and Biological Activity Study of New Schiff and Mannich Bases and Some Metal Complexes Derived from Isatin and Dithiooxamide

    Science.gov (United States)

    Abdulghani, Ahlam J.; Abbas, Nada M.

    2011-01-01

    Two new Schiff and Mannich bases, namely, 1-Morpholinomethyl-3(1′ -N-dithiooxamide)iminoisatin (LIH) and 1-diphenylaminomethyl-3-1′-N-dithiooxamide)iminoisatin (LIIH), were prepared from condensation reaction of new Schiff base 3-(1′-N-dithiooxamide)iminoisatin (SBH) with morpholine or diphenylamine respectively in presence of formaldehyde . The structures were characterized by IR, 1HNMR, mass spectrometry, and CHN analyses. Metal complexes of the two ligands were synthesized, and their structures were characterized by elemental analyses, atomic absorption, IR and UV-visible spectra, molar conductivity, and magnetic moment determination. All complexes showed octahedral geometries except palladium complexes which were square planar. The biological activity of the prepared compounds and some selected metal complexes was tested against three types of bacteria and against cell line of human epidermoid larynx carcinoma (Hep-2). PMID:21949661

  1. Kinetic studies of the impact of thiocyanate moiety on the catalytic properties of Cu(II) and Fe(III) complexes of a new Mannich base

    Science.gov (United States)

    Ayeni, Ayowole O.; Watkins, Gareth M.

    2018-04-01

    Four new metal complexes of a novel Mannich base 5-methyl-2-((4-(pyridin-2-yl)piperazin-1-yl)methyl)phenol (HL) have been prepared. The compounds were characterized by an array of analytical and spectroscopic methods including Nuclear Magnetic Resonance, Infra-red and UV-Visible spectroscopy. Compounds 1-4 behaved as effective catalysts towards the oxidation of 3,5-di-tert-butylcatechol (3,5-DTBC) to its corresponding quinone in the presence of molecular oxygen in DMF solution while compound 4 proved to be the best catalyst with a turnover rate of 17.93 ± 1.10 h-1 as other complexes showed lower rates of oxidation. Also with the exception of dinuclear iron complex (4); thiocyanate containing Cu(II) complex exhibited lower catecholase activity compared to the Cu(II) complex without it.

  2. Evaluation of net antioxidant activity of mono- and bis-Mannich base hydrochlorides and 3-keto-1,5-bisphosphonates from their ProAntidex parameter

    Science.gov (United States)

    Lahbib, Karima; Tarhouni, Mohamed; Touil, Soufiane

    2015-07-01

    A series of mono- and bis-Mannich base hydrochlorides and of 3-keto-1,5-bisphosphonates were prepared and characterized on the basis of their infrared (IR), 1H, 13C and 31P NMR spectral data. All the title compounds were tested for their in vitro antioxidant activities by 1,1-diphenyl-2-picrylhydrazyl (DPPH), H2O2, hydroxyl radical and Ferric Reducing Power (FRP) methods. The antioxidant activity of these compounds was analyzed simultaneously with their pro-oxidant capacity. The ratio of pro-oxidant to the antioxidant activity (ProAntidex) represents a useful index of the net free radical scavenging potential of the synthesized compounds. Ferrous, calcium and magnesium ion chelating abilities were also evaluated. All the tested compounds showed significant antioxidant activity and high ProAntidex.

  3. Mannich Bases as Enone Precursors for Water-Mediated Efficient Synthesis of 2,3,6-Trisubstituted Pyridines and 5,6,7,8-Tetrahydroquinolines.

    Science.gov (United States)

    Hanashalshahaby, Essam Hamied Ahmed; Unaleroglu, Canan

    2015-06-08

    A highly efficient, regioselective, and environmentally friendly method has been developed for water-mediated synthesis of 2,3,6-trisubstituted pyridines and 5,6,7,8-tetrahydroquinolines. The introduced method allows easy preparation of various polysubstituted pyridines and 5,6,7,8-tetrahydroquinolines via domino reaction of an enolizable ketone, ammonia and enones derived from different Mannich bases in mild reaction conditions. Montmorillonite K-10 promoted this one-pot three-component reaction and gave both new and known 2,3,6-trisubstituted pyridines and 5,6,7,8-tetrahydroquinolines in good yields. The reaction protocol provides a wide array of functionality in construction of polysubstituted pyridines and 5,6,7,8-tetrahydroquinolines from commercially available starting materials in easily applicable and environmentally friendly conditions.

  4. Mannich base oil additives

    Energy Technology Data Exchange (ETDEWEB)

    Horodysky, A.G.; Gemmill, R.M.

    1988-11-29

    This patent describes a method for reducing the coefficient of friction of a liquid lubricating oil which comprises adding to such an oil a coefficient of friction-reducing amount of the product resulting from reacting an aldehyde; at least one amine selected from the group consisting of primary amines containing from 8 to 18 carbon atoms and polyalkylenopolyamines of the formula NHX(R/sup 4/NH)/sub n/R/sup 2/ wherein R/sup 2/ and X are selected from the group consisting of hydrogen, a hydrocarbyl group and a hydroxyhydrocarbyl group, either containing 6 to 18 carbon atoms, R/sup 4/ is an alkylene group containing 1 to 5 carbon atoms and n is 1 to 10; and, at least one alkyl-substituted phenol wherein the alkyl is branched, contains from 16 to 40 carbon atoms and is derived from a 1-olefin oligomer containing from 8 to 12 carbon atoms, the reaction being carried out from about 60/sup 0/C to about 130/sup 0/C using the reactants in a respective molar ratio of about 1.0-2.0:1.0-2.0:1.0.

  5. Asymmetric synthesis of α-amino acids via homologation of Ni(II) complexes of glycine Schiff bases. Part 2: aldol, Mannich addition reactions, deracemization and (S) to (R) interconversion of α-amino acids.

    Science.gov (United States)

    Sorochinsky, Alexander E; Aceña, José Luis; Moriwaki, Hiroki; Sato, Tatsunori; Soloshonok, Vadim

    2013-11-01

    This review provides a comprehensive treatment of literature data dealing with asymmetric synthesis of α-amino-β-hydroxy and α,β-diamino acids via homologation of chiral Ni(II) complexes of glycine Schiff bases using aldol and Mannich-type reactions. These reactions proceed with synthetically useful chemical yields and thermodynamically controlled stereoselectivity and allow direct introduction of two stereogenic centers in a single operation with predictable stereochemical outcome. Furthermore, new application of Ni(II) complexes of α-amino acids Schiff bases for deracemization of racemic α-amino acids and (S) to (R) interconversion providing additional synthetic opportunities for preparation of enantiomerically pure α-amino acids, is also reviewed. Origin of observed diastereo-/enantioselectivity in the aldol, Mannich-type and deracemization reactions, generality and limitations of these methodologies are critically discussed.

  6. Recent developments concerning the application of the Mannich reaction for drug design.

    Science.gov (United States)

    Biersack, Bernhard; Ahmed, Khursheed; Padhye, Subhash; Schobert, Rainer

    2018-01-01

    The versatile multicomponent Mannich reaction occupies a salient position in organic chemistry and drug design. Sound knowledge of its scope and variations and of the biological activities of Mannich bases is crucial for the development and improvement of drugs for various diseases. Areas covered: The following article provides an overview of the latest developments in the field of drugs based on the Mannich reaction. Web-based literature searching tools such as PubMed and SciFinder were applied to obtain useful articles. In addition, pertinent literature that was recently published by the authors is discussed in this manuscript. The chemical structures of bioactive Mannich bases are also given. Expert opinion: The Mannich reaction represents a feasible and cost-effective procedure with great potential for drug development. Several newly discovered Mannich bases exhibit sound activities against various human diseases as well as favorable pharmacokinetics. Thus, scientific research about Mannich bases is prospering and appears very attractive both for chemists and for clinicians.

  7. Synthesis of formazans from Mannich base of 5-(4-chlorophenyl amino-2-mercapto-1,3,4-thiadiazole as antimicrobial agents

    Directory of Open Access Journals (Sweden)

    Pramilla Sah

    2014-04-01

    Full Text Available 5-(4-Chlorophenyl amino-2-mercapto-1,3,4-thiadiazole (I was refluxed with formaldehyde and ammonium chloride in ethanol yielding the Mannich base 5-(4-chloro phenyl amino-3-aminomethyl-2-mercapto-1,3,4-thiadiazole (II. Esterification with 4-chloro-(2,6-dinitro phenoxy-ethyl acetate (III under anhydrous conditions gave the intermediate (IV. Subsequent hydrazinolysis with hydrazine hydrate gave the corresponding hydrazide 3-amino methyl-5-(4-chloro phenyl amino-2-mercapto-4′-(2′,6′-dinitro phenoxy-acetyl hydrazide (V. The hydrazide was converted into the Schiff bases (VIa–b by reacting with 2-chlorobenzaldehyde and 3-methoxy-4-hydroxy benzaldehyde in presence of methanol containing 2–3 drops of acetic acid. Diazotisation with aromatic amines, sulphanilic acid and sulphur drugs gave the formazans (VIIa–g respectively. Chemical structures have been established by elemental analysis and the spectral techniques of FTIR, 1H NMR and mass. Antimicrobial activity (in vitro was evaluated against the two pathogenic bacterial strains. Escherichia coli and Salmonella typhi, three fungal strains Aspergillus niger, Penicillium species and Candida albicans. The compounds have shown moderate activity.

  8. Synthesis, growth, physicochemical properties and DFT calculations of 2-naphthol substituted Mannich base 1-(morpholino(phenyl) methyl) naphthalen-2-ol: A non linear optical single crystal

    Science.gov (United States)

    Dennis Raj, A.; Jeeva, M.; Shankar, M.; Venkatesa Prabhu, G.; Vimalan, M.; Vetha Potheher, I.

    2017-11-01

    2-Naphthol substituted Mannich base 1-morpholino(phenyl)methyl)naphthalen-2-ol (MPMN), a potential NLO active organic single crystal was developed using acetonitrile as a solvent by slow evaporation method. The experimental and theoretical analysis made towards the exploitation in the field of electro-optic and NLO applications. The cubic structure with non-centrosymmetric space group Cc was confirmed and cell dimensions of the grown crystal were obtained from single crystal X-ray diffraction (XRD) study. The formation of the Csbnd Nsbnd C vibrational band at 1115 cm-1 in Fourier Transform Infra-Red (FTIR) analysis confirms the formation of MPMN compound. The placement of protons and carbons of MPMN were identified from Nuclear Magnetic Resonance Spectroscopy (NMR) analysis. The wide optical absorption window and the lower cutoff wavelength of MPMN show the suitability of the material for the various laser related applications. The presence of dislocations and growth pattern of crystal were analyzed using chemical etching technique. The Second Harmonic Generation (SHG) of MPMN was found to be 1.57 times greater than the standard KDP crystal. The laser damage threshold was measured by using Nd: YAG laser beam passed through the sample and it was found to be 1.006 GW/cm2. The electronic structure of the molecular system and the optical properties were also studied from quantum chemical calculations using Density Functional Theory (DFT) and reported for the first time.

  9. Synthesis and characterization of isothiocyanato complexes of dioxotungsten(VI with mannich base ligands: Precursors for the preparation of pure phase nanosized tungsten(VI trioxide

    Directory of Open Access Journals (Sweden)

    Rimpy Gupta

    2016-05-01

    Full Text Available Six isothiocyanato complexes of dioxotungsten(VI with Mannich base ligands having the formula [WO2(NCS2L-L] (where L-L = N-[1-morpholinobenzyl] acetamide (MBA, N-[1-piperidinobenzyl] acetamide (PBA, N-[1-morpholino(-4-nitrobenzyl] benzamide (MPNBB, N-[1-piperidino(-3-nitrobenzyl] benzamide (PMNBB, N-[1-morpholino(-2-nitrobenzyl] acetamide (MONBA and N-[1-morpholino(-3-nitrobenzyl] acetamide (MMNBA have been synthesized by the reaction of tetraisothiocyanatodioxotungsten(VI anion with the ethanolic solution of the corresponding ligand in aqueous medium in the presence of HCl. The complexes have been characterized by elemental analyses, FTIR, 1H NMR, 13C NMR, DEPT, ESI mass spectra, TGA/DTA, molar conductivity measurements, electronic spectra, magnetic moment measurements, SEM and XRD. Finally, the ligands and the corresponding complexes have been tested against Agrobacterium sp BN-2A and it has been observed that complexes show enhanced activity as compared to the ligands. The complexes on calcination give rod-like WO3 nanoparticles.

  10. Synthesis and antibacterial evaluation of some novel mannich ...

    African Journals Online (AJOL)

    Substituted benzimidazoles are known for their chemotherapeutic importance and many pharmacological properties. In this paper, we synthesized some novel Mannich bases of benzimidazole derivatives. The synthesized compounds were characterized by their physical and spectral data and in vitro antibacterial activity of ...

  11. Synthesis, Characterization and Antimicrobial Studies of a New Mannich Base N-[Morpholino(phenyl)methyl]acetamide and Its Cobalt(II), Nickel(II) and Copper(II) Metal Complexes

    OpenAIRE

    L. Muruganandam; K. Krishnakumar

    2012-01-01

    A new Mannich base N-[morpholino(phenyl)methyl]acetamide (MBA), was synthesized and characterized by spectral studies. Chelates of MBA with cobalt(II), nickel(II) and copper(II) ions were prepared and characterized by elemental analyses, IR and UV spectral studies. MBA was found to act as a bidentate ligand, bonding through the carbonyl oxygen of acetamide group and CNC nitrogen of morpholine moiety in all the complexes. Based on the magnetic moment values and UV-Visible spectral data, tetrac...

  12. Catalytic Asymmetric Nitro-Mannich Reactions with a Yb/K Heterobimetallic Catalyst

    Directory of Open Access Journals (Sweden)

    Tatsuya Nitabaru

    2010-03-01

    Full Text Available A catalytic asymmetric nitro-Mannich (aza-Henry reaction with rare earth metal/alkali metal heterobimetallic catalysts is described. A Yb/K heterobimetallic catalyst assembled by an amide-based ligand promoted the asymmetric nitro-Mannich reaction to afford enantioenriched anti-b-nitroamines in up to 86% ee. Facile reduction of the nitro functionality allowed for efficient access to optically active 1,2-diamines.

  13. Green synthesis, biological and spectroscopic study on the interaction of multi-component Mannich bases of imidazo[2,1-b]benzothiazoles with human serum albumin.

    Science.gov (United States)

    Maddili, Swetha K; Yandrati, Leela Prasad; Siddam, Shakuntala; Kannekanti, Vijaya Kumar; Gandham, Himabindu

    2017-11-01

    A series of Mannich bases of imidazo[2, l-b]benzothiazoles were prepared through one-pot multi-component reaction in the presence of water as an eco-friendly solvent. All the synthesized compounds were confirmed from IR, 1 HNMR, 13 CNMR, and Mass spectroscopy. Evaluation of in vitro anti-inflammatory and anti-microbial activities of all the synthesized derivatives was further accomplished. These results clearly displayed that compound 6d exhibited outstanding anti-inflammatory activity with a percentage inhibition of 70.23% by membrane stabilization method whereas 67.54% at 100μgmL -1 by the albumin denaturation method, which is comparable to the standard Diclofenac. Further screening against five fungal species (C. albicans ATCC 76615, C. mycoderma, C. utilis, A. flavus, and B. yeast) along with four gram positive (Methicillin-resistant S. aureus N315 (MRSA), Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 21216, and Micrococcus luteus ATCC 4698), and six Gram-negative bacterial strains (Escherichia coli DH52, Escherichia coli JM109, Salmonella dysenteriae, Pseudomonas aeruginosa ATCC 27853, Bacillus proteus ATCC13315 and Bacillus typhi) was carried out. These findings manifested that compound 7c displayed excellent antifungal efficacy while compound 7b revealed significant anti-microbial activity. In addition binding behaviour of compound 7b was investigated by binding study between calf thymus DNA and compound 7b by UV-Vis absorption spectroscopy and further research about HSA interactions was carried out. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Single-step synthesis of a new series of meso di-Mannich bases from the cyclic aminal (2S,7R,11S,16R)-1,8,10,17-tetraazapentacyclo [8.8.1.1..sup.8,17./sup.0..sup.2,7./sup.0.sup.11,16./sup.]icosane and p-substituted phenols

    Czech Academy of Sciences Publication Activity Database

    Rivera, A.; Quiroga, D.; Ríos-Motta, J.; Eigner, V.; Dušek, Michal

    2013-01-01

    Roč. 7, JUN (2013), s. 100 ISSN 1752-153X Institutional support: RVO:68378271 Keywords : p-substituted phenols * Mannich bases * single-step synthesis * Jana2006 Subject RIV: CC - Organic Chemistry Impact factor: 1.663, year: 2013

  15. Synthesis, Characterization and Antimicrobial Studies of a New Mannich Base N-[Morpholino(phenylmethyl]acetamide and Its Cobalt(II, Nickel(II and Copper(II Metal Complexes

    Directory of Open Access Journals (Sweden)

    L. Muruganandam

    2012-01-01

    Full Text Available A new Mannich base N-[morpholino(phenylmethyl]acetamide (MBA, was synthesized and characterized by spectral studies. Chelates of MBA with cobalt(II, nickel(II and copper(II ions were prepared and characterized by elemental analyses, IR and UV spectral studies. MBA was found to act as a bidentate ligand, bonding through the carbonyl oxygen of acetamide group and CNC nitrogen of morpholine moiety in all the complexes. Based on the magnetic moment values and UV-Visible spectral data, tetracoordinate geometry for nitrato complexes and hexacoordinate geometry for sulphato complexes were assigned. The antimicrobial studies show that the Co(II nitrato complex is more active than the other complexes.

  16. Stereodivergent Mannich reaction of bis(trimethylsilyl)ketene acetals with N-tert-butanesulfinyl imines by Lewis acid or Lewis base activation, a one-pot protocol to obtain chiral β-amino acids.

    Science.gov (United States)

    Cantú-Reyes, Margarita; Alvarado-Beltrán, Isabel; Ballinas-Indilí, Ricardo; Álvarez-Toledano, Cecilio; Hernández-Rodríguez, Marcos

    2017-09-20

    We report a one-pot synthesis of chiral β 2,2,3 -amino acids by the Mannich addition of bistrimethylsilyl ketene acetals to N-tert-butanesulfinyl imines followed by the removal of the chiral auxiliary. The synthesis and isolation of pure β-amino acid hydrochlorides were conducted under mild conditions, without strong bases and this method is operationally simple. The stereoselective reaction was promoted by two different activation methods that lead to different stereoisomers: (1) Lewis Acid (LA) catalysis with boron trifluoride diethyl etherate and (2) Lewis Base (LB) catalysis with tetrabutylammonium difluorotriphenylsilicate. The reaction presented good diastereoselectivity with LB activation and moderate to good dr with LA catalysis. The exceptions in both protocols were imines with electron donating groups in the aromatic ring.

  17. Polycyclic alkaloids via transannular Mannich reactions

    DEFF Research Database (Denmark)

    Vital, Paulo; Hosseini, Masood; Shanmugham, M. S.

    2009-01-01

    The tricyclic compound 13, representing the framework of the cylindricine 4 and lepadiformine 5 alkaloids, was prepared in a single operation via the first example of a transannular Mannich reaction involving a macrocyclic diketoamine 12.......The tricyclic compound 13, representing the framework of the cylindricine 4 and lepadiformine 5 alkaloids, was prepared in a single operation via the first example of a transannular Mannich reaction involving a macrocyclic diketoamine 12....

  18. Direct Catalytic Asymmetric Mannich Reaction with Dithiomalonates as Excellent Mannich Donors: Organocatalytic Synthesis of (R)-Sitagliptin.

    Science.gov (United States)

    Bae, Han Yong; Kim, Mun Jong; Sim, Jae Hun; Song, Choong Eui

    2016-08-26

    In this study, dithiomalonates (DTMs) were demonstrated to be exceptionally efficient Mannich donors in terms of reactivity and stereoselectivity in cinchona-based-squaramide-catalyzed enantioselective Mannich reactions of diverse imines or α-amidosulfones as imine surrogates. Owing to the superior reactivity of DTMs as compared to conventional malonates, the catalyst loading could be reduced to 0.1 mol % without the erosion of enantioselectivity (up to 99 % ee). Furthermore, by the use of a DTM, even some highly challenging primary alkyl α-amidosulfones were smoothly converted into the desired adducts with excellent enantioselectivity (up to 97 % ee), whereas the use of a malonate or monothiomalonate resulted in no reaction under identical conditions. The synthetic utility of the chiral Mannich adducts obtained from primary alkyl substrates was highlighted by the organocatalytic, coupling-reagent-free synthesis of the antidiabetic drug (-)-(R)-sitagliptin. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Synthesis and characterization of N-Mannich based prodrugs of ciprofloxacin and norfloxacin: In vitro anthelmintic and cytotoxic evaluation

    Directory of Open Access Journals (Sweden)

    Mona Piplani

    2017-07-01

    Full Text Available Prodrugs, the inert derivatives of existing drugs have successfully contributed to the modification of their physicochemical properties. The improved antimicrobial potential due to enhanced lipophilicity of some of the synthesized prodrugs of antibacterial agents by various schemes has already been reported. In the current study, synthesis, characterization, and biological evaluation of some more lipid based prodrugs/compounds of ciprofloxacin and norfloxacin has been carried out. The synthesized prodrugs/compounds have been screened for anthelmintic activity using Indian earthworms and cytotoxic activity against human lung cancer cell lines A-549 employing sulforhodamine B (SRB assay method. The prodrugs FQF1, 6b, 6c, and 6k were found to possess promising anthelmintic activity due to improved partition coefficient. Growth of selected cells lines was found to decrease with increase in concentration of prodrugs as compared to parent drug. Prodrug, 6k having GI50 value 28.8, has been proved to be the most active among all the synthesized prodrugs. Results of present investigation reveal that some of the synthesized prodrugs/compounds were found to possess promising biological activity.

  20. Nonstabilized Azomethine Ylides in the Mannich Reaction: Synthesis of 3,3-Disubstituted Pyrrolidines, Including Oxindole Alkaloids.

    Science.gov (United States)

    Buev, Evgeny M; Moshkin, Vladimir S; Sosnovskikh, Vyacheslav Y

    2017-12-01

    Active methylene compounds react with in situ generated nonstabilized azomethine ylides via the domino Mannich reaction-dipolar cycloaddition to form 3,3-disubstituted pyrrolidines, including oxindole alkaloids. When the starting material possesses a single activated hydrogen, the reaction terminates at the Mannich base stage. The developed methodology was applied to a short and efficient synthesis of (±)-horsfiline and N-protected (±)-coerulescine.

  1. α-Halo Amides as Competent Latent Enolates: Direct Catalytic Asymmetric Mannich-Type Reaction.

    Science.gov (United States)

    Sun, Bo; Balaji, Pandur Venkatesan; Kumagai, Naoya; Shibasaki, Masakatsu

    2017-06-21

    α-Halogenated carbonyl compounds are susceptible to dehalogenation and thus largely neglected as enolate precursors in catalytic enantioselective C-C bond-forming reactions. By merging the increased stability of the α-C-halogen bond of amides and the direct enolization methodology of the designed amide, we explored a direct catalytic asymmetric Mannich-type reaction of α-halo 7-azaindoline amides with N-carbamoyl imines. All α-halo substituents, α-F, -Cl, -Br, -I amides, were tolerated to provide the Mannich-adducts in a highly stereoselective manner without undesirable dehalogenation. The diastereoselectivity switched intriguingly depending on the substitution pattern of the aromatic imines, which is ascribed to stereochemical differentiation based on the open transition-state model. Functional group interconversion of the 7-azaindoline amide moiety of the Mannich-adducts and further elaboration into a diamide without dehalogenation highlight the synthetic utility of the present protocol for accessing enantioenriched halogenated chemical entities.

  2. Asymmetric Synthesis of Amino-Bis-Pyrazolone Derivatives via an Organocatalytic Mannich Reaction.

    Science.gov (United States)

    Chauhan, Pankaj; Mahajan, Suruchi; Kaya, Uğur; Peuronen, Anssi; Rissanen, Kari; Enders, Dieter

    2017-07-07

    A new series of N-Boc ketimines derived from pyrazolin-5-ones have been used as electrophiles in asymmetric Mannich reactions with pyrazolones. The amino-bis-pyrazolone products are obtained in excellent yields and stereoselectivities by employing a very low loading of 1 mol % of a bifunctional squaramide organocatalyst. Depending on the substitution at position 4 of the pyrazolones, the new protocol allows for the generation of one or two tetrasubstituted stereocenters, including a one-pot version combing the Mannich reaction with a base-mediated halogenation.

  3. Tandem Mannich/Diels–Alder reactions for the synthesis of indole compound libraries

    DEFF Research Database (Denmark)

    Wu, Peng; Petersen, Michael Åxman; Petersen, Rico

    2016-01-01

    A tandem Mannich/Diels–Alder sequence for the synthesis of small-molecule libraries with an indolyl-octahydro-3a,6-epoxy-isoindole core structure is demonstrated in this study. Representative diversification examples based on this scaffold were performed, and a library is being produced within...

  4. Asymmetric Mannich Reaction of Aryl Methyl Ketones with Cyclic Imines Benzo[e][1,2,3]oxathiazine 2,2-Dioxides Catalyzed by Cinchona Alkaloid-based Primary Amines.

    Science.gov (United States)

    Cui, Xiao-Yu; Duan, Hui-Xin; Zhang, Yongna; Wang, You-Qing

    2016-11-07

    Aryl ketones represent problematic substrates for asymmetric Mannich reactions due to a large steric hindrance exhibited by such compound species. A highly enantioselective direct Mannich reaction of aryl methyl ketones with cyclic imine benzo[e][1,2,3]oxathiazine 2,2-dioxides could be successfully carried out utilizing a combination of cinchona alkaloid-derived primary amines with trifluoroacetic acid (TFA); the primary amines feature a superior catalytic efficacy over secondary amines with a variety of sterically hindered carbonyl compounds as substrates. The reaction proceeded well with various cyclic imines in 89-97 % ee and with various aryl methyl ketones in 85-98 % ee. Moreover, the aryl carbonyl of a Mannich product could be transformed to ketoxime, which further undergoes a Beckmann rearrangement to produce an amide compound while maintaining enantioselectivity. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Exploiting the borono-Mannich reaction in bioactive alkaloid synthesis

    OpenAIRE

    Pyne, Stephen G.; Au, Christopher W. G.; Davis, Andrew S.; Morgan, Ian Rhys; Ritthiwigrom, Thunwadee; Yazici, Arife

    2008-01-01

    We have demonstrated that the borono-Mannich reaction is a versatile and efficient reaction for the diastereoselective preparation of chiral 1,2-amino alcohols. These Mannich products are valuable starting materials as shown in this report by the synthesis of bioactive polyhydroxylated pyrrolizidine and indolizidine alkaloids. Initial studies, directed at the more complex Stemona alkaloids and using the borono-Mannich reaction on cyclic N-acyliminium ions, are encouraging, as demonstrated by ...

  6. Synthesis of Mannich bases: 2-(3-Phenylaminopropionyloxy)-benzoic acid and 3-Phenylamino-1-(2,4,6-trimethoxy-phenyl)-propan-1-one, their toxicity, ionization constant, antimicrobial and antioxidant activities.

    Science.gov (United States)

    Oloyede, Ganiyat K; Willie, Itoro E; Adeeko, Oluwakemi O

    2014-12-15

    Mannich bases 2-(3-Phenylaminopropionyloxy)-benzoic acid (A) and 3-Phenylamino-1-(2,4,6-trimethoxy-phenyl)-propan-1-one (B) were synthesized. Structures were confirmed by ultraviolet/visible and infra-red spectroscopies. The ionization constant (pKa) values at 8.3 and 8.0 reported for compounds A and B, respectively, indicated that protonation might occur at physiological pH. The LC50 values of 145,595 μg/ml (A) and 82,526 μg/ml (B) obtained from Brine shrimp lethality testing showed that both compounds were non-toxic. The two compounds possessed significant antimicrobial activity against bacterial and fungal strains; Escherichia coli, Staphylococcus aereus, Bacillus subtilis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonellae typhi, Candida albicans, Rhizopus stolonifer, Aspergillus niger and Penicillium notatum when compared with standards, gentamicin and tioconazole for bacteria and fungi, respectively. In vitro antioxidant screening by the DPPH free radical scavenging method and the scavenging effect on hydrogen peroxide showed that the compounds possessed significant antioxidant activity when compared with antioxidant standards ascorbic acid, butylated hydroxylanisole and α-tocopherol. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Single-step synthesis of a new series of meso di-Mannich bases from the cyclic aminal (2S,7R,11S,16R)-1,8,10,17-tetraazapentacyclo[8.8.1.1.8,170.2,7011,16]icosane and p-substituted phenols

    Science.gov (United States)

    2013-01-01

    Background The results presented herein show that the cyclic aminal (2S,7R,11S,16R)-1,8,10,17-tetraazapentacyclo[8.8.1.1.8,170.2,7011,16]icosane (6), derived from cis-(meso)-1,2-diaminocyclohexane and formaldehyde, is a suitable substrate for the preption of a series of cis-meso Mannich bases such as 8a-l by reaction with p-substituted phenols 7a-l in basic media. These compounds are valuable synthetic products and may find application in asymmetric catalysis. Results The products were characterized principally by NMR and IR spectroscopy. Both the benzylic and aminalic protons of the perhydrobenzimidazolidine moiety were diastereotopic due to the presence of stereogenic nitrogen centers. The occurrence of intramolecular hydrogen bonding interactions was confirmed by the broad OH stretching vibration band in the IR spectra. Vibrational spectra were calculated using B3LYP at 6-31G(d,p) level, and the calculated frequencies for the νOH vibrations were compared to those of the experimental spectra. Hydrogen bonding interactions in the solid state were observed through the X-ray crystallography of 8j. Additionally, Mulliken charges and Fukui indices for 6 were calculated as theoretical descriptors of electrophilicity. Conclusion A new series of meso Mannich bases called 4,4′-disubstituted-2,2′-{[(3aR,7aS)-2,3,3a,4,5,6,7,7a-octahydro-1H-1,3-benzimidazole-1,3-diyl]bis(methylene)} diphenols (8a-l) which are derived from cis-(meso)-1,2-diaminocyclohexane, were obtained from cyclic aminal 6. These results confirmed the behavior of 6 as an electrophilic preformed reagent in Mannich reactions in basic media. PMID:23758899

  8. Direct Catalytic Asymmetric Mannich-Type Reaction en Route to α-Hydroxy-β-amino Acid Derivatives.

    Science.gov (United States)

    Sun, Bo; Pluta, Roman; Kumagai, Naoya; Shibasaki, Masakatsu

    2018-02-02

    A direct catalytic Mannich-type reaction of α-oxygen-functionalized amides was achieved. The use of 7-azaindoline amide was crucial to facilitate direct enolization and subsequent stereoselective addition to imines in a cooperative catalytic system comprising a soft Lewis acid and Brønsted base. The operationally simple room-temperature protocol furnished a syn-Mannich adduct with high stereoselectivity. Divergent functional group transformation of the amide moiety of the product allowed for expeditious access to enantioenriched syn-configured α-hydroxy-β-amino carboxylic acid derivatives, highlighting the synthetic utility of the present catalysis.

  9. An asymmetric acetate-Mannich reaction of chiral isatin derived ketimines and its applications.

    Science.gov (United States)

    Hajra, Saumen; Bhosale, Suhas Shivajirao; Hazra, Atanu

    2017-11-07

    A highly efficient TMSOTf-mediated asymmetric acetate-Mannich reaction of isatin derived tert-butylsulfinyl ketimines and S-phenyl thioacetate was developed to afford the direct synthesis of indole-based β 3,3 -amino acid thioester with excellent selectivity (dr > 98 : 2). Syntheses of (+)-AG-041R and 3-aminopyrroloindoline have been accomplished utilizing the developed method.

  10. Direct Catalytic Asymmetric Mannich-Type Reaction of Alkylamides.

    Science.gov (United States)

    Arteaga, Fernando Arteaga; Liu, Zijian; Brewitz, Lennart; Chen, Jianyang; Sun, Bo; Kumagai, Naoya; Shibasaki, Masakatsu

    2016-05-20

    Direct enolate formation coupled with subsequent enantioselective C-C bond formation remains a topic of intense interest in asymmetric catalysis. This methodology is achieved even with low acidic amides without an electron-withdrawing group at the α-position in the context of a Mannich-type reaction. Acetate-, propionate-, and butyrate-type 7-azaindoline amides served as enolate precursors to afford the desired Mannich adducts with high stereoselectivity, and ligand-enabled diastereo-divergency provided access to both anti/syn diastereomers. The facile transformation of the amide moiety ensures the synthetic utility of the Mannich adducts.

  11. Chemoselective Boron-Catalyzed Nucleophilic Activation of Carboxylic Acids for Mannich-Type Reactions.

    Science.gov (United States)

    Morita, Yuya; Yamamoto, Tomohiro; Nagai, Hideoki; Shimizu, Yohei; Kanai, Motomu

    2015-06-10

    The carboxyl group (COOH) is an omnipresent functional group in organic molecules, and its direct catalytic activation represents an attractive synthetic method. Herein, we describe the first example of a direct catalytic nucleophilic activation of carboxylic acids with BH3·SMe2, after which the acids are able to act as carbon nucleophiles, i.e. enolates, in Mannich-type reactions. This reaction proceeds with a mild organic base (DBU) and exhibits high levels of functional group tolerance. The boron catalyst is highly chemoselective toward the COOH group, even in the presence of other carbonyl moieties, such as amides, esters, or ketones. Furthermore, this catalytic method can be extended to highly enantioselective Mannich-type reactions by using a (R)-3,3'-I2-BINOL-substituted boron catalyst.

  12. Proline-catalysed Mannich reactions of acetaldehyde.

    Science.gov (United States)

    Yang, Jung Woon; Chandler, Carley; Stadler, Michael; Kampen, Daniela; List, Benjamin

    2008-03-27

    Small organic molecules recently emerged as a third class of broadly useful asymmetric catalysts that direct reactions to yield predominantly one chiral product, complementing enzymes and metal complexes. For instance, the amino acid proline and its derivatives are useful for the catalytic activation of carbonyl compounds via nucleophilic enamine intermediates. Several important carbon-carbon bond-forming reactions, including the Mannich reaction, have been developed using this approach, all of which are useful for making chiral, biologically relevant compounds. Remarkably, despite attempts, the simplest of all nucleophiles, acetaldehyde, could not be used in this way. Here we show that acetaldehyde is a powerful nucleophile in asymmetric, proline-catalysed Mannich reactions with N-tert-butoxycarbonyl (N-Boc)-imines, yielding beta-amino aldehydes with extremely high enantioselectivities-desirable products as drug intermediates and in the synthesis of other biologically active molecules. Although acetaldehyde has been used as a nucleophile in reactions with biological catalysts such as aldolases and thiamine-dependent enzymes, and has also been employed indirectly, its use as an inexpensive and versatile two-carbon nucleophile in asymmetric, small-molecule catalysis will find many practical applications.

  13. Protease-catalysed Direct Asymmetric Mannich Reaction in Organic Solvent

    Science.gov (United States)

    Xue, Yang; Li, Ling-Po; He, Yan-Hong; Guan, Zhi

    2012-10-01

    We reported the first enzyme-catalysed, direct, three-component asymmetric Mannich reaction using protease type XIV from Streptomyces griseus (SGP) in acetonitrile. Yields of up to 92% with enantioselectivities of up to 88% e.e. and diastereoselectivities of up to 92:8 (syn:anti) were achieved under the optimised conditions. This enzyme's catalytic promiscuity expands the application of this biocatalyst and provides a potential alternative method for asymmetric Mannich reactions.

  14. Synthesis of 6a,7b-dihydroxyvouacapan-17b-oic acid derivatives. Part IV: mannich base derivatives and its activities on the electrically stimulated Guinea-pig ileum preparation

    Directory of Open Access Journals (Sweden)

    Belinelo Valdenir J.

    2002-01-01

    Full Text Available The furanditerpene 6alpha,7beta-dihydroxyvouacapan-17beta-oic acid (ADV, 1, isolated from Pterodon polygalaeflorus Benth fruits, presents analgesic activity in current rodent experimental models. With the aim to gather data for biological studies it were obtained six new amide derivatives substituted in the furan ring with alkylamine groups, prepared by the Mannich reaction with preformed iminium salts. These derivatives were evaluated in a preliminary in vitro pharmacological test. Structures were determined by spectroscopic data of IR, ¹H and 13C NMR.

  15. Reação de Mannich: Metodologia Clássica na Formação de Ligação Carbono-Carbono

    Directory of Open Access Journals (Sweden)

    João Francisco Allochio Filho

    2013-08-01

    Full Text Available A reação de Mannich é um método clássico para a preparação de b-aminocetonas e aldeídos, conhecidos como base de Mannich, sendo assim uma das reações mais importantes da química orgânica. Os adutos de Mannich possuem particular interesse devido às suas atividades biológicas, uso como intermediários sintéticos e precursores importantes de produtos farmacêuticos importantes. Nesse contexto, várias elegantes reações estereosseletivas de a-aminoalquilação foram desenvolvidas.

  16. Scalable and versatile graphene functionalized with the Mannich condensate.

    Science.gov (United States)

    Liao, Ruijuan; Tang, Zhenghai; Lin, Tengfei; Guo, Baochun

    2013-03-01

    The functionalized graphene (JTPG) is fabricated by chemical conversion of graphene oxide (GO), using tea polyphenols (TP) as the reducer and stabilizer, followed by further derivatization through the Mannich reaction between the pyrogallol groups on TP and Jeffamine M-2070. JTPG exhibits solubility in a broad spectrum of solvents, long-term stability and single-layered dispersion in water and organic solvents, which are substantiated by AFM, TEM, and XRD. The paper-like JTPG hybrids prepared by vacuum-assisted filtration exhibits an unusual combination of high toughness (tensile strength of ~275 MPa and break strain of ~8%) and high electrical conductivity (~700 S/m). Still, JTPG is revealed to be very promising in the fabrication of polymer/graphene composites due to the excellent solubility in the solvent with low boiling point and low toxicity. Accordingly, as an example, nitrile rubber/JTPG composites are fabricated by the solution compounding in acetone. The resulted composite shows low threshold percolation at 0.23 vol.% of graphene. The versatilities both in dispersibility and performance, together with the scalable process of JTPG, enable a new way to scale up the fabrication of the graphene-based polymer composites or hybrids with high performance.

  17. List-Barbas-Mannich reaction catalyzed by modularly designed organocatalysts.

    Science.gov (United States)

    Perera, Sandun; Sinha, Debarshi; Rana, Nirmal K; Trieu-Do, Van; Zhao, John Cong-Gui

    2013-11-01

    The List-Barbas-Mannich reaction of ethyl (p-methoxyphenylimino)acetate (p-methoxyphenyl = PMP) with unmodified aldehydes or ketones catalyzed by modularly designed organocatalysts (MDOs) that are self-assembled from proline and cinchona alkaloid thioureas (such as a quinidine-derived thiourea) produces the corresponding γ-oxo-α-amino acid derivatives in high yields and excellent stereoselectivities. No solvent is necessary for this reaction. Aldehydes are especially good substrates for this reaction: The reaction takes only a few minutes to yield the corresponding List-Barbas-Mannich products in excellent dr (up to >99:1) and ee values (up to >99% ee).

  18. A Disulfonimide Catalyst for Highly Enantioselective Mukaiyama-Mannich Reaction.

    Science.gov (United States)

    Zhou, Fengtao; Yamamoto, Hisashi

    2016-10-07

    A new BINOL-derived chiral disulfonimide has been developed by introducing 4-methyl-3,5-dinitrophenyl substituents at its 3- and 3'-positions. This chiral disulfonimide catalyst displays high catalytic efficacy toward the asymmetric Mukaiyama-Mannich reaction of imines with ketene silyl acetals leading to β-amino acid esters in good yields (up to 99%) with high diastereoselectivities (syn/anti up to 97:3) and enantioselectivities (up to 98% ee). The long-standing problem of the chiral phosphoric acid-catalyzed asymmetric Mukaiyama-Mannich reaction that requires a 2-hydroxyphenyl moiety was solved by this disulfonimide catalyst.

  19. Organocatalyzed Enantioselective Direct Mannich Reaction of α-Styrylacetates.

    Science.gov (United States)

    Guang, Jie; Rout, Saroj; Bihani, Manisha; Larson, Ariel J; Arman, Hadi D; Zhao, John C-G

    2016-06-03

    An organocatalyzed direct Mannich reaction of unactivated α-styrylacetates was realized for the first time. By using a quinidine-derived C6'-urea catalyst, the direct Mannich reaction of α-styrylacetates and N-tosylimines gave the desired β-amino esters in high yields, diastereoselectivities, and ee values. The reaction provides a highly stereoselective (up to 96:4 dr and 97% ee) and the most straightforward synthesis of functionalized N-tosylated β-amino esters. The products can be used as precursors for the highly selective synthesis of tetrahydrofuran derivatives.

  20. Three-Component Asymmetric Mannich Reaction Catalyzed by a Lewis Acid with Rhodium-Centered Chirality.

    Science.gov (United States)

    Feng, Lihe; Dai, Xuemei; Meggers, Eric; Gong, Lei

    2017-05-04

    A highly efficient direct asymmetric three-component Mannich reaction of an N-acylpyrazole, an aldehyde and a primary or secondary amine, was enabled by a rhodium-based Lewis-acid catalyst with metal-centered chirality. Excellent enantioselectivities were achieved for a variety of substrates at a typical catalyst loading of merely 0.5 mol % (23 examples, up to 98 % ee). © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. The tandem Mannich-electrophilic amination reaction: a versatile platform for fluorescent probing and labeling.

    Science.gov (United States)

    Sączewski, Jarosław; Hinc, Krzysztof; Obuchowski, Michał; Gdaniec, Maria

    2013-08-26

    Tandem fluorogenic reaction: A new platform for the direct, selective and sensitive detection of formaldehyde and/or secondary aliphatic amines, based on a tandem Mannich-electrophilic amination reaction, is described. Biological applications of hydrophilic, water-soluble fluorescent 2,2-dialkyl-2,3-dihydro-[1,2,4]triazolo[4,3-a]pyridin-2-ium-8-carboxylates (Safarinium P probes) are exemplified by labeling of the amine-containing Ac-AKF-NH2 peptide and Bacillus subtilis spores in aqueous solution. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Study of 2-aminoquinolin-4(1H)-one under Mannich and retro-Mannich reaction

    OpenAIRE

    Funk, Petr; Motyka, Kamil; Soural, Miroslav; Malon, Michal; Koshino, Hiroyuki; Kusz, Joachim; Hlavac, Jan

    2017-01-01

    2-Aminoquinolin-4(1H)-one was reacted with various primary/secondary amines and paraformaldehyde under Mannich reaction conditions. In the case of secondary amines, the reaction in N,N-dimethylformamide yielded expected Mannich products accompanied with 3,3'-methylenebis(2-aminoquinolin-4(1H)-one). Except these main products, the pyrimido[4,5-b]quinolin-5-one derivative was also identified as co-product. The reaction with primary amines led to the formation of pyrimido[4,5-b]quinolin-5-ones. ...

  3. Diastereoselective three-component vinylogous Mannich reaction of nitrogen heterocycles, acyl/sulfonyl chlorides, and silyloxyfurans/pyrroles.

    Science.gov (United States)

    Janody, Simon; Hermange, Philippe; Retailleau, Pascal; Thierry, Josiane; Dodd, Robert H

    2014-06-20

    A one-step, 3-component vinylogous Mannich reaction of trimethylsilyloxyfuran or N-protected tert-butyldimethylsilyloxypyrrole with a variety of nitrogen-containing heterocycles in the presence of diverse electrophiles is described. The reaction products were generally obtained in high yields and as a single diastereoisomer having the (R*,R*) relative configuration based on crystallographic studies of several derivatives. Several azaheterocycles were successfully used for this reaction, such as isoquinolines, quinoline, phenanthridine, quinazoline, phthalazine, and β-carboline, and electrophiles included acetyl chloride, methyl chloroformate, methyl chloromalonate, 2-bromobutanoyl chloride, and arylsulfonyl chlorides. The products of the vinylogous Mannich reactions were subjected to further transformations, leading to highly functionalized and stereochemically defined tetracyclic derivatives that are valuable building blocks for the preparation of natural products or medicinal agents.

  4. Mannich reaction: A versatile and convenient approach to bioactive ...

    Indian Academy of Sciences (India)

    ent analogue, against HeLa cell line. The studies con- firm the fact that the presence of Mannich side chain improves the activity of an existing bioactive molecule. The semi-synthetic lactone analogue 44 obtained from the natural product 6α,7β-dihydroxyvouacapan-. 17β-oic acid, showed better anticancer activity than ...

  5. The Oxidative Mannich Reaction Catalyzed by Dirhodium Caprolactamate

    Science.gov (United States)

    Catino, Arthur J.; Nichols, Jason M.; Nettles, Brian J.; Doyle, Michael P.

    2008-01-01

    Dirhodium caprolactamate [Rh2(cap)4] is a highly effective catalyst for the oxidative Mannich reaction. The reaction proceeds via C-H oxidation of a tertiary amine followed by nucleophilic capture. This green transformation is conducted in protic solvent using inexpensive T-HYDRO® (70% t–BuOOH in water). Synthetically valuable γ-aminoalkyl-butenolides are obtained. PMID:16637627

  6. Enol esters: versatile substrates for Mannich-type multicomponent reactions.

    Science.gov (United States)

    Isambert, Nicolas; Cruz, Montse; Arévalo, María José; Gómez, Elena; Lavilla, Rodolfo

    2007-10-11

    The interaction of cyclic enol esters with diversely substituted anilines and ethyl glyoxalate yields, under Sc(OTf)3 catalysis, disubstituted N-aryl lactams in a multicomponent reaction. The protocol allows access to the trans stereoisomers after an epimerization of the initial mixture in which the cis isomers predominate. Vinyl acetate yields quinoline derivatives, whereas isopropenyl acetate leads to the corresponding Mannich adducts.

  7. Study of 2-aminoquinolin-4(1H)-one under Mannich and retro-Mannich reaction.

    Science.gov (United States)

    Funk, Petr; Motyka, Kamil; Soural, Miroslav; Malon, Michal; Koshino, Hiroyuki; Kusz, Joachim; Hlavac, Jan

    2017-01-01

    2-Aminoquinolin-4(1H)-one was reacted with various primary/secondary amines and paraformaldehyde under Mannich reaction conditions. In the case of secondary amines, the reaction in N,N-dimethylformamide yielded expected Mannich products accompanied with 3,3'-methylenebis(2-aminoquinolin-4(1H)-one). Except these main products, the pyrimido[4,5-b]quinolin-5-one derivative was also identified as co-product. The reaction with primary amines led to the formation of pyrimido[4,5-b]quinolin-5-ones. The Mannich reaction products were thermally unstable and afforded a mixture of bis-(2-aminoquinolin-4(1H)-one) and tris-(2-aminoquinolin-4(1H)-one) derivative, probably via reactive methylene species. This retro-Mannich reaction was tested in reaction with indole and thiophenole as nucleophilles, and appropriate conjugates were formed. The mechanism of above discussed reactions in which 2-aminoquinolinone displays the nucleophilicity on C3 carbon as well as N2 nitrogen is discussed.

  8. Study of 2-aminoquinolin-4(1H-one under Mannich and retro-Mannich reaction.

    Directory of Open Access Journals (Sweden)

    Petr Funk

    Full Text Available 2-Aminoquinolin-4(1H-one was reacted with various primary/secondary amines and paraformaldehyde under Mannich reaction conditions. In the case of secondary amines, the reaction in N,N-dimethylformamide yielded expected Mannich products accompanied with 3,3'-methylenebis(2-aminoquinolin-4(1H-one. Except these main products, the pyrimido[4,5-b]quinolin-5-one derivative was also identified as co-product. The reaction with primary amines led to the formation of pyrimido[4,5-b]quinolin-5-ones. The Mannich reaction products were thermally unstable and afforded a mixture of bis-(2-aminoquinolin-4(1H-one and tris-(2-aminoquinolin-4(1H-one derivative, probably via reactive methylene species. This retro-Mannich reaction was tested in reaction with indole and thiophenole as nucleophilles, and appropriate conjugates were formed. The mechanism of above discussed reactions in which 2-aminoquinolinone displays the nucleophilicity on C3 carbon as well as N2 nitrogen is discussed.

  9. Multicomponent Mannich Reactions Using Boron Enolates Derived from Diazo Esters and 9-BBN

    OpenAIRE

    Luan, Yi; Schaus, Scott E.

    2011-01-01

    Diazo esters, arylboranes and carbamoyl imines undergo a 3-component Mannich condensation reaction. Catalyzed by Cu(II) salts, the reaction affords the corresponding isocyanate Mannich product; one that can be easily trapped in situ by other nucleophiles. The Mannich condensation corresponds to an α,α-disubstituted enolate addition to imines. The reaction was rendered asymmetric using the (-)-phenylmenthol ester in good yield and selectivities.

  10. Preparation of dichlorvos-protein complete antigen by Mannich-type reaction

    Science.gov (United States)

    Feng, Qianqian; Xu, Ying; Zhou, Youxiang; Lu, Liang; Chen, Fusheng; Wang, Xiaohong

    2010-08-01

    Dichlorvos (DDVP) residues have been linked to substantial adverse health effects on several organ systems. To ensure food safety, rapid and low-cost immunological methods must be applied to detect DDVP residues in food. In immunological methods, a key step is coupling DDVP to carrier proteins to obtain a complete antigen due to DDVP being hapten. In the current research, DDVP was coupled with cationized bovine serum albumin (cBSA) using a method based on Mannich-type reaction. A DDVP-cBSA conjugate, with a molar ratio of 40:1 DDVP to cBSA was synthesized. The cationized proteins and their conjugates were identified by UV-Vis and FT-IR spectra, which showed the characteristic bands of the ethylenediamine group and DDVP, respectively. BALB/c mice were immunized with DDVP-cBSA. One hybridoma cell line secreted anti-DDVP monoclonal antibody (Mab) that had high sensitivity and specificity for DDVP. Competitive ELISA identified an IC50 of 600 ng/mL and a limit of detection of 1 ng/mL in aqueous solution. The Mab had some cross-reactivity with phosmet, but no cross-reactivity with chlorothalonil and procymidone. We also detected a trace of DDVP in waste water. In conclusion the Mannich-type reaction couples DDVP to protein, yielding an antigen for the production of Mab to detect residual DDVP in the environment.

  11. Mannich reaction of polysaccharides: Xylan functionalization in aqueous basic medium.

    Science.gov (United States)

    Ünlü, Cüneyt H; Kutlu, Meltem; Atıcı, Oya Galioğlu

    2015-01-01

    In this study modification of xylan via Mannich reaction in aqueous basic solution to obtain dimethylaminomethylated products and characterization of modified xylan were examined. Components were xylan (obtained from corn cob and used without modification) as active hydrogen containing compound, formaldehyde as carbonyl compound having no α-hydrogen and dimethylamine. Mannich reaction was used with different parameters such as component concentration, reaction temperature, and time. The highest modification was observed about 35°C with a nitrogen content of 4.6% by weight indicating successive modification. Both 1D and 2D NMR measurements displayed new signals related with aminomethyl groups. Spectral characterizations indicated that aminomethylation took place on oxygen sites. Moreover modified xylan could form film while xylan could not without an auxiliary agent. Antimicrobial activity tests indicated that modified xylan acted as a bacteriostatic material. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Iron-Catalyzed Asymmetric Nitro-Mannich Reaction.

    Science.gov (United States)

    Dudek, Agata; Mlynarski, Jacek

    2017-10-20

    The first enantioselective addition of nitroalkanes to imines (nitro-Mannich reaction), mediated by an iron(II) catalyst assembled by a hindered hydroxyethyl-pybox ligand, is described. This valuable carbon-carbon bond-forming reaction proceeds smoothly at room temperature to afford enantioenriched β-nitro amines in good yields and high enantioselectivity, up to 98% with unprecedentedly low iron catalyst loading (5 mol %).

  13. Promotion of a Ti-Mediated Mannich Reaction by a Proton Source.

    Science.gov (United States)

    Limanto, John; Yoshikawa, Naoki; Reamer, Robert A; Tan, Lushi; Brunskill, Andrew; Reibarkh, Mikhail

    2016-01-15

    Low temperature NMR studies revealed that a diastereoselective Mannich reaction between a phenyl oxazolidone-derived titanium enolate and an aromatic aldimine was found to occur only after introduction of a proton source. While various protic additives could be used to promote the transformation, the best results were obtained using AcOH to afford the corresponding Mannich products in high diastereoselectivities and yields.

  14. From Lead to Drug Utilizing a Mannich Reaction: The Topotecan Story.

    Science.gov (United States)

    Bracher, Franz; Tremmel, Tim

    2017-07-01

    Natural products are a rich source of bioactive compounds, and numerous natural compounds have found application in cancer chemotherapy. However, unfavorable physicochemical properties often prevent the use of the original natural product as a drug. A prominent example is camptothecin from the Chinese tree Camptotheca acuminata, which shows extraordinary cytotoxic activity based on a specific molecular mode of action (inhibition of human topoisomerase I). Due to its extremely poor solubility, the original natural product cannot be used as a drug. The marketed drug topotecan was developed from this lead structure by semi-synthesis utilizing a Mannich aminomethylation as the crucial step. In this review, the long-distance run leading to this drug and further perspectives are summarized. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Geminal Brønsted Acid Ionic Liquids as Catalysts for the Mannich Reaction in Water

    Directory of Open Access Journals (Sweden)

    Leqin He

    2014-05-01

    Full Text Available Quaternary ammonium geminal Brønsted acid ionic liquids (GBAILs based on zwitterionic 1,2-bis[N-methyl-N-(3-sulfopropyl-alkylammonium]ethane (where the carbon number of the alkyl chain is 4, 8, 10, 12, 14, 16, or 18 and p-toluenesulfonic acid monohydrate were synthesized. The catalytic ionic liquids were applied in three-component Mannich reactions with an aldehyde, ketone, and amine at 25 °C in water. The effects of the type and amount of catalyst and reaction time as well as the scope of the reaction were investigated. Results showed that GBAIL-C14 has excellent catalytic activity and fair reusability. The catalytic procedure was simple, and the catalyst could be recycled seven times via a simple separation process without noticeable decreases in catalytic activity.

  16. Geminal Brønsted acid ionic liquids as catalysts for the Mannich reaction in water.

    Science.gov (United States)

    He, Leqin; Qin, Shenjun; Chang, Tao; Sun, Yuzhuang; Zhao, Jiquan

    2014-05-15

    Quaternary ammonium geminal Brønsted acid ionic liquids (GBAILs) based on zwitterionic 1,2-bis[N-methyl-N-(3-sulfopropyl)-alkylammonium]ethane (where the carbon number of the alkyl chain is 4, 8, 10, 12, 14, 16, or 18) and p-toluenesulfonic acid monohydrate were synthesized. The catalytic ionic liquids were applied in three-component Mannich reactions with an aldehyde, ketone, and amine at 25 °C in water. The effects of the type and amount of catalyst and reaction time as well as the scope of the reaction were investigated. Results showed that GBAIL-C14 has excellent catalytic activity and fair reusability. The catalytic procedure was simple, and the catalyst could be recycled seven times via a simple separation process without noticeable decreases in catalytic activity.

  17. Asymmetric vinylogous Mannich reactions: a versatile approach to functionalized heterocycles.

    Science.gov (United States)

    Ruan, Shu-Tang; Luo, Jie-Min; Du, Yu; Huang, Pei-Qiang

    2011-09-16

    Asymmetric vinylogous Mannich reaction (VMR) of 2-(tert-butyldimethylsilyloxy)furan (TBSOF, 1) with (R(S))- or (S(S))-t-BS-imines (3) furnished 5-aminoalkylbutenolides 7a-k in 75-87% yields with anti/syn ratios ranging from 75:25 to 97:3. Butenolides 7a-f,k were readily converted into substituted lactones 8 and 5 and 6-substituted 5-hydroxypiperidin-2-ones 11a-g, which are, in turn, key intermediates for the synthesis of many bioactive compounds. © 2011 American Chemical Society

  18. Direct Asymmetric Vinylogous and Bisvinylogous Mannich-Type Reaction Catalyzed by a Copper(I) Complex.

    Science.gov (United States)

    Zhang, Hai-Jun; Shi, Chang-Yun; Zhong, Feng; Yin, Liang

    2017-02-15

    A direct catalytic asymmetric vinylogous Mannich-type reaction has been disclosed in good yield, excellent regio-, diastereo- and enantioselectivity. The key to control the regioselectivity is the combination of a bulky N-acylpyrazole and a bulky bisphosphine ligand. The catalytic system was extended to a bisvinylogous Mannich-type reaction by changing the ligand. The synthetic utility of the vinylogous products was demonstrated by several transformations.

  19. Chiral Phosphoric Acid Catalyzed Diastereo- and Enantioselective Mannich-Type Reaction between Enamides and Thiazolones.

    Science.gov (United States)

    Kikuchi, Jun; Momiyama, Norie; Terada, Masahiro

    2016-06-03

    An enantioselective Mannich-type reaction between enamides, serving as aliphatic imine equivalents, and thiazolones or an azlactone, serving as α-amino acid derived pronucleophiles, was investigated using a chiral phosphoric acid catalyst. By using thiazolones, Mannich adducts with a tetrasubstituted chiral carbon center at the α-position and an aliphatic substituent at the β-position were efficiently obtained with high diastereo- and enantioselectivities.

  20. The development of a one-pot 1,4-addition/nitro-Mannich reaction

    OpenAIRE

    Mills, M. R.

    2010-01-01

    The introduction of this thesis reviews the three areas of importance to the research carried out. These are the nitro-Mannich reaction, the conjugate addition of nucleophiles to nitro-alkenes and the diastereoselectivity of electrophilic additions to substrates bearing an α-stereocentre. The Results and Discussion details the research carried out into the development of a one-pot 1,4-addition/nitro-Mannich reaction. Initially the research focused on triggering the reaction ...

  1. Comportement nucléophile des N-arylhydrazones: réaction de Mannich et applications.

    OpenAIRE

    Michaut, Valérie

    2003-01-01

    The first chapter examines the valuation of Mannich adducts, exploration nucleophiles compatible with the conditions developed previously and the study of reduction of hydrazone after Mannich reaction. Chapter 2 is devoted to the study of aminoalkylation hydrazones. Of solvent-free reaction conditions were developed for the Mannich reaction of hydrazones. The third chapter presents the aza-aldol reaction of hydrazones. A new aza-aldol reaction of N-phenyl cétohydrazones has been developed. Ch...

  2. Brønsted acid-catalyzed Mannich reaction through dual activation of aldehydes and N-Boc-imines.

    Science.gov (United States)

    Kano, Taichi; Aota, Yusuke; Asakawa, Daisuke; Maruoka, Keiji

    2015-11-28

    In the presence of a Brønsted acid catalyst, both aldehydes and N-Boc-aminals were converted to enecarbamates and N-Boc-iminium salts as activated nucleophiles and electrophiles, respectively, giving unprecedented Mannich adducts. The asymmetric variant of the present Mannich reaction has also been demonstrated with a chiral phosphoric acid catalyst.

  3. Influence of the Organocatalyst in the Aldol/Mannich-Type Product Selectivities in C−C Bond Forming Reactions

    NARCIS (Netherlands)

    Dominguez de Maria, Pablo; Bracco, Paula; Castelhano, Luiz Fernando; Bargeman, Gerrald

    2011-01-01

    Several organocatalysts were tested in the cross condensation of isobutyraldehyde and acetone. Formation of aldol-type and Mannich-type (“aldol condensation”) products was assessed, and Aldol/Mannich proportion studied under several reaction conditions and at different conversions. Organocatalysts

  4. Competition versus Cooperation in Catalytic Hydrogelators for anti-Selective Mannich Reaction.

    Science.gov (United States)

    Singh, Nishant; Escuder, Beatriu

    2017-07-21

    Chemical systems find similarities in different sociological and biological processes, in which the entities compete or cooperate for a favorable outcome. The structural and functional adaptations leading to emergent properties, especially in catalysis, are based on factors such as abundance of substrates, stability of the transition state, and structural/functional attributes of catalysts. Proline and acid groups appended to catalytic fibers of two self-sorting hydrogelators compete for the Mannich reaction between aniline, benzaldehyde, and cyclohexanone to give low overall selectivity (anti/syn 77:23). In a sol-gel system of the same molecules, on the other hand, the soluble acid appended molecules tend to cooperate with the fibers of proline-appended catalyst to give improved selectivity (anti/syn 95:5). The available options for the catalytic molecules are to carry out the reaction independently or in cooperation. However, these options are chosen based on the efficiency, selectivity, and mobility of catalysts as a result of their abilities to self-assemble. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Glycerol as an Efficient Medium for the Petasis Borono–Mannich Reaction

    Science.gov (United States)

    Rosholm, Tomi; Gois, Pedro M P; Franzen, Robert; Candeias, Nuno R

    2015-01-01

    The multicomponent Petasis borono–Mannich (PBM) reaction is a useful tool for the preparation of complex molecules in a single step from boronic acids, aldehydes/ketones, and amines. Here, we describe the use of glycerol in the PBM reaction of salicylaldehydes or 2-pyridinecarbaldehyde with several boronic acids and secondary amines. From these readily available starting materials, alkylaminophenols, 2-substituted pyridines, and 2H-chromenes were prepared in reasonable to good yields. Glycerol was compared with other solvents, and in some cases, it provided the reaction product in higher yield. Crude glycerol, as generated by the biodiesel industry, was evaluated and found to be a suitable solvent for the PBM reaction, successfully expanding the potential use of this industry by-product. Based on density functional theory (DFT) calculations and the obtained experimental results, the involvement of glycerol-derived boronic esters in the reaction mechanism is suggested to be competitive with the free boronic acid pathway. Similar Gibbs free energies for the aryl migration from the boronate species to the iminium were determined for both mechanisms. PMID:25861569

  6. Glycerol as an efficient medium for the petasis borono-mannich reaction.

    Science.gov (United States)

    Rosholm, Tomi; Gois, Pedro M P; Franzen, Robert; Candeias, Nuno R

    2015-02-01

    The multicomponent Petasis borono-Mannich (PBM) reaction is a useful tool for the preparation of complex molecules in a single step from boronic acids, aldehydes/ketones, and amines. Here, we describe the use of glycerol in the PBM reaction of salicylaldehydes or 2-pyridinecarbaldehyde with several boronic acids and secondary amines. From these readily available starting materials, alkylaminophenols, 2-substituted pyridines, and 2H-chromenes were prepared in reasonable to good yields. Glycerol was compared with other solvents, and in some cases, it provided the reaction product in higher yield. Crude glycerol, as generated by the biodiesel industry, was evaluated and found to be a suitable solvent for the PBM reaction, successfully expanding the potential use of this industry by-product. Based on density functional theory (DFT) calculations and the obtained experimental results, the involvement of glycerol-derived boronic esters in the reaction mechanism is suggested to be competitive with the free boronic acid pathway. Similar Gibbs free energies for the aryl migration from the boronate species to the iminium were determined for both mechanisms.

  7. Direct Catalytic Asymmetric Mannich-Type Reaction of α- and β-Fluorinated Amides.

    Science.gov (United States)

    Brewitz, Lennart; Arteaga, Fernando Arteaga; Yin, Liang; Alagiri, Kaliyamoorthy; Kumagai, Naoya; Shibasaki, Masakatsu

    2015-12-23

    The last two decades have witnessed the emergence of direct enolization protocols providing atom-economical and operationally simple methods to use enolates for stereoselective C-C bond-forming reactions, eliminating the inherent drawback of the preformation of enolates using stoichiometric amounts of reagents. In its infancy, direct enolization relied heavily on the intrinsic acidity of the latent enolates, and the reaction scope was limited to readily enolizable ketones and aldehydes. Recent advances in this field enabled the exploitation of carboxylic acid derivatives for direct enolization, offering expeditious access to synthetically versatile chiral building blocks. Despite the growing demand for enantioenriched fluorine-containing small molecules, α- and β-fluorinated carbonyl compounds have been neglected in direct enolization chemistry because of the competing and dominating defluorination pathway. Herein we present a comprehensive study on direct and highly stereoselective Mannich-type reactions of α- and β-fluorine-functionalized 7-azaindoline amides that rely on a soft Lewis acid/hard Brønsted base cooperative catalytic system to guarantee an efficient enolization while suppressing undesired defluorination. This protocol contributes to provide a series of fluorinated analogs of enantioenriched β-amino acids for medicinal chemistry.

  8. Catalytic Asymmetric Mannich Reaction with N-Carbamoyl Imine Surrogates of Formaldehyde and Glyoxylate.

    Science.gov (United States)

    You, Yang'en; Zhang, Long; Cui, Linfeng; Mi, Xueling; Luo, Sanzhong

    2017-10-23

    N,O-acetals (NOAcs) were developed as bench stable surrogates for N-carbamoyl, (Boc, Cbz and Fmoc) formaldehyde and glyoxylate imines in asymmetric Mannich reactions. The NOAcs can be directly utilized in the chiral primary amine catalyzed Mannich reactions of both acyclic and cyclic β-ketocarbonyls with high yields and excellent stereoselectivity. The current reaction offers a straightforward approach in the asymmetric synthesis of α- or β-amino carbonyls bearing chiral quaternary centers in a practical and highly stereocontrolled manner. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Synthesis of the Azepinobisindole Alkaloid Iheyamine A Enabled by a Cross-Mannich Reaction.

    Science.gov (United States)

    Lindsay, Ashley C; Leung, Ivanhoe K H; Sperry, Jonathan

    2016-10-05

    The total synthesis of the azepinobisindole alkaloid iheyamine A is described. The successful strategy hinged on an intermolecular cross-Mannich reaction between 5-methoxy-3-acetoxyindole and a protected tryptamine to access an unsymmetrical 2,2'-bisindole, which was subsequently converted into iheyamine A via a deep-blue 3-indolone intermediate. VT 1 H NMR infers that iheyamine A exists as a mixture of tautomers that undergo intermediate chemical exchange on the NMR time scale. The intermolecular cross-Mannich reaction described herein is a viable alternative to metal-catalyzed cross-coupling strategies commonly employed to access 2,2'-bisindoles.

  10. Reactions of coordinated hydroxymethylphosphines with NH-functional amines: the phosphorus lone pair is crucial for the phosphorus Mannich reaction.

    Science.gov (United States)

    Swor, Charles D; Hanson, Kyle R; Zakharov, Lev N; Tyler, David R

    2011-09-14

    Non-coordinated hydroxymethylphosphines react readily with primary and secondary amines by the phosphorus Mannich reaction. To determine if this reactivity can be used to synthesize phosphine macrocycles, trans-Fe(DHMPE)(2)Cl(2) (DHMPE = 1,2-bis(dihydroxymethylphosphino)ethane) was prepared and reacted with various amines. However, no phosphorus Mannich reactivity was observed. In order to understand why no reactions occurred, the Mannich reactivity of the borane-coordinated hydroxymethylphosphines DHMPE·2BH(3) and Ph(2)PCH(2)OH·BH(3) was investigated. These borane-coordinated phosphines also did not undergo the phosphorus Mannich reaction. These results suggest that the lone pair of electrons on the phosphorus atom is essential for the phosphorus Mannich reaction to occur, and therefore it is not possible to use this reaction in a templated synthesis of phosphine macrocycles. It is speculated that the mechanism of the phosphorus Mannich reaction may involve a methylenephosphonium intermediate, analogous to an iminium in the standard Mannich reaction. X-ray crystal structures of trans-Fe(DHMPE)(2)Cl(2) and DHMPE·2BH(3) are also presented. Both crystal structures display an extended hydrogen-bonding network in the solid state. This journal is © The Royal Society of Chemistry 2011

  11. A chiral Brønsted acid-catalyzed highly enantioselective Mannich-type reaction of α-diazo esters with in situ generated N-acyl ketimines.

    Science.gov (United States)

    Unhale, Rajshekhar A; Sadhu, Milon M; Ray, Sumit K; Biswas, Rayhan G; Singh, Vinod K

    2018-04-03

    A chiral phosphoric acid-catalyzed asymmetric Mannich-type reaction of α-diazo esters with in situ generated N-acyl ketimines, derived from 3-hydroxyisoindolinones has been demonstrated in this communication. A variety of isoindolinone-based α-amino diazo esters bearing a quaternary stereogenic center were afforded in high yields (up to 99%) with excellent enantioselectivities (up to 99% ee). Furthermore, the synthetic utility of the products has been depicted by the hydrogenation of the diazo moiety of adducts.

  12. Diastereoselective Ugi reaction of chiral 1,3-aminoalcohols derived from an organocatalytic Mannich reaction.

    Science.gov (United States)

    Caputo, Samantha; Basso, Andrea; Moni, Lisa; Riva, Renata; Rocca, Valeria; Banfi, Luca

    2016-01-01

    Enantiomerically pure β-aminoalcohols, produced through an organocatalytic Mannich reaction, were subjected to an Ugi multicomponent reaction under classical or Lewis acid-promoted conditions with diastereoselectivities ranging from moderate to good. This approach represents a step-economical path to enantiomerically pure, polyfunctionalized peptidomimetics endowed with three stereogenic centers, allowing the introduction of five diversity inputs.

  13. Direct catalytic enantioselective Mannich-type reaction of dichloroacetonitrile using bis(imidazoline)-Pd catalysts.

    Science.gov (United States)

    Kondo, Masaru; Sugimoto, Mami; Nakamura, Shuichi

    2016-11-15

    The catalytic enantioselective Mannich-type reaction of dichloroacetonitrile with imines has been developed. Good yields and enantioselectivity were observed for the reaction with various imines using chiral bis(imidazoline) catalysts. β-Aminonitriles or β-aminoamide were obtained from products without the loss of enantiopurity.

  14. RUTHENIUM-CATALYZED TANDEM OLEFIN MIGRATION-ALDOL AND MANNICH-TYPE REACTIONS IN IONIC LIQUID.

    Science.gov (United States)

    In the presence of a catalytic amount of RuCl2(PPh3)3, a cross-coupling of 3-buten-2-ol with aldehydes and imines was developed via a tandem olefin migration--aldol--Mannich reaction in bmim[PF6]. With In(OAc)3 as a co-catalyst, a-vinylbenzyl alcohol and aldehydes underwent sim...

  15. Chiral ammonium betaine-catalyzed asymmetric Mannich-type reaction of oxindoles.

    Science.gov (United States)

    Torii, Masahiro; Kato, Kohsuke; Uraguchi, Daisuke; Ooi, Takashi

    2016-01-01

    A highly diastereo- and enantioselective Mannich-type reaction of 3-aryloxindoles with N -Boc aldimines was achieved under the catalysis of axially chiral ammonium betaines. This catalytic method provides a new tool for the construction of consecutive quaternary and tertiary stereogenic carbon centers on biologically intriguing molecular frameworks with high fidelity.

  16. Mannich reaction of trifluoroacetaldehyde hydrazones: a useful entry to trifluoromethyl substituted heterocycles.

    Science.gov (United States)

    Jia, Shuanglong; El Kaim, Laurent

    2018-02-28

    NH-aryl hydrazones derived from trifluoroacetaldehyde hemiacetal may be involved in efficient Mannich type reactions with formaldehydes and aromatic aldehydes. The resulting hydrazones are useful building blocks for the preparation of trifluoromethyl substituted heterocycles as shown by a straightforward preparation of 1,2-diazine derivatives under heating with β-ketoesters.

  17. Diastereoselective Ugi reaction of chiral 1,3-aminoalcohols derived from an organocatalytic Mannich reaction

    OpenAIRE

    Caputo, Samantha; Basso, Andrea; Moni, Lisa; Riva, Renata; Rocca, Valeria; Banfi, Luca

    2016-01-01

    Summary Enantiomerically pure ?-aminoalcohols, produced through an organocatalytic Mannich reaction, were subjected to an Ugi multicomponent reaction under classical or Lewis acid-promoted conditions with diastereoselectivities ranging from moderate to good. This approach represents a step-economical path to enantiomerically pure, polyfunctionalized peptidomimetics endowed with three stereogenic centers, allowing the introduction of five diversity inputs.

  18. An Alumino-Mannich Reaction of Organoaluminum Reagents, Silylated Amines, and Aldehydes.

    Science.gov (United States)

    Tarasewicz, Anika; Ensan, Deeba; Batey, Robert A

    2018-03-08

    A multi-component coupling using organoaluminum reagents, silylated amines, and aldehydes results in the formation of tertiary amines. Both alkenyl- and alkylaluminum reagents undergo reaction with iminium ion substrates for which the corresponding Petasis borono-Mannich reactions are unsuccessful. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Diastereoselective Ugi reaction of chiral 1,3-aminoalcohols derived from an organocatalytic Mannich reaction

    Directory of Open Access Journals (Sweden)

    Samantha Caputo

    2016-01-01

    Full Text Available Enantiomerically pure β-aminoalcohols, produced through an organocatalytic Mannich reaction, were subjected to an Ugi multicomponent reaction under classical or Lewis acid-promoted conditions with diastereoselectivities ranging from moderate to good. This approach represents a step-economical path to enantiomerically pure, polyfunctionalized peptidomimetics endowed with three stereogenic centers, allowing the introduction of five diversity inputs.

  20. Dehydrative Mannich-Type Reaction for the Synthesis of Azepinobisindole Alkaloid Iheyamine A.

    Science.gov (United States)

    Abe, Takumi; Yamada, Koji

    2018-03-02

    A concise synthesis of the azepinobisindole alkaloid iheyamine A from an indole-2,3-epoxide equivalent has been achieved. This method features a formal C3 electrophilic reaction of an indole-2,3-epoxide equivalent with tryptamine to form a 3-aminoindoline and a novel In-catalyzed dehydrative Mannich-type reaction of the hemiaminal to give the azepinobisindole core.

  1. Highly Enantioselective Three-Component Direct Mannich Reactions of Unfunctionalized Ketones Catalyzed by Bifunctional Organocatalysts

    Science.gov (United States)

    Guo, Qunsheng; Zhao, John Cong-Gui

    2013-01-01

    A highly stereoselective three-component direct Mannich reaction between aromatic aldehydes, p-toluenesulfonamide, and unfunctionalized ketones was achieved through an enolate mechanism for the first time with a bifunctional quinidine thiourea catalyst. The corresponding N-tosylated β-aminoketones were obtained in high yields and excellent diastereo- and enantioselectivities (up to >99:1 dr and >99% ee). PMID:23343472

  2. A Sustainable Protocol for the Aqueous Multicomponent Petasis Borono-Mannich Reaction

    Science.gov (United States)

    Candeias, Nuno R.; Paterna, Roberta; Cal, Pedro M. S. D.; Gois, Pedro M. P.

    2012-01-01

    A protocol for the preparation of Petasis borono-Mannich products suitable for advanced organic chemistry experiments, using water as a reaction medium, was developed. The experiment is carried out in less than 4 h (with a 30 min pre-session on the day before) using commercially available starting materials in the preparation of phenylglycine and…

  3. ALDOL- AND MANNICH-TYPE REACTIONS VIA IN SITU OLEFIN MIGRATION IN IONIC LIQUID

    Science.gov (United States)

    An aldol-type and a Mannich-type reaction via the cross-coupling of aldehydes and imines with allylic alcohols catalyzed by RuCl2(PPh3)3 was developed with ionic liquid as the solvent. The solvent/catalyst system could be reused for at least five times with no loss of reactiv...

  4. Chiral ammonium betaine-catalyzed asymmetric Mannich-type reaction of oxindoles

    Directory of Open Access Journals (Sweden)

    Masahiro Torii

    2016-09-01

    Full Text Available A highly diastereo- and enantioselective Mannich-type reaction of 3-aryloxindoles with N-Boc aldimines was achieved under the catalysis of axially chiral ammonium betaines. This catalytic method provides a new tool for the construction of consecutive quaternary and tertiary stereogenic carbon centers on biologically intriguing molecular frameworks with high fidelity.

  5. An enantioselective Brønsted acid catalyzed enamine Mannich reaction.

    Science.gov (United States)

    Tillman, A Louise; Dixon, Darren J

    2007-02-21

    An enantioselective Brønsted acid catalyzed Mannich reaction between acetophenone derived enamines and N-Boc imines has been developed. Simple diol (S)-H(8)-BINOL has been identified as the optimal catalyst, to afford versatile beta-amino aryl ketones in good yield and enantiomeric excess.

  6. A new Mannich base and its transition metal (II) complexes ...

    Indian Academy of Sciences (India)

    The monomeric and non-electrolytic nature of the complexes is evidenced by their magnetic susceptibility and low conductance data. The electrochemical property of the ligand and its complexes in acetonitrile solution was studied by cyclic voltammetry. The X-band ESR spectra of the Cu(II) complex in DMSO at 300 and 77 ...

  7. Diesel fuel containing polyalkylene amine and Mannich base

    Energy Technology Data Exchange (ETDEWEB)

    Harle, O.L.

    1979-09-04

    Disclosed is a fuel additive and fuel composition. The additive comprises a mixture of a polyalkylene amine and the reaction product of an alkylphenol, an aldehyde and an amine. The additive provides surprising stability in preventing thermal degradation of fuels, particularly fuels for compression ignition engines.

  8. A new Mannich base and its transition metal (II) complexes ...

    Indian Academy of Sciences (India)

    Unknown

    Pelczar M J, Chan E C S and Krieg N R 1998 Micro- biology 5th edn (New York). 9. Lever A B P and Mantovani E 1971 Inorg. Chem. 10. 817. 10. Lever A B P 1968 Inorganic electronic spectroscopy. 2nd edn (New York: Elseiver). 11. Maki G 1958 J. Chem. Phys. 28 651. 12. Biradar N S and Havinale B R 1976 Inorg. Chim.

  9. Yttrium (III chloride catalyzed Mannich reaction: An efficient procedure for the synthesis of β-amino carbonyl compounds

    Directory of Open Access Journals (Sweden)

    Venkateswarlu Yekkirala

    2014-12-01

    Full Text Available Yttrium (III chloride catalyzed Mannich reaction of aldehydes with ketones and amines in acetonitrile at reflux temperature to give various β-amino carbonyl compounds in very good yields.

  10. Stereoselective, nitro-Mannich/lactamisation cascades for the direct synthesis of heavily decorated 5-nitropiperidin-2-ones and related heterocycles

    Directory of Open Access Journals (Sweden)

    Pavol Jakubec

    2012-04-01

    Full Text Available A versatile nitro-Mannich/lactamisation cascade for the direct stereoselective synthesis of heavily decorated 5-nitropiperidin-2-ones and related heterocycles has been developed. A highly enantioenriched substituted 5-nitropiperidin-2-one was synthesised in a four component one-pot reaction combining an enantioselective organocatalytic Michael addition with the diastereoselective nitro-Mannich/lactamisation cascade. Protodenitration and chemoselective reductive manipulation of the heterocycles was used to install contiguous and fully substituted stereocentres in the synthesis of substituted piperidines.

  11. Stereoselective, nitro-Mannich/lactamisation cascades for the direct synthesis of heavily decorated 5-nitropiperidin-2-ones and related heterocycles

    Science.gov (United States)

    Jakubec, Pavol; Cockfield, Dane M; Helliwell, Madeleine; Raftery, James

    2012-01-01

    Summary A versatile nitro-Mannich/lactamisation cascade for the direct stereoselective synthesis of heavily decorated 5-nitropiperidin-2-ones and related heterocycles has been developed. A highly enantioenriched substituted 5-nitropiperidin-2-one was synthesised in a four component one-pot reaction combining an enantioselective organocatalytic Michael addition with the diastereoselective nitro-Mannich/lactamisation cascade. Protodenitration and chemoselective reductive manipulation of the heterocycles was used to install contiguous and fully substituted stereocentres in the synthesis of substituted piperidines. PMID:22563355

  12. Stereoselective, nitro-Mannich/lactamisation cascades for the direct synthesis of heavily decorated 5-nitropiperidin-2-ones and related heterocycles

    OpenAIRE

    Pavol Jakubec; Dane M. Cockfield; Madeleine Helliwell; James Raftery; Darren J. Dixon

    2012-01-01

    Summary A versatile nitro-Mannich/lactamisation cascade for the direct stereoselective synthesis of heavily decorated 5-nitropiperidin-2-ones and related heterocycles has been developed. A highly enantioenriched substituted 5-nitropiperidin-2-one was synthesised in a four component one-pot reaction combining an enantioselective organocatalytic Michael addition with the diastereoselective nitro-Mannich/lactamisation cascade. Protodenitration and chemoselective reductive manipulation of the het...

  13. Stereoselective, nitro-Mannich/lactamisation cascades for the direct synthesis of heavily decorated 5-nitropiperidin-2-ones and related heterocycles.

    Science.gov (United States)

    Jakubec, Pavol; Cockfield, Dane M; Helliwell, Madeleine; Raftery, James; Dixon, Darren J

    2012-01-01

    A versatile nitro-Mannich/lactamisation cascade for the direct stereoselective synthesis of heavily decorated 5-nitropiperidin-2-ones and related heterocycles has been developed. A highly enantioenriched substituted 5-nitropiperidin-2-one was synthesised in a four component one-pot reaction combining an enantioselective organocatalytic Michael addition with the diastereoselective nitro-Mannich/lactamisation cascade. Protodenitration and chemoselective reductive manipulation of the heterocycles was used to install contiguous and fully substituted stereocentres in the synthesis of substituted piperidines.

  14. Cyclic aldimines as superior electrophiles for Cu-catalyzed decarboxylative Mannich reaction of β-ketoacids with a broad scope and high enantioselectivity.

    Science.gov (United States)

    Zhang, Heng-Xia; Nie, Jing; Cai, Hua; Ma, Jun-An

    2014-05-02

    A novel Cu-catalyzed enantioselective decarboxylative Mannich reaction of cyclic aldimines with β-ketoacids is described. The cyclic structure of these aldimines, in which the C═N bond is constrained in the Z geometry, appears to be important, allowing Mannich condensation to proceed in high yields with excellent enantioselectivities. A chiral chroman-4-amine was synthesized from the decarboxylative Mannich product in several steps without loss of enantioselectivity.

  15. Mannich reaction as a key strategy for the synthesis of benzoazacrown ethers and benzocryptands

    Energy Technology Data Exchange (ETDEWEB)

    Pastushok, V.N.; Bradshaw, J.S.; Izatt, R.M. [Brigham Young Univ., Provo, UT (United States); Bordunov, A.V. [IBC Advanced Technologies, Inc., American Fork, UT (United States)

    1996-10-04

    A convenient method for the synthesis of mono- and polycyclic azacrown macrocycles containing aromatic fragments using the Mannich condensation of phenols and secondary diamines has been studied. This new approach allowed the synthesis of bisphenols connected by oligoazaoxaalkane units in good yields without the need to protect the phenolic OH groups. These bisphenols (13-16) were alkylated with ditosylates of polyethylene glycols to give benzoazacrown ethers 25-30. Intermediate bisphenols 13-15 were also treated with three bis(methoxymethyl)-substituted diamines to form benzoazacrowns 10-12 containing internal phenolic functions. Phenol-containing mono (11) and bicyclic (3, n = 1) compounds, which were synthesized via the Mannich aminomethylation process, were used as building blocks for construction of bi- (32) and tricyclic (33) ligands. 11 refs.

  16. Study on the Synthesis and Corrosion Inhibition Performance of Mannich-Modified Imidazoline

    Directory of Open Access Journals (Sweden)

    Xiangjun Kong

    2016-07-01

    Full Text Available A novel Mannich-modified imidazoline (MMI as cationic emulsifier was synthesised for corrosion harm reduction, through three steps — acylation, cyclization, and Mannich reaction. The surface activity was characterized by determination of surface tensions and critical micelle concentration (CMC. The corrosion inhibition performance of five types of steels in the simulated corrosion solution in the presence of the MMI was investigated by static weight loss tests. The results showed that the MMI had good surface activities, with CMC of 19.8 μg g−1 and surface tension of 36.4 mN m−1. The corrosion test results indicated that the corrosion rates of different materials were decreased significantly, and degrees of corrosion inhibition were always higher than 80.0 %. The main inhibition mechanism was most likely due to the adsorption of the corrosion inhibitor on the steel surface, leading to the prevention of corrosion medium from the metal surface.

  17. Asymmetric synthesis of (-)-sedacryptine through a diastereoselective Mannich reaction of N,O-acetals with ketones.

    Science.gov (United States)

    Liu, Yi-Wen; Ma, Rui-Jun; Yan, Jia-Hang; Zhou, Zhu; Wei, Bang-Guo

    2018-01-31

    An efficient diastereoselective approach to access the 3-hydroxy-2,6-disubstituted piperidine scaffold 1 has been developed through the Mannich process involving N,O-acetal (2S,3R)-6 and ketones in excellent yield with high diastereoselectivity (dr > 99 : 1). In addition, the utility of this convenient one-pot process is demonstrated by the asymmetric synthesis of (-)-sedacryptine 3.

  18. Prolinate Salt as a Catalyst in the syn-Selective, Asymmetric Mannich Reaction of Alkynyl Imine.

    Science.gov (United States)

    Hayashi, Yujiro; Yamazaki, Tatsuya; Kawauchi, Genki; Sato, Itaru

    2018-04-04

    Prolinate salt is an efficient catalyst in the Mannich reaction of alkynyl imine and aldehyde, to afford synthetically useful chiral propargyl amine derivatives with excellent syn-selectivity and nearly perfect control of the absolute configuration. The counterion of the prolinate salt does not affect the enantioselectivity. This is a rare example, in which proline alkali metals, alkaline-earth metals, or ammonium salt show higher reactivity and better stereoselectivity than the parent proline.

  19. Visible light catalyzed Mannich reaction between tert-amines and silyl diazoenolates.

    Science.gov (United States)

    Pramanik, Mukund M D; Nagode, Savita B; Kant, Ruchir; Rastogi, Namrata

    2017-09-13

    The present work documents the α-C-H functionalization of tertiary amines via the visible light catalyzed Mannich reaction with silyl diazoenolates. The reaction takes place at room temperature with an organic dye, Rose Bengal, as a photocatalyst and oxygen as the oxidant. The resulting multifunctional products bearing an α-diazo-β-keto group undergo Rh-carbenoid mediated cyclization, affording stable ammonium ylides in high yields.

  20. Direct Catalytic Asymmetric Mannich-Type Reaction of α-N3 Amide.

    Science.gov (United States)

    Sun, Zhongdong; Weidner, Karin; Kumagai, Naoya; Shibasaki, Masakatsu

    2015-12-01

    An α-N3 7-azaindoline amide serves as a latent enolate to directly engage in an asymmetric Mannich-type reaction with N-thiophosphinoyl imines by the action of a cooperative catalyst. The thus-obtained highly enantioenriched anti-adduct was transformed into β-amino-α-azido acid in high yield by simple acidic treatment. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Synthesis of Indolines by a Zn-Mediated Mannich Reaction/Pd-Catalyzed Amination Sequence.

    Science.gov (United States)

    Presset, Marc; Pignon, Antoine; Paul, Jérôme; Le Gall, Erwan; Léonel, Eric; Martens, Thierry

    2017-03-17

    1,2-Disubstituted indolines have been prepared in fair to good yields by a Zn-mediated organometallic Mannich reaction, followed by an intramolecular Pd-catalyzed aromatic amination. The reactions are easy to set up and compatible with a large variety of simple or commercially available reagents. The method was further extended to the preparation of a 1,2,3-trisubstituted indoline.

  2. Organocatalytic asymmetric mannich-type reactions: an easy approach to optically active amine derivatives

    OpenAIRE

    Fini, Francesco

    2008-01-01

    The topics I came across during the period I spent as a Ph.D. student are mainly two. The first concerns new organocatalytic protocols for Mannich-type reactions mediated by Cinchona alkaloids derivatives (Scheme I, left); the second topic, instead, regards the study of a new approach towards the enantioselective total synthesis of Aspirochlorine, a potent gliotoxin that recent studies indicate as a highly selective and active agent against fungi (Scheme I, right). At the begin...

  3. Amination of biorefinery technical lignins using Mannich reaction synergy with subcritical ethanol depolymerization.

    Science.gov (United States)

    Wang, Bing; Chen, Tian-Ying; Wang, Han-Min; Li, Han-Yin; Liu, Chuan-Fu; Wen, Jia-Long

    2018-02-01

    The alcoholic depolymerization and Mannich reaction were conducted to improve the chemical activity of biorefinery technical lignins and introduce amino groups into lignins, respectively. To understand the chemical structural transformations and examine the reaction mechanism, GPC and solution-state NMR techniques were performed. Element analysis was also used to quantify the amount of amine groups. The NMR characterization the depolymerized lignins indicated of the depolymerization, demethoxylation, and bond cleavage of linkages occurred during the depolymerization process. Results showed that the depolymerization temperature instead of the addition of capping reagents was the main factor for improving the reactivity of lignin under the given conditions. The Mannich reaction was very selective, primarily occurred at H 3,5 and G 5 positions, and the H units present a higher chemical reactivity. It is believed that the understanding of the fundamental chemistry of lignin during depolymerization and Mannich reaction process will contribute to the extension of high value-added applications of biorefinery lignin. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. In situ generation of N-Boc-protected alkenyl imines: controlling the E/Z geometry of alkenyl moieties in the Mukaiyama-Mannich reaction.

    Science.gov (United States)

    Bai, Jian-Fei; Sasagawa, Hajime; Yurino, Taiga; Kano, Taichi; Maruoka, Keiji

    2017-07-18

    Readily available Boc-protected Z-alkenyl aminals could be used as Z-alkenyl and E-alkenyl imine precursors under acidic conditions. In the Mukaiyama-Mannich reaction of Z-alkenyl Boc-aminals, the E/Z geometry of the products was controlled by the catalyst used. The present method was also applied to asymmetric Mukaiyama-Mannich reactions.

  5. Gold (I)-Catalyzed Diastereo- and Enantioselective 1,3-Dipolar Cycloaddition and Mannich Reactions of Azlactones

    Science.gov (United States)

    Melhado, Asa D.; Amarante, Giovanni W.; Wang, Z. Jane; Luparia, Marco; Toste, F. Dean

    2011-01-01

    Azlactones participate in stereoselective reactions with electron-deficient alkenes and N-sulfonyl aldimines to give products of 1,3-dipolar cycloaddition and Mannich addition reactions respectively. Both of these reactions proceed with good to excellent diastereo- and enantioselectivity using a single class of gold-catalysts, namely C2-symmetric bis(phosphinegold(I) carboxylate)complexes. The development of the azlactone Mannich reaction to provide fully protected anti-α,β-diamino acid derivatives is described. 1,3-Dipolar cycloaddition reactions of several acyclic 1,2-disubstituted alkenes, and the chemistry of the resultant cycloadducts, are examined to probe the stereochemical course of this reaction. Reaction kinetics and tandem MS studies of both the cycloaddition and Mannich reactions are reported. These studies support a mechanism in which the gold complexes catalyze addition reactions through nucleophile activation rather than the more typical activation of the electrophilic reaction component. PMID:21341677

  6. A sensitive spectrofluorimetric method for the quantification of melamine residue in milk powder using the Mannich reaction in aqueous solutions.

    Science.gov (United States)

    Rima, Jamil; Assaker, Karine; El Omar, Fawaz; karim, Chawki bou

    2013-11-15

    The objective of this study was to develop a spectrofluorimetric method for the quantitative determination of melamine. The method was based on the complexation of melamine with a mixture of formaldehyde and chemicals including a ketone group, as described by the Mannich reaction. The complex was determined by spectrofluorimetric measurement as it is characterized by specific spectroscopic properties that are related to the chromophore of the ketone compounds. 1,3-Diphenylpropane-1,3-dione (DPPD) was tested as a ketone compound. The fluorescence spectrum of the complex presented a maximum of absorption at 325 nm.A quenching of the fluorescence occurred when melamine was added into the solution. The kinetic of fluorescence quenching was followed to determine quantitatively the melamine concentration. An internal standard was added to quantify melamine. The method was tested to determine the level of melamine in contaminated milk powder. The recovery value was 97% and the limit of detection was 0.007 μg mL(-1.) © 2013 Elsevier B.V. All rights reserved.

  7. Highly Enantioselective Construction of Fluoroalkylated Quaternary Stereocenters via Organocatalytic Dehydrated Mannich Reaction of Unprotected Hemiaminals with Ketones.

    Science.gov (United States)

    Zhang, Sheng; Li, Lijun; Hu, Yanbin; Li, Yanan; Yang, Yu; Zha, Zhenggen; Wang, Zhiyong

    2015-10-16

    A general organocatalytic asymmetric dehydrated Mannich reaction of fluoroalkyl hemiaminals with ketones is reported. In this Mannich reaction, previously less explored aryl ketones showed great reactivity. By virtue of this efficient method, a wide range of biologically active β-amino ketones were directly obtained. More importantly, two different intermediates involved in the reaction were detected and identified by (19)F NMR and HRMS analysis. Furthermore, the synthetic utility of the products was demonstrated by the synthesis of the biologically active fluoroalkyl β-amino alcohols.

  8. Stereoselective ZrCl4-Catalyzed Mannich-type Reaction of β-Keto Esters with Chiral Trifluoromethyl Aldimines.

    Science.gov (United States)

    Parise, Luca; Pellacani, Lucio; Sciubba, Fabio; Trulli, Laura; Fioravanti, Stefania

    2015-08-21

    A method for the synthesis of fluorinated β'-amino β-dicarbonyl compounds using a Zr-catalyzed Mannich-type reaction has been developed, starting from N-protected trifluoromethyl aldimines and cyclic or acyclic β-keto esters bearing different ester residues. The in situ generated metallic complex reacted with optically pure trifluoromethyl aldimine derived from (R)-α-methylbenzylamine, giving a highly diastereoselective asymmetric Mannich-type addition with formation of a chiral quaternary center. The absolute configuration at the new chiral centers was assigned through two-dimensional nuclear Overhauser effect spectroscopic analysis coupled with computational studies.

  9. Development of a syn-Selective Mannich Reaction of Aldehydes with Propargylic Imines by Dual Catalysis: Asymmetric Synthesis of Functionalized Propargylic Amines.

    Science.gov (United States)

    Lapuerta, Irati; Vera, Silvia; Oiarbide, Mikel; Palomo, Claudio

    2016-05-17

    Direct coupling of enolizable aldehydes with C-alkynyl imines is realized affording the corresponding propargylic Mannich adducts of syn configuration, thus complementing previous methods that gave access to the anti-isomers. The combination of proline and a urea Brønsted base cocatalyst is key for the reactions to proceed under very mild conditions (3-10 mol % catalyst loading, dichloromethane as solvent, -20 °C, 1.2 molar equivalents of aldehyde) and with virtually total stereocontrol (syn/anti ratio up to 99:1; ee up to 99 %). Some possibilities of further chemical elaboration of adducts are also briefly illustrated. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Group-Assisted Purification Chemistry for Asymmetric Mannich-type Reaction of Chiral N-Phosphonyl Imines with Azlactones Leading to Syntheses of α-Quaternary α,β-Diamino Acid Derivatives †.

    Science.gov (United States)

    Zhang, Haowei; Yang, Zhen; Zhao, Brian Nlong; Li, Guigen

    2018-01-19

    An asymmetric Mannich-type reaction between chiral N-phosphonyl imines and azlactones [oxazol-5(4H)-ones] has been established under convenient conditions at room temperature. The reaction was performed without using any bases, additives, or catalysts to achieve up to excellent chemical yields and diastereoselectivity for 32 examples. The α-quaternary syn-α,β-diamino acid products were purified simply by washing the crude mixtures with cosolvents, following the group-assisted purification chemistry/technology, without involving traditional chromatography or recrystallization methods. The auxiliary can be readily removed and recycled for reuse. The absolute configuration was unambiguously assigned by X-ray structural analysis.

  11. Design and synthesis of a novel class of sugar-peptide hybrids: C-linked glyco beta-amino acids through a stereoselective "acetate" Mannich reaction as the key strategic element.

    Science.gov (United States)

    Palomo, Claudio; Oiarbide, Mikel; Landa, Aitor; González-Rego, M Concepción; García, Jesús M; González, Alberto; Odriozola, José M; Martín-Pastor, Manuel; Linden, Anthony

    2002-07-24

    A new type of sugar-amino acid hybrid, which is comprised of a sugar unit (gluco-, galacto-, or mannopyranose) linked through a C-glycosidic linkage to the beta-position of an alpha-unsubstituted beta-amino acid unit, is presented. It is hypothesized that these new compounds, or the oligomeric peptides derived therefrom, might possess the structural features of beta-amino acid oligomers and the chemical and enzymatic resistance of C-glycosides to hydrolysis. The synthetic strategy is based on a new Mannich-type reaction between a chiral acetate enolate equivalent and alpha-amido sulfones derived from the corresponding sugar-C-glycoside aldehydes. While the sugar-C-glycoside aldehyde partner is prepared from well-established transformations on known sugar precursors, the lithium enolate derived from (1R)-endo-2-acetylisoborneol 3 is employed as the key element. This Mannich approach proceeds with essentially perfect diasteromeric control leading to the new beta-amino carbonyl adducts in good yields. Further, cleavage of the camphor auxiliary is smoothly performed by oxidative treatment with ammonium cerium nitrate (CAN). Complementarily, direct peptide-type coupling of the beta-amino carbonyl Mannich adducts with an alpha- or beta-amino acid residue and subsequent CAN-promoted detachment of the auxiliary yields dipeptide fragments bearing a sugar-containing aliphatic side chain and is a process that can be iterated. A preliminary conformational study based on the combination of experimental NMR data and molecular mechanics and molecular dynamics (MD) of one particular adduct is also provided.

  12. Direct catalytic enantio- and diastereoselective Mannich reaction of isocyanoacetates and ketimines.

    Science.gov (United States)

    Ortín, Irene; Dixon, Darren J

    2014-03-24

    A catalytic asymmetric synthesis of imidazolines with a fully substituted β-carbon atom by a Mannich-type addition/cyclization reaction of isocyanoacetate pronucleophiles and N-diphenylphosphinoyl ketimines has been developed. When a combination of a cinchona-derived aminophosphine precatalyst and silver oxide was employed as a binary catalyst system, good reactivity, high diastereoselectivities (up to 99:1 d.r.), and excellent enantioselectivities (up to 99% ee) were obtained for a range of substrates. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Diastereoselective synthesis of 1,3,5-trisubstituted 4-nitropyrrolidin-2-ones via a nitro-Mannich/lactamization cascade.

    Science.gov (United States)

    Pelletier, Sophie M-C; Ray, Peter C; Dixon, Darren J

    2011-12-16

    A versatile one-pot nitro-Mannich/lactamization cascade for the direct synthesis of 1,3,5-trisubstituted 4-nitropyrrolidin-2-ones has been developed. The reaction is easy to perform and broad in scope, and high levels of diastereoselectivity can be achieved.

  14. Synthetic modification of hydroxychavicol by Mannich reaction and alkyne-azide cycloaddition derivatives depicting cytotoxic potential.

    Science.gov (United States)

    Kumar, Sunil; Pathania, Anoop S; Satti, Naresh K; Dutt, Parbhu; Sharma, Neha; Mallik, Fayaz A; Ali, Asif

    2015-03-06

    Here we report the design, synthesis and lead optimization of hydroxychavicol (1) a high yielding metabolite ubiquitously present in the Piper betel leaves with the significant cytotoxic activity. This is the first report to describe the synthetic strategies of two distinct series of hydroxychavicol by Mannich reaction (2-10) and alkyne-azide cycloaddition (11-20). Furthermore, all the synthesized derivatives along with parent compound were evaluated for their in-vitro cytotoxic and antiproliferative potential in several distinct cancers cell lines. Among all, the Mannich reaction derived molecules 6, 8 and 10 displayed more potent cytotoxic activities with IC50 value in a range from 3 to 9 μM, which were 7-10 fold more potent than 1 against five human cancer cell lines viz. HL-60, Mia PaCa-2, MCF-7, HEP G2 and SK-N-SH. Our results describe an efficient synthetic approach used to evaluate the structure activity relationship of 1 and its derivative in search of potential new anticancer agents. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  15. Catalytic Asymmetric Decarboxylative Mannich Reaction of Malonic Acid Half Esters with Cyclic Aldimines: Access to Chiral β-Amino Esters and Chroman-4-amines.

    Science.gov (United States)

    Jia, Chun-Man; Zhang, Heng-Xia; Nie, Jing; Ma, Jun-An

    2016-09-16

    An enantioselective decarboxylative Mannich reaction of malonic acid half esters (MAHEs) with cyclic aldimines has been accomplished by employing the copper(I)/(R,R)-Ph-Box complex as chiral catalyst. The desired β-amino esters were obtained in good to high yields with excellent enantioselectivities. Furthermore, one of the corresponding Mannich products could be readily transformed into chiral chroman-4-amines without loss of enantioselectivity, which is a key intermediate of the human Bradykinin B1 receptor antagonist.

  16. Synthesis of some derivatives of compounds β-aminoketonic through Mannich reaction by usingbiocatalysts

    Directory of Open Access Journals (Sweden)

    Ana Claudia S. Lima

    2012-06-01

    Full Text Available The Mannich reaction is one of the most widely used reactions in organic chemistry, and also one of the first examples of a multicomponent reaction already described on the literature. This reaction results in β-aminocarbonylated compounds which allow the generation of several structures that can be used in the synthesis of both biologically active molecules, and natural products, however, just a few synthetic routes resulting in the formation of β-aminocarbonylated compound are known. In this sense, new methodologies have been developed by involving new catalysts or chiral auxiliaries in the synthesis of β-aminocarbonylated compounds with biological activity. One of these methodologies is the biocatalysis, which is a technique that uses biological catalysts, like enzymes or micro-organisms to convert a substrate in a limited number of enzymatic steps. The use of micro-organisms, plants or isolated enzymes as chiral catalysts has proportioned a significant advance in the synthetic chemistry, because it is known that the biocatalysts have selective catalytic sites that afford the formation of enantiomerically pure products and which is extremely important, because it is known that differences of the chirality may have tragic or spectacular effects in humans. Concerning to the environmental issue, the biocatalysis is placed within the context of a new philosophy called Green Chemistry. However, in the State of Mato Grosso do Sul the researches involving this issue of biocatalysis are still incipient once that by the year of 2010 there was only one research group focused on this themeregistered in the Lattes Platform in the State. Because of the need of support to the researches focused on this issue in the State of Mato Grosso do Sul and to evaluate thebiocatalytic potential of different lineage of microorganisms and enzymes in the synthesis of compounds β-aminoketonic through Mannich reaction it was proposed the use of someenzymes such as

  17. L-proline-catalyzed enantioselective one-pot cross-Mannich reaction of aldehydes.

    Science.gov (United States)

    Hayashi, Yujiro; Urushima, Tatsuya; Tsuboi, Wataru; Shoji, Mitsuru

    2007-01-01

    This protocol describes a procedure for the synthesis of syn-beta-amino alpha-substituted aldehydes, versatile intermediates in synthetic organic chemistry, via asymmetric, direct, one-pot, three-component, cross-Mannich reaction of two different aldehydes. The reaction consists of two steps; one is the formation of imine by the reaction of aldehyde and p-anisidine in the presence of Pro, and the second step is the enantioselective addition reaction of enamine generated from the other aldehyde and Pro with the imine generated in the first step. As the aldehyde easily racemizes, gamma-amino alcohol was isolated and characterized after reduction. The yield and diastereo- and enantioselectivities are generally excellent. It will take approximately 26 h to complete the protocol: 0.5 h to set up the reaction, 20.5 h for the reaction and 5 h for the isolation and purification.

  18. Accurate Reaction Enthalpies and Sources of Error in DFT Thermochemistry for Aldol, Mannich, and α-Aminoxylation Reactions

    Science.gov (United States)

    Wheeler, Steven E.; Moran, Antonio; Pieniazek, Susan N.; Houk, K. N.

    2009-08-01

    Enthalpies for bond-forming reactions that are subject to organocatalysis have been predicted using the high-accuracy CBS-QB3 model chemistry and six DFT functionals. Reaction enthalpies were decomposed into contributions from changes in bonding and other intramolecular effects via the hierarchy of homodesmotic reactions. The order of the reaction exothermicities (aldol Mannich ≈ α-aminoxylation) arises primarily from changes in formal bond types mediated by contributions from secondary intramolecular interactions. In each of these reaction types, methyl substitution at the β- and γ-positions stabilizes the products relative to the unsubstituted case. The performance of six DFT functionals (B3LYP, B3PW91, B1B95, MPW1PW91, PBE1PBE, and M06-2X), MP2, and SCS-MP2 has been assessed for the prediction of these reaction enthalpies. Even though the PBE1PBE and M06-2X functionals perform well for the aldol and Mannich reactions, errors roughly double when these functionals are applied to the α-aminoxylation reactions. B3PW91 and B1B95, which offer modest accuracy for the aldol and Mannich reactions, yield reliable predictions for the two α-aminoxylation reactions. The excellent performance of the M06-2X and PBE1PBE functionals for aldol and Mannich reactions stems from the cancellation of sizable errors arising from inadequate descriptions of the underlying bond transformations and intramolecular interactions. SCS-MP2/cc-pVTZ performs most consistently across these three classes of reactions, although the reaction exothermicities are systematically underestimated by 1-3 kcal mol-1. Conventional MP2, when paired with the cc-pVTZ basis set, performs somewhat better than SCS-MP2 for some of these reactions, particularly the α-aminoxylations. Finally, the merits of benchmarking DFT functionals for the set of simple chemically meaningful transformations underlying all bond-forming reactions are discussed.

  19. Dinuclear PhosphoiminoBINOL-Pd Container for Malononitrile: Catalytic Asymmetric Double Mannich Reaction for Chiral 1,3-Diamine Synthesis.

    Science.gov (United States)

    Arai, Takayoshi; Sato, Katsuya; Nakamura, Ayu; Makino, Hiroki; Masu, Hyuma

    2018-01-16

    A phosphoiminoBINOL ligand was designed to form a dinuclear metal complex that could hold a malononitrile molecule. The dinuclear bis(phosphoimino)binaphthoxy-Pd 2 (OAc) 2 complex catalyzed a double Mannich reaction of N-Boc-imines with malononitrile to give chiral 1,3-diamines with high enantioselectivity. The rational asymmetric catalyst, which smoothly introduces the first coupling product to the second coupling reaction while avoiding the reverse reaction, facilitates the over-reaction into a productive reaction process.

  20. Catalytic Asymmetric Mukaiyama-Mannich Reaction of Cyclic C-Acylimines with Difluoroenoxysilanes: Access to Difluoroalkylated Indolin-3-ones.

    Science.gov (United States)

    Li, Jin-Shan; Liu, Yong-Jie; Zhang, Guang-Wu; Ma, Jun-An

    2017-12-01

    A catalytic enantioselective Mukaiyama-Mannich reaction of cyclic C-acylimines with difluoroenoxysilanes is reported. (S)-TRIP enables the enantioselective synthesis of a series of novel difluoroalkylated indolin-3-ones bearing a quaternary stereocenter in up to 97% yield and 98% ee. The synthetic utility of this protocol is highlighted by efficient conversion of the products to the corresponding indolin-3-one derivatives without any erosion of the enantiopurity.

  1. Accurate reaction enthalpies and sources of error in DFT thermochemistry for aldol, Mannich, and alpha-aminoxylation reactions.

    Science.gov (United States)

    Wheeler, Steven E; Moran, Antonio; Pieniazek, Susan N; Houk, K N

    2009-09-24

    Enthalpies for bond-forming reactions that are subject to organocatalysis have been predicted using the high-accuracy CBS-QB3 model chemistry and six DFT functionals. Reaction enthalpies were decomposed into contributions from changes in bonding and other intramolecular effects via the hierarchy of homodesmotic reactions. The order of the reaction exothermicities (aldol Mannich approximately alpha-aminoxylation) arises primarily from changes in formal bond types mediated by contributions from secondary intramolecular interactions. In each of these reaction types, methyl substitution at the beta- and gamma-positions stabilizes the products relative to the unsubstituted case. The performance of six DFT functionals (B3LYP, B3PW91, B1B95, MPW1PW91, PBE1PBE, and M06-2X), MP2, and SCS-MP2 has been assessed for the prediction of these reaction enthalpies. Even though the PBE1PBE and M06-2X functionals perform well for the aldol and Mannich reactions, errors roughly double when these functionals are applied to the alpha-aminoxylation reactions. B3PW91 and B1B95, which offer modest accuracy for the aldol and Mannich reactions, yield reliable predictions for the two alpha-aminoxylation reactions. The excellent performance of the M06-2X and PBE1PBE functionals for aldol and Mannich reactions stems from the cancellation of sizable errors arising from inadequate descriptions of the underlying bond transformations and intramolecular interactions. SCS-MP2/cc-pVTZ performs most consistently across these three classes of reactions, although the reaction exothermicities are systematically underestimated by 1-3 kcal mol(-1). Conventional MP2, when paired with the cc-pVTZ basis set, performs somewhat better than SCS-MP2 for some of these reactions, particularly the alpha-aminoxylations. Finally, the merits of benchmarking DFT functionals for the set of simple chemically meaningful transformations underlying all bond-forming reactions are discussed.

  2. Synthesis of the reported structure of piperazirum using a nitro-Mannich reaction as the key stereochemical determining step

    Directory of Open Access Journals (Sweden)

    James C. Anderson

    2013-08-01

    Full Text Available Piperazirum, isolated from Arum palaestinum Boiss, was originally assigned as r-3,c-5-diisobutyl-c-6-isopropylpiperazin-2-one. The reported structure was synthesised diastereoselectively using a key nitro-Mannich reaction to set up the C5/C6 relative stereochemistry. The structure was unambiguously assigned by single crystal X-ray diffraction but the spectroscopic data did not match those reported for the natural product. The structure of the natural product must therefore be revised.

  3. The Mannich Reaction of Malonates with Simple Imines Catalyzed by Bifunctional Cinchona Alkaloids: Enantioselective Synthesis of β-Amino Acids

    Science.gov (United States)

    Song, Jun; Wang, Yi; Deng, Li

    2011-01-01

    We describe the first efficient, direct asymmetric Mannich reactions with malonates and N-Boc aryl and alkyl imines by cooperative hydrogen bonding catalysis with a cinchona alkaloid bearing a thiourea functionality. We have also extended the scope of this reaction to β-ketoesters. The synthetic value of this new reaction is demonstrated in the establishment of a convergent enantioselective route toward the biologically important β-amino acids under mild and air- and moisture-tolerant conditions. PMID:16669669

  4. Silica-supported boric acid with ionic liquid: a novel recyclable catalytic system for one-pot three-component Mannich reaction.

    Science.gov (United States)

    Kumar, Vishal; Sharma, Upendra; Verma, Praveen Kumar; Kumar, Neeraj; Singh, Bikram

    2011-01-01

    A rapid and efficient silica-supported boric acid/ionic liquid ([bmim][PF₆]), catalyzed, one-pot three-component Mannich reaction has been carried out to synthesize β-amino carbonyl compounds at room temperature. The reaction afforded desired products in excellent yields with moderate to good diastereoselectivity. The method provides a novel modification of three-component Mannich reaction in terms of mild reaction conditions, clean reaction profiles, low amount of catalyst, recyclability of catalyst and a simple workup procedure. The present report first time describes the preparation of H₃BO₃-SiO₃ catalyst and its use with [bmim][PF₆], to synthesize Mannich products. The catalyst can be reused at least seven times.

  5. 2-Chlorophenyl Zinc Bromide: A Convenient Nucleophile for the Mannich-Related Multicomponent Synthesis of Clopidogrel and Ticlopidine

    Directory of Open Access Journals (Sweden)

    Isabelle Aillaud

    2010-11-01

    Full Text Available A methodological study devoted to the Mannich-like multicomponent synthesis of the antiplatelet agent (±‑clopidogrel (7 and the ethyl ester analogue 6 is described. The process involves the formation of 2-chlorophenyl zinc bromide (2 and its subsequent reaction with an alkyl glyoxylate and 4,5,6,7-tetrahydrothieno[3,2-c]pyridine (3. We demonstrate that the organozinc reagent 2 also constitutes a very convenient nucleophile for the multicomponent synthesis of the benzylamine core of ticlopidine (9.

  6. One-pot cascade synthesis of azabicycles via the nitro-Mannich reaction and N-alkylation.

    Science.gov (United States)

    Disadee, Wannaporn; Ruchirawat, Somsak

    2018-01-31

    A one-pot, metal-free process for the synthesis of azabicycles is developed. The key transformations involved a cascade of double intramolecular cyclizations via the nitro-Mannich reaction and N-alkylation, providing various ring systems of azabicycles in yields up to 81% and an isomeric ratio of 62 : 1. This approach offers considerable advantages in terms of the handling of small molecules, the flexibility to introduce a functionalized side chain, and gives direct access to various azabicycles.

  7. Rh-Catalyzed reductive Mannich-type reaction and its application towards the synthesis of (±-ezetimibe

    Directory of Open Access Journals (Sweden)

    Motoyuki Isoda

    2016-07-01

    Full Text Available An effective synthesis for syn-β-lactams was achieved using a Rh-catalyzed reductive Mannich-type reaction. A rhodium–hydride complex (Rh–H derived from diethylzinc (Et2Zn and a Rh catalyst was used for the 1,4-reduction of an α,β-unsaturated ester to give a Reformatsky-type reagent, which in turn, reacted with an imine to give the syn-β-lactam. Additionally, the reaction was applied to the synthesis of (±-ezetimibe, a potent β-lactamic cholesterol absorption inhibitor.

  8. Rh-Catalyzed reductive Mannich-type reaction and its application towards the synthesis of (±)-ezetimibe.

    Science.gov (United States)

    Isoda, Motoyuki; Sato, Kazuyuki; Kunugi, Yurika; Tokonishi, Satsuki; Tarui, Atsushi; Omote, Masaaki; Minami, Hideki; Ando, Akira

    2016-01-01

    An effective synthesis for syn-β-lactams was achieved using a Rh-catalyzed reductive Mannich-type reaction. A rhodium-hydride complex (Rh-H) derived from diethylzinc (Et2Zn) and a Rh catalyst was used for the 1,4-reduction of an α,β-unsaturated ester to give a Reformatsky-type reagent, which in turn, reacted with an imine to give the syn-β-lactam. Additionally, the reaction was applied to the synthesis of (±)-ezetimibe, a potent β-lactamic cholesterol absorption inhibitor.

  9. A tandem Mannich addition–palladium catalyzed ring-closing route toward 4-substituted-3(2H-furanones

    Directory of Open Access Journals (Sweden)

    Jubi John

    2014-06-01

    Full Text Available A facile route towards highly functionalized 3(2H-furanones via a sequential Mannich addition–palladium catalyzed ring closing has been elaborated. The reaction of 4-chloroacetoacetate esters with imines derived from aliphatic and aromatic aldehydes under palladium catalysis afforded 4-substituted furanones in good to excellent yields. 4-Hydrazino-3(2H-furanones could also be synthesized from diazo esters in excellent yields by utilising the developed strategy. We could also efficiently transform the substituted furanones to aza-prostaglandin analogues.

  10. Enantio- and Diastereoselective Nitro-Mannich Reaction of α-Aryl Nitromethanes with Amidosulfones Catalyzed by Phase-Transfer Catalysts.

    Science.gov (United States)

    Lu, Ning; Li, Ruxu; Wei, Zhonglin; Cao, Jungang; Liang, Dapeng; Lin, Yingjie; Duan, Haifeng

    2017-05-05

    A high-yield, highly diastereo- and enantioselective nitro-Mannich reaction of α-aryl nitromethanes with amidosulfones catalyzed by a novel chiral phase-transfer catalyst, bearing multiple H-bonding donors, derived from quinine was developed. A variety of α-aryl nitromethanes and amidosulfones were investigated; and the corresponding products were obtained in excellent yields with excellent diastereo- and enantioselectivities (up to 99% yield, > 99:1 dr and >99% ee). As a demonstration of synthetic utility, the resulting β-nitroamines could be converted to corresponding meso-symmetric and optically pure unsymmetric anti-1,2-diarylethylenediamines.

  11. Asymmetric organocatalytic decarboxylative Mannich reaction using β-keto acids: A new protocol for the synthesis of chiral β-amino ketones

    Science.gov (United States)

    Jiang, Chunhui; Zhong, Fangrui

    2012-01-01

    Summary The first decarboxylative Mannich reaction employing β-keto acids, catalyzed by cinchonine-derived bifunctional thiourea catalyst has been described. The desired β-amino ketones were obtained in excellent yields and with moderate to good enantioselectivities. PMID:23019459

  12. A novel homobimetallic nickel complex for the asymmetric direct Mannich reaction of imines: a practical method on a multi-gram scale.

    Science.gov (United States)

    Zhang, Shixiong; Deng, Ping; Zhou, Jing; Liu, Mouxiong; Liang, Guojuan; Xiong, Yan; Zhou, Hui

    2017-11-30

    A novel dinuclear Ni complex has been developed for the direct Mannich reaction of malonates with N-tosyl aryl imines with a low catalyst loading (0.1-0.05 mol%) on a preparative scale (5-50 mmol). The structure of the active species was verified via control experiments, ESI-HRMS, and DFT calculations.

  13. Asymmetric organocatalytic decarboxylative Mannich reaction using β-keto acids: A new protocol for the synthesis of chiral β-amino ketones

    Directory of Open Access Journals (Sweden)

    Chunhui Jiang

    2012-08-01

    Full Text Available The first decarboxylative Mannich reaction employing β-keto acids, catalyzed by cinchonine-derived bifunctional thiourea catalyst has been described. The desired β-amino ketones were obtained in excellent yields and with moderate to good enantioselectivities.

  14. In situ generation of less accessible Boc-imines from aldehydes: construction of a quaternary carbon by the Mannich reaction or unprecedented aldol reaction.

    Science.gov (United States)

    Kano, Taichi; Homma, Chihiro; Maruoka, Keiji

    2017-05-31

    In situ generation of less accessible N-Boc-protected imines from aldehydes and their application to the direct three-component Mannich reaction with β-dicarbonyls were realized. The catalyst-free aldol reaction of ynals with β-dicarbonyls was also developed.

  15. Synthesis of Tetrahydropyridazines by a Metal-carbene Directed Highly Enantioselective Vinylogous N-H Insertion/Lewis Acid Catalyzed Diastereoselective Mannich Addition

    Science.gov (United States)

    Xu, Xinfang; Zavalij, Peter Y.

    2012-01-01

    A versatile reaction cascade triggered by Rh(II)-catalyzed diazo decomposition followed by a vinylogous N-H insertion/Lewis acid catalyzed Mannich addition that produces highly substituted 1,2,3,6-tetrahydropyridazines in up to 97% ee with high yield and diastereocontrol has been developed. PMID:22945294

  16. Synthesis of Tetrahydropyridazines by a Metal-carbene Directed Highly Enantioselective Vinylogous N-H Insertion/Lewis Acid Catalyzed Diastereoselective Mannich Addition

    OpenAIRE

    Xu, Xinfang; Zavalij, Peter Y.; Doyle, Michael P.

    2012-01-01

    A versatile reaction cascade triggered by Rh(II)-catalyzed diazo decomposition followed by a vinylogous N-H insertion/Lewis acid catalyzed Mannich addition that produces highly substituted 1,2,3,6-tetrahydropyridazines in up to 97% ee with high yield and diastereocontrol has been developed.

  17. Multiple reaction pathways operating in the mechanism of vinylogous Mannich-type reaction activated by a water molecule.

    Science.gov (United States)

    Uematsu, Ryohei; Maeda, Satoshi; Taketsugu, Tetsuya

    2014-01-01

    A systematic search for reaction pathways for the vinylogous Mannich-type reaction was performed by the artificial force induced reaction method. This reaction affords δ-amino-γ-butenolide in one pot by mixing 2-trimethylsiloxyfuran, imine, and water under solvent-free conditions. Surprisingly, the search identified as many as five working pathways. Among them, two concertedly produce anti and syn isomers of the product. Another two give an intermediate, which is a regioisomer of the main product. This intermediate can undergo a retro-Mannich reaction to give a pair of intermediates: an imine and 2-furanol. The remaining pathway directly generates this intermediate pair. The imine and 2-furanol easily react with each other to afford the product. Thus, all of these stepwise pathways finally converge to give the main product. The rate-determining step of all five (two concerted and three stepwise) pathways have a common mechanism: concerted Si-O bond formation through the nucleophilic attack of a water molecule on the silicon atom followed by proton transfer from the water molecule to the imine. Therefore, these five pathways have comparable barriers and compete with each other. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Choline-based biodegradable ionic liquid catalyst for Mannich-type ...

    Indian Academy of Sciences (India)

    aCollege of Chemical Engineering, Nanjing Tech University, Nanjing 210009, People's Republic of China. bSchool of Chemistry & Environmental Engineering, Yancheng Teachers University, Yancheng 224002,. People's Republic of China e-mail: fangdong106@sina.com. MS received 2 February 2016; revised 20 October ...

  19. Preparation and Characterization of Cyano Complexes of Oxotungsten(IV with Mannich Base Ligands

    Directory of Open Access Journals (Sweden)

    Mohita Sharma

    2010-01-01

    Full Text Available Oxocyanotungsten(IV complexes, (Ph3P2 NH2 [WO(CN3 L–L]. 3H2O and Cs[WO(CN3L–L].H2O (where L–L = morpholinobenzyl benzamide (MBB, piperidinobenzyl benzamide (PBB, piperidinobenzyl urea (PBU, piperidinobenzyl thiourea (PBTU, morpholinobenzyl urea (MBU and morpholinobenzyl thiourea (MBTU were synthesized. The complexes have been prepared by the reaction of K3Na [WO2(CN4].6H2O with morpholinobenzyl urea and related ligands in aqueous solution around pH of 7-8. These have been isolated as bis(triphenylphosphineiminium or cesium salts. The complexes have been characterized by elemental analysis, IR, 1H NMR, UV-Vis spectra, magnetic susceptibility, conductivity measurements and TGA/DTA studies.

  20. Versatile In Situ Generated N-Boc-Imines: Application to Phase-Transfer-Catalyzed Asymmetric Mannich-Type Reactions.

    Science.gov (United States)

    Kano, Taichi; Kobayashi, Ryohei; Maruoka, Keiji

    2015-07-13

    The efficient construction of nitrogen-containing organic compounds is a major challenge in chemical synthesis. Imines are one of the most important classes of electrophiles for this transformation. However, both the available imines and applicable nucleophiles for them are quite limited given the existing preparative methods. Described herein are imine precursors which generate reactive imines with a wide variety of substituents under mild basic conditions. This approach enables the construction of various nitrogen-containing molecules which cannot be accessed by the traditional approach. The utility of the novel imine precursor was demonstrated in the asymmetric Mannich-type reaction under phase-transfer conditions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Asymmetric Mannich reactions of imidazo[2,1-b]thiazole-derived nucleophiles with (S(S))-N-tert-butanesulfinyl (3,3,3)-trifluoroacetaldimine.

    Science.gov (United States)

    Mei, Haibo; Xie, Chen; Wu, Lingmin; Soloshonok, Vadim A; Han, Jianlin; Pan, Yi

    2013-12-14

    Asymmetric Mannich reactions of imidazo[2,1-b]thiazole-derived nucleophiles with (SS)-N-tert-butanesulfinyl (3,3,3)-trifluoroacetaldimine were found to proceed with reasonably good yields (55%-79%) and exceptionally high stereoselectivity (>99 : 1 dr). This method presents a general approach for the preparation of a new type of biologically relevant compounds containing pharmacophoric imidazo[2,1-b]thiazole and (trifluoro)ethylamine groups.

  2. Organocatalytic Asymmetric Mannich/Aza-Michael Cascade Reaction of δ-Formyl-α,β-unsaturated Ketones with Cyclic N-Sulfimines: Enantioselective Synthesis of Benzosulfamidate-Fused Pyrrolidines.

    Science.gov (United States)

    Kim, Hanna; Kim, Yerin; Kim, Sung-Gon

    2017-08-04

    A catalytic highly enantioselective Mannich/aza-Michael cascade reaction of δ-formyl-α,β-unsaturated ketones with cyclic N-sulfimines, promoted by diphenylprolinol TMS ether as an organocatalyst, has been developed for the synthesis of chiral benzosulfamidate-fused pyrrolidines, which generated in good yields and with high diastero- and enantioselectivities. Further chemical transformations have been performed with chiral benzosulfamidate-fused pyrrolidines.

  3. 2-methyl-3-butyn-2-ol as an acetylene precursor in the Mannich reaction. A new synthesis of suicide inactivators of monoamine oxidase

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, J.S.

    1977-07-22

    A two-step reaction process is reported for the synthesis of /sup 11/C, /sup 13/C, or /sup 14/C-labelled propargylamines in moderate yields. The propargylamines were prepared by a modified Mannich scheme without the use of acetylene. The reaction scheme involved the use of 2-methyl-3-butyn-2-ol followed by KOH-catalyzed elimination of acetone from the acetylenic carbinols. (BLM)

  4. An asymmetric Mannich reaction of α-diazocarbonyl compounds and N-sulfonyl cyclic ketimines catalyzed by complexes generated from chiral and achiral phosphines with gold(i).

    Science.gov (United States)

    Zhou, Minghui; Su, Qin; Addepalli, Yesu; He, Yun; Wang, Zhen

    2018-04-05

    An unprecedented Lewis acidic gold(i)-complex generated from chiral and achiral phosphines has been developed for the Mannich reaction of α-diazocarbonyl compounds and N-sulfonyl cyclic ketimines. A series of chiral β-amino-α-diazoesters bearing a quaternary stereocenter were obtained in high yields with good enantioselectivities. In addition, the products could be converted to promising bioactive spirosuccinimide. Furthermore, operando IR, NMR and control experiments were carried out to gain insight into the mechanism.

  5. Synthesis of tetrahydropyridazines by a metal-carbene-directed enantioselective vinylogous N-H insertion/Lewis acid-catalyzed diastereoselective Mannich addition.

    Science.gov (United States)

    Xu, Xinfang; Zavalij, Peter Y; Doyle, Michael P

    2012-09-24

    A versatile cascade of reactions, triggered by Rh(II)-catalyzed diazo decomposition followed by a vinylogous N-H insertion/Lewis acid catalyzed Mannich addition, that produces highly substituted 1,2,3,6-tetrahydropyridazines in up to 97 % ee with high yield and diastereocontrol has been developed. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Novel in vivo active anti-malarials based on a hydroxy-ethyl-amine scaffold.

    Science.gov (United States)

    Ciana, Claire-Lise; Siegrist, Romain; Aissaoui, Hamed; Marx, Léo; Racine, Sophie; Meyer, Solange; Binkert, Christoph; de Kanter, Ruben; Fischli, Christoph; Wittlin, Sergio; Boss, Christoph

    2013-02-01

    A novel series of anti-malarials, based on a hydroxy-ethyl-amine scaffold, initially identified as peptidomimetic protease inhibitors is described. Combination of the hydroxy-ethyl-amine anti-malarial phramacophore with the known Mannich base pharmacophore of amodiaquine (57) resulted in promising in vivo active novel derivatives. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. A facile one-pot Mannich reaction for the construction of fluorescent polymeric nanoparticles with aggregation-induced emission feature and their biological imaging.

    Science.gov (United States)

    Jiang, Ruming; Liu, Han; Liu, Meiying; Tian, Jianwen; Huang, Qiang; Huang, Hongye; Wen, Yuanqing; Cao, Qian-Yong; Zhang, Xiaoyong; Wei, Yen

    2017-12-01

    Multicomponent reactions (MCRs) have recently attracted great attention as one of the most important tools for the construction of various organic compounds in modern organic chemistry. In this work, we introduced an efficient one-pot strategy to successfully fabricate the fluorescent polymeric nanoparticles (FPNs) with aggregation-induced emission (AIE) characteristic via the conjugation of hyperbranched polyamino compound polyethyleneimine (PEI), AIE dye (named as PhE-OH) and paraformaldehyde (PF) through a Mannich reaction. The final amphiphilies (PEI-PF-PhE) can self-assemble into micelles in aqueous solution. We demonstrated PEI-PF-PhE FPNs showed high water dispersity, intense orange-yellow fluorescence, excellent photostability, low toxicity and high cell imaging performance. As compared with other construction strategies, the one-pot Mannich reaction possesses a number of advantages, such as simplicity, atom economy, high-efficiency and multifunctional potential. Combined with the remarkable properties of the AIE-active FPNs and the one-pot Mannich reaction, we could expect that the strategy developed in this work should be a useful tool for construction of various AIE-active functional materials for biomedical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Enantioselective conjugate addition nitro-Mannich reactions: solvent controlled synthesis of acyclic anti- and syn-β-nitroamines with three contiguous stereocenters.

    Science.gov (United States)

    Anderson, James C; Stepney, Gregory J; Mills, Matthew R; Horsfall, Lisa R; Blake, Alexander J; Lewis, William

    2011-04-01

    We report an enantioselective conjugate addition nitro-Mannich reaction protocol which combines dialkylzinc, aromatic nitro alkene and imine to form two C-C bonds and three contiguous stereocenters in one reaction vessel. Absolute stereochemistry was controlled from the initial 1,4-addition of dialkylzinc to aromatic nitroalkenes by known copper-chiral ligand catalysts. The choice of solvent dictated the formation of either the syn,anti or syn,syn diastereoisomers, two of the four possible diastereoisomers. The syn,syn isomer is a rare example of a syn-selective nitro-Mannich reaction. The diastereoselectivity is dependent upon the presence or not of Zn(O(2)CCF(3))(2) in the reaction mixture and empirical transition state models are proposed to account for the observed stereochemical course of the two reaction conditions. The extent of enantioselectivity and structural diversity of the process is limited by current methodology for the catalytic asymmetric addition of dialkylzincs to nitrostyrenes. The synthetically versatile products are the most complex β-nitro amines prepared using the nitro-Mannich reaction and are formed in high yield and enantioselectivity.

  9. Synthesis of BF₃ catalyzed Mannich derivatives with excellent ee from phenylpropanolamine, study of their antimicrobial activity and molecular docking.

    Science.gov (United States)

    Chennakesava Rao, K; Easwaramoorthi, K; Arun, Y; Balachandran, C; Muralidhara Rao, K S; Govindhan, M; Emi, Nobuhiko; Prakasam, T; Perumal, P T

    2015-10-01

    Antimicrobial agents 4a-g and 5a-g with very good potency were synthesized with 100% ee from phenylpropanolamine (norephedrine) by BF3 catalyzed three components one pot Mannich reaction in good yields. Obtained compounds were characterized using spectral techniques. Antimicrobial study of these compounds revealed a good to very high potential activity against tested microbes when compared to standard antimicrobial drugs streptomycin and ketoconazole. These synthesized compounds exhibited significant minimum inhibitory concentration (MIC) values against Gram positive and Gram negative bacteria. Amongst compound 4b, 4c, 4d, 4e, 5a, and 5e exhibited very high potent MIC values against tested twelve bacteria and three fungi when compared to control. When subjected to molecular docking, in silico studies revealed significant binding energies ranging from -7.06 to -8.90 kcal/mol for all obtained compounds towards target receptor DNA topoisomerase IV and amongst compounds 4b and 4d have shown maximum binding energies 8.70 and 8.90 kcal/mol, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. A New Highly Selective and Specific Anti-puerarin polyclonal Antibody for Determination of Puerarin Using a Mannich Reaction Hapten Conjugate.

    Science.gov (United States)

    Udomsin, Orapin; Krittanai, Supaluk; Kitisripanya, Tharita; Tanaka, Hiroyuki; Putalun, Waraporn

    2018-01-01

    Puerarin (PUE) is a phytoestrogen found in Pueraria candollei and Pueraria lobata. These plants are substantial for traditional medicine in various Asian countries. PUE is a key marker that can be found only in the Pueraria species. To establish the method for determination of PUE content which is required for quality control of pharmaceutical products. PUE-cationized bovine serum albumin conjugate was created via Mannich reaction. After the rabbit immunization, the obtain anti-PUE polyclonal antibody (PAb) was used to develop an enzyme-linked immunosorbent assay (ELISA). An anti-PUE PAb possess a great sensitivity and specificity. The cross-reactivity analysis shows no cross-reaction of an established antibody against other substances. In addition, we successfully developed an indirect competitive ELISA (icELISA) for the quantitative analysis of PUE. The result of method validation conforms to acceptance criteria and correlates with high-performance liquid chromatography, the reference method. The icELISA was applied to determine PUE content in Pueraria spp. plant samples and its derived pharmaceutical products. This highly specific immunogen was created from the Mannich reaction. An icELISA can also be applied to other research propose in the further studies. The new immunogen conjugated (puerarin-cBSA) via Mannich reaction was successfully in rising of antibody against puerarin (PUE)The obtained anti-PUE polyclonal antibody (PAb) was high sensitivity and specificity to PUEAn indirect competitive enzyme-linked immunosorbent assay (icELISA) was developed and validated using anti-PUE PAbThe established icELISA was applied to determine PUE content in various tuberous root of Pueraria sppMoreover, icELISA method can be applicable in Pueraria spp. derived products. Abbreviations used: PUE: Puerarin; PAb: Polyclonal antibody; ELISA: Enzyme-linked immunosorbent assay; icELISA: Indirect competitive ELISA; cBSA: Cationized bovine serum albumin.

  11. An efficient synthesis of β-amino ketone compounds through one-pot three-component Mannich-type reactions using bismuth nitrate as catalyst

    Directory of Open Access Journals (Sweden)

    S. Sheik Mansoor

    2015-07-01

    Full Text Available Three components one-pot Mannich reaction of aromatic ketone, aromatic aldehyde and aromatic amines has been efficiently catalyzed by recyclable bismuth nitrate (Bi(NO33, BN at ambient temperature to give various β-amino carbonyl compounds in high yields. This method has advantages of mild condition, no environmental pollution, and simple work-up procedures. Most importantly, β-amino carbonyl compounds with ortho-substituted aromatic amines are obtained in acceptable to moderate yields by this methodology.

  12. One-Pot Synthesis of Novel Chiral β-Amino Acid Derivatives by Enantioselective Mannich Reactions Catalyzed by Squaramide Cinchona Alkaloids

    Directory of Open Access Journals (Sweden)

    Kankan Zhang

    2013-05-01

    Full Text Available An efficient one-pot synthesis of novel β-amino acid derivatives containing a thiadiazole moiety was developed using a chiral squaramide cinchona alkaloid as organocatalyst. The reactions afforded chiral β-amino acid derivatives in moderate yields and with moderate to excellent enantioselectivities. The present study demonstrated for the first time the use of a Mannich reaction catalyzed by a chiral bifunctional organocatalyst for the one-pot synthesis of novel β-amino acid derivatives bearing a 1,3,4-thiadiazole moiety on nitrogen.

  13. Novel α-amino acid-derived phase-transfer catalyst application to a highly enantio- and diastereoselective nitro-Mannich reaction.

    Science.gov (United States)

    Liu, Yuxin; Wei, Zhonglin; Liu, Yu; Cao, Jungang; Liang, Dapeng; Lin, Yingjie; Duan, Haifeng

    2017-11-07

    New quaternary ammonium types of bifunctional asymmetric phase-transfer catalysts bearing multiple hydrogen-bonding donors derived from α-amino acids were readily prepared and found to be highly efficient in the asymmetric nitro-Mannich reactions of amidosulfones. Very broad substrate generality was observed, and the products were achieved in high enantio-/diastereoselectivities (90->99.9% ee, 90 : 10 to 92 : 8 dr). Compared with previous reports, the enantioselectivity of aliphatic amidosulfones has been improved to a high level (91-93% ee).

  14. γ'-Selective Functionalization of Cyclic Enones: Construction of a Chiral Quaternary Carbon Center by [4+2] Cycloaddition/Retro-Mannich Reaction with 3-Substituted Maleimides.

    Science.gov (United States)

    Zou, Chuncheng; Zeng, Chuikun; Liu, Zhen; Lu, Min; Sun, Xiaohua; Ye, Jinxing

    2016-11-07

    The first example of organocatalyzed γ'-selective functionalization of cyclic enones with 3-substituted maleimides results in the stereoselective construction quaternary carbon center is presented. The reactions provided γ'-functionalized cyclic enones and β-functionalized cyclopentenones in good to excellent yields with excellent diastereo- and enantioselectivities. DFT calculations indicated that the reaction might proceed as a [4+2] cycloaddition/retro-Mannich reaction which could explain the unexpected product with a chiral quaternary carbon center and the excellent stereoselectivity. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Asymmetric Ring Opening/Cyclization/Retro-Mannich Reaction of Cyclopropyl Ketones with Aryl 1,2-Diamines for the Synthesis of Benzimidazole Derivatives.

    Science.gov (United States)

    Xia, Yong; Lin, Lili; Chang, Fenzhen; Liao, Yuting; Liu, Xiaohua; Feng, Xiaoming

    2016-09-26

    A highly efficient asymmetric ring-opening/cyclization/retro-Mannich reaction of cyclopropyl ketones with aryl 1,2-diamines has been realized using a chiral N,N'-dioxide/Sc(III) catalyst. Benzimidazoles containing chiral side chains were generated under mild reaction conditions in excellent outcomes (up to 99 % yield and 97 % ee). This method also provides efficient access to chiral benzimidazole-substituted amide and cycloheptene derivatives. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Zn-ProPhenol Catalyzed Enantio- and Diastereoselective Direct Vinylogous Mannich Reactions between α,β- and β,γ-Butenolides and Aldimines.

    Science.gov (United States)

    Trost, Barry M; Gnanamani, Elumalai; Tracy, Jacob S; Kalnmals, Christopher A

    2017-12-20

    We report a Zn-ProPhenol catalyzed reaction between butenolides and imines to obtain tetrasubstituted vinylogous Mannich products in good yield and diastereoselectivity with excellent enantioselectivity (97 to >99.5% ee). Notably, both α,β- and β,γ-butenolides can be utilized as nucleophiles in this transformation. The imine partner bears the synthetically versatile N-Cbz group, avoiding the use of the specialized aryl directing groups previously required in related work. Additionally, the reaction can be performed on gram scale with reduced catalyst loading as low as 2 mol %. The functional group-rich products can be further elaborated using a variety of methods.

  17. Organocatalytic Asymmetric Mannich Reaction of 3-Hydroxyoxindoles/3-Aminooxindoles with in Situ Generated N-Boc-Protected Aldimines for the Synthesis of Vicinal Oxindole-Diamines/Amino Alcohols.

    Science.gov (United States)

    Shan, Jing; Cui, Baodong; Wang, Yu; Yang, Chengli; Zhou, Xiaojian; Han, Wenyong; Chen, Yongzheng

    2016-07-01

    A highly efficient asymmetric Mannich reaction of 3-monosubstituted 3-aminooxindoles/3-hydroxyoxindoles with in situ generated N-Boc-protected aldimines catalyzed by the chiral bifunctional thiourea-tertiary amine catalyst has been developed. Under mild reaction conditions, a series of structurally diverse vicinal oxindole-diamines/amino alcohols were smoothly obtained in moderate to high yields (up to 99%) with good to excellent diastereoselectivities and enantioselectivities (up to 95:5 dr and 96% ee). The synthetic application of this protocol was also demonstrated by the versatile transformation of chiral vicinal oxindole-diamine/amino alcohol into spirocyclic oxindoles.

  18. Specific Features of Intramolecular Proton Transfer Reaction in Schiff Bases

    Directory of Open Access Journals (Sweden)

    Aleksander Koll

    2003-06-01

    Full Text Available Abstract: The differences between the intramolecular proton transfer in Mannich and Schiff bases are discussed. The tautomeric forms being in equilibrium in both types of molecules are seriously different. In Mannich bases there are in equilibrium the forms of phenols and phenolates. In Schiff bases each of tautomers is strongly influenced by resonance between zwitterionic and keto structures. Despite the common opinion that the proton transfer forms in compounds with internal π-electronic coupling are mainly keto forms it is shown in this work, that in Schiff bases the content of keto structure is slightly less than zwitterionic one. Almost equal participation of both forms leads to effective resonance between them and stabilization of intramolecular hydrogen bond in this way.

  19. Novel ionic liquid supported on Fe3O4nanoparticles and its application as a catalyst in Mannich reaction under ultrasonic irradiation.

    Science.gov (United States)

    Safaei Ghomi, Javad; Zahedi, Safura

    2017-01-01

    A family of novel ionic liquid with l-alanine and choline chloride as environmentally benign materials have been synthesized and grafted on Fe 3 O 4 nanoparticles using easy preparation techniques. The structure of ionic liquid supported on Fe 3 O 4 nanoparticles (IL-Fe 3 O 4 NPs) characterized by various analyses such as FE-SEM, EDX, XRD, NMR, FTIR and VSM. The catalytic activities of this catalyst are examined in the Mannich reaction for synthesis of β-aminocarbonyl compounds under ultrasonic irradiation. The recyclability of catalyst is investigated, and the results have indicated that the catalyst can be recycled six times without obvious activity decreasing. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Design and synthesis of pyrido[2,1-b][1,3,5]thiadiazine library via uncatalyzed Mannich-type reaction.

    Science.gov (United States)

    Dotsenko, Victor V; Frolov, Konstantin A; Pekhtereva, Tatyana M; Papaianina, Olena S; Suykov, Sergey Yu; Krivokolysko, Sergey G

    2014-10-13

    This Research Article describes the synthesis of an over 700-member library of (8R/8S)-3-R-8-aryl-6-oxo-3,4,7,8-tetrahydro-2H,6H-pyrido[2,1-b][1,3,5]thiadiazin-9-carbonitriles by uncatalyzed Mannich-type reaction of N-methylmorpholinium (4R/4S)-4-aryl-3-cyano-6-oxo-1,4,5,6-tetrahydropyridin-2-thiolates with a set of primary amines and excessive HCHO. The scope and limitations of the reaction were studied. Starting thiolates were obtained in yields of 53-82% by multicomponent reaction of aromatic aldehydes, cyanothioacetamide, 2,2-dimethyl-1,3-dioxane-4,6-dione (Meldrum's acid), and N-methylmorpholine, followed by heterocyclization of the resulting Michael adducts.

  1. Cinchona Alkaloid Derivative-Catalyzed Enantioselective Synthesis via a Mannich-Type Reaction and Antifungal Activity of β-Amino Esters Bearing Benzoheterocycle Moieties

    Directory of Open Access Journals (Sweden)

    Han Xiao

    2014-04-01

    Full Text Available An efficient synthesis of highly functionalized chiral β-amino ester derivatives containing benzothiophene and benzothiazole moieties is developed by a Mannich-type reaction using a cinchona alkaloid-derived thiourea catalyst. The desired products were obtained in good yields and high enantioselectivities (~86% yield, >99% ee using to the optimized reaction conditions. The synthesized compounds were characterized by 1H-NMR, 13C-NMR, IR, and HREI-MS analyses. The bioassays identified that compound 5dr has excellent antifungal activity, with a 60.53% inhibition rate against F. oxysporum, higher than that of the commercial agricultural fungicide hymexazol, whose inhibition rate was 56.12%.

  2. Catalytic asymmetric mannich-type reaction of N-alkylidene-α-aminoacetonitrile with ketimines.

    Science.gov (United States)

    Lin, Shaoquan; Kawato, Yuji; Kumagai, Naoya; Shibasaki, Masakatsu

    2015-04-20

    Optically active vicinal diamines are versatile chiral building blocks in organic synthesis. A soft Lewis acid/hard Brønsted base cooperative catalyst allows for an efficient stereoselective coupling of N-alkylidene-α-aminoacetonitrile and ketimines to access this class of compounds bearing consecutive tetra- and trisubstituted stereogenic centers. The strategic use of a soft Lewis basic thiophosphinoyl group for ketimines is the key to promoting the reaction, and aliphatic ketimines serve as suitable substrates with as little as 3 mol % catalyst loading. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Asymmetric synthesis of γ-chloro-α,β-diamino- and β,γ-aziridino-α-aminoacylpyrrolidines and -piperidines via stereoselective Mannich-type additions of N-(diphenylmethyleneglycinamides across α-chloro-N-sulfinylimines

    Directory of Open Access Journals (Sweden)

    Gert Callebaut

    2012-12-01

    Full Text Available The asymmetric synthesis of new chiral γ-chloro-α,β-diaminocarboxylamide derivatives by highly diastereoselective Mannich-type reactions of N-(diphenylmethyleneglycinamides across chiral α-chloro-N-p-toluenesulfinylaldimines was developed. The resulting (SS,2S,3S-γ-chloro-α,β-diaminocarboxylamides were formed with the opposite enantiotopic face selectivity as compared to the (SS,2R,3R-γ-chloro-α,β-diaminocarboxyl esters obtained via Mannich-type addition of analogous N-(diphenylmethyleneglycine esters across a chiral α-chloro-N-p-toluenesulfinylaldimine. Selective deprotection under different acidic reaction conditions and ring closure of the γ-chloro-α,β-diaminocarboxylamides was optimized, which resulted in Nα-deprotected syn-γ-chloro-α,β-diaminocarboxylamides, N-sulfinyl-β,γ-aziridino-α-aminocarboxylamide derivatives, a trans-imidazolidine, and an Nα,Nβ-deprotected syn-γ-chloro-α,β-diaminocarboxylamide.

  4. Reações multicomponentes de Biginelli e de Mannich nas aulas de química orgânica experimental: uma abordagem didática de conceitos da química verde

    OpenAIRE

    Marques, Marcelo Volpatto; Bisol, Tula Beck; Sá, Marcus Mandolesi

    2012-01-01

    The introduction of Mannich and Biginelli multicomponent reactions in a practical Organic Chemistry course is presented in this article. Procedures described in the literature were adapted for use under the simple conditions available in undergraduate laboratories and were selected on the basis of Green Chemistry principles and practicality of synthesis. The reactions are easy to carry out and all products are readily isolated as crystalline solids with yields ranging from moderate to high.

  5. Cerium chloride (CeCl{sub 3{center_dot}}7H{sub 2}O) as a highly efficient catalyst for one-pot three-component Mannich reaction

    Energy Technology Data Exchange (ETDEWEB)

    Kidwai, Mazaahir; Anwar, Jahan, E-mail: kidwai.chemistry@gmail.co [University of Delhi (India). Dept. of Chemistry. Green Chemistry Research Lab.

    2010-07-01

    We have demonstrated the use of CeCl{sub 3{center_dot}}7H{sub 2}O as highly efficient catalyst for one-pot three component Mannich reaction to afford beta-amino carbonyl compounds in good to excellent yield within shorter period of reaction time. The process is mild, efficient, environmentally benign with the use of little amount of catalyst. (author)

  6. An asymmetric organocatalytic vinylogous Mannich reaction of 3-methyl-5-arylfuran-2(3H)-ones with N-(2-pyridinesulfonyl) imines: enantioselective synthesis of δ-amino γ,γ-disubstituted butenolides.

    Science.gov (United States)

    Wang, Zhen-Hua; You, Yong; Chen, Yong-Zheng; Xu, Xiao-Ying; Yuan, Wei-Cheng

    2018-03-07

    An asymmetric organocatalytic vinylogous Mannich reaction of 3-methyl-5-arylfuran-2(3H)-ones with N-(2-pyridinesulfonyl)imines has been developed with 5 mol% thiourea-tertiary amine as the catalyst. A series of δ-amino γ,γ-disubstituted butenolides bearing adjacent quaternary and tertiary stereocenters are efficiently obtained with satisfactory results (up to 90% yield, 90 : 10 dr, and 95 : 5 er).

  7. Reações multicomponentes de Biginelli e de Mannich nas aulas de química orgânica experimental: uma abordagem didática de conceitos da química verde

    Directory of Open Access Journals (Sweden)

    Marcelo Volpatto Marques

    2012-01-01

    Full Text Available The introduction of Mannich and Biginelli multicomponent reactions in a practical Organic Chemistry course is presented in this article. Procedures described in the literature were adapted for use under the simple conditions available in undergraduate laboratories and were selected on the basis of Green Chemistry principles and practicality of synthesis. The reactions are easy to carry out and all products are readily isolated as crystalline solids with yields ranging from moderate to high.

  8. Novel 3-(aminomethyl)naphthoquinone mannich base-platinum(IV) complexes: synthesis, characterization, electrochemical and cytotoxic studies

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Gustavo B. da; Neves, Amanda P.; Vargas, Maria D., E-mail: mdvargas@vm.uff.br [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Instituto de Quimica; Alves, Wagner A. [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil). Departamento de Quimica; Marinho-Filho, Jose D.B.; Pessoa, Claudia; Moraes, Manoel O.; Costa-Lotufo, Leticia V. [Universidade Federal do Ceara (UFCE), Fortaleza, CE (Brazil). Centro de Ciencias da Saude. Departamento de Fisiologia e Farmacologia

    2013-04-15

    Three novel platinum(IV) complexes cis,cis,trans-[Pt(HL1-3)Cl{sub 2}(OH){sub 2}] 1b-3b(HL = 2-hydroxy-3-[(R{sup 1} -amino)(pyridin-2-yl)methyl]-1,4-naphthoquinone, R{sup 1} = n-butyl, HL1; n-heptyl, HL2 and n-decyl, HL3) have been obtained from the oxidation of the respective precursors cis-[Pt(HL1-3)Cl{sub 2}] 1a-3a. Cyclic voltammetry studies of 1b-3b in MeCN showed the quasi reversible naphthoquinonate (NQO{sup -}, i.e., L{sup -}) redox process and irreversible process attributed to the reduction of the Pt{sup 4+}/Pt{sup 2+} pair, at potentials about 400 mV less negative than for the cisplatin precursor cis,cis,trans-[Pt(NH{sub 3}){sub 2}Cl{sub 2}(OH){sub 2}]. Hydrogen bond interaction between the naphthoquinone 2-hydroxyl group and an axially coordinated hydroxide ligand in 1b-3b has been proposed to favor the Pt{sup 4+}/Pt{sup 2+} reduction. The cytotoxicity studies against four human cancer cell lines have shown that in general the platinum(IV) and platinum(II)derivatives exhibit the same cytotoxic profile and are all more active than cisplatin. The lowest in vitro IC{sub 50} values have been observed for 2b-3b, which bear ligands with the largest R{sup 1} groups (HL2-HL3) being the most lipophilic. Furthermore similar IC{sub 50} values for platinum(II) and platinum(IV) complexes of the same ligands have been associated with rapid in vitro reduction of the latter complexes to afford 1a-3a. (author)

  9. In Vitro and in Vivo Anti-Trypanosoma cruzi Activity of New Arylamine Mannich Base-Type Derivatives.

    Science.gov (United States)

    Moreno-Viguri, Elsa; Jiménez-Montes, Carmen; Martín-Escolano, Rubén; Santivañez-Veliz, Mery; Martin-Montes, Alvaro; Azqueta, Amaya; Jimenez-Lopez, Marina; Zamora Ledesma, Salvador; Cirauqui, Nuria; López de Ceráin, Adela; Marín, Clotilde; Sánchez-Moreno, Manuel; Pérez-Silanes, Silvia

    2016-12-22

    Chagas disease is a neglected tropical disease with 6-7 million people infected worldwide, and there is no effective treatment. Therefore, there is an urgent need to continue researching in order to discover novel therapeutic alternatives. We present a series of arylaminoketone derivatives as means of identifying new drugs to treat Chagas disease in the acute phase with greater activity, less toxicity, and a larger spectrum of action than that corresponding to the reference drug benznidazole. Indexes of high selectivity found in vitro formed the basis for later in vivo assays in BALB/c mice. Murine model results show that compounds 3, 4, 7, and 10 induced a remarkable decrease in parasitemia levels in acute phase and the parasitemia reactivation following immunosuppression, and curative rates were higher than with benznidazole. These high antiparasitic activities encourage us to propose these compounds as promising molecules for developing an easy to synthesize anti-Chagas agent.

  10. Novel 3-(aminomethyl)naphthoquinone mannich base-platinum(IV) complexes: synthesis, characterization, electrochemical and cytotoxic studies

    International Nuclear Information System (INIS)

    Silva, Gustavo B. da; Neves, Amanda P.; Vargas, Maria D.; Alves, Wagner A.; Marinho-Filho, Jose D.B.; Pessoa, Claudia; Moraes, Manoel O.; Costa-Lotufo, Leticia V.

    2013-01-01

    Three novel platinum(IV) complexes cis,cis,trans-[Pt(HL1-3)Cl 2 (OH) 2 ] 1b-3b(HL = 2-hydroxy-3-[(R 1 -amino)(pyridin-2-yl)methyl]-1,4-naphthoquinone, R 1 = n-butyl, HL1; n-heptyl, HL2 and n-decyl, HL3) have been obtained from the oxidation of the respective precursors cis-[Pt(HL1-3)Cl 2 ] 1a-3a. Cyclic voltammetry studies of 1b-3b in MeCN showed the quasi reversible naphthoquinonate (NQO - , i.e., L - ) redox process and irreversible process attributed to the reduction of the Pt 4+ /Pt 2+ pair, at potentials about 400 mV less negative than for the cisplatin precursor cis,cis,trans-[Pt(NH 3 ) 2 Cl 2 (OH) 2 ]. Hydrogen bond interaction between the naphthoquinone 2-hydroxyl group and an axially coordinated hydroxide ligand in 1b-3b has been proposed to favor the Pt 4+ /Pt 2+ reduction. The cytotoxicity studies against four human cancer cell lines have shown that in general the platinum(IV) and platinum(II)derivatives exhibit the same cytotoxic profile and are all more active than cisplatin. The lowest in vitro IC 50 values have been observed for 2b-3b, which bear ligands with the largest R 1 groups (HL2-HL3) being the most lipophilic. Furthermore similar IC 50 values for platinum(II) and platinum(IV) complexes of the same ligands have been associated with rapid in vitro reduction of the latter complexes to afford 1a-3a. (author)

  11. A highly efficient Mukaiyama-Mannich reaction of N-Boc isatin ketimines and other active cyclic ketimines using difluoroenol silyl ethers catalyzed by Ph3PAuOTf.

    Science.gov (United States)

    Yu, Jin-Sheng; Zhou, Jian

    2015-12-07

    Ph3PAuOTf is identified as a powerful catalyst for the addition of difluoroenol silyl ethers to N-Boc isatin ketimines and other two kinds of active cyclic ketimines. This represents the first Au(i)-catalyzed Mukaiyama-Mannich reaction, and the corresponding non-fluorinated enol silyl ether proves to be even much more reactive under the same conditions. This method paves the way to the total synthesis of difluoromethylated analogues of AG-041R, a gastrin/CCK-B receptor antagonist.

  12. A Laccase-catalysed one-pot synthesis of aminonaphthoquinones and their anticancer activity

    CSIR Research Space (South Africa)

    Wellington, Kevin W

    2012-05-01

    Full Text Available has been adopted for this screen. Materials and method The human cell lines TK10, UACC62 and MCF7 were obtained from the NCI in a collaborative research program between the CSIR and the NCI. Cell lines were routinely maintained as a monolayer... cell culture at 37?C, 5% CO2, 95% air and 100% relative humidity in RPMI containing 5% fetal bovine serum, 2 mM L-glutamine and 50?g/ml gentamicin. For the screening experiment the cells (3-19 passages) were inoculated in a 96-well microtiter...

  13. Asymmetric synthesis of syn-propargylamines and unsaturated β-amino acids under Brønsted base catalysis

    Science.gov (United States)

    Wang, Yingcheng; Mo, Mingjie; Zhu, Kongxi; Zheng, Chao; Zhang, Hongbin; Wang, Wei; Shao, Zhihui

    2015-01-01

    Propargylamines are important intermediates for the synthesis of polyfunctional amino derivatives and natural products and biologically active compounds. The classic method of synthesizing chiral propargylamines involves the asymmetric alkynylation of imines. Here, we report a significant advance in the catalytic asymmetric Mannich-type synthesis of propargylamines through catalytic asymmetric addition of carbon nucleophiles to C-alkynyl imines, culminating in a highly syn-selective catalytic asymmetric Mannich reaction of C-alkynyl imines that provide syn-configured propargylamines with two adjacent stereogenic centres and a transition metal-free organocatalytic asymmetric approach to β-alkynyl-β-amino acids with high efficiency and practicality, via a chiral Brønsted base-catalysed asymmetric Mannich-type reaction of in situ generated challenging N-Boc C-alkynyl imines from previously unreported C-alkynyl N-Boc-N,O-acetals, with α-substituted β-keto esters and less-acidic malonate (thio)esters as nucleophiles, respectively. A catalytic activation strategy is also disclosed, which may have broad implications for use in catalysis and synthesis. PMID:26423837

  14. Quantum chemical calculations and molecular docking studies of 5-(4-chlorobenzylidene)thiazolidine-2,4-dione(CTD) and its mannich product 5-(4-chlorobenzylidene)-3-(morpholinomethyl)thiazolidine-2,4-dione (CMTD)

    Science.gov (United States)

    Fatma, Shaheen; Bishnoi, Abha; Verma, Anil Kumar; Singh, Vineeta; Srivastava, Krishna

    2018-04-01

    This work presents the synthesis of 5-(4-chlorobenzylidene)thiazolidine-2,4-dione (CTD) by Claisen condensation of thiazolidine-2,4-dione and mannich product of CTD, 5-(4-chlorobenzylidene)-3-(morpholinomethyl)thiazolidine-2,4-dione (CMTD). The static first hyperpolarizability values for thiazolidine-2,4-dione derivatives have been calculated as 10.28 × 10-30 esu for CTD and 19.42 × 10-30 esu for CMTD. The gradual increase in hyperpolarizability values of synthesized thiazolidine-2,4-dione derivatives from CTD to CMTD is due to the blockage of sbnd NH group on CTD by mannich reaction. The structures of these compounds have been derived by spectroscopic(IR, UV, Mass, 1H and 13C NMR) analysis as well as with the help of theoretical studies. The high values of first static hyperpolarizability indicate that the synthesized derivatives are suitable as non-linear optical (NLO) material. CTD with MIC value of 12.5 μg/mL can be developed as an alternative drug for the treatment of enteric fever. Calculated frontier orbital gap values suggest that the CMTD is a soft molecule with high chemical reactivity and is more polarizable as compared to the CTD. Molecular electrostatic potential is calculated for the optimized geometry of the molecules to estimate their chemical reactivity. The inhibitor CTD forms a stable complex with 3-dehydroquinase enzyme of Salmonella typhi. It is evident from the ligand receptor interactions and a binding affinity value of -5.88 kcal/mol and an inhibition constant of 49.22 μM. This is further confirmed by the experimental biological data. The molecular docking studies are supportive of the antibacterial activity of CTD exhibiting high inhibition constant and binding energy.

  15. Intramolecular hydrogen bond in molecular and proton-transfer forms of Schiff bases

    Energy Technology Data Exchange (ETDEWEB)

    Filarowski, A.; Koll, A.; Karpfen, A.; Wolschann, P

    2004-02-16

    The force field and structural parameters modifications upon the formation of intramolecular hydrogen bond and proton transfer reaction in N-methyl-2-hydroxybenzylidene amine (HBZA) are determined on the basis of ab initio and DFT calculations. Reliability of the calculations is verified by comparing of the theoretical vibrational spectra with those experimentally determined in the gas phase. A model of resonance interactions is applied and the quantitative contribution of ortho-quinoid structure in the particular conformers is estimated. A comparison is also made to the systems without {pi}-electron coupling (Mannich bases)

  16. Tannin based flocculants

    OpenAIRE

    Tišler, Vesna; Golob, Gabrijela; Rutar, Vera

    2002-01-01

    Various kinds of tannin flocculants were synthesised using spruce tannin, spruce-fir tannin, oak tannin, mimosa tannin, aleppo pine tannin, quebracho tannin, with suitable chemicals. Cationic flocculants were obtained on the basis of the Mannich reaction performed at constant mixing and constant temperature. The testing of flocculants was performed by standardised flock tester. Zeta potentials were measured using Laser Zeetm 501 zeta meter.

  17. Novel Phenolic 1-aryl-3-arylamino-1-propanones: Synthesis and Characterization

    Directory of Open Access Journals (Sweden)

    Roman Gheorghe

    2017-12-01

    Full Text Available A small collection of 1-aryl-3-arylamino-1-propanones having a phenolic moiety in their structure has been obtained by the replacement of the tertiary amino group in ketonic Mannich bases with (heteroaromatic amines. The installment of the phenolic moiety took place either through the N-alkylation of 4-aminophenol with ketonic Mannich base hydrochlorides, or via amine exchange in ketonic Mannich bases derived from either 2′-hydroxyacetophenone or 4′-hydroxyacetophenone.

  18. SYNTHESIS OF TETRAKIS-N,N,N-TRIMETHYLAMMONIUMMETHYL-C-3,4-DIMETHOXYPHENYLCALIX[4]RESORCINARENE IODIDE BASED VANILLIN AND ITS ANTIDOTE ACTIVITY FOR CHROMIUM(VI INTOXICATION

    Directory of Open Access Journals (Sweden)

    Suryadi Budi Utomo

    2013-08-01

    Full Text Available A research has been conducted to synthesize tetrakis-N,N,N-trimethylammoniummethyl-C-3,4-dimethoxyphenylcalix[4]resorcinarene iodide from vanillin and investigate its antidote capability for Cr(VI intoxication. The synthesis was carried out in four steps i.e. (1 O-alkylation of 4-hydroxy-3-methoxybenzaldehyde, (2 HCl-catalyzed condensation of 3,4-dimethoxybenzaldehyde with resorcinol, (3 Mannich reaction of C-3,4-dimethoxyphenylcalix[4]resorcinarene with formaldehyde and dimethylamine in the presence of HCl to yield tetrakis-N,N-dimethylaminomethyl-C-3,4-dimethoxyphenylcalix[4]resorcinarene, and (4 treatment the Mannich base with methyl iodide to produce the quaternary ammonium salt of tetrakis-N,N,N-trimethylammoniummethyl-C-3,4-dimethoxyphenylcalix[4]resorcinarene iodide. According to the analysis of 1H-NMR spectrometer, the targeted compounds tend to exist in the chair (C2h conformation. The capability of resorcinarene for Cr(VI antidote was examined by orally injection method on mice groups. Based on LD50 determination, the resorcinarene was classified as non toxic compound according to Loomis criteria. Therapeutic using quaternary ammonium-modified resorcinarene was able to reduce metal concentrations of Cr(VI in liver, kidney, and serum in the magnitude of 78.30; 85.72, and 88.79%, respectively. The higher dose of drug administered the greater decrease in the level of heavy metal. Judging from the amount of milligrams of reduced chromium per gram of organ, kidney is the organ having highest decreasing metal concentrations.

  19. Tannin based flocculants

    OpenAIRE

    Tišler, Vesna; Golob, Gabrijela; Rutar, Vera

    2002-01-01

    Various kinds of tannin flocculants were synthesised using spruce tannin, spruce-fir tannin, oak tannin, mimosa tannin, aleppo pine tannin, quebracho tannin, with suitable chemicals. Cationic flocculants were obtained on the basis of the Mannich reaction performed at constant mixing and constant temperature. The testing of flocculants was performed by standardised flock tester. Zeta potentials were measured using Laser Zeetm 501 zeta meter. Sintetizirali smo flokulante iz različnih vrst ta...

  20. Fulltext PDF

    Indian Academy of Sciences (India)

    Unknown

    Expoxidation and oxidation reactions using 1,4-buta- nediol dimethacrylate crosslined polystyrene-supported .... Mannich base. A new Mannich base and its transition metal (II) com- plexes – Synthesis, structural characterization and ele- ctrochemical study. 209. Mechanism. Kinetics and mechanism of polymerization of ...

  1. Nematicidal, larvicidal and antimicrobial activities of some new ...

    African Journals Online (AJOL)

    Purpose: To synthesize Mannich base imidazole derivatives, and evaluate their antimicrobial, nematicidal and larvicidal properties . Methods: Compounds 1a-g and 2a-g were prepared using a Mannich condensation method. The chemical structures of compounds 2a-g were confirmed by Fourier transform infrared ...

  2. Base

    DEFF Research Database (Denmark)

    Hjulmand, Lise-Lotte; Johansson, Christer

    2004-01-01

    BASE - Engelsk basisgrammatik er resultatet af Lise-Lotte Hjulmands grundige bearbejdning og omfattende revidering af Christer Johanssons Engelska basgrammatik. Grammatikken adskiller sig fra det svenske forlæg på en lang række punkter. Den er bl.a. tilpasset til et dansk publikum og det danske...

  3. Refined transition-state models for proline-catalyzed asymmetric Michael reactions under basic and base-free conditions.

    Science.gov (United States)

    Sharma, Akhilesh K; Sunoj, Raghavan B

    2012-12-07

    The stereocontrolling transition state (TS) models for C-C bond formation relying on hydrogen bonding have generally been successful in proline-catalyzed aldol, Mannich, α-amination, and α-aminoxylation reactions. However, the suitability of the hydrogen-bonding model in protic and aprotic conditions as well as under basic and base-free conditions has not been well established for Michael reactions. Through a comprehensive density functional theory investigation, we herein analyze different TS models for the stereocontrolling C-C bond formation, both in the presence and absence of a base in an aprotic solvent (THF). A refined stereocontrolling TS for the Michael reaction between cyclohexanone and nitrostyrene is proposed. The new TS devoid of hydrogen bonding between the nitro group of nitrostyrene and carboxylic acid of proline, under base-free conditions, is found to be more preferred over the conventional hydrogen-bonding model besides being able to reproduce the experimentally observed stereochemical outcome. A DBU-bound TS is identified as more suitable for rationalizing the origin of asymmetric induction under basic reaction conditions. In both cases, the most preferred approach of nitrostyrene is identified as occurring from the face anti to the carboxylic acid of proline-enamine. The predicted enantio- and diastereoselectivities are in very good agreement with the experimental observations.

  4. [Acid-base catalysis of chiral Pd complexes: development of novel asymmetric reactions].

    Science.gov (United States)

    Hamashima, Yoshitaka

    2005-10-01

    Using a unique character of the chiral palladium complexes 1 and 2, several types of novel catalytic asymmetric reactions have been developed. In contrast to the conventional Pd(0)-catalyzed reactions, these complexes function as an acid-base catalyst. Thus active methine compounds were activated to form chiral palladium enolates, which underwent the enantioselective Michael reaction and Mannich-type reaction with up to 99% ee. Interestingly, these palladium enolates acted cooperatively with a strong protic acid activating the electrophiles, formed concomitantly during the formation of the enolates, whereby the C-C bond-forming reaction was promoted. In addition, this palladium enolate chemistry was also applicable to the electrophilic asymmetric fluorination reactions, and thus various carbonyl compounds including beta-ketoesters, beta-ketophosphonates, and oxindoles were fluorinated in a highly enantioselective manner (up to 98% ee). It is advantageous that these reactions were carried out in environmentally friendly alcoholic solvents such as ethanol, and exclusion of air and moisture is not necessary.

  5. Tunable properties of novel tetra-functional fluorene-based benzoxazines from mixed amines: Synthesis, characterization and curing kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Tiantian [Polymer Materials Research Center, Key Laboratory of Superlight Material and Surface Technology of Ministry of Education, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 15001 (China); Wang, Jun, E-mail: wj6267@sina.com [Polymer Materials Research Center, Key Laboratory of Superlight Material and Surface Technology of Ministry of Education, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 15001 (China); Pan, Lan; Derradji, Mehdi; Ramdani, Noureddine [Polymer Materials Research Center, Key Laboratory of Superlight Material and Surface Technology of Ministry of Education, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 15001 (China); Liu, Wenbin, E-mail: wjlwb@163.com [Polymer Materials Research Center, Key Laboratory of Superlight Material and Surface Technology of Ministry of Education, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 15001 (China); Zhou, Haoran [Department of Polymer Materials and Engineering, College of Materials Science and Engineering, Harbin University of Science and Technology, Harbin 150040 (China)

    2016-06-10

    Highlights: • Synthesis of tetra-functional fluorene-based benzoxazines with tunable properties. • Cure reaction could be successfully described with the autocatalytic model. • The benzoxazines show an excellent heat resistance with T{sub g} of 291–307 °C. • The benzoxazines exhibit good thermal stability with T{sub 5} over 340 °C. - Abstract: A series of tetra-functional fluorene-based benzoxazines containing both flexible linear aliphatic chain and rigid aromatic structure in their backbones were synthesized using mixed amines such as aniline and n-octylamine, 2,7-dihydroxy-9,9-bis-(4-hydroxyphenyl)fluorene (THPF) and paraformaldehyde as raw materials via Mannich reaction. The prepared benzoxazine monomers were identified by fourier transform infrared spectroscopy (FTIR), hydrogen nuclear magnetic resonance ({sup 1}H NMR). In addition, the curing behavior, curing kinetics and rheological properties of these monomers as well as the thermal and mechanical properties of their cured resins were studied using a rheometer, differential scanning calorimeter (DSC), thermogravimetric analyzer (TGA), and dynamic thermomechanical analyzer (DMA). The newly developed benzoxazines show good processibility, excellent thermal stability and high glass transition temperature (T{sub g}) values ranging from 291 to 307 °C. By varying the proportion of n-octylamine to aniline, the properties of these resins are tuned.

  6. Mannich reaction: A versatile and convenient approach to bioactive ...

    Indian Academy of Sciences (India)

    The development of new drugs and target specific delivery agents with enhanced efficacy is essential to counter the multi-drug resistant (MDR) tumours1a,b and microbial strains. The modification of an existing drug molecules offers a cost and time effective conve- nient strategy to achieve new bioactive skeletons. Man-.

  7. Synthetic versatility of 2-substituted-6-methyl 2,3-dihydropyridinones in the synthesis of polyfunctional piperidine-based compounds and related β amino acid derivatives.

    Science.gov (United States)

    Yang, Yang; Hardman, Clayton

    2017-10-18

    Chiral 2-substituted-6-methyl 2,3-dihydropyidinones 9, which can be facilely obtained from an asymmetric vinylogous Mannich reaction (VMR) with 1,3-bis-trimethysily enol ether, were used as versatile intermediates in constructing chiral polyfunctional piperidine-based compounds. The 6-methyl group of such compounds can be conveniently functionalized via alkylation and acylation reactions to provide efficient entries to the synthesis of a variety of chiral multi-substituted piperidine-based compounds. Further elaboration of the corresponding intermediates also provided access to polyfunctional indolizidine-based compounds. These methods were showcased in an asymmetric synthesis of 2,6-di-substituted piperidine compound 13, reported as the key intermediate in the synthesis of (+)-calvine and a natural alkaloid (-)-indolizidine 209D. Furthermore, selective C5 iodination of compound 9 enabled the installation of additional functional groups at this position. Finally, we demonstrated that the oxidative cleavage of 2-substituted-6-methyl-2,3-dihydropyidinones is a practical and efficient method for the enantioselective synthesis of β-amino acids, which can undergo further intra-molecular cyclization to give the corresponding chiral four-membered β-lactam derivatives.

  8. Synthesis of task specific and reusable protic ionic liquids for one-pot multicomponent syntheses

    Science.gov (United States)

    Sardar, Sabahat; Wilfred, Cecilia Devi; Marc, Leveque Jean

    2016-11-01

    Protic ionic liquids (ILs) synthesized from 1-methylimidazole with 1,3-propane sultone and 1,4-butane sultone catalyzed Mannich reaction at 25 °C to afford Mannich bases in high yield (76%) and less time duration (20 min). Ionic liquids have been used as dual reagent i.e., as catalyst as well as solvent. Simple extraction by water separated ionic liquid from reaction mixture with 4 times recycling without any significant loss in activity.

  9. Benzylidene/2-aminobenzylidene hydrazides: Synthesis, characterization and in vitro antimicrobial evaluation

    Directory of Open Access Journals (Sweden)

    Manav Malhotra

    2014-11-01

    Full Text Available In this study a series of new mannich bases were synthesized and characterized by elemental and spectral (IR, 1H NMR, 13C NMR studies. All the synthesized compounds were evaluated for their antimicrobial activity by broth dilution method against two Gram negative strains (Escherichia coli and Pseudomonas aeruginosa, two Gram positive strains (Bacillus subtilis and Staphylococcus aureus and fungal strain (Candida albicans and Aspergillus niger. Preliminary pharmacological evaluation revealed that the compounds (3f, 3i, 3j, and 3k showed good activity against these strains. The result demonstrates the potential and importance of developing new mannich bases which would be effective against resistant bacterial and fungal strain.

  10. Synthesis and Antifungal Evaluation of 1-Aryl-2-dimethyl-aminomethyl-2-propen-1-one Hydrochlorides

    Directory of Open Access Journals (Sweden)

    Mehmet Emin Topaloglu

    2011-06-01

    Full Text Available The development of resistance to current antifungal therapeutics drives the search for new effective agents. The fact that several acetophenone-derived Mannich bases had shown remarkable antifungal activities in our previous studies led us to design and synthesize some acetophenone-derived Mannich bases, 1-8 and 2-acetylthiophene-derived Mannich base 9, 1-aryl-2-dimethylaminomethyl-2-propen-1-one hydrochloride, to evaluate their antifungal activities. The designed chemical structures have α,β-unsaturated ketone moieties, which are responsible for the bioactivities of the Mannich bases. The aryl part was C6H5 (1; 4-CH3C6H4 (2; 4-CH3OC6H4 (3; 4-ClC6H4 (4; 4-FC6H4 (5; 4-BrC6H4 (6; 4-HOC6H4 (7; 4-NO2C6H4 (8; and C4H3S(2-yl (9. In this study the designed compounds were synthesized by the conventional heating method and also by the microwave irradiation method to compare these methods in terms of reaction times and yields to find an optimum synthetic method, which can be applied for the synthesis of Mannich bases in further studies. Since there are limited number of studies reporting the synthesis of Mannich bases by microwave irradiation, this study may also contribute to the general literature on Mannich bases. Compound 7 was reported for the first time. Antifungal activities of all compounds and synthesis of the compounds by microwave irradiation were also reported for the first time by this study. Fungi (15 species were used for antifungal activity test. Amphotericin B was tested as an antifungal reference compound. In conclusion, compounds 1-6, and 9, which had more potent (2–16 times antifungal activity than the reference compound amphotericin B against some fungi, can be model compounds for further studies to develop new antifungal agents. In addition, microwave irradiation can be considered to reduce reaction period, while the conventional method can still be considered to obtain compounds with higher reaction yields in the synthesis of

  11. ALDOL- AND MANNICH-TYPE REACTIONS VIA IN SITU OLEFIN MIGRATION IN IONIC LIQUID. (R828129)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  12. On the effect of certain substituents in aromatic oxyketones on the direction of the Mannich reaction

    Energy Technology Data Exchange (ETDEWEB)

    Kuliyev, A.M.; Agamaliyeva, M.M.; Sardarova, S.A.

    1981-01-01

    Aminomethylation is done of 3-methyl-4-oxy- and 3-chlor-4-oxyacetophenones and 4-oxybenzophenone by secondary amines and formaldehyde. As the secondary amines are used dimethylamine, piperidine and morpholine. The reaction is conducted in benzene at 35-40/sup 0/. The composition and structure of the synthesized products are studied using elementary analysis, and their paramagnetic resonance and infrared spectra are recorded. It is shown that in the basic medium the reaction occurs only by the phenol function in the o-position to the OH group.

  13. C5-Morpholinomethylation of N1-sulfonylcytosines by a one-pot microwave assisted Mannich reaction.

    Science.gov (United States)

    Matić, Josipa; Nekola, Irena; Višnjevac, Aleksandar; Kobetić, Renata; Martin-Kleiner, Irena; Kralj, Marijeta; Žinić, Biserka

    2018-03-26

    A fast and efficient route for the introduction of a methylene bridged-amine (morpholinomethyl) functionality in the C5 position of the sulfonylated cytosine nucleobase has been developed. First, novel N1-sulfonylcytosine derivatives 3-6 were prepared by the condensation of silylated cytosine with selected sulfonyl chlorides. They were subsequently transformed to 5-morpholinomethyl-N1-sulfonylcytosine derivatives (8, 12-15) using microwave irradiation. As a result of cytosine ring opening in N1-tosylcytosine, depending on the reaction conditions, peculiar tosyl-urea derivative 9 has been isolated, which provided additional insight into the reaction pathway. The influence of the C5-substituent on the antiproliferative activity has been evaluated by performing the MTT test on U251, MCF-7 and MOLT-4 tumor cell-lines.

  14. Fulltext PDF

    Indian Academy of Sciences (India)

    A three-component Mannich-type reaction of aromatic aldehydes, ketones, and amines was catalyzed by a novel choline-based acidic ionic liquid. The reaction was accomplished at room temperature to afford reasonable to good yields. Syntheses and characterization of three diphenyl phosphate based. Cu(II) complexes ...

  15. Transition metal chemistry of hydroxy(–OH)-rich molecules ...

    Indian Academy of Sciences (India)

    Administrator

    Appropriately designed hydroxy(–OH) containing Schiff's base and Mannich base molecules have been recently found to be important for development of the coordination chemistry of a number of metal ions in the biomimetic chemistry of metalloenzymes. In this context, our group has studied the coordination role of these ...

  16. Utilizing the phenol byproducts of coke production: 3. Phenols as coinhibitors of thermopolymerization during styrene production

    Energy Technology Data Exchange (ETDEWEB)

    I.I. Batura; A.F. Gogotov; V.I. Cherepanov; O.I. Baranov; A.A. Levchuk; M.V. Parilova [Irkutsk State Technical University, Irkutsk (Russian Federation)

    2009-01-15

    A new oligomerization procedure for phenol byproducts from coke production is experimentally studied. This method, oxidative combination, is intended to produce an effective coinhibitor of styrene thermopolymerization. When combined with a Mannich base, the new oligomer exhibits excellent inhibiting properties in the heat treatment of styrene and matches the effectiveness of imported inhibitors based on nitroxyl radicals. 15 refs., 1 tab.

  17. Journal of Chemical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 112; Issue 6. Exogenous bridging and nonbridging in Cu(II) complexes of Mannich base ligands: Synthesis and physical properties. S Sujatha T M Rajendiran R Kannappan R Venkatesan P Sambasiva Rao. Inorganic and Analytical Volume 112 Issue 6 December ...

  18. JCSC_128_12_1855_1860_SI.doc

    Indian Academy of Sciences (India)

    Choline-based biodegradable ionic liquid catalyst for Mannich-type reaction. PENG HUANa, HU YULINb, XING RONGa, b and FANG DONG*,a, b. a College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, P.R. China. bSchool of Chemistry & Environmental Engineering, Yancheng Teachers University, ...

  19. Review

    African Journals Online (AJOL)

    2016-01-01

    Jan 1, 2016 ... A new Mannich base 2-(morpholin-4-ylmethyl)isoindole-1,3-dione 30 and its coordination complexes with manganese(II) and cobalt(II) ions (Scheme 28) have been synthesized and characterized by Ramesh & Sabastiyan [33]. The structural features of the complexes were investigated by elemental ...

  20. Journal of Chemical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Exogenous bridging and nonbridging in Cu(II) complexes of Mannich base ligands: Synthesis and physical properties · S Sujatha T M Rajendiran ... Inorganic and Analytical. Coenzyme B12 model studies: An HSAB approach to the equilibria and kinetics of axial ligation of alkyl(aquo)-cobaloximes by imidazole and cyanide.

  1. Ayeni and Egharevba (14).cdr

    African Journals Online (AJOL)

    Timothy Ademakinwa

    INTRODUCTION. Studies of Mannich base complexes have grown over the years due to the selectivity and sensitivity of the ligands to various metal ions. Several media have been reported to operate for the reaction including acidic, basic and neutral media (Syamala,. 2009).In practice, phenols can serve as substrate.

  2. 4,4´-Diiodo-2,2´[(3aR,7aR )-2,3,3a,4,5,6,7,7a-octahydro-1H-1,3-benzimidazole-1,3-diyl)bis(methylene)]diphenol

    Czech Academy of Sciences Publication Activity Database

    Rivera, A.; Quiroga, D.; Ríos-Motta, J.; Fejfarová, Karla; Dušek, Michal

    2011-01-01

    Roč. 67, Part 9 (2011), o2256-u1932 ISSN 1600-5368 R&D Projects: GA ČR(CZ) GAP204/11/0809 Institutional research plan: CEZ:AV0Z10100521 Keywords : Mannich bases * crystal structure * X-ray diffraction Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.347, year: 2011

  3. Synthesis, biological evaluation and molecular docking studies of ...

    African Journals Online (AJOL)

    Compound 4, i.e., 1,3,4-oxadiazole-2-thione and its corresponding Mannich bases (5-17) were subjected to in silico screening as urease inhibitors, using crystal structure of urease (Protein Data Bank ID: 5FSE) as a model enzyme. Furthermore, the targeted compounds were evaluated for their in vitro urease inhibition and ...

  4. C Thangaraja

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences. C Thangaraja. Articles written in Journal of Chemical Sciences. Volume 116 Issue 4 June 2004 pp 209-213 Full Papers. A new Mannich base and its transition metal (II) complexes - Synthesis, structural characterization and electrochemical study · N Raman S Esthar C ...

  5. Journal of Chemical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Volume 112, Issue 6. December 2000, pages 559-642. pp 559-572 Inorganic and Analytical. Exogenous bridging and nonbridging in Cu(II) complexes of Mannich base ligands: Synthesis and physical properties · S Sujatha T M Rajendiran R Kannappan R Venkatesan P Sambasiva Rao · More Details Abstract Fulltext PDF.

  6. 4-Hydroxy-1-naphthaldehydes: proton transfer or deprotonation

    DEFF Research Database (Denmark)

    Manolova, Y; Kurteva, V; Antonov, L

    2015-01-01

    . For 4-hydroxy-3-(piperidin-1-ylmethyl)-1-naphthaldehyde (a Mannich base) an intramolecular proton transfer involving the OH group and the piperidine nitrogen occurs. In acetonitrile the equilibrium is predominantly at the OH-form, whereas in methanol the proton transferred tautomer is the preferred form...

  7. binuclear copper(II) complexes

    Indian Academy of Sciences (India)

    Administrator

    . ClO4·H2O of 'end-off' Mannich base ligands have been synthesized. Cyclic voltammetry of these complexes revealed that the reduction process involved two successive one- electron transfer steps at different potentials. CuIICuII → CuIICuI → ...

  8. Journal of Chemical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Synthesis, electrochemical and magnetic properties of new acylic 'end-off' binuclear copper(II) complexes · T M Rajendiran R Kannappan R Venkatesan P ... Exogenous bridging and nonbridging in Cu(II) complexes of Mannich base ligands: Synthesis and physical properties · S Sujatha T M Rajendiran R Kannappan R ...

  9. 77 FR 25235 - Significant New Use Rules on Certain Chemical Substances

    Science.gov (United States)

    2012-04-27

    ... PMN states that the generic (non- confidential) use of the substance will be as a reaction aid in.... CFR citation: 40 CFR 721.10300. PMN Number P-00-317 Chemical name: Reaction products of fatty alcohols... substance. CFR citation: 40 CFR 721.10317. PMN Numbers P-02-1078 and P-02-1080 Chemical names: Mannich bases...

  10. SYNTHESIS AND ANTIBACTERIAL EVALUATION OF SOME ...

    African Journals Online (AJOL)

    General procedure for the synthesis of Mannich Bases (III-V). Benzimidazolylthioacetic acid. (II) (0.002 mol) dissolved in ethanol and 3-4 drops of conc. HCl was added and reaction mixture was kept for stirring. To the stirring reaction mixture, formaldehyde (0.002 mol) was added drop wise and stirring was continued for 10 ...

  11. Synthesis of differently substituted tacn-based ligands. Towards the control of solubility and electronic and steric properties of uranium coordination complexes

    Energy Technology Data Exchange (ETDEWEB)

    Nizovtsev, Alexey V.; Scheurer, Andreas; Kosog, Boris; Heinemann, Frank W.; Meyer, Karsten [Department Chemie und Pharmazie, Lehrstuhl fuer Anorganische und Allgemeine Chemie, Universitaet Erlangen-Nuernberg, Erlangen (Germany)

    2013-05-15

    Starting from phenols {sup R1,R2}ArOH (5) and the anisole derivative 3,5-di-tert-butyl-2-methoxybenzyl bromide (13), a series of new tacn-based ligands ({sup R1,R2}ArOR{sup 3}){sub 3}tacn (2) have been synthesized with substituents of varying bulkiness and electronic nature at the ortho and para positions with respect to the oxygen coordination site. It was observed that these groups not only determine the steric shielding and solubility properties of 2, but also deactivate the reactivity of the phenols in the modified Mannich reaction when electron-withdrawing groups are introduced at the para position in 5. Treatment of the ligands with UCl{sub 4} in thf led to the isolation of four uranium(IV) chloro complexes [{("R"1","R"2ArO)_3tacn}U{sup IV}Cl] (14), which were characterized by different spectroscopic and physical methods (e.g., {sup 1}H NMR, UV/Vis, SQUID), corroborating the +4 oxidation state in 14. Single-crystal X-ray structure analyses revealed that 14a.CH{sub 2}Cl{sub 2}.CH{sub 3}CN and 14b.1.25CH{sub 2}Cl{sub 2} crystallize in the chiral, orthorhombic space group P2{sub 1}2{sub 1}2{sub 1} [a = 24.934(3), b = 27.941(3), c = 9.045(1) Aa, V = 6302(2) Aa{sup 3}, Z = 4] and the chiral, hexagonal space group P6{sub 3} [a = 22.097(3), c = 17.941(2) Aa, V = 7587(2) Aa{sup 3}, Z = 4], respectively. Interestingly, complexes 14a,b self-organize in the solid state into homochiral 1D polymeric superstructures as a result of weak intermolecular C-H..Cl contacts. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  12. New lab-made coagulant based on Schinopsis balansae tannin extract: synthesis optimization and preliminary tests on refractory water pollutants

    Science.gov (United States)

    Sánchez-Martín, J.; Beltrán-Heredia, J.; Coco-Rivero, B.

    2014-09-01

    Quebracho colorado tannin extract was used as a coagulant raw material for water and wastewater treatment. The chemical synthesis follows a Mannich reaction mechanism and provides a fully working coagulant that can remove several pollutants from water. This paper addresses the optimization of such synthesis and confirms the feasibility of the coagulant by testing it in a preliminary screening for the elimination of dyes and detergents. The optimum combination of reagents was 6.81 g of diethanolamine (DEA) and 2.78 g of formaldehyde (F) per g of tannin extract. So obtained coagulant was succesfully tested on the removal of 9 dyes and 8 detergents.

  13. Touch BASE

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    In a recent Nature article (see here), the BASE collaboration reported the most precise comparison of the charge-to-mass ratio of the proton to its antimatter equivalent, the antiproton. This result is just the beginning and many more challenges lie ahead.   CERN's AD Hall, where the BASE experiment is set-up. The Baryon Antibaryon Symmetry Experiment (BASE) was approved in June 2013 and was ready to take data in August 2014. During these 14 months, the BASE collaboration worked hard to set up its four cryogenic Penning traps, which are the heart of the whole experiment. As their name indicates, these magnetic devices are used to trap antiparticles – antiprotons coming from the Antiproton Decelerator – and particles of matter – negative hydrogen ions produced in the system by interaction with a degrader that slows the antiprotons down, allowing scientists to perform their measurements. “We had very little time to set up the wh...

  14. Synthesis of 6-Substituted-2,4-Diamino-5,6,7,8-Tetrahydropyrimido(4-5-d)Pyrimidines.

    Science.gov (United States)

    1979-10-01

    formaldehyde, pH changes with acid or base catalysis . The corresponding methylene bis anilines were prepared, accord- ing to the method of Bischoff and...acid or base catalysis resulted in cleavage to produce 4-chlorophenol. The instability of this compound under conditions necessary for Mannich reaction...5 mmole) was treated with a solution of 2,4,6-triaminopyrimidine (0.625 g, 5 nunole) in 30 ml Etanol and the resulting solution was heated under

  15. Cu-catalyzed cross-dehydrogenative coupling: A versatile strategy for C-C bond formations via the oxidative activation of sp3 C-H bonds

    Science.gov (United States)

    Li, Zhiping; Bohle, D. Scott; Li, Chao-Jun

    2006-06-01

    Cu-catalyzed cross-dehydrogenative coupling (CDC) methodologies were developed based on the oxidative activation of sp3 C-H bonds adjacent to a nitrogen atom. Various sp, sp2, and sp3 C-H bonds of pronucleophiles were used in the Cu-catalyzed CDC reactions. Based on these results, the mechanisms of the CDC reactions also are discussed. C-H activation | catalysis | Baylis-Hillman reaction | Mannich reaction | Friedel-Crafts reaction

  16. Web based foundry knowledge base

    Directory of Open Access Journals (Sweden)

    A. Stawowy

    2009-01-01

    Full Text Available The main assumptions and functions of proposed Foundry Knowledge Base (FKB are presented in this paper. FKB is a framework forinformation exchange of casting products and manufacturing methods. We use CMS (Content Management System to develope andmaintain our web-based system. The CastML – XML dialect developed by authors for description of casting products and processes – isused as a tool for information interchange between ours and outside systems, while SQL is used to store and edit knowledge rules and alsoto solve the basic selection problems in the rule-based module. Besides the standard functions (companies data, news, events, forums and media kit, our website contains a number of nonstandard functions; the intelligent search module based on expert system is the main advantage of our solution. FKB is to be a social portal which content will be developed by foundry community.

  17. Di-n-butyl 4,4´-dihydroxy-3,3´-{[(3aRS,7aRS )-2,3,3a,4,5,6,7,7a-octahydro-1H -1,3-benzimidazole-1,3-diyl]bis(methylene)}dibenzoate

    Czech Academy of Sciences Publication Activity Database

    Rivera, A.; Quiroga, D.; Ríos-Motta, J.; Fejfarová, Karla; Dušek, Michal

    2011-01-01

    Roč. 67, Part 9 (2011), o2297-u2304 ISSN 1600-5368 Grant - others:AV ČR(CZ) AP0701 Program:Akademická prémie - Praemium Academiae Institutional research plan: CEZ:AV0Z10100521 Keywords : Mannich bases * crystal structure * X-ray diffraction Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.347, year: 2011

  18. Kinetic evidence of an apparent negative activation enthalpy in an organocatalytic process

    KAUST Repository

    Han, Xiao

    2013-08-30

    A combined kinetic and computational study on our tryptophan-based bifunctional thiourea catalyzed asymmetric Mannich reactions reveals an apparent negative activation enthalpy. The formation of the pre-transition state complex has been unambiguously confirmed and these observations provide an experimental support for the formation of multiple hydrogen bonding network between the substrates and the catalyst. Such interactions allow the creation of a binding cavity, a key factor to install high enantioselectivity.

  19. Asymmetric Formation of Bridged Benzoxazocines through an Organocatalytic Multicomponent Dienamine-Mediated One-Pot Cascade

    DEFF Research Database (Denmark)

    Ransborg, Lars Krogager; Overgaard, Mette Kiilerich; Hejmanowska, Joanna

    2014-01-01

    An organocatalytic one-pot cascade leading to the stereoselective formation of novel bridged benzoxazocines is presented. The developed methodology is based on the first example of a γ-selective-Mannich-initiated cascade reaction and allows for direct annulation of the bridged benzoxazocines...... by incorporation of various α,β-unsaturated aldehydes, electron-rich anilines, and electron-deficient salicylaldehydes. The synthetic applicability of the products is demonstrated by relevant transformations....

  20. 2,2'-[1,3-Diazinane-1,3-diylbis(methylene)]bis(4-bromophenol)

    Czech Academy of Sciences Publication Activity Database

    Rivera, A.; Trujillo, G.P.; Ríos-Motta, J.; Fejfarová, Karla; Dušek, Michal

    2012-01-01

    Roč. 68, č. 2 (2012), "O498"-"U1493" ISSN 1600-5368 Grant - others:AV ČR(CZ) AP0701 Program:Akademická prémie - Praemium Academiae Institutional research plan: CEZ:AV0Z10100521 Keywords : Mannich bases * crystal structure * X-ray diffraction * Jana2006 Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.347, year: 2011

  1. Dimethyl 4,4´-dihydroxy-3,3´-{[(3aRS,7aRS )-2,3,3a,4,5,6,7,7a-octahydro-1H-1,3-benzimidazole-1,3-diyl] bis(methylene)}dibenzoate

    Czech Academy of Sciences Publication Activity Database

    Rivera, A.; Quiroga, D.; Ríos-Motta, J.; Fejfarová, Karla; Dušek, Michal

    2011-01-01

    Roč. 67, Part 11 (2011), o2911-U276 ISSN 1600-5368 Grant - others:AV ČR(CZ) AP0701 Program:Akademická prémie - Praemium Academiae Institutional research plan: CEZ:AV0Z10100521 Keywords : Mannich bases * crystal structure * X-ray diffraction * Jana2006 Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.347, year: 2011

  2. 4,4´-Dimethoxy-2,2´-{[(3aRS,7aRS)-2,3,3a,4,5,6,7,7a-octahydro-1H-1,3- benzimidazole-1,3-diyl]bis(methylene)}diphenol

    Czech Academy of Sciences Publication Activity Database

    Rivera, A.; Quiroga, D.; Ríos-Motta, J.; Fejfarová, Karla; Dušek, Michal

    2011-01-01

    Roč. 67, Part 9 (2011), o2298-u2316 ISSN 1600-5368 Grant - others:AV ČR(CZ) AP0701 Program:Akademická prémie - Praemium Academiae Institutional research plan: CEZ:AV0Z10100521 Keywords : Mannich bases * crystal structure * X-ray diffraction Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.347, year: 2011

  3. 6,6´-Dimethyl-2,2´-[1,3-diazinane-1,3-diylbis(methylene)]diphenol

    Czech Academy of Sciences Publication Activity Database

    Rivera, A.; González, D.M.; Ríos-Motta, J.; Fejfarová, Karla; Dušek, Michal

    2012-01-01

    Roč. 68, Part 3 (2012), "o698"-"sup6" ISSN 1600-5368 Grant - others:AV ČR(CZ) AP0701 Program:Akademická prémie - Praemium Academiae Institutional research plan: CEZ:AV0Z10100521 Keywords : crystal structure * X-ray diffraction * Jana2006 * hydrogen bonds * Mannich bases Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.347, year: 2011

  4. Kinetic Evidence of an Apparent Negative Activation Enthalpy in an Organocatalytic Process

    Science.gov (United States)

    Han, Xiao; Lee, Richmond; Chen, Tao; Luo, Jie; Lu, Yixin; Huang, Kuo-Wei

    2013-08-01

    A combined kinetic and computational study on our tryptophan-based bifunctional thiourea catalyzed asymmetric Mannich reactions reveals an apparent negative activation enthalpy. The formation of the pre-transition state complex has been unambiguously confirmed and these observations provide an experimental support for the formation of multiple hydrogen bonding network between the substrates and the catalyst. Such interactions allow the creation of a binding cavity, a key factor to install high enantioselectivity.

  5. Army Drug Development Program. Phase 1. Clinical Testing

    Science.gov (United States)

    1981-02-01

    previous studies of WR 194,965’HTPC^ (an antimalarial of the Mannich base class), the top tolerated single dose in man was...significant. O0NC1IJSION: rto adverse reaction to drug. BMI-MBB 114 INDIVI0IAL FJlIUlxn’ FINAL SUMMARY EXPKRIMfWT ND. 15: QDMriNUATION OF...Other laboratory abnormalities were minimal or inoonnistent and rot considered significant. ODNgjJSION: No .»Iverse reaction to drug

  6. Strategy for Stereoselective Metal-free α-Functionalization of 2-Azaaryl Acetates with N-Boc Imines.

    Science.gov (United States)

    Bastida, Iñaki; Segundo, Marcos San; López, Rosa; Palomo, Claudio

    2017-09-27

    We report the first diastereo- and enantioselective formal Mannich reaction of 2-pyridyl acetates which gives rise to α- and β-functionalized 2-substituted pyridines. Key for success is the previous azaarene N-oxide formation enabling α-carbon deprotonation by a mild bifunctional Brønsted base and subsequent reaction with N-Boc imines under almost perfect stereocontrol. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Modification of methyl O-propargyl-D-glucosides: model studies for the synthesis of alkynyl based functional polysaccharides.

    Science.gov (United States)

    Tankam, Pascal F; Mischnick, Petra; Hopf, Henning; Jones, Peter G

    2007-10-15

    Methyl 4,6-O-benzylidene-2,3-di-O-propargyl-alpha-D-glucoside (2) has been prepared and its structure determined, including its X-ray structural analysis. For comparison the structure of the corresponding allyl derivative has also been determined by X-ray crystallography. Glucoside 2 is a versatile starting material for numerous novel derivatives such as diols, a diester, a diacid, and a dialdehyde. Subjecting 2 to a Mannich reaction leads to a (bis)amine in excellent yields. The click reaction between 2 and benzyl azide furnishes a (bis)triazole as the main product. Deprotection of 2 furnishes a (bis)propargyl ether, which can be converted by the methodology developed for 2 to the corresponding (bis)acetylenes; click reaction with benzyl azide converts 2 into a (bis)triazole.

  8. Fragmentation based

    Directory of Open Access Journals (Sweden)

    Shashank Srivastava

    2014-01-01

    Gaining the understanding of mobile agent architecture and the security concerns, in this paper, we proposed a security protocol which addresses security with mitigated computational cost. The protocol is a combination of self decryption, co-operation and obfuscation technique. To circumvent the risk of malicious code execution in attacking environment, we have proposed fragmentation based encryption technique. Our encryption technique suits the general mobile agent size and provides hard and thorny obfuscation increasing attacker’s challenge on the same plane providing better performance with respect to computational cost as compared to existing AES encryption.

  9. Synthesis and evaluation of some novel derivatives of 2-propoxybenzylidene isonicotinohydrazide for their potential antimicrobial activity

    Directory of Open Access Journals (Sweden)

    Malhotra Manav

    2012-01-01

    Full Text Available A novel series of Mannich which contained isoniaside were prepared. First by the reaction of 2-propoxybenzaldehyde with isoniazid corresponding hydrazone (2a was obtained. After that, product 2a after mannich reaction of aminomethylation with formaldehyde and secondary give amines (2b-2k. The inhibitory potencies of the synthesized compounds were assayed in vitro against a panel of microorganisms and against A549 human lung adenocarcinoma cell line. Compounds 2c and 2k displayed moderate to potent antimicrobial activity against all the tested strains and they also exhibited significant cytotoxicity in a dose-dependent manner with an IC50 values ranging from 2.84 to 8.55 (μg and 0.007-0.030 (μM. The structures of newly synthesized compounds were evaluated by elemental and spectral (IR, 1HNMR, 13C-NMR methods. The result demonstrates the potential and importance of developing new mannich bases which would be effective against resistant microbial strain and they may be useful leads for anticancer drug development in the future.

  10. Foundation: Transforming data bases into knowledge bases

    Science.gov (United States)

    Purves, R. B.; Carnes, James R.; Cutts, Dannie E.

    1987-01-01

    One approach to transforming information stored in relational data bases into knowledge based representations and back again is described. This system, called Foundation, allows knowledge bases to take advantage of vast amounts of pre-existing data. A benefit of this approach is inspection, and even population, of data bases through an intelligent knowledge-based front-end.

  11. The physics data base

    International Nuclear Information System (INIS)

    Gault, F.D.

    1984-01-01

    The physics data base is introduced along with its associated data base management system. The emphasis is on data and their use and a classification of data and of data bases is developed to distinguish compilation organizations. The characteristics of these organizations are examined briefly and the long term consequences of the physics data base discussed. (orig.)

  12. Ultrasound-assisted synthesis of β-amino ketones via a Mannich reaction catalyzed by Fe3O4 magnetite nanoparticles as an efficient, recyclable and heterogeneous catalyst

    Directory of Open Access Journals (Sweden)

    Naghi Saadatjoo

    2017-02-01

    The present methodology offers several advantages, such as good yields, short reaction times and a recyclable catalyst with a very easy work up. In addition, the obtained results indicated that MNPs can be used as an effective and inexpensive catalyst for stereoselective synthesis of β-amino carbonyl by a one-pot three component condensation of aldehydes, ketones and amines.

  13. Asymmetric Synthesis of Substituted Tropinones using the Intramolecular Mannich Cyclization Reaction and Acyclic N-Sulfinyl β-Amino Ketone Ketals

    Science.gov (United States)

    Davis, Franklin A.; Theddu, Naresh; Gaspari, Paul M.

    2009-01-01

    Sulfinimine-derived, enantiopure N-sulfinyl β-amino ketone ketals on hydrolysis give dehydropyrrolidine ketones that on treatment with (Boc)2O/DMAP afford substituted tropinones in good yield. PMID:19278245

  14. Solid Base Catalysis

    CERN Document Server

    Ono, Yoshio

    2011-01-01

    The importance of solid base catalysts has come to be recognized for their environmentally benign qualities, and much significant progress has been made over the past two decades in catalytic materials and solid base-catalyzed reactions. The book is focused on the solid base. Because of the advantages over liquid bases, the use of solid base catalysts in organic synthesis is expanding. Solid bases are easier to dispose than liquid bases, separation and recovery of products, catalysts and solvents are less difficult, and they are non-corrosive. Furthermore, base-catalyzed reactions can be performed without using solvents and even in the gas phase, opening up more possibilities for discovering novel reaction systems. Using numerous examples, the present volume describes the remarkable role solid base catalysis can play, given the ever increasing worldwide importance of "green" chemistry. The reader will obtain an overall view of solid base catalysis and gain insight into the versatility of the reactions to whic...

  15. Mobile Inquiry Based Learning

    NARCIS (Netherlands)

    Specht, Marcus

    2012-01-01

    Specht, M. (2012, 8 November). Mobile Inquiry Based Learning. Presentation given at the Workshop "Mobile inquiry-based learning" at the Mobile Learning Day 2012 at the Fernuniversität Hagen, Hagen, Germany.

  16. VectorBase

    Data.gov (United States)

    U.S. Department of Health & Human Services — VectorBase is a Bioinformatics Resource Center for invertebrate vectors. It is one of four Bioinformatics Resource Centers funded by NIAID to provide web-based...

  17. Some Brief Notes on Theoretical and Experimental Investigations of Intramolecular Hydrogen Bonding

    Directory of Open Access Journals (Sweden)

    Lucjan Sobczyk

    2016-12-01

    Full Text Available A review of selected literature data related to intramolecular hydrogen bonding in ortho-hydroxyaryl Schiff bases, ortho-hydroxyaryl ketones, ortho-hydroxyaryl amides, proton sponges and ortho-hydroxyaryl Mannich bases is presented. The paper reports on the application of experimental spectroscopic measurements (IR and NMR and quantum-mechanical calculations for investigations of the proton transfer processes, the potential energy curves, tautomeric equilibrium, aromaticity etc. Finally, the equilibrium between the intra- and inter-molecular hydrogen bonds in amides is discussed.

  18. The ground based plan

    International Nuclear Information System (INIS)

    1989-01-01

    The paper presents a report of ''The Ground Based Plan'' of the United Kingdom Science and Engineering Research Council. The ground based plan is a plan for research in astronomy and planetary science by ground based techniques. The contents of the report contains a description of:- the scientific objectives and technical requirements (the basis for the Plan), the present organisation and funding for the ground based programme, the Plan, the main scientific features and the further objectives of the Plan. (U.K.)

  19. Stolen Base Physics

    Science.gov (United States)

    Kagan, David

    2013-01-01

    Few plays in baseball are as consistently close and exciting as the stolen base. While there are several studies of sprinting, the art of base stealing is much more nuanced. This article describes the motion of the base-stealing runner using a very basic kinematic model. The model will be compared to some data from a Major League game. The…

  20. The inhibitors of corrosion and hydrogen entry into carbon steel in the H{sub 2}S and CO{sub 2} media

    Energy Technology Data Exchange (ETDEWEB)

    Tsygankova, L. E.; Vigdorovich, V. I.; Mozharov, A.V. [Derzhavin State University 33, Internatsionalnaya St., Tambov, 392622 (Russian Federation)

    2004-07-01

    The efficiency of Mannich's Phenol Bases (MPB) as the universal inhibitors of carbonic-acid and hydrogen-sulphide corrosion and hydrogen entry into carbon steel (St3) has been studied. Two Mannich's Phenol Bases were used: MPB 9 and MPB 9-20. Second of them has 20 ethoxy groups in the molecule. The HCl solutions (0.005 - 0.1 mole/l) saturated with CO{sub 2} (1-2 atm) and H{sub 2}S (50 - 400 mg/l) separately and together have been used. Protective efficiency of the inhibitors increases with increasing inhibitor concentration (10-200 mg/l), medium acidity and in the presence of CO{sub 2} and H{sub 2}S. The effect of the inhibitors is high enough in the presence of the liquid hydrocarbon (decane) in the used HCl solutions (1:10) too. Depending on the conditions the inhibitors slow down the anodic process (0.005 - 0.01 M HCl) or both partial electrode reactions (0.1 M HCl). In the presence of H{sub 2}S and CO{sub 2} separately and together Mannich's Phenol Bases decrease hydrogen entry into the steel membrane both at the corrosion potential and in the conditions of the anodic and cathodic polarization. An analysis of the mechanism of the hydrogen entry retardation in the presence of the inhibitors has been made taking into account a rate determining stage of the hydrogen evolution reaction and the existence of two forms of the adsorbed hydrogen atoms: subsurface and raised above surface. (authors)

  1. Value-based pricing

    OpenAIRE

    Netseva-Porcheva Tatyana

    2010-01-01

    The main aim of the paper is to present the value-based pricing. Therefore, the comparison between two approaches of pricing is made - cost-based pricing and value-based pricing. The 'Price sensitively meter' is presented. The other topic of the paper is the perceived value - meaning of the perceived value, the components of perceived value, the determination of perceived value and the increasing of perceived value. In addition, the best company strategies in matrix 'value-cost' are outlined. .

  2. Soy-based polyols

    Science.gov (United States)

    Suppes, Galen; Lozada, Zueica; Lubguban, Arnold

    2013-06-25

    The invention provides processes for preparing soy-based oligomeric polyols or substituted oligomeric polyols, as well as urethane bioelasteromers comprising the oligomeric polyols or substituted oligomeric polyols.

  3. XML-BASED REPRESENTATION

    Energy Technology Data Exchange (ETDEWEB)

    R. KELSEY

    2001-02-01

    For focused applications with limited user and use application communities, XML can be the right choice for representation. It is easy to use, maintain, and extend and enjoys wide support in commercial and research sectors. When the knowledge and information to be represented is object-based and use of that knowledge and information is a high priority, then XML-based representation should be considered. This paper discusses some of the issues involved in using XML-based representation and presents an example application that successfully uses an XML-based representation.

  4. Imagery Data Base Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Imagery Data Base Facility supports AFRL and other government organizations by providing imagery interpretation and analysis to users for data selection, imagery...

  5. Synthetic Base Fluids

    Science.gov (United States)

    Brown, M.; Fotheringham, J. D.; Hoyes, T. J.; Mortier, R. M.; Orszulik, S. T.; Randles, S. J.; Stroud, P. M.

    The chemical nature and technology of the main synthetic lubricant base fluids is described, covering polyalphaolefins, alkylated aromatics, gas-to-liquid (GTL) base fluids, polybutenes, aliphatic diesters, polyolesters, polyalkylene glycols or PAGs and phosphate esters.Other synthetic lubricant base oils such as the silicones, borate esters, perfluoroethers and polyphenylene ethers are considered to have restricted applications due to either high cost or performance limitations and are not considered here.Each of the main synthetic base fluids is described for their chemical and physical properties, manufacture and production, their chemistry, key properties, applications and their implications when used in the environment.

  6. Strengths-based Learning

    DEFF Research Database (Denmark)

    Ledertoug, Mette Marie

    Strength-based learning - Children͛s Character Strengths as Means to their Learning Potential͛ is a Ph.D.-project aiming to create a strength-based mindset in school settings and at the same time introducing strength-based interventions as specific tools to improve both learning and well......-being. The Ph.D.-project in Strength-based learning took place in a Danish school with 750 pupils age 6-16 and a similar school was functioning as a control group. The presentation will focus on both the aware-explore-apply processes and the practical implications for the schools involved, and on measurable...

  7. Monitoring Knowledge Base (MKB)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Monitoring Knowledge Base (MKB) is a compilation of emissions measurement and monitoring techniques associated with air pollution control devices, industrial...

  8. Case-based reasoning

    CERN Document Server

    Kolodner, Janet

    1993-01-01

    Case-based reasoning is one of the fastest growing areas in the field of knowledge-based systems and this book, authored by a leader in the field, is the first comprehensive text on the subject. Case-based reasoning systems are systems that store information about situations in their memory. As new problems arise, similar situations are searched out to help solve these problems. Problems are understood and inferences are made by finding the closest cases in memory, comparing and contrasting the problem with those cases, making inferences based on those comparisons, and asking questions whe

  9. Cobalt (II, nickel (II, copper (II and zinc (II complexes of 1-(phenyl(phenylamino methylpyrrolidine-2,5-dione and 2-((phenylaminomethyl isoindoline-1,3-dione and their biological activity

    Directory of Open Access Journals (Sweden)

    D. Tamil Vendan

    2010-12-01

    Full Text Available The new Mannich bases 1-(phenyl(phenylaminomethylpyrrolidine-2,5-dione (SBA was synthesized from the condensation of succinimide, benzaldehyde and aniline. 2-((phenylaminomethylisoindoline-1,3-dione (PFA was derived from pthalimide, formaldehyde and aniline. The general formula of the Co (II, Ni (II, Cu (II and Zn (II chloro complexes, ML2X2 are reported. The ligands and the complexes have been characterized by various physical-chemical techniques such as elemental analysis, molar conductance, magnetic susceptibility measurements, infrared and electronic spectra. The spectral analysis to ascertain mode of bonding and overall geometry of the complexes revealed octahedral geometries.

  10. A new spin label for SH groups in proteins: the synthesis and some applications in labelling of albumin and erythrocyte membranes

    International Nuclear Information System (INIS)

    Sholle, V.D.; Rozantsev, E.G.; Pop, V.I.; Benga, G.

    1980-03-01

    The synthesis of the paramagnetic Mannich base 3-methylene-5-(piperidine-N-methyl)-4-oxo-2,2,6,6-tetramethyl-piperidine-1-oxyl (compound II) was reported. This compound, proved as a very good spin label for protein SH groups, was used in labelling of albumin and arythrocyte membranes. It has been found that compound II was strongly bound to albumin and gave a two-component spectrum in erythrocyte membranes, making the study of conformational changes of proteins possible. (author)

  11. Synthesis and antibacterial activity of some new 4-anilino-5-phenyl-4H-1,2,4-triazole-3-thiol derivatives

    Directory of Open Access Journals (Sweden)

    Abd El-Badih A.G. Ghattas

    2016-11-01

    Full Text Available 4-Anilino-5-phenyl-4H-1,2,4-triazole-3-thiol (1 reacted with formaldehyde and different amines to give Mannich bases 2a–i. Treatment of compound 1 with formaldehyde afforded the corresponding 2-hydroxymethyl derivative 3, which upon its reaction with thionyl chloride yielded the corresponding chloromethyl derivative 4. Treatment of compound 4 with some thiols gave the corresponding sulfides 5a–f. The ring closure reaction of chloromethyl derivative 4 with hydrazine hydrate, phenyl hydrazine, hydroxylamine, urea and thiourea afforded triazolo-, oxadiazolo- and triazinotriazoles 6–10, respectively.

  12. Transamidation and transamidation-reduction of N-benzyltyramine with DMF

    Directory of Open Access Journals (Sweden)

    Christian Díaz Oviedo

    2018-01-01

    Full Text Available Tyramine and N-benzyltyramine react with formaldehyde to form azacyclophanes by means of aromatic Mannich reactions and react with non-enolizable aldehydes to form the respective Schiff bases. In this paper we present the unexpected synthesis of N-formyl-N-benzyltyramine and N-methyl-N-benzyltyramine by means of transamidation and transamidation-reduction of N-benzyltyramine with N,N-dimethylformamide. A reaction mechanism involving formylation of N-benzyltiramine followed by a Leuckart-Wallach reduction is proposed for rationalising such transformation.

  13. Mechanical Properties of Adhesively Bonded Aluminum Structures Protected with Hydration Inhibitors,

    Science.gov (United States)

    1984-11-01

    results). APPENDIX B: SYNTHESIS PHOSPHONATION (General) The preparation of a-aminomethylphosphonic acids involves a Mannich - type reaction based on the...TETRAMETHYLENE PHOSPHONIC ACID (EDTMP) REACTION *. .’-: -.. - 4 H2C 0 -- H)N2 3 0 (H20 3PCH 2)2NCH2)2NCH2P 3 22 :--:-: -- 44...18 hr) at 70°C. The reaction was terminated only when the 31P NMR spectrum of the contents indicated no further increase in the phosphonate peak

  14. Synthesis of new indolecarboxylic acids related to the plant hormone indoleacetic acid IAA

    Directory of Open Access Journals (Sweden)

    Rosa Flávia A. F. da

    2003-01-01

    Full Text Available The synthesis of 5,6-methylenedioxy-indol-3-yl-methanoic acid 8 and 5,6-methylenedioxy-indol-3-yl-acetic acid 13 is described. Piperonal was employed as starting material, and the construction of the heterocyclic ring based on the Hemetsberger reaction of the corresponding beta-azidostyrene was highly regiospecific. Compound 8 was obtained as a key intermediate towards 13, and a Mannich reaction was used to introduce the required alkyl side chain. The route comprised eight steps giving 13 in 26% overall yield. The formation of the indolic ring via reductive cyclisation of o,beta-dinitrostyrene is also presented.

  15. Secure base stations

    NARCIS (Netherlands)

    Bosch, Peter; Brusilovsky, Alec; McLellan, Rae; Mullender, Sape J.; Polakos, Paul

    2009-01-01

    With the introduction of the third generation (3G) Universal Mobile Telecommunications System (UMTS) base station router (BSR) and fourth generation (4G) base stations, such as the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) Evolved Node B (eNB), it has become important to

  16. Mutually unbiased bases

    Indian Academy of Sciences (India)

    Abstract. After a brief review of the notion of a full set of mutually unbiased bases in an N- dimensional Hilbert space, we summarize the work of Wootters and Fields (W K Wootters and. B C Fields, Ann. Phys. 191, 363 (1989)) which gives an explicit construction for such bases for the case N pr, where p is a prime. Further, we ...

  17. Game-Based Teaching

    DEFF Research Database (Denmark)

    Hanghøj, Thorkild

    2013-01-01

    This chapter outlines theoretical and empirical perspectives on how Game-Based Teaching can be integrated within the context of formal schooling. Initially, this is done by describing game scenarios as models for possible actions that need to be translated into curricular knowledge practices...... approaches to game-based teaching, which may or may not correspond with the pedagogical models of particular games....

  18. Home-based care

    African Journals Online (AJOL)

    Mrs. Patience Edoho Samson-Akpan

    PLWHA. The recommendation was that home based care should be encouraged and given priority by stake holders in the management of PLWHA. KEY WORDS: home-based care, quality of life, basic nursing care, psychosocial care. INTRODUCTION. HIV/AIDS is a chronic progressive disease which threatens the quality ...

  19. Diffusion Based Photon Mapping

    DEFF Research Database (Denmark)

    Schjøth, Lars; Olsen, Ole Fogh; Sporring, Jon

    2006-01-01

    . To address this problem we introduce a novel photon mapping algorithm based on nonlinear anisotropic diffusion. Our algorithm adapts according to the structure of the photon map such that smoothing occurs along edges and structures and not across. In this way we preserve the important illumination features......, while eliminating noise. We call our method diffusion based photon mapping....

  20. Skull base tumours

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Alexandra [Instituto Portugues de Oncologia Francisco Gentil, Servico de Radiologia, Rua Professor Lima Basto, 1093 Lisboa Codex (Portugal)], E-mail: borgesalexandra@clix.pt

    2008-06-15

    With the advances of cross-sectional imaging radiologists gained an increasing responsibility in the management of patients with skull base pathology. As this anatomic area is hidden to clinical exam, surgeons and radiation oncologists have to rely on imaging studies to plan the most adequate treatment. To fulfil these endeavour radiologists need to be knowledgeable about skull base anatomy, about the main treatment options available, their indications and contra-indications and needs to be aware of the wide gamut of pathologies seen in this anatomic region. This article will provide a radiologists' friendly approach to the central skull base and will review the most common central skull base tumours and tumours intrinsic to the bony skull base.

  1. Context Based Wikipedia Linking

    Science.gov (United States)

    Granitzer, Michael; Seifert, Christin; Zechner, Mario

    Automatically linking Wikipedia pages can be done either content based by exploiting word similarities or structure based by exploiting characteristics of the link graph. Our approach focuses on a content based strategy by detecting Wikipedia titles as link candidates and selecting the most relevant ones as links. The relevance calculation is based on the context, i.e. the surrounding text of a link candidate. Our goal was to evaluate the influence of the link-context on selecting relevant links and determining a links best-entry-point. Results show, that a whole Wikipedia page provides the best context for resolving link and that straight forward inverse document frequency based scoring of anchor texts achieves around 4% less Mean Average Precision on the provided data set.

  2. Evidence-based radiography

    International Nuclear Information System (INIS)

    Hafslund, Bjorg; Clare, Judith; Graverholt, Birgitte; Wammen Nortvedt, Monica

    2008-01-01

    Evidence-based practice (EBP) offers the integration of the best research evidence with clinical knowledge and expertise and patient values. EBP is a well known term in health care. This paper discusses the implementation of EBP into radiography and introduces the term evidence-based radiography. Evidence-based radiography is radiography informed and based on the combination of clinical expertise and the best available research-based evidence, patient preferences and resources available. In Norway, EBP in radiography is being debated and radiographers are discussing the challenges of implementing EBP in both academic and clinical practice. This discussion paper explains why EBP needs to be a basis for a radiography curriculum and a part of radiographers' practice. We argue that Norwegian radiographers must increase participation in research and developing practice within their specific radiographic domain

  3. QuickBase

    CERN Document Server

    Conner, Nancy

    2007-01-01

    Ready to put Intuit's QuickBase to work? Our new Missing Manual shows you how to capture, modify, share, and manage data and documents with this web-based data-sharing program quickly and easily. No longer do you have to coordinate your team through a blizzard of emails or play frustrating games of "guess which document is the right one."QuickBase saves your organization time and money, letting you manage and share the information that makes your business tick: sales figures, project timelines, drafts of documents, purchase or work requests--whatever information you need to keep business flowi

  4. Equipment fragility data base

    International Nuclear Information System (INIS)

    Cover, L.E.

    1982-03-01

    Part of the effort of the Seismic Safety Margins Research Program (SSMRP) has been directed at generating a fragility data base for equipment used in control and safety systems in commercial nuclear power plants. Component fragility data exist in various forms, depending on their content, intended use, and level of reduction. Th data are stored in a relational data base on the LLNL CDC 7600 computers; this provides easy accessibility for LLNL computer users. This report describes the present structure of the data base and presents its contents through the use of tables

  5. Value-based pricing

    Directory of Open Access Journals (Sweden)

    Netseva-Porcheva Tatyana

    2010-01-01

    Full Text Available The main aim of the paper is to present the value-based pricing. Therefore, the comparison between two approaches of pricing is made - cost-based pricing and value-based pricing. The 'Price sensitively meter' is presented. The other topic of the paper is the perceived value - meaning of the perceived value, the components of perceived value, the determination of perceived value and the increasing of perceived value. In addition, the best company strategies in matrix 'value-cost' are outlined. .

  6. Design-Based Research

    DEFF Research Database (Denmark)

    Gynther, Karsten; Christensen, Ove; Petersen, Trine Brun

    2012-01-01

    I denne artikel introduceres Design Based Research for første gang på dansk i et videnskabeligt tidsskrift. Artiklen præsenterer de grundlæggende antagelser, som ligger til grund for Design Based Research-traditionen, og artiklen diskuterer de principper, som ligger til grund for gennemførelse af...... et DBR-forskningsprojekt. Med udgangspunkt i forsknings- og udviklingsprojektet ELYK: E-læring, Yderområder og Klyngedannelse, præsenteres den innovationsmodel, som projektet har udviklet med udgangspunkt i Design Based Research traditionen. ELYKs DBR innovationsmodel har vist sig effektiv i forhold...

  7. Nature-based integration

    DEFF Research Database (Denmark)

    Pitkänen, Kati; Oratuomi, Joose; Hellgren, Daniela

    Increased attention to, and careful planning of the integration of migrants into Nordic societies is ever more important. Nature based integration is a new solution to respond to this need. This report presents the results of a Nordic survey and workshop and illustrates current practices of nature...... based integration by case study descriptions from Denmark, Sweden Norway and Finland. Across Nordic countries several practical projects and initiatives have been launched to promote the benefits of nature in integration and there is also growing academic interest in the topic. Nordic countries have...... the potential of becoming real forerunners in nature based integration even at the global scale....

  8. Cheboygan Vessel Base

    Data.gov (United States)

    Federal Laboratory Consortium — Cheboygan Vessel Base (CVB), located in Cheboygan, Michigan, is a field station of the USGS Great Lakes Science Center (GLSC). CVB was established by congressional...

  9. Biomimetics: nature based innovation

    National Research Council Canada - National Science Library

    Bar-Cohen, Yoseph

    2012-01-01

    "Based on the concept that nature offers numerous sources of inspiration for inventions related to mechanisms, materials, processes, and algorithms, this book covers the topic of biomimetics and the inspired innovation...

  10. Kelomehele preemia Baseli festivalil

    Index Scriptorium Estoniae

    2000-01-01

    Baselis festivalil "VIPER - International Festival for Film Video and New Media" tunnistati parimaks CD-ROMiks Gustav Deutschi/Anna Schimeki "Odysee today", netiprojektiks itaallaste "01.ORG", äramärkimispreemia - Raivo Kelomehe "Videoweaver"

  11. Hanscom Air Force Base

    Data.gov (United States)

    Federal Laboratory Consortium — MIT Lincoln Laboratory occupies 75 acres (20 acres of which are MIT property) on the eastern perimeter of Hanscom Air Force Base, which is at the nexus of Lexington,...

  12. Network-Based Effectiveness

    National Research Council Canada - National Science Library

    Friman, Henrik

    2006-01-01

    ... (extended from Leavitt, 1965). This text identifies aspects of network-based effectiveness that can benefit from a better understanding of leadership and management development of people, procedures, technology, and organizations...

  13. Evidence based practice

    DEFF Research Database (Denmark)

    Hjørland, Birger

    2011-01-01

    Evidence-based practice (EBP) is an influential interdisciplinary movement that originated in medicine as evidence-based medicine (EBM) about 1992. EBP is of considerable interest to library and information science (LIS) because it focuses on a thorough documentation of the basis for the decision...... making that is established in research as well as an optimization of every link in documentation and search processes. EBP is based on the philosophical doctrine of empiricism and, therefore, it is subject to the criticism that has been raised against empiricism. The main criticism of EBP...... is that practitioners lose their autonomy, that the understanding of theory and of underlying mechanisms is weakened, and that the concept of evidence is too narrow in the empiricist tradition. In this article, it is suggested that we should speak of “research-based practice” rather than EBP, because this term is open...

  14. WormBase

    Data.gov (United States)

    U.S. Department of Health & Human Services — WormBase is an international consortium of biologists and computer scientists dedicated to providing the research community with accurate, current, accessible...

  15. Loyalty Based Investment

    OpenAIRE

    Pei-Hsuan Lee; Ching-Wen Wang

    2010-01-01

    This study investigates the loyalty-based investment behavior in Taiwan. The link between team associations and loyalty has been examined to understand the characteristics of loyalty-based investors. The results revealed that both behavioral loyalty and attitudinal loyalty have significant positive effects on fans' investment intentions. Moreover, both attributes and benefits are significantly and positively related to either aspect of loyalty. In specific, behavioral loyalty has a higher inf...

  16. Game-based telerehabilitation.

    Science.gov (United States)

    Lange, B; Flynn, Sheryl M; Rizzo, A A

    2009-03-01

    This article summarizes the recent accomplishments and current challenges facing game-based virtual reality (VR) telerehabilitation. Specifically this article addresses accomplishments relative to realistic practice scenarios, part to whole practice, objective measurement of performance and progress, motivation, low cost, interaction devices and game design. Furthermore, a description of the current challenges facing game based telerehabilitation including the packaging, internet capabilities and access, data management, technical support, privacy protection, seizures, distance trials, scientific scrutiny and support from insurance companies.

  17. REST based mobile applications

    Science.gov (United States)

    Rambow, Mark; Preuss, Thomas; Berdux, Jörg; Conrad, Marc

    2008-02-01

    Simplicity is the major advantage of REST based webservices. Whereas SOAP is widespread in complex, security sensitive business-to-business aplications, REST is widely used for mashups and end-user centric applicatons. In that context we give an overview of REST and compare it to SOAP. Furthermore we apply the GeoDrawing application as an example for REST based mobile applications and emphasize on pros and cons for the use of REST in mobile application scenarios.

  18. Participatory design based research

    DEFF Research Database (Denmark)

    Dau, Susanne; Falk, Lars; Jensen, Louise Bach

    This poster reveal how participatory design based research by the use of a CoED inspired creative process can be used for designing solutions to problems regarding students study activities outside campus.......This poster reveal how participatory design based research by the use of a CoED inspired creative process can be used for designing solutions to problems regarding students study activities outside campus....

  19. Knowledge Based Strategy

    OpenAIRE

    Nicolescu, Ovidiu

    2006-01-01

    The paper is focused on the essential of knowledge-based strategy taking into consideration the theoretical and practical development during the last 10 years and especially knowledge revolution. It demonstrates the specificity of the company knowledgebased strategies and their necesity. More than this it presents essential elements regarding how to elaborate and to implement a knowledge based strategy starting from well know research in the field.

  20. Evidence-Based Development

    DEFF Research Database (Denmark)

    Hertzum, Morten; Simonsen, Jesper

    2004-01-01

    Systems development is replete with projects that represent substantial resource investments but result in systems that fail to meet users’ needs. Evidence-based development is an emerging idea intended to provide means for managing customer-vendor relationships and working systematically toward...... and electronic patient records for diabetes patients, this paper reports research in progress regarding the prospects and pitfalls of evidence-based development....

  1. [Endonasal skull base endoscopy].

    Science.gov (United States)

    Simal-Julián, Juan Antonio; Miranda-Lloret, Pablo; Pancucci, Giovanni; Evangelista-Zamora, Rocío; Pérez-Borredá, Pedro; Sanromán-Álvarez, Pablo; Perez-de-Sanromán, Laila; Botella-Asunción, Carlos

    2013-01-01

    The endoscopic endonasal techniques used in skull base surgery have evolved greatly in recent years. Our study objective was to perform a qualitative systematic review of the likewise systematic reviews in published English language literature, to examine the evidence and conclusions reached in these studies comparing transcranial and endoscopic approaches in skull base surgery. We searched the references on the MEDLINE and EMBASE electronic databases selecting the systematic reviews, meta-analyses and evidence based medicine reviews on skull based pathologies published from January 2000 until January 2013. We focused on endoscopic impact and on microsurgical and endoscopic technique comparisons. Full endoscopic endonasal approaches achieved gross total removal rates of craniopharyngiomas and chordomas higher than those for transcranial approaches. In anterior skull base meningiomas, complete resections were more frequently achieved after transcranial approaches, with a trend in favour of endoscopy with respect to visual prognosis. Endoscopic endonasal approaches minimised the postoperative complications after the treatment of cerebrospinal fluid (CSF) leaks, encephaloceles, meningoceles, craniopharyngiomas and chordomas, with the exception of postoperative CSF leaks. Randomized multicenter studies are necessary to resolve the controversy over endoscopic and microsurgical approaches in skull base surgery. Copyright © 2013 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

  2. LDEF materials data bases

    Science.gov (United States)

    Funk, Joan G.; Strickland, John W.; Davis, John M.

    1993-01-01

    The Long Duration Exposure Facility (LDEF) and the accompanying experiments were composed of and contained a wide variety of materials representing the largest collection of materials flown in low Earth orbit (LEO) and retrieved for ground based analysis to date. The results and implications of the mechanical, thermal, optical, and electrical data from these materials are the foundation on which future LEO space missions will be built. The LDEF Materials Special Investigation Group (MSIG) has been charged with establishing and developing data bases to document these materials and their performance to assure not only that the data are archived for future generations but also that the data are available to the spacecraft user community in an easily accessed, user-friendly form. This paper discusses the format and content of the three data bases developed or being developed to accomplish this task. The hardware and software requirements for each of these three data bases are discussed along with current availability of the data bases. This paper also serves as a user's guide to the MAPTIS LDEF Materials Data Base.

  3. Swarm-based medicine.

    Science.gov (United States)

    Putora, Paul Martin; Oldenburg, Jan

    2013-09-19

    Occasionally, medical decisions have to be taken in the absence of evidence-based guidelines. Other sources can be drawn upon to fill in the gaps, including experience and intuition. Authorities or experts, with their knowledge and experience, may provide further input--known as "eminence-based medicine". Due to the Internet and digital media, interactions among physicians now take place at a higher rate than ever before. With the rising number of interconnected individuals and their communication capabilities, the medical community is obtaining the properties of a swarm. The way individual physicians act depends on other physicians; medical societies act based on their members. Swarm behavior might facilitate the generation and distribution of knowledge as an unconscious process. As such, "swarm-based medicine" may add a further source of information to the classical approaches of evidence- and eminence-based medicine. How to integrate swarm-based medicine into practice is left to the individual physician, but even this decision will be influenced by the swarm.

  4. Paper based electronics platform

    KAUST Repository

    Nassar, Joanna Mohammad

    2017-07-20

    A flexible and non-functionalized low cost paper-based electronic system platform fabricated from common paper, such as paper based sensors, and methods of producing paper based sensors, and methods of sensing using the paper based sensors are provided. A method of producing a paper based sensor can include the steps of: a) providing a conventional paper product to serve as a substrate for the sensor or as an active material for the sensor or both, the paper product not further treated or functionalized; and b) applying a sensing element to the paper substrate, the sensing element selected from the group consisting of a conductive material, the conductive material providing contacts and interconnects, sensitive material film that exhibits sensitivity to pH levels, a compressible and/or porous material disposed between a pair of opposed conductive elements, or a combination of two of more said sensing elements. The method of sensing can further include measuring, using the sensing element, a change in resistance, a change in voltage, a change in current, a change in capacitance, or a combination of any two or more thereof.

  5. Cantilever Based Mass Sensing

    DEFF Research Database (Denmark)

    Dohn, Søren

    2007-01-01

    suitable for a portable device and to investigate the possibility of enhancing the functionality and sensitivity of cantilever based mass sensors. A readout method based on the hard contact between the cantilever and a biased electrode placed in close proximity to the cantilever is proposed. The viability...... the mass and position of a particle attached to a cantilever to the resonant frequency. It is shown theoretical possible to find the mass and position of a particle by measurements of the resonant frequency of several bending modes. In the measurements the sensitivity of the cantilever based mass sensor...... is improved when operated at higher bending modes. By measuring the resonant frequency of several bending modes both the mass and position of an attached gold bead are determined....

  6. Problem Based Learning

    DEFF Research Database (Denmark)

    de Graaff, Erik; Guerra, Aida

    Problem-Based Learning (PBL) is an innovative method to organize the learning process in such a way that the students actively engage in finding answers by themselves. During the past 40 years PBL has evolved and diversified resulting in a multitude in variations in models and practices. However......, the key principles remain the same everywhere. Graaff & Kolmos (2003) identify the main PBL principles as follows: 1. Problem orientation 2. Project organization through teams or group work 3. Participant-directed 4. Experiental learning 5. Activity-based learning 6. Interdisciplinary learning and 7...... in Engineering Education. In answer to the requests for visits the Aalborg Centre for Problem Based Learning in Engineering Science and Sustainability under the auspices of UNESCO (UCPBL) a two days programme for visitors is offered two times a year. The workshop is an introduction workshop to the Aalborg PBL...

  7. Location-based Scheduling

    DEFF Research Database (Denmark)

    Andersson, Niclas; Christensen, Knud

    the predominant scheduling method since it was introduced in the late 1950s. Over the years, CPM has proven to be a very powerful technique for planning, scheduling and controlling projects, which among other things is indicated by the development of a large number of CPM-based software applications available...... on the market. However, CPM is primarily an activity based method that takes the activity as the unit of focus and there is criticism raised, specifically in the case of construction projects, on the method for deficient management of construction work and continuous flow of resources. To seek solutions...... to the identified limitations of the CPM method, an alternative planning and scheduling methodology that includes locations is tested. Location-based Scheduling (LBS) implies a shift in focus, from primarily the activities to the flow of work through the various locations of the project, i.e. the building. LBS uses...

  8. Skull Base Anatomy.

    Science.gov (United States)

    Patel, Chirag R; Fernandez-Miranda, Juan C; Wang, Wei-Hsin; Wang, Eric W

    2016-02-01

    The anatomy of the skull base is complex with multiple neurovascular structures in a small space. Understanding all of the intricate relationships begins with understanding the anatomy of the sphenoid bone. The cavernous sinus contains the carotid artery and some of its branches; cranial nerves III, IV, VI, and V1; and transmits venous blood from multiple sources. The anterior skull base extends to the frontal sinus and is important to understand for sinus surgery and sinonasal malignancies. The clivus protects the brainstem and posterior cranial fossa. A thorough appreciation of the anatomy of these various areas allows for endoscopic endonasal approaches to the skull base. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Mutually unbiased unitary bases

    Science.gov (United States)

    Shaari, Jesni Shamsul; Nasir, Rinie N. M.; Mancini, Stefano

    2016-11-01

    We consider the notion of unitary transformations forming bases for subspaces of M (d ,C ) such that the square of the Hilbert-Schmidt inner product of matrices from the differing bases is a constant. Moving from the qubit case, we construct the maximal number of such bases for the four- and two-dimensional subspaces while proving the nonexistence of such a construction for the three-dimensional case. Extending this to higher dimensions, we commit to such a construct for the case of qutrits and provide evidence for the existence of such unitaries for prime dimensional quantum systems. Focusing on the qubit case, we show that the average fidelity for estimating any such transformation is equal to the case for estimating a completely unknown unitary from SU(2 ) . This is then followed by a quick application for such unitaries in a quantum cryptographic setup.

  10. Microwave Mediated Organic Reaction: A Convenient Approach for Rapid and Efficient Synthesis of Biologically Active Substituted 1,3-Dihydro-2H-indol-2-one Derivatives

    Directory of Open Access Journals (Sweden)

    Jnyanaranjan Panda

    2013-01-01

    Full Text Available A simple and efficient method has been developed for the synthesis of 1,3-dihydro-2H-indol-2-one derivatives using microwave irradiation technique. By taking advantage of the efficient source of energy of microwave, compound libraries for lead generation and optimization can be assembled in a fraction of time. In the present work, first the Schiff’s bases are synthesized by reaction of isatin with substituted anilines in the presence of acetic acid under microwave heating. Then the condensation of Schiff bases with different secondary amines in the presence of formaldehyde produces Mannich bases. The newly synthesized Mannich bases were characterized by means of spectral data and then evaluated for anthelmintic activity against Pheretima posthuma (Indian earthworm and compared with standard albendazole. The compounds were evaluated at the concentrations of 10, 20, and 50 mg/mL. The effect of the standard drug albendazole at 10 mg/mL was also evaluated. The results of the present study indicate that some of the test compounds significantly demonstrated paralysis and also caused death of worms in a dose-dependent manner.

  11. On multivariate Wilson bases

    DEFF Research Database (Denmark)

    Bownik, Marcin; Jakobsen, Mads Sielemann; Lemvig, Jakob

    2017-01-01

    A Wilson system is a collection of finite linear combinations of time frequency shifts of a square integrable function. In this paper we give an account of the construction of bimodular Wilson bases in higher dimensions from Gabor frames of redundancy two.......A Wilson system is a collection of finite linear combinations of time frequency shifts of a square integrable function. In this paper we give an account of the construction of bimodular Wilson bases in higher dimensions from Gabor frames of redundancy two....

  12. Inkjet-based micromanufacturing

    CERN Document Server

    Korvink, Jan G; Shin, Dong-Youn; Brand, Oliver; Fedder, Gary K; Hierold, Christofer; Tabata, Osamu

    2012-01-01

    Inkjet-based Micromanufacturing Inkjet technology goes way beyond putting ink on paper: it enables simpler, faster and more reliable manufacturing processes in the fields of micro- and nanotechnology. Modern inkjet heads are per se precision instruments that deposit droplets of fluids on a variety of surfaces in programmable, repeating patterns, allowing, after suitable modifications and adaptations, the manufacturing of devices such as thin-film transistors, polymer-based displays and photovoltaic elements. Moreover, inkjet technology facilitates the large-scale production of flexible RFID tr

  13. Scenario-based strategizing

    DEFF Research Database (Denmark)

    Lehr, Thomas; Lorenz, Ullrich; Willert, Markus

    2017-01-01

    on behavioural strategy as a theoretical lens, we design a yardstick to study the impact of scenario-based strategizing. We then describe our approach, which includes developing scenarios and alternative strategies separately and supporting the strategy selection through an integrated assessment of the goal......-based efficacy and robustness. To facilitate the colla- borative strategizing in teams, we propose a matrix with robustness and efficacy as the two axes, which we call the Parmenides Matrix. We assess the impact of the novel approach by applying it in two cases, at a govern- mental agency (German Environmental...... Ministry) and a firm affected by disruptive change (Bosch, leading global supplier of technology and solutions)....

  14. Iron-based superconductivity

    CERN Document Server

    Johnson, Peter D; Yin, Wei-Guo

    2015-01-01

    This volume presents an in-depth review of experimental and theoretical studies on the newly discovered Fe-based superconductors.  Following the Introduction, which places iron-based superconductors in the context of other unconventional superconductors, the book is divided into three sections covering sample growth, experimental characterization, and theoretical understanding.  To understand the complex structure-property relationships of these materials, results from a wide range of experimental techniques and theoretical approaches are described that probe the electronic and magnetic proper

  15. Identity-based encryption

    CERN Document Server

    Chatterjee, Sanjit

    2011-01-01

    Identity Based Encryption (IBE) is a type of public key encryption and has been intensely researched in the past decade. Identity-Based Encryption summarizes the available research for IBE and the main ideas that would enable users to pursue further work in this area. This book will also cover a brief background on Elliptic Curves and Pairings, security against chosen Cipher text Attacks, standards and more. Advanced-level students in computer science and mathematics who specialize in cryptology, and the general community of researchers in the area of cryptology and data security will find Ide

  16. Video-based rendering

    CERN Document Server

    Magnor, Marcus A

    2005-01-01

    Driven by consumer-market applications that enjoy steadily increasing economic importance, graphics hardware and rendering algorithms are a central focus of computer graphics research. Video-based rendering is an approach that aims to overcome the current bottleneck in the time-consuming modeling process and has applications in areas such as computer games, special effects, and interactive TV. This book offers an in-depth introduction to video-based rendering, a rapidly developing new interdisciplinary topic employing techniques from computer graphics, computer vision, and telecommunication en

  17. Evidence-Based Development

    DEFF Research Database (Denmark)

    Hertzum, Morten; Simonsen, Jesper

    2004-01-01

    Systems development is replete with projects that represent substantial resource investments but result in systems that fail to meet users’ needs. Evidence-based development is an emerging idea intended to provide means for managing customer-vendor relationships and working systematically toward...... meeting customer needs. We are suggesting that the effects of the use of a system should play a prominent role in the contractual definition of IT projects and that contract fulfilment should be determined on the basis of evidence of these effects. Based on two ongoing studies of home-care management...

  18. Scenario-based strategizing

    DEFF Research Database (Denmark)

    Lehr, Thomas; Lorenz, Ullrich; Willert, Markus

    2017-01-01

    For over 40 years, scenarios have been promoted as a key technique for forming strategies in uncertain en- vironments. However, many challenges remain. In this article, we discuss a novel approach designed to increase the applicability of scenario-based strategizing in top management teams. Drawing...... on behavioural strategy as a theoretical lens, we design a yardstick to study the impact of scenario-based strategizing. We then describe our approach, which includes developing scenarios and alternative strategies separately and supporting the strategy selection through an integrated assessment of the goal...... Ministry) and a firm affected by disruptive change (Bosch, leading global supplier of technology and solutions)....

  19. Molecule-based magnets

    Indian Academy of Sciences (India)

    The design of molecule-based magnets has also been extended to the design of poly-functional molecular magnets, such as those exhibiting second-order optical nonlinearity, liquid crystallinity, or chirality simultaneously with long-range magnetic order. Solubility, low density and biocompatibility are attractive features of ...

  20. Project-Based Science

    Science.gov (United States)

    Krajcik, Joe

    2015-01-01

    Project-based science is an exciting way to teach science that aligns with the "Next Generation Science Standards" ("NGSS"). By focusing on core ideas along with practices and crosscutting concepts, classrooms become learning environments where teachers and students engage in science by designing and carrying out…

  1. based gel polymer electrolytes

    Indian Academy of Sciences (India)

    Bull. Mater. Sci., Vol. 29, No. 7, December 2006, pp. 673–678. © Indian Academy of Sciences. 673. Investigation on poly (vinylidene fluoride) based gel polymer electrolytes ... (Alamgir and Abraham 1993; Sukeshini et al 1996; Ra- jendran and Uma ... Yang et al 1996; Ramesh and Arof 2001) and such elec- trolytes exhibit ...

  2. Wrought cobalt- base superalloys

    Science.gov (United States)

    Klarstrom, D. L.

    1993-08-01

    Wrought cobalt-base superalloys are used extensively in gas turbine engines because of their excellent high-temperature creep and fatigue strengths and resistance to hot corrosion attack. In addition, the unique character of the oxide scales that form on some of the alloys provides outstanding resistance to high-temperature sliding wear. This article provides a review of the evolutionary development of wrought cobalt-base alloys in terms of alloy design and physical metallurgy. The topics include solid-so-lution strengthening, carbide precipitation characteristics, and attempts to introduce age hardening. The use of PHACOMP to enhance thermal stability characteristics and the incorporation of rare-earth ele-ments to improve oxidation resistance is also reviewed and discussed. The further development of cobalt-base superalloys has been severely hampered by past political events, which have accentuated the strategic vulnerability of cobalt as a base or as an alloying element. Consequently, alternative alloys have been developed that use little or no cobalt. One such alternative, Haynes® 230TMalloy, is discussed briefly.

  3. Refractive index based measurements

    DEFF Research Database (Denmark)

    2014-01-01

    In a method for performing a refractive index based measurement of a property of a fluid such as chemical composition or temperature by observing an apparent angular shift in an interference fringe pattern produced by back or forward scattering interferometry, ambiguities in the measurement caused...

  4. Refractive index based measurements

    DEFF Research Database (Denmark)

    2014-01-01

    In a method for performing a refractive index based measurement of a property of a fluid such as chemical composition or temperature, a chirp in the local spatial frequency of interference fringes of an interference pattern is reduced by mathematical manipulation of the recorded light intensity...

  5. Refractive index based measurements

    DEFF Research Database (Denmark)

    2014-01-01

    A refractive index based measurement of a property of a fluid is measured in an apparatus comprising a variable wavelength coherent light source (16), a sample chamber (12), a wavelength controller (24), a light sensor (20), a data recorder (26) and a computation apparatus (28), by - directing...

  6. Community-Based Care

    Science.gov (United States)

    ... Health A to Z › Community-Based Care Font size A A A Print Share Glossary Basic Facts & Information Other Resources Caregiving How To's Tools & Tips Latest Research Getting More Help Related Topics Assisted Living Home Care Nursing Homes Join our e-newsletter! ...

  7. Mutually unbiased bases

    Indian Academy of Sciences (India)

    Mutually unbiased bases play an important role in quantum cryptography [2] and in the optimal determination of the density operator of an ensemble [3,4]. A density operator ρ in N-dimensions depends on N2 1 real quantities. With the help of MUB's, any such density operator can be encoded, in an optimal way, in terms of ...

  8. Lunar Base Sitting

    Science.gov (United States)

    Staehle, Robert L.; Burke, James D.; Snyder, Gerald C.; Dowling, Richard; Spudis, Paul D.

    1993-01-01

    Speculation with regard to a permanent lunar base has been with us since Robert Goddard was working on the first liquid-fueled rockets in the 1920's. With the infusion of data from the Apollo Moon flights, a once speculative area of space exploration has become an exciting possibility. A Moon base is not only a very real possibility, but is probably a critical element in the continuation of our piloted space program. This article, originally drafted by World Space Foundation volunteers in conjuction with various academic and research groups, examines some of the strategies involved in selecting an appropriate site for such a lunar base. Site selection involves a number of complex variables, including raw materials for possible rocket propellant generation, hot an cold cycles, view of the sky (for astronomical considerations, among others), geological makeup of the region, and more. This article summarizes the key base siting considerations and suggests some alternatives. Availability of specific resources, including energy and certain minerals, is critical to success.

  9. Problem-based learning

    NARCIS (Netherlands)

    Loyens, Sofie; Kirschner, Paul A.; Paas, Fred

    2010-01-01

    Loyens, S. M. M., Kirschner, P. A., & Paas, F. (2011). Problem-based learning. In S. Graham (Editor-in-Chief), A. Bus, S. Major, & L. Swanson (Associate Editors), APA educational psychology handbook: Vol. 3. Application to learning and teaching (pp. 403-425). Washington, DC: American Psychological

  10. ISFET based enzyme sensors

    NARCIS (Netherlands)

    van der Schoot, Bart H.; Bergveld, Piet

    1987-01-01

    This paper reviews the results that have been reported on ISFET based enzyme sensors. The most important improvement that results from the application of ISFETs instead of glass membrane electrodes is in the method of fabrication. Problems with regard to the pH dependence of the response and the

  11. Internet based benchmarking

    DEFF Research Database (Denmark)

    Bogetoft, Peter; Nielsen, Kurt

    2005-01-01

    We discuss the design of interactive, internet based benchmarking using parametric (statistical) as well as nonparametric (DEA) models. The user receives benchmarks and improvement potentials. The user is also given the possibility to search different efficiency frontiers and hereby to explore...

  12. Financing Competency Based Programs.

    Science.gov (United States)

    Daniel, Annette

    Literature on the background, causes, and current prevalence of competency based programs is synthesized in this report. According to one analysis of the actual and probable costs of minimum competency testing, estimated costs for test development, test administration, bureaucratic structures, and remedial programs for students who cannot pass the…

  13. Diffusion Based Photon Mapping

    DEFF Research Database (Denmark)

    Schjøth, Lars; Fogh Olsen, Ole; Sporring, Jon

    2007-01-01

    . To address this problem we introduce a novel photon mapping algorithm based on nonlinear anisotropic diffusion. Our algorithm adapts according to the structure of the photon map such that smoothing occurs along edges and structures and not across. In this way we preserve the important illumination features...

  14. Graphene-based spaser

    Science.gov (United States)

    Berman, Oleg; Kezerashvili, Roman; Lozovik, Yurii

    2013-03-01

    We propose graphene-based surface plasmon amplification by stimulated emission of radiation (spaser) formed in the graphene nanoribbon located near a semiconductor quantum dot (QD). The population inversion of the two electron levels of the QD can be achieved by applying external electric current or laser pumping. If the frequency of the dipole plasmon resonance in a graphene nanoribbon comes in the resonance with the transition frequency for the QD, it is possible to excite plasmons and generate the coherent surface plasmon states in the graphene nanoribbon. Therefore, the oscillating dipole in the QD excites coherent surface plasmons in the graphene nanoribbon. By solving the system of equations for the number of coherent localized plasmons in a graphene-based spaser the optimal design, optimal width of graphene nanoribbon and optimal regime for the graphene-based spaser are found. The minimal size and minimal threshold pumping intensity for the graphene-based spaser are obtained. The advantage of using graphene for the spaser is discussed.

  15. Molecule-based magnets

    Indian Academy of Sciences (India)

    Administrator

    Being weakly coloured, unlike their opaque classical magnet 'cousins' listed above, possibilities of ..... which confers a memory effect on it. Stronger coercive fields are expected for Co. 2+. -based molecular ... of them a colour change, too, occurs reversibly and simultaneously with the change in magnetic properties at.

  16. Fundamental research data base

    Science.gov (United States)

    1983-01-01

    A fundamental research data base containing ground truth, image, and Badhwar profile feature data for 17 North Dakota, South Dakota, and Minnesota agricultural sites is described. Image data was provided for a minimum of four acquisition dates for each site and all four images were registered to one another.

  17. Base tree property

    Czech Academy of Sciences Publication Activity Database

    Balcar, B.; Doucha, Michal; Hrušák, M.

    2015-01-01

    Roč. 32, č. 1 (2015), s. 69-81 ISSN 0167-8094 R&D Projects: GA AV ČR IAA100190902 Institutional support: RVO:67985840 Keywords : forcing * Boolean algebras * base tree Subject RIV: BA - General Mathematics Impact factor: 0.614, year: 2015 http://link.springer.com/article/10.1007/s11083-013-9316-2

  18. Steel column base classification

    OpenAIRE

    Jaspart, J.P.; Wald, F.; Weynand, K.; Gresnigt, A.M.

    2008-01-01

    The influence of the rotational characteristics of the column bases on the structural frame response is discussed and specific design criteria for stiffness classification into semi-rigid and rigid joints are derived. The particular case of an industrial portal frame is then considered. Peer reviewed

  19. Web Based VRML Modelling

    NARCIS (Netherlands)

    Kiss, S.; Sarfraz, M.

    2004-01-01

    Presents a method to connect VRML (Virtual Reality Modeling Language) and Java components in a Web page using EAI (External Authoring Interface), which makes it possible to interactively generate and edit VRML meshes. The meshes used are based on regular grids, to provide an interaction and modeling

  20. Web Based VRML Modelling

    NARCIS (Netherlands)

    Kiss, S.; Banissi, E.; Khosrowshahi, F.; Sarfraz, M.; Ursyn, A.

    2001-01-01

    Presents a method to connect VRML (Virtual Reality Modeling Language) and Java components in a Web page using EAI (External Authoring Interface), which makes it possible to interactively generate and edit VRML meshes. The meshes used are based on regular grids, to provide an interaction and modeling

  1. based gel polymer electrolytes

    Indian Academy of Sciences (India)

    operating systems. With this situation, attempts have been made in poly (ethylene oxide) (PEO) based polymer electrolytes to reach an appreciable electrical conducti- vity at ambient temperature (Wright 1975; Martuscelli et al 1984). Generally solid polymer electrolytes have many advantages, viz. high ionic conductivity, ...

  2. Dictionary Based Image Segmentation

    DEFF Research Database (Denmark)

    Dahl, Anders Bjorholm; Dahl, Vedrana Andersen

    2015-01-01

    We propose a method for weakly supervised segmentation of natural images, which may contain both textured or non-textured regions. Our texture representation is based on a dictionary of image patches. To divide an image into separated regions with similar texture we use an implicit level sets...

  3. Molecule-based magnets

    Indian Academy of Sciences (India)

    Administrator

    SmCo5, Nd2Fe14B etc are all atom-based, and their preparation/processing require high temperature routes. Employing ... synthesis of molecular magnets in 1986, a large variety of them have been synthesized, which can be catego- rized on the basis of the ..... magnetic behaviour of Fe[Fe(CN)6⋅xH2O nanoparticles.

  4. REST based service composition

    DEFF Research Database (Denmark)

    Grönvall, Erik; Ingstrup, Mads; Pløger, Morten

    2011-01-01

    This paper presents an ongoing work developing and testing a Service Composition framework based upon the REST architecture named SECREST. A minimalistic approach have been favored instead of a creating a complete infrastructure. One focus has been on the system's interaction model. Indeed, an ai...

  5. Zero-Base Budgeting.

    Science.gov (United States)

    Harvey, L. James

    The concept of Zero-Base Budgeting (ZBB) is discussed in terms of its application, advantages, disadvantages, and implementation in an effective planning, management, and evaluation (PME) system. A ZBB system requires administrators to: review all programs and expenditures annually, set clear cut goals, and analyze all possible alternatives for…

  6. Zero-Base Budgeting.

    Science.gov (United States)

    Yagielski, John

    In outline form, this document presents basic information on the school district, the reasons the district considered zero-base budgeting (ZBB), the formation and membership of the advisory School Cost Analysis Team, the district's investigation of the ZBB concept, an overview of the ways the district used the ZBB process, the identification of…

  7. Internet Based Benchmarking

    OpenAIRE

    Bogetoft, Peter; Nielsen, Kurt

    2002-01-01

    We discuss the design of interactive, internet based benchmarking using parametric (statistical) as well as non-parametric (DEA) models. The user receives benchmarks and improvement potentials. The user is also given the possibility to search different efficiency frontiers and hereby to explore alternative improvement strategies. An implementation of both a parametric and a non parametric model are presented.

  8. Mutually unbiased bases

    Indian Academy of Sciences (India)

    ... we show how, by exploiting certain freedom in the Wootters–Fields construction, the task of explicitly writing down such bases can be simplified for the case when is an odd prime. In particular, we express the results entirely in terms of the character vectors of the cyclic group of order . We also analyse the connection ...

  9. Surfel Based Geometry Resonstruction

    DEFF Research Database (Denmark)

    Andersen, Vedrana; Aanæs, Henrik; Bærentzen, Jakob Andreas

    2010-01-01

    We propose a method for retrieving a piecewise smooth surface from noisy data. In data acquired by a scanning process sampled points are almost never on the discontinuities making reconstruction of surfaces with sharp features difficult. Our method is based on a Markov Random Field (MRF) formulat...

  10. Performance based fault diagnosis

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    2002-01-01

    Different aspects of fault detection and fault isolation in closed-loop systems are considered. It is shown that using the standard setup known from feedback control, it is possible to formulate fault diagnosis problems based on a performance index in this general standard setup. It is also shown...

  11. Cotton-based nonwovens

    Science.gov (United States)

    This article is an abbreviated description of a new cotton-based nonwovens research program at the Southern Regional Research Center, which is one of the four regional research centers of the Agricultural Research Service, U.S. Department of Agriculture. Since cotton is a significant cash crop inte...

  12. Diffusion Based Photon Mapping

    DEFF Research Database (Denmark)

    Schjøth, Lars; Sporring, Jon; Fogh Olsen, Ole

    2008-01-01

    . To address this problem, we introduce a photon mapping algorithm based on nonlinear anisotropic diffusion. Our algorithm adapts according to the structure of the photon map such that smoothing occurs along edges and structures and not across. In this way, we preserve important illumination features, while...

  13. Spiritual-based Leadership

    DEFF Research Database (Denmark)

    Pruzan, Peter

    2015-01-01

    Although far from mainstream, the concept of spiritual-based leadership is emerging as an inclusive and yet highly personal approach to leadership that integrates a leader’s inner perspectives on identity, purpose, responsibility and success with her or his decisions and actions in the outer worl...

  14. Convolution based profile fitting

    International Nuclear Information System (INIS)

    Kern, A.; Coelho, A.A.; Cheary, R.W.

    2002-01-01

    Full text: In convolution based profile fitting, profiles are generated by convoluting functions together to form the observed profile shape. For a convolution of 'n' functions this process can be written as, Y(2θ)=F 1 (2θ)x F 2 (2θ)x... x F i (2θ)x....xF n (2θ). In powder diffractometry the functions F i (2θ) can be interpreted as the aberration functions of the diffractometer, but in general any combination of appropriate functions for F i (2θ) may be used in this context. Most direct convolution fitting methods are restricted to combinations of F i (2θ) that can be convoluted analytically (e.g. GSAS) such as Lorentzians, Gaussians, the hat (impulse) function and the exponential function. However, software such as TOPAS is now available that can accurately convolute and refine a wide variety of profile shapes numerically, including user defined profiles, without the need to convolute analytically. Some of the most important advantages of modern convolution based profile fitting are: 1) virtually any peak shape and angle dependence can normally be described using minimal profile parameters in laboratory and synchrotron X-ray data as well as in CW and TOF neutron data. This is possible because numerical convolution and numerical differentiation is used within the refinement procedure so that a wide range of functions can easily be incorporated into the convolution equation; 2) it can use physically based diffractometer models by convoluting the instrument aberration functions. This can be done for most laboratory based X-ray powder diffractometer configurations including conventional divergent beam instruments, parallel beam instruments, and diffractometers used for asymmetric diffraction. It can also accommodate various optical elements (e.g. multilayers and monochromators) and detector systems (e.g. point and position sensitive detectors) and has already been applied to neutron powder diffraction systems (e.g. ANSTO) as well as synchrotron based

  15. Spintronics-based computing

    CERN Document Server

    Prenat, Guillaume

    2015-01-01

    This book provides a comprehensive introduction to spintronics-based computing for the next generation of ultra-low power/highly reliable logic, which is widely considered a promising candidate to replace conventional, pure CMOS-based logic. It will cover aspects from device to system-level, including magnetic memory cells, device modeling, hybrid circuit structure, design methodology, CAD tools, and technological integration methods. This book is accessible to a variety of readers and little or no background in magnetism and spin electronics are required to understand its content.  The multidisciplinary team of expert authors from circuits, devices, computer architecture, CAD and system design reveal to readers the potential of spintronics nanodevices to reduce power consumption, improve reliability and enable new functionality.  .

  16. PACS Data Base Design

    Science.gov (United States)

    Zeleznik, Michael P.; Maguire, G. Q.; Baxter, B.

    1983-05-01

    A PACS database must manage three different types of data; structured data in the form of patient/exam identification information, and unstructured data in the form of text and images. Queries based on the content of text documents as well as the content of images must be suported, in addition to those based on standard, well structured keys such as name, age and sex. We model the PACS database as three logically distinct databases, each supporting one of these data types, with mapping structures relating all three. Several design issues which have a bearing, both on these models and on physical implemtations, are discussed. Because image database systems are the least understood at this time, most of the paper focusses on the them. We briefly discuss current trends in structured and text databases, without discussing commercial systems, and then present some current methods of implementing image database systems.

  17. Concrete lunar base investigation

    Science.gov (United States)

    Lin, T. D.; Senseny, Jonathan A.; Arp, Larry D.; Lindbergh, Charles

    1992-01-01

    This paper presents results of structural analyses and a preliminary design of a precast, prestressed concrete lunar base subjected to 1-atm internal pressure. The proposed infrastructure measures 120 ft in diameter and 72 ft in height, providing 33,000 sq ft of work area for scientific and industrial operations. Three loading conditions were considered in the design (1) during construction, (2) under pressurization, and (3) during an air-leak scenario. A floating foundation, capable of rigid body rotation and translation as the lunar soil beneath it yields, was developed to support the infrastructure and to ensure the airtightness of the system. Results reveal that it is feasible to use precast, prestressed concrete for construction of large lunar bases on the Moon.

  18. Technology based Education System

    DEFF Research Database (Denmark)

    Kant Hiran, Kamal; Doshi, Ruchi; Henten, Anders

    2016-01-01

    Abstract - Education plays a very important role for the development of the country. Education has multiple dimensions from schooling to higher education and research. In all these domains, there is invariably a need for technology based teaching and learning tools are highly demanded in the acad......Abstract - Education plays a very important role for the development of the country. Education has multiple dimensions from schooling to higher education and research. In all these domains, there is invariably a need for technology based teaching and learning tools are highly demanded...... and operational data that is used within a university for daily routine work. This paper presents a hybrid cloud computing model for higher education institutions to share intellectual data. Moreover, it proposes, the strategies for the implementation of the cloud computing in the academic institutions. Keywords...

  19. Animation-based Sketching

    DEFF Research Database (Denmark)

    Vistisen, Peter

    of contributions. In the produced work, I expand upon animation as a sketching approach to communicate, and explore interaction and user experience design concepts that are hard to grasp via traditional means of sketching. I propose that the sequential, temporal, material and narrative qualities of animation may...... experiments has been carried out, applying animation-based sketching in various contexts and at varying points in the design process. In the studies, I evaluate the viability of the approach, the practical integration into the design process, and map how consensus between stakeholders in design can...... be established through animation -based sketches. Thus, the scope of this project is practice-inclined, towards qualifying animation as an approach for design sketching in practice....

  20. Sparse approximation with bases

    CERN Document Server

    2015-01-01

    This book systematically presents recent fundamental results on greedy approximation with respect to bases. Motivated by numerous applications, the last decade has seen great successes in studying nonlinear sparse approximation. Recent findings have established that greedy-type algorithms are suitable methods of nonlinear approximation in both sparse approximation with respect to bases and sparse approximation with respect to redundant systems. These insights, combined with some previous fundamental results, form the basis for constructing the theory of greedy approximation. Taking into account the theoretical and practical demand for this kind of theory, the book systematically elaborates a theoretical framework for greedy approximation and its applications.  The book addresses the needs of researchers working in numerical mathematics, harmonic analysis, and functional analysis. It quickly takes the reader from classical results to the latest frontier, but is written at the level of a graduate course and do...

  1. Maintaining Relationship Based Procurement

    Directory of Open Access Journals (Sweden)

    Peter Davis

    2012-11-01

    Full Text Available Alliance and relationship projects are increasingin number and represent a large pool of work. Tobe successful relationship style contracts dependon soft-dollar factors, particularly the participants'ability to work together within an agreedframework, generally they are not based on lowbid tendering. Participants should be prepared todo business in an open environment based ontrust and mutually agreed governance. Theresearch evaluates relationship maintenance inthe implementation phase of constructionalliances - a particular derivative of relationshipstyle contracts. To determine the factors thatcontribute to relationship maintenance forty-nineexperienced Australian alliance projectmanagers were interviewed. The main findingswere; the development of relationships early inthe project form building blocks of success fromwhich relationships are maintained and projectvalue added; quality facilitation plays animportant part in relationship maintenance and ahybrid organisation created as a result of alliancedevelopment overcomes destructiveorganisational boundaries. Relationshipmaintenance is integral to alliance project controland failure to formalise it and pay attention toprocess and past outcomes will undermine analliance project's potential for success.

  2. Fusion safety data base

    International Nuclear Information System (INIS)

    Laats, E.T.; Hardy, H.A.

    1983-01-01

    The purpose of this Fusion Safety Data Base Program is to provide a repository of data for the design and development of safe commercial fusion reactors. The program is sponsored by the United States Department of Energy (DOE), Office of Fusion Energy. The function of the program is to collect, examine, permanently store, and make available the safety data to the entire US magnetic-fusion energy community. The sources of data will include domestic and foreign fusion reactor safety-related research programs. Any participant in the DOE Program may use the Data Base Program from his terminal through user friendly dialog and can view the contents in the form of text, tables, graphs, or system diagrams

  3. Conducting Polymer Based Nanobiosensors

    Directory of Open Access Journals (Sweden)

    Chul Soon Park

    2016-06-01

    Full Text Available In recent years, conducting polymer (CP nanomaterials have been used in a variety of fields, such as in energy, environmental, and biomedical applications, owing to their outstanding chemical and physical properties compared to conventional metal materials. In particular, nanobiosensors based on CP nanomaterials exhibit excellent performance sensing target molecules. The performance of CP nanobiosensors varies based on their size, shape, conductivity, and morphology, among other characteristics. Therefore, in this review, we provide an overview of the techniques commonly used to fabricate novel CP nanomaterials and their biosensor applications, including aptasensors, field-effect transistor (FET biosensors, human sense mimicking biosensors, and immunoassays. We also discuss prospects for state-of-the-art nanobiosensors using CP nanomaterials by focusing on strategies to overcome the current limitations.

  4. Knowledge based maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Sturm, A. [Hamburgische Electacitaets-Werke AG Hamburg (Germany)

    1997-12-31

    The establishment of maintenance strategies is of crucial significance for the reliability of a plant and the economic efficiency of maintenance measures. Knowledge about the condition of components and plants from the technical and business management point of view therefore becomes one of the fundamental questions and the key to efficient management and maintenance. A new way to determine the maintenance strategy can be called: Knowledge Based Maintenance. A simple method for determining strategies while taking the technical condition of the components of the production process into account to the greatest possible degree which can be shown. A software with an algorithm for Knowledge Based Maintenance leads the user during complex work to the determination of maintenance strategies for this complex plant components. (orig.)

  5. Arduino based laser control

    OpenAIRE

    Bernal Muñoz, Ferran

    2015-01-01

    ARDUINO is a vey usefull platform for prototypes. In this project ARDUINO will be used for controling a Semiconductor Tuneable Laser. [ANGLÈS] Diode laser for communications control based on an Arduino board. Temperature control implementation. Software and hardware protection for the laser implementation. [CASTELLÀ] Control de un láser de comunicaciones ópticas desde el ordenador utilizando una placa Arduino. Implementación de un control de temperatura y protección software y hardware ...

  6. Design bases - Concrete structures

    International Nuclear Information System (INIS)

    Diaz-Llanos Ros, M.

    1993-01-01

    The most suitable title for Section 2 is 'Design Bases', which covers not only calculation but also the following areas: - Structural design concepts. - Project criteria. - Material specifications. These concepts are developed in more detail in the following sections. The numbering in this document is neither complete nor hierarchical since, for easier cross referencing, it corresponds to the paragraphs of Eurocode 2 Part 1 (hereinafter 'EUR-2') which are commented on. (author)

  7. Boid Based Timetable Generation

    Science.gov (United States)

    Fulmański, Piotr

    2008-09-01

    The general timetabling problem consists of scheduling a number of events into a finite number of periods so that no individual entity is required to attend two or more events simultaneously. In most cases there will also be restrictions on the amount of resources, time etc. In this document we try to investigate a new method of timetable generation based not on popular evolutionary approach but on boids concept.

  8. Copper Pyrimidine based MOFs

    Indian Academy of Sciences (India)

    Cl..Cu.. interactions but restricted ..Cu..N N..Cu interacations. Supramolecular isomers of Br and I are reported for the first time in this paper. [Cu2I(pdz)X2]. Figure S18. Self assembly of the simultaneous presence of tecton {Cu(sol)3X} and {Cu(pdz)(sol)2X} result in [Cu2I(pdz)X2]. 1. Table S3. Copper Pyrimidine based MOFs ...

  9. Air Force Smart Bases

    Science.gov (United States)

    2017-10-19

    and mobility for generating combat power while maintaining cybersecurity and accruing the benefits of technology in their lives . Figure 2...Designers ideate 100’s if not 1000’s of ways IoT and smart base technologies may improve the lives of Airmen. Figure 3: A conceptual AF mobile...innovation that unlock mission capabilities for Airmen. Both use cases are important (and can be integrated), but the functionals must continue to remind

  10. Microbead agglutination based assays

    KAUST Repository

    Kodzius, Rimantas

    2013-01-21

    We report a simple and rapid room temperature assay for point-of-care (POC) testing that is based on specific agglutination. Agglutination tests are based on aggregation of microbeads in the presence of a specific analyte thus enabling the macroscopic observation. Such tests are most often used to explore antibody-antigen reactions. Agglutination has been used for protein assays using a biotin/streptavidin system as well as a hybridization based assay. The agglutination systems are prone to selftermination of the linking analyte, prone to active site saturation and loss of agglomeration at high analyte concentrations. We investigated the molecular target/ligand interaction, explaining the common agglutination problems related to analyte self-termination, linkage of the analyte to the same bead instead of different microbeads. We classified the agglutination process into three kinds of assays: a two- component assay, a three-component assay and a stepped three- component assay. Although we compared these three kinds of assays for recognizing DNA and protein molecules, the assay can be used for virtually any molecule, including ions and metabolites. In total, the optimized assay permits detecting analytes with high sensitivity in a short time, 5 min, at room temperature. Such a system is appropriate for POC testing.

  11. As bases do petismo

    Directory of Open Access Journals (Sweden)

    David Samuels

    2004-10-01

    Full Text Available A partir dos dados do ESEB de 2002 o autor realiza um estudo das bases eleitorais do PT e de hipóteses sobre a natureza do petismo. Através de técnicas estatísticas multivariadas, são testadas relações do petismo com variáveis demográficas, socioeconômicas e variáveis relativas a questões políticas específicas. Os resultados apontam que apenas a escolaridade tem uma associação específica com o petismo, com implicações para o seu comportamento sócio-político.Based on the results of the 2002 Brazilian Electoral Study, the author analyses the electoral bases of the Worker´s Party and the factors associated with the "petismo". The relationships between the "petismo"and the socioeconomic, demographic and political variables are tested using multivariate analysis. The results indicate that the only "social category"associated with "petismo"is level of education, and it has clear implications to their social and political behavior.

  12. Knowledge-based utility

    International Nuclear Information System (INIS)

    Chwalowski, M.

    1997-01-01

    This presentation provides industry examples of successful marketing practices by companies facing deregulation and competition. The common thread through the examples is that long term survival of today's utility structure is dependent on the strategic role of knowledge. As opposed to regulated monopolies which usually own huge physical assets and have very little intelligence about their customers, unregulated enterprises tend to be knowledge-based, characterized by higher market value than book value. A knowledge-based enterprise gathers data, creates information and develops knowledge by leveraging it as a competitive weapon. It institutionalizes human knowledge as a corporate asset for use over and over again by the use of databases, computer networks, patents, billing, collection and customer services (BCCS), branded interfaces and management capabilities. Activities to become knowledge-based such as replacing inventory/fixed assets with information about material usage to reduce expenditure and achieve more efficient operations, and by focusing on integration and value-adding delivery capabilities, were reviewed

  13. Evidence-based policy

    DEFF Research Database (Denmark)

    Vohnsen, Nina Holm

    2013-01-01

    A current ambition in welfare states as diverse as Denmark, the UK, and in the USA is to base political decision making on rigorous research (Cartwright et al 2009; Mulgan 2009; Bason 2010). Sound as this might seem the ambition has nevertheless been problematized by both policy-makers and the re......A current ambition in welfare states as diverse as Denmark, the UK, and in the USA is to base political decision making on rigorous research (Cartwright et al 2009; Mulgan 2009; Bason 2010). Sound as this might seem the ambition has nevertheless been problematized by both policy......-makers and the research community (e.g. Boden & Epstein 2006; House of Commons 2006; Cartwright et al 2009; Rod 2010; Vohnsen 2011). This article intends to draw out some general pitfalls in the curious meeting of science and politics by focusing on a particular attempt to make evidence-based legislation in Denmark (for...... a full account, see Vohnsen 2011). These insights will be relevant for the anthropological researcher of legislative processes who wishes to move beyond a merely discursive approach to the study of policy and politics....

  14. Nanoplatform-based molecular imaging

    National Research Council Canada - National Science Library

    Chen, Xiaoyuan

    2011-01-01

    "Nanoplathform-Based Molecular Imaging provides rationale for using nanoparticle-based probes for molecular imaging, then discusses general strategies for this underutilized, yet promising, technology...

  15. Comparison of sequence-based and structure-based phylogenetic ...

    Indian Academy of Sciences (India)

    Prakash

    Sequence-based and structure-based phylogeny. 85. J. Biosci. 32(1), January 2007 dispersion is independent of phylogenetic tree construction algorithms. 3. ... two groups only. 3.1 Families with high correlation between sequence- based and structure-based phylogenetic trees. There are 27 families with considerably high ...

  16. DOM Based XSS Detecting Method Based on Phantomjs

    Science.gov (United States)

    Dong, Ri-Zhan; Ling, Jie; Liu, Yi

    Because malicious code does not appear in html source code, DOM based XSS cannot be detected by traditional methods. By analyzing the causes of DOM based XSS, this paper proposes a detection method of DOM based XSS based on phantomjs. This paper uses function hijacking to detect dangerous operation and achieves a prototype system. Comparing with existing tools shows that the system improves the detection rate and the method is effective to detect DOM based XSS.

  17. Evidence-based guidelines

    DEFF Research Database (Denmark)

    Rovira, Àlex; Wattjes, Mike P; Tintoré, Mar

    2015-01-01

    The clinical use of MRI in patients with multiple sclerosis (MS) has advanced markedly over the past few years. Technical improvements and continuously emerging data from clinical trials and observational studies have contributed to the enhanced performance of this tool for achieving a prompt...... diagnosis in patients with MS. The aim of this article is to provide guidelines for the implementation of MRI of the brain and spinal cord in the diagnosis of patients who are suspected of having MS. These guidelines are based on an extensive review of the recent literature, as well as on the personal...... of MRI in clinical practice for the diagnosis of MS....

  18. Vision-based interaction

    CERN Document Server

    Turk, Matthew

    2013-01-01

    In its early years, the field of computer vision was largely motivated by researchers seeking computational models of biological vision and solutions to practical problems in manufacturing, defense, and medicine. For the past two decades or so, there has been an increasing interest in computer vision as an input modality in the context of human-computer interaction. Such vision-based interaction can endow interactive systems with visual capabilities similar to those important to human-human interaction, in order to perceive non-verbal cues and incorporate this information in applications such

  19. Polymerization Using Phosphazene Bases

    KAUST Repository

    Zhao, Junpeng

    2015-09-01

    In the recent rise of metal-free polymerization techniques, organic phosphazene superbases have shown their remarkable strength as promoter/catalyst for the anionic polymerization of various types of monomers. Generally, the complexation of phosphazene base with the counterion (proton or lithium cation) significantly improves the nucleophilicity of the initiator/chain end resulting in highly enhanced polymerization rates, as compared with conventional metalbased initiating systems. In this chapter, the general features of phosphazenepromoted/catalyzed polymerizations and the applications in macromolecular engineering (synthesis of functionalized polymers, block copolymers, and macromolecular architectures) are discussed with challenges and perspectives being pointed out.

  20. Oil based mud discharges

    International Nuclear Information System (INIS)

    Tiesma, R.

    1996-01-01

    The intensive use of oil based muds by the offshore oil and gas industry during the 1980s has caused considerable contamination around drilling sites. A recent investigation on the Norwegian continental shelf indicates that the situation is much worse than previously thought. This material suggests that oil pollution of this kind could be damaging the North Sea's endangered fish stocks, including cod, haddock and plaice. The amount of oil discharged in the UK sector is many times higher than in the other sectors, suggesting that the problem there may be even more serious. The amount discharged in the Dutch and Norwegian sectors are comparable. (author)

  1. Agent-Based Optimization

    CERN Document Server

    Jędrzejowicz, Piotr; Kacprzyk, Janusz

    2013-01-01

    This volume presents a collection of original research works by leading specialists focusing on novel and promising approaches in which the multi-agent system paradigm is used to support, enhance or replace traditional approaches to solving difficult optimization problems. The editors have invited several well-known specialists to present their solutions, tools, and models falling under the common denominator of the agent-based optimization. The book consists of eight chapters covering examples of application of the multi-agent paradigm and respective customized tools to solve  difficult optimization problems arising in different areas such as machine learning, scheduling, transportation and, more generally, distributed and cooperative problem solving.

  2. Teradata data base computer

    Energy Technology Data Exchange (ETDEWEB)

    1984-04-01

    To meet the growing demand for information management of large databases, Teradata Corporation has introduced the DBC/1012 data base computer, an IBM plug-compatible system that can handle data volumes up to a trillion bytes. Teradata estimates the DBC/1012 to be one-third the cost of an all-software relational system on a general purpose mainframe. Cost effectiveness, as well as fault tolerance, is achieved by a parallel architecture which processes data asynchronously using multiple independent microprocessors. Another cost saving results from the resources on the host mainframe that become available once the mainframe is relieved of the burden of maintaining the database.

  3. Problem Based Game Design

    DEFF Research Database (Denmark)

    Reng, Lars; Schoenau-Fog, Henrik

    2011-01-01

    At Aalborg University’s department of Medialogy, we are utilizing the Problem Based Learning method to encourage students to solve game design problems by pushing the boundaries and designing innovative games. This paper is concerned with describing this method, how students employ it in various...... projects and how they learn to analyse, design, and develop for innovation by using it. We will present various cases to exemplify the approach and focus on how the method engages students and aspires for innovation in digital entertainment and games....

  4. LIGHTWEIGHT CONCRETE BASED GRANSHLAK

    Directory of Open Access Journals (Sweden)

    NETESA M. I.

    2016-02-01

    Full Text Available Raising of problem. Concrete advisable to obtain a low strength with local secondary resources for recycling and reduce the environmental burden on the environment. But it is important to design such concrete compositions with a reduced flow of cement. It is known that the coefficient of efficiency of use of cement in the concrete of the heavy and B10 is less than about 0.5, which is almost two times smaller than in class B15 concrete and above. Even lower coefficient of efficiency in light concrete cement low strength. Therefore, it is important to find patterns determining the composition of lightweight concrete based on local-products industry with more efficient use of cement in them. Purpose.. Based on the analysis of earlier research results, including with the use of methods of mathematical planning of experiments to determine the concrete contents, which can provide the requirements for the underlying layers of the floor, the compressive strength of which should correspond to the class B5. It is important to provide the required strength at minimum flow of the cement, which is the most expensive and energy-intensive part of concrete. Conclusion. Analysis of the test results of control samples of concrete in 28-day-old, the following laws. The required tensile strength of concrete compressive strength of 7.0 MPa can be obtained in the test range when used in formulations as a filler as the Dnieper hydroelectric power station fly ash and tailings Krivoy Rog iron ore YuGOK. To ensure providing the required characteristic strength of the concrete in the underlying layers of the floor is advisable to use a nominal composition per cubic meter of concrete: cement 160 kg granshlaka Plant named after Petrovsky, 675 kg of fly ash Dnieper HPP 390 kg, 400 kg of sand, 230 liters of water. Thus, while ensuring rational grain composition components can obtain the desired strength lightweight concrete based granshlaka plant Petrovsky, using as fillers

  5. Web Based Customized Design

    OpenAIRE

    Moi, Morten Benestad

    2013-01-01

    This thesis studies the methods needed to create a web based application to remotely customize a CAD model. This includes customizing a CAD model by using a graphical user interface to be able to remotely control the inputs to- and outputs from the model in NX, and to get the result sent back to the user. Using CAD systems such as NX requires intensive training, is often a slow process and gives a lot of room for errors. An intuitive, simple user interface will eliminate the need for CAD trai...

  6. Sustainability Base Construction Update

    Science.gov (United States)

    Mewhinney, Michael

    2012-01-01

    Construction of the new Sustainability Base Collaborative support facility, expected to become the highest performing building in the federal government continues at NASA's Ames Research Center, Moffet Field, Calif. The new building is designed to achieve a platinum rating under the leadership in Energy and Environment Design (LEED) new construction standards for environmentally sustainable construction developed by the U. S. Green Building Council, Washington, D. C. When completed by the end of 2011, the $20.6 million building will feature near zero net energy consumption, use 90 percent less potable water than conventionally build buildings of equivalent size, and will result in reduced building maintenance costs.

  7. Cellular based cancer vaccines

    DEFF Research Database (Denmark)

    Hansen, M; Met, Ö; Svane, I M

    2012-01-01

    Cancer vaccines designed to re-calibrate the existing host-tumour interaction, tipping the balance from tumor acceptance towards tumor control holds huge potential to complement traditional cancer therapies. In general, limited success has been achieved with vaccines composed of tumor...... to transiently affect in vitro migration via autocrine receptor-mediated endocytosis of CCR7. In the current review, we discuss optimal design of DC maturation focused on pre-clinical as well as clinical results from standard and polarized dendritic cell based cancer vaccines....

  8. Pitch Based Sound Classification

    DEFF Research Database (Denmark)

    Nielsen, Andreas Brinch; Hansen, Lars Kai; Kjems, U

    2006-01-01

    A sound classification model is presented that can classify signals into music, noise and speech. The model extracts the pitch of the signal using the harmonic product spectrum. Based on the pitch estimate and a pitch error measure, features are created and used in a probabilistic model with soft......-max output function. Both linear and quadratic inputs are used. The model is trained on 2 hours of sound and tested on publicly available data. A test classification error below 0.05 with 1 s classification windows is achieved. Further more it is shown that linear input performs as well as a quadratic...

  9. Accelerator-based BNCT.

    Science.gov (United States)

    Kreiner, A J; Baldo, M; Bergueiro, J R; Cartelli, D; Castell, W; Thatar Vento, V; Gomez Asoia, J; Mercuri, D; Padulo, J; Suarez Sandin, J C; Erhardt, J; Kesque, J M; Valda, A A; Debray, M E; Somacal, H R; Igarzabal, M; Minsky, D M; Herrera, M S; Capoulat, M E; Gonzalez, S J; del Grosso, M F; Gagetti, L; Suarez Anzorena, M; Gun, M; Carranza, O

    2014-06-01

    The activity in accelerator development for accelerator-based BNCT (AB-BNCT) both worldwide and in Argentina is described. Projects in Russia, UK, Italy, Japan, Israel, and Argentina to develop AB-BNCT around different types of accelerators are briefly presented. In particular, the present status and recent progress of the Argentine project will be reviewed. The topics will cover: intense ion sources, accelerator tubes, transport of intense beams, beam diagnostics, the (9)Be(d,n) reaction as a possible neutron source, Beam Shaping Assemblies (BSA), a treatment room, and treatment planning in realistic cases. © 2013 Elsevier Ltd. All rights reserved.

  10. Situation based housing

    DEFF Research Database (Denmark)

    Duelund Mortensen, Peder; Welling, Helen; Wiell Nordberg, Lene

    2007-01-01

    of approaches to these goals. This working paper reviews not only a selection of new housing types, but also dwellings from the past, which each contain an aspect of changeability. Our study is based on information from users in the selected housing schemes, gathered from questionnaires, information about...... for living. The suitable condition consists of the dwelling's ability for physical displacement, spatial changes that can suit changing life styles. The situational condition is the not defined, the unfinished and the transitory, which continuously challenges the imagination and calls for the experiment. Our...

  11. Knowledge based Entrepreneurship

    DEFF Research Database (Denmark)

    Heebøll, John

    This book is dedicated enterprising people with a technical or a scientific background who consider commercializing ideas and inventions within their field of expertise via a new business activity or a new company. It aims at distilling experiences from many successful and not so successful start......-up ventures from the Technical University of Denmark, 1988 – 2008 into practical, portable knowledge that can be used by future knowledge-based entrepreneurs to set up new companies efficiently or to stay away from it; to do what’s needed and avoid the pitfalls....

  12. Problem Based Learning Online

    DEFF Research Database (Denmark)

    Kolbæk, Ditte

    2018-01-01

    “How do two online learning designs affect student engagement in the PBL online modules?” The empirical data were collected and analyzed using a netnographic approach. The study finds that concepts such as self-directed learning and active involvement may be perceived very differently from the students......Problem- and project- based learning (PBL) was originally developed for collaboration between physically present students and teachers, but political decisions at many universities also require that collaboration, dialogues, and other PBL activities take place online. Teachers design learning...

  13. Microlaser-based displays

    Science.gov (United States)

    Bergstedt, Robert; Fink, Charles G.; Flint, Graham W.; Hargis, David E.; Peppler, Philipp W.

    1997-07-01

    Laser Power Corporation has developed a new type of projection display, based upon microlaser technology and a novel scan architecture, which provides the foundation for bright, extremely high resolution images. A review of projection technologies is presented along with the limitations of each and the difficulties they experience in trying to generate high resolution imagery. The design of the microlaser based projector is discussed along with the advantage of this technology. High power red, green, and blue microlasers have been designed and developed specifically for use in projection displays. These sources, in combination with high resolution, high contrast modulator, produce a 24 bit color gamut, capable of supporting the full range of real world colors. The new scan architecture, which reduces the modulation rate and scan speeds required, is described. This scan architecture, along with the inherent brightness of the laser provides the fundamentals necessary to produce a 5120 by 4096 resolution display. The brightness and color uniformity of the display is excellent, allowing for tiling of the displays with far fewer artifacts than those in a traditionally tiled display. Applications for the display include simulators, command and control centers, and electronic cinema.

  14. SPACE BASED INTERCEPTOR SCALING

    Energy Technology Data Exchange (ETDEWEB)

    G. CANAVAN

    2001-02-01

    Space Based Interceptor (SBI) have ranges that are adequate to address rogue ICBMs. They are not overly sensitive to 30-60 s delay times. Current technologies would support boost phase intercept with about 150 interceptors. Higher acceleration and velocity could reduce than number by about a factor of 3 at the cost of heavier and more expensive Kinetic Kill Vehicles (KKVs). 6g SBI would reduce optimal constellation costs by about 35%; 8g SBI would reduce them another 20%. Interceptor ranges fall rapidly with theater missile range. Constellations increase significantly for ranges under 3,000 km, even with advanced interceptor technology. For distributed launches, these estimates recover earlier strategic scalings, which demonstrate the improved absentee ratio for larger or multiple launch areas. Constellations increase with the number of missiles and the number of interceptors launched at each. The economic estimates above suggest that two SBI per missile with a modest midcourse underlay is appropriate. The SBI KKV technology would appear to be common for space- and surface-based boost phase systems, and could have synergisms with improved midcourse intercept and discrimination systems. While advanced technology could be helpful in reducing costs, particularly for short range theater missiles, current technology appears adequate for pressing rogue ICBM, accidental, and unauthorized launches.

  15. Location-based games

    DEFF Research Database (Denmark)

    Ejsing-Duun, Stine

    In this dissertation, it is explored which prerequisites are necessary in location-based games (LBGs) to make meaningful the meeting between players and spatiality with an emphasis on physical locations. Throughout the dissertation, it has been shown that LBGs affect players’ perception of and be......In this dissertation, it is explored which prerequisites are necessary in location-based games (LBGs) to make meaningful the meeting between players and spatiality with an emphasis on physical locations. Throughout the dissertation, it has been shown that LBGs affect players’ perception...... of and behavior in everyday spaces, as the games reside on the boundaries between the continuums of play and ordinary, authentic and fictional, and as they merge physical and digital media. These are termed the six dimensions of LBGs. LBGs let the player explore the boundaries between these dimensions...... experiences of being in the world and the creation of meaning. The theory on motivation defines what motivation consists of and how it relates to our actions. This theory has been combined with theories concerning play and play culture, digital media, (digital) games, (optimal) experiences, landscape...

  16. DVD Based Electronic Pulser

    International Nuclear Information System (INIS)

    Morris, Scott J.; Pratt, Rick M.; Hughes, Michael A.; Kouzes, Richard T.; Pitts, W K.; Robinson, Eric E.

    2005-01-01

    This paper describes the design, construction, and testing of a DVD based electronic pulser system (DVDEPS). Such a device is used to generate pulse streams for simulation of both gamma and neutron detector systems. The DVDEPS reproduces a random pulse stream of a full HPGe spectrum as well as a digital pulse stream representing the output of a neutron multiplicity detector. The exchangeable DVD media contains over an hour of data for both detector systems and can contain an arbitrary gamma spectrum and neutron pulse stream. The data is written to the DVD using a desktop computer program from either actual or simulated spectra. The targeted use of the DVDEPS is authentication or validation of monitoring equipment for non-proliferation purposes, but it is also of general use whenever a complex data stream is required. The DVD based pulser combines the storage capacity and simplicity of DVD technology with commonly available electronic components to build a relatively inexpensive yet highly capable testing instrument

  17. Metasurface-Based Polarimeters

    Directory of Open Access Journals (Sweden)

    Fei Ding

    2018-04-01

    Full Text Available The state of polarization (SOP is an inherent property of light that can be used to gain crucial information about the composition and structure of materials interrogated with light. However, the SOP is difficult to experimentally determine since it involves phase information between orthogonal polarization states, and is uncorrelated with the light intensity and frequency, which can be easily determined with photodetectors and spectrometers. Rapid progress on optical gradient metasurfaces has resulted in the development of conceptually new approaches to the SOP characterization. In this paper, we review the fundamentals of and recent developments within metasurface-based polarimeters. Starting by introducing the concepts of generalized Snell’s law and Stokes parameters, we explain the Pancharatnam–Berry phase (PB-phase which is instrumental for differentiating between orthogonal circular polarizations. Then we review the recent progress in metasurface-based polarimeters, including polarimeters, spectropolarimeters, orbital angular momentum (OAM spectropolarimeters, and photodetector integrated polarimeters. The review is ended with a short conclusion and perspective for future developments.

  18. [Competence based medical education].

    Science.gov (United States)

    Bernabó, Jorge G; Buraschi, Jorge; Olcese, Juan; Buraschi, María; Duro, Eduardo

    2007-01-01

    The strategy of curriculum planning in the majority of the Schools of Medicine has shifted, in the past years, from curriculum models based in contents to outcome oriented curricula. Coincidently the interest in defining and evaluating the clinical competences that a graduate must have has grown. In our country, and particularly in the Associated Hospitals belonging to the Unidad Regional de Enseñanza IV of the UBA School of Medicine, evidence has been gathered showing that the acquisition of clinical competences during the grade is in general insufficient. The foundations and characteristics of PREM (Programa de Requisitos Esenciales Mínimos) are described. PREM is a tool to promote the apprenticeship of abilities and necessary skills for the practice of medicine. The objective of the program is to promote the apprenticeship of a well defined list of core competences considered indispensable for a general practitioner. An outcome oriented curriculum with a clear definition of the expected knowledge, skills and attitudes of a graduate of the programme, the promotion of learning experiences centered in the practice and evaluation tools based in direct observation of the student's performance should contribute to close the gap between what the Medicine Schools traditionally teach and evaluate, and what the doctor needs to know and needs to do to perform correctly its profession.

  19. Challenge Based Innovation gala

    CERN Multimedia

    CERN. Geneva; Utriainen, Tuuli Maria; Toivonen, Harri; Nordberg, Markus

    2014-01-01

    Challenge Based Innovation gala   There’s a new experiment starting in CERN called IdeaLab where we work together with detector R&D researchers to help them to bridge their knowledge into a more human, societally oriented context. Currently we are located in B153, but will move our activities to a new facility next to the Globe in May 2014. One of our first pilot projects is a 5 month course CBI (Challenge Based Innovation) where two multidisciplinary student teams join forces with Edusafe & TALENT projects at CERN. Their goal is to discover what kind of tools for learning could be created in collaboration with the two groups. After months of user interviews and low resolution prototyping they are ready to share the results with us in the form of an afternoon gala. We warmly welcome you to join us to see the students' results and experience the prototypes they have conceived. The event is in three parts, you are welcome to visit all of them,...

  20. Model Based Definition

    Science.gov (United States)

    Rowe, Sidney E.

    2010-01-01

    In September 2007, the Engineering Directorate at the Marshall Space Flight Center (MSFC) created the Design System Focus Team (DSFT). MSFC was responsible for the in-house design and development of the Ares 1 Upper Stage and the Engineering Directorate was preparing to deploy a new electronic Configuration Management and Data Management System with the Design Data Management System (DDMS) based upon a Commercial Off The Shelf (COTS) Product Data Management (PDM) System. The DSFT was to establish standardized CAD practices and a new data life cycle for design data. Of special interest here, the design teams were to implement Model Based Definition (MBD) in support of the Upper Stage manufacturing contract. It is noted that this MBD does use partially dimensioned drawings for auxiliary information to the model. The design data lifecycle implemented several new release states to be used prior to formal release that allowed the models to move through a flow of progressive maturity. The DSFT identified some 17 Lessons Learned as outcomes of the standards development, pathfinder deployments and initial application to the Upper Stage design completion. Some of the high value examples are reviewed.

  1. Constraint-based reachability

    Directory of Open Access Journals (Sweden)

    Arnaud Gotlieb

    2013-02-01

    Full Text Available Iterative imperative programs can be considered as infinite-state systems computing over possibly unbounded domains. Studying reachability in these systems is challenging as it requires to deal with an infinite number of states with standard backward or forward exploration strategies. An approach that we call Constraint-based reachability, is proposed to address reachability problems by exploring program states using a constraint model of the whole program. The keypoint of the approach is to interpret imperative constructions such as conditionals, loops, array and memory manipulations with the fundamental notion of constraint over a computational domain. By combining constraint filtering and abstraction techniques, Constraint-based reachability is able to solve reachability problems which are usually outside the scope of backward or forward exploration strategies. This paper proposes an interpretation of classical filtering consistencies used in Constraint Programming as abstract domain computations, and shows how this approach can be used to produce a constraint solver that efficiently generates solutions for reachability problems that are unsolvable by other approaches.

  2. Skull base tumor model.

    Science.gov (United States)

    Gragnaniello, Cristian; Nader, Remi; van Doormaal, Tristan; Kamel, Mahmoud; Voormolen, Eduard H J; Lasio, Giovanni; Aboud, Emad; Regli, Luca; Tulleken, Cornelius A F; Al-Mefty, Ossama

    2010-11-01

    Resident duty-hours restrictions have now been instituted in many countries worldwide. Shortened training times and increased public scrutiny of surgical competency have led to a move away from the traditional apprenticeship model of training. The development of educational models for brain anatomy is a fascinating innovation allowing neurosurgeons to train without the need to practice on real patients and it may be a solution to achieve competency within a shortened training period. The authors describe the use of Stratathane resin ST-504 polymer (SRSP), which is inserted at different intracranial locations to closely mimic meningiomas and other pathological entities of the skull base, in a cadaveric model, for use in neurosurgical training. Silicone-injected and pressurized cadaveric heads were used for studying the SRSP model. The SRSP presents unique intrinsic metamorphic characteristics: liquid at first, it expands and foams when injected into the desired area of the brain, forming a solid tumorlike structure. The authors injected SRSP via different passages that did not influence routes used for the surgical approach for resection of the simulated lesion. For example, SRSP injection routes included endonasal transsphenoidal or transoral approaches if lesions were to be removed through standard skull base approach, or, alternatively, SRSP was injected via a cranial approach if the removal was planned to be via the transsphenoidal or transoral route. The model was set in place in 3 countries (US, Italy, and The Netherlands), and a pool of 13 physicians from 4 different institutions (all surgeons and surgeons in training) participated in evaluating it and provided feedback. All 13 evaluating physicians had overall positive impressions of the model. The overall score on 9 components evaluated--including comparison between the tumor model and real tumor cases, perioperative requirements, general impression, and applicability--was 88% (100% being the best possible

  3. Space-Based Range

    Science.gov (United States)

    2008-01-01

    Space-Based Range (SBR), previously known as Space-Based Telemetry and Range Safety (STARS), is a multicenter NASA proof-of-concept project to determine if space-based communications using NASA's Tracking and Data Relay Satellite System (TDRSS) can support the Range Safety functions of acquiring tracking data and generating flight termination signals, while also providing broadband Range User data such as voice, video, and vehicle/payload data. There was a successful test of the Range Safety system at Wallops Flight Facility (WFF) on December 20, 2005, on a two-stage Terrier-Orion spin-stabilized sounding rocket. SBR transmitted GPS tracking data and maintained links with two TDRSS satellites simultaneously during the 10-min flight. The payload section deployed a parachute, landed in the Atlantic Ocean about 90 miles downrange from the launch site, and was successfully recovered. During the Terrier-Orion tests flights, more than 99 percent of all forward commands and more than 95 percent of all return frames were successfully received and processed. The time latency necessary for a command to travel from WFF over landlines to White Sands Complex and then to the vehicle via TDRSS, be processed onboard, and then be sent back to WFF was between 1.0 s and 1.1 s. The forward-link margins for TDRS-10 (TDRS East [TDE]) were 11 dB to 12 dB plus or minus 2 dB, and for TDRS-4 (TDRS Spare [TDS]) were 9 dB to 10 dB plus or minus 1.5 dB. The return-link margins for both TDE and TDS were 6 dB to 8 dB plus or minus 3 dB. There were 11 flights on an F-15B at Dryden Flight Research Center (DFRC) between November 2006 and February 2007. The Range User system tested a 184-element TDRSS Ku-band (15 GHz) phased-array antenna with data rates of 5 Mbps and 10 Mbps. This data was a combination of black-and-white cockpit video, Range Safety tracking and transceiver data, and aircraft and antenna controller data streams. IP data formatting was used.

  4. Touching base with OPERA

    CERN Multimedia

    CERN Bulletin

    2011-01-01

    Three seminars – at CERN, at Gran Sasso and in Japan – and an article calling for the scrutiny of the scientific community: the OPERA Collaboration opened its research publicly. In addition to huge press coverage, this triggered welcome reactions from colleagues around the world, many of whom will attempt to independently interpret and reproduce the measurement. OPERA’s Spokesperson touches base with the Bulletin.   The CERN Main Auditorium was crowded as OPERA Physics co-ordinator Dario Autiero presented the results of their research (23 September 2011). According to the OPERA strategy, the results of the measurements are in the hands of the scientific community and, as for any other scientific result, several months will be needed before other groups will be able to perform an independent measurement. In the meantime, the OPERA Collaboration is dealing with an avalanche of emails from the scientific community, members of the general public, and the press. &...

  5. Bases para proyectiles dirigidos

    Directory of Open Access Journals (Sweden)

    Editorial, Equipo

    1959-03-01

    Full Text Available Aunque actualmente no se ha llegado a una línea general de métodos o sistemas que gobiernen un tipo característico de rampa y servicios auxiliares necesarios para el lanzamiento al espacio de proyectiles dirigidos a grandes alturas y distancias, las experiencias obtenidas en diferentes ensayos, utilizando distintos tipos de proyectiles y trayectorias balísticas, han sentado toda una serie de procedimientos, datos y conclusiones de gran valor balístico que, aun teniendo en cuenta la continua evolución del proyectil, sus formas, combustibles y alcances, se conocen ya, con bastante aproximación, las condiciones mínimas que ha de reunir una base dedicada a este tipo de lanzamientos.

  6. Rate based failure detection

    Science.gov (United States)

    Johnson, Brett Emery Trabun; Gamage, Thoshitha Thanushka; Bakken, David Edward

    2018-01-02

    This disclosure describes, in part, a system management component and failure detection component for use in a power grid data network to identify anomalies within the network and systematically adjust the quality of service of data published by publishers and subscribed to by subscribers within the network. In one implementation, subscribers may identify a desired data rate, a minimum acceptable data rate, desired latency, minimum acceptable latency and a priority for each subscription. The failure detection component may identify an anomaly within the network and a source of the anomaly. Based on the identified anomaly, data rates and or data paths may be adjusted in real-time to ensure that the power grid data network does not become overloaded and/or fail.

  7. Behavior based safety

    International Nuclear Information System (INIS)

    Sudhikumaran, T.V.; Mehta, S.C.; Goyal, D.K.

    2009-01-01

    Behaviour Based Safety (popularly known as BBS) is a new methodology for achieving injury free work place and total Safety Culture. BBS is successfully being implemented and is being practiced as a work methodology for achieving a loss and injury free work environment and work practice. Through BBS, it was brought out that the root causes of all Industrial accidents some how originate from the 'at risk' behaviour of some individual or group of individuals at some level. The policy of NPCIL is to excel in the field of Industrial and Fire Safety in comparison to international standards. This article indents to bring out the various parameters helping in installing BBS programme at any plant. (author)

  8. Fuel cycle based safeguards

    International Nuclear Information System (INIS)

    De Montmollin, J.M.; Higinbotham, W.A.; Gupta, D.

    1985-07-01

    In NPT safeguards the same model approach and absolute-quantity inspection goals are applied at present to all similar facilities, irrespective of the State's fuel cycle. There is a continuing interest and activity on the part of the IAEA in new NPT safeguards approaches that more directly address a State's nuclear activities as a whole. This fuel cycle based safeguards system is expected to a) provide a statement of findings for the entire State rather than only for individual facilities; b) allocate inspection efforts so as to reflect more realistically the different categories of nuclear materials in the different parts of the fuel cycle and c) provide more timely and better coordinated information on the inputs, outputs and inventories of nuclear materials in a State. (orig./RF) [de

  9. Integrated data base program

    International Nuclear Information System (INIS)

    Notz, K.J.

    1981-01-01

    The IDB Program provides direct support to the DOE Nuclear Waste Management and Fuel Cycle Programs and their lead sites and support contractors by providing and maintaining a current, integrated data base of spent fuel and radioactive waste inventories and projections. All major waste types (HLW, TRU, and LLW) and sources (government, commerical fuel cycle, and I/I) are included. A major data compilation was issued in September, 1981: Spent Fuel and Radioactive Waste Inventories and Projections as of December 31, 1980, DOE/NE-0017. This report includes chapters on Spent Fuel, HLW, TRU Waste, LLW, Remedial Action Waste, Active Uranium Mill Tailings, and Airborne Waste, plus Appendices with more detailed data in selected areas such as isotopics, radioactivity, thermal power, projections, and land usage. The LLW sections include volumes, radioactivity, thermal power, current inventories, projected inventories and characteristics, source terms, land requirements, and a breakdown in terms of government/commercial and defense/fuel cycle/I and I

  10. Space-based detectors

    DEFF Research Database (Denmark)

    Sesana, A.; Weber, W. J.; Killow, C. J.

    2014-01-01

    ) is planned for 2015. This mission and its payload “LISA Technology Package” will demonstrate key technologies for LISA. In this context, reference masses in free fall for LISA, and gravitational physics in general, was described by William Weber, laser interferometry at the pico-metre level and the optical......The parallel session C5 on Space-Based Detectors gave a broad overview over the planned space missions related to gravitational wave detection. Overviews of the revolutionary science to be expected from LISA was given by Alberto Sesana and Sasha Buchman. The launch of LISA Pathfinder (LPF...... bench of LPF was presented by Christian Killow and the performance of the LPF optical metrology system by Paul McNamara. While LPF will not yet be sensitive to gravitational waves, it may nevertheless be used to explore fundamental physics questions, which was discussed by Michele Armano. Some parts...

  11. Base isolation: Fresh insight

    Energy Technology Data Exchange (ETDEWEB)

    Shustov, V.

    1993-07-15

    The objective of the research is a further development of the engineering concept of seismic isolation. Neglecting the transient stage of seismic loading results in a widespread misjudgement: The force of resistance associated with velocity is mostly conceived as a source of damping vibrations, though it is an active force at the same time, during an earthquake type excitation. For very pliant systems such as base isolated structures with relatively low bearing stiffness and with artificially added heavy damping mechanism, the so called `damping`` force may occur even the main pushing force at an earthquake. Thus, one of the two basic pillars of the common seismic isolation philosophy, namely, the doctrine of usefulness and necessity of a strong damping mechanism, is turning out to be a self-deception, sometimes even jeopardizing the safety of structures and discrediting the very idea of seismic isolation. There is a way out: breaking with damping dependancy.

  12. Transaction based approach

    Science.gov (United States)

    Hunka, Frantisek; Matula, Jiri

    2017-07-01

    Transaction based approach is utilized in some methodologies in business process modeling. Essential parts of these transactions are human beings. The notion of agent or actor role is usually used for them. The paper on a particular example describes possibilities of Design Engineering Methodology for Organizations (DEMO) and Resource-Event-Agent (REA) methodology. Whereas the DEMO methodology can be regarded as a generic methodology having its foundation in the theory of Enterprise Ontology the REA methodology is regarded as the domain specific methodology and has its origin in accountancy systems. The results of these approaches is that the DEMO methodology captures everything that happens in the reality with a good empirical evidence whereas the REA methodology captures only changes connected with economic events. Economic events represent either change of the property rights to economic resource or consumption or production of economic resources. This results from the essence of economic events and their connection to economic resources.

  13. Mucin-Based Vaccines

    Science.gov (United States)

    Richardson, Jonathan P.; MacMillan, Derek

    Mucins are heavily O-glycosylated cell surface and secreted glycoproteins . In addition to orchestrating cell-extracellular matrix and cell-cell interactions in healthy organisms mucins are also the major carriers of altered glycosylation in carcinomas. Tumor-associated antigens displayed by cancer cells comprise oligosaccharide and glycopeptide motifs not encountered in the same locale or at the same frequency in healthy cells, and potentially confer a selective advantage to the tumor. Frequently tumor-associated antigens are under-glycosylated and prematurely sialylated, and it is these relatively simple saccharide and glycopeptide structures that have been targeted to serve as drug candidates in most cases. A major goal is to assemble glycopeptide vaccine candidates based on partial mucin sequences and displaying tumor-associated antigens that can mount a potent immunological tumor-specific response when, in reality, the tumor has already coerced the immune system into a state of co-existence.

  14. Cellular based cancer vaccines

    DEFF Research Database (Denmark)

    Hansen, M; Met, Ö; Svane, I M

    2012-01-01

    -associated antigens introduced to dendritic cells (DCs) generated in vitro. This may in part result from suboptimal maturation of DCs leading to insufficient production of IL-12, a key driver of cellular immunity. Therefore, tremendous efforts have been put into the design of maturation cocktails that are able...... of tolerogenic molecules and activation-induced dendritic cell death should be avoided. Thus, compounds such as IFN-γ may initially induce immunity but later on tolerance. Maturation with PGE(2) obviously promotes migration via expression of CCR7 but on the down side PGE(2) limits the production of IL-12...... to transiently affect in vitro migration via autocrine receptor-mediated endocytosis of CCR7. In the current review, we discuss optimal design of DC maturation focused on pre-clinical as well as clinical results from standard and polarized dendritic cell based cancer vaccines....

  15. PROBLEM-BASED LEARNING

    Directory of Open Access Journals (Sweden)

    David Esema

    2012-12-01

    Full Text Available Problem-Based Learning (PBL, adalah model pembelajaran yang awalnya dikembangkan di dunia pendidikan medis, namun kini telah digunakan secara luas di berbagai jenjang dan bidang pendidikan. Basis teortits dari PBL adalah kolaborativisme dan konstruktivisme. Kemitraan, keterbukaan dan kejujuran, rasa hormat, dan kepercayaan menjadi nilai-nilai yang mendasari dan sekaligus menjadi prasyarat bagi keberhasilan PBL Sintaks PBL meliputi: pengenalan dan pemahaman konsep dasar, eksplorasi fakta dan informasi relevan secara mandiri, bertukar pemahaman dalam kelompok/kelas, kesimpulan dan evaluasi. Beberapa riset mengenai PBL baik di luar maupun di dalam negeri yang dipaparkan dan dibandingkan dalam tulisan ini menunjukkan data tentang efektifitas PBL dalam kegiatan pembelajaran.

  16. Graphene based biosensors

    Energy Technology Data Exchange (ETDEWEB)

    Gürel, Hikmet Hakan, E-mail: hhakan.gurel@kocaeli.edu.tr [Kocaeli University, Kocaeli (Turkey); Salmankurt, Bahadır [Sakarya University, Sakarya (Turkey)

    2016-03-25

    Nanometer-sized graphene as a 2D material has unique chemical and electronic properties. Because of its unique physical, chemical, and electronic properties, its interesting shape and size make it a promising nanomaterial in many biological applications. It is expected that biomaterials incorporating graphene will be developed for the graphene-based drug delivery systems and biomedical devices. The interactions of biomolecules and graphene are long-ranged and very weak. Development of new techniques is very desirable for design of bioelectronics sensors and devices. In this work, we present first-principles calculations within density functional theory to calculate effects of charging on nucleobases on graphene. It is shown that how modify structural and electronic properties of nucleobases on graphene by applied charging.

  17. Liaison based assembly design

    Energy Technology Data Exchange (ETDEWEB)

    Ames, A.; Kholwadwala, D.; Wilson, R.H.

    1996-12-01

    Liaison Based Assembly Design extends the current information infrastructure to support design in terms of kinematic relationships between parts, or liaisons. These liaisons capture information regarding contact, degrees-of-freedom constraints and containment relationships between parts in an assembly. The project involved defining a useful collection of liaison representations, investigating their properties, and providing for maximum use of the data in downstream applications. We tested our ideas by implementing a prototype system involving extensions to Pro/Engineer and the Archimedes assembly planner. With an expanded product model, the design system is more able to capture design intent. When a product update is attempted, increased knowledge availability improves our ability to understand the effect of design changes. Manufacturing and analysis disciplines benefit from having liaison information available, so less time is wasted arguing over incomplete design specifications and our enterprise can be more completely integrated.

  18. Lunar based massdriver applications

    Science.gov (United States)

    Ehresmann, Manfred; Gabrielli, Roland Atonius; Herdrich, Georg; Laufer, René

    2017-05-01

    The results of a lunar massdriver mission and system analysis are discussed and show a strong case for a permanent lunar settlement with a site near the lunar equator. A modular massdriver concept is introduced, which uses multiple acceleration modules to be able to launch large masses into a trajectory that is able to reach Earth. An orbital mechanics analysis concludes that the launch site will be in the Oceanus Procellarum a flat, Titanium rich lunar mare area. It is further shown that the bulk of massdriver components can be manufactured by collecting lunar minerals, which are broken down into its constituting elements. The mass to orbit transfer rates of massdriver case study are significant and can vary between 1.8 kt and 3.3 megatons per year depending on the available power. Thus a lunar massdriver would act as a catalyst for any space based activities and a game changer for the scale of feasible space projects.

  19. Model Based Temporal Reasoning

    Science.gov (United States)

    Rabin, Marla J.; Spinrad, Paul R.; Fall, Thomas C.

    1988-03-01

    Systems that assess the real world must cope with evidence that is uncertain, ambiguous, and spread over time. Typically, the most important function of an assessment system is to identify when activities are occurring that are unusual or unanticipated. Model based temporal reasoning addresses both of these requirements. The differences among temporal reasoning schemes lies in the methods used to avoid computational intractability. If we had n pieces of data and we wanted to examine how they were related, the worst case would be where we had to examine every subset of these points to see if that subset satisfied the relations. This would be 2n, which is intractable. Models compress this; if several data points are all compatible with a model, then that model represents all those data points. Data points are then considered related if they lie within the same model or if they lie in models that are related. Models thus address the intractability problem. They also address the problem of determining unusual activities if the data do not agree with models that are indicated by earlier data then something out of the norm is taking place. The models can summarize what we know up to that time, so when they are not predicting correctly, either something unusual is happening or we need to revise our models. The model based reasoner developed at Advanced Decision Systems is thus both intuitive and powerful. It is currently being used on one operational system and several prototype systems. It has enough power to be used in domains spanning the spectrum from manufacturing engineering and project management to low-intensity conflict and strategic assessment.

  20. DNA-based machines.

    Science.gov (United States)

    Wang, Fuan; Willner, Bilha; Willner, Itamar

    2014-01-01

    The base sequence in nucleic acids encodes substantial structural and functional information into the biopolymer. This encoded information provides the basis for the tailoring and assembly of DNA machines. A DNA machine is defined as a molecular device that exhibits the following fundamental features. (1) It performs a fuel-driven mechanical process that mimics macroscopic machines. (2) The mechanical process requires an energy input, "fuel." (3) The mechanical operation is accompanied by an energy consumption process that leads to "waste products." (4) The cyclic operation of the DNA devices, involves the use of "fuel" and "anti-fuel" ingredients. A variety of DNA-based machines are described, including the construction of "tweezers," "walkers," "robots," "cranes," "transporters," "springs," "gears," and interlocked cyclic DNA structures acting as reconfigurable catenanes, rotaxanes, and rotors. Different "fuels", such as nucleic acid strands, pH (H⁺/OH⁻), metal ions, and light, are used to trigger the mechanical functions of the DNA devices. The operation of the devices in solution and on surfaces is described, and a variety of optical, electrical, and photoelectrochemical methods to follow the operations of the DNA machines are presented. We further address the possible applications of DNA machines and the future perspectives of molecular DNA devices. These include the application of DNA machines as functional structures for the construction of logic gates and computing, for the programmed organization of metallic nanoparticle structures and the control of plasmonic properties, and for controlling chemical transformations by DNA machines. We further discuss the future applications of DNA machines for intracellular sensing, controlling intracellular metabolic pathways, and the use of the functional nanostructures for drug delivery and medical applications.

  1. Organic Biochar Based Fertilization

    Science.gov (United States)

    Schmidt, Hans-Peter; Pandit, Bishnu Hari; Cornelissen, Gerard; Kammann, Claudia

    2017-04-01

    Biochar produced in cost-efficient flame curtain kilns (Kon-Tiki) was nutrient enriched either with cow urine or with dissolved mineral (NPK) fertilizer to produce biochar-based fertilizers containing between 60-100 kg N, 5-60 kg P2O5 and 60-100 kg K2O, respectively, per ton of biochar. In 21 field trials nutrient-enriched biochars were applied at rates of 0.5 to 2 t ha-1 into the root zone of 13 different annual and perennial crops. Treatments combining biochar, compost and organic or chemical fertilizer were evaluated; control treatments contained the same amounts of nutrients but without biochar. All nutrient-enriched biochar substrates improved yields compared to their respective no-biochar controls. Biochar enriched with dissolved NPK produced on average 20% ± 5.1% (N=4) higher yields than standard NPK fertilization without biochar. Cow urine-enriched biochar blended with compost resulted on average in 123% ± 76.7% (N=13) higher yields compared to the organic farmer practice with cow urine-blended compost and outcompeted NPK-enriched biochar (same nutrient dose) by 103% ± 12.4% (N=4) on average. 21 field trials robustly revealed that low-dosage root zone application of organic biochar-based fertilizers caused substantial yield increases in rather fertile silt loam soils compared to traditional organic fertilization and to mineral NPK- or NPK-biochar fertilization. This can likely be explained by the nutrient carrier effect of biochar causing a slow nutrient release behavior, more balanced nutrient fluxes and reduced nutrient losses especially when liquid organic nutrients are used for the biochar enrichment. The results promise new pathways for optimizing organic farming and improving on-farm nutrient cycling.

  2. Mainstreaming gesture based interfaces

    Directory of Open Access Journals (Sweden)

    David Procházka

    2013-01-01

    Full Text Available Gestures are a common way of interaction with mobile devices. They emerged especially with the iPhone production. Gestures in currently used devices are usually based on the original gestures presented by Apple in its iOS (iPhone Operating System. Therefore, there is a wide agreement on the mobile gesture design. In last years, it is possible to see experiments with gesture usage also in the other areas of consumer electronics and computers. The examples can include televisions, large projections etc. These gestures can be marked as spatial or 3D gestures. They are connected with a natural 3D environment rather than with a flat 2D screen. Nevertheless, it is hard to find a comparable design agreement within the spatial gestures. Various projects are based on completely different gesture sets. This situation is confusing for their users and slows down spatial gesture adoption.This paper is focused on the standardization of spatial gestures. The review of projects focused on spatial gesture usage is provided in the first part. The main emphasis is placed on the usability point-of-view. On the basis of our analysis, we argue that the usability is the key issue enabling the wide adoption. The mobile gesture emergence was possible easily because the iPhone gestures were natural. Therefore, it was not necessary to learn them.The design and implementation of our presentation software, which is controlled by gestures, is outlined in the second part of the paper. Furthermore, the usability testing results are provided as well. We have tested our application on a group of users not instructed in the implemented gestures design. These results were compared with the other ones, obtained with our original implementation. The evaluation can be used as the basis for implementation of similar projects.

  3. Telephone-Based Coaching.

    Science.gov (United States)

    Boccio, Mindy; Sanna, Rashel S; Adams, Sara R; Goler, Nancy C; Brown, Susan D; Neugebauer, Romain S; Ferrara, Assiamira; Wiley, Deanne M; Bellamy, David J; Schmittdiel, Julie A

    2017-03-01

    Many Americans continue to smoke, increasing their risk of disease and premature death. Both telephone-based counseling and in-person tobacco cessation classes may improve access for smokers seeking convenient support to quit. Little research has assessed whether such programs are effective in real-world clinical populations. Retrospective cohort study comparing wellness coaching participants with two groups of controls. Kaiser Permanente Northern California, a large integrated health care delivery system. Two hundred forty-one patients who participated in telephonic tobacco cessation coaching from January 1, 2011, to March 31, 2012, and two control groups: propensity-score-matched controls, and controls who participated in a tobacco cessation class during the same period. Wellness coaching participants received an average of two motivational interviewing-based coaching sessions that engaged the patient, evoked their reason to consider quitting, and helped them establish a quit plan. Self-reported quitting of tobacco and fills of tobacco cessation medications within 12 months of follow-up. Logistic regressions adjusting for age, gender, race/ethnicity, and primary language. After adjusting for confounders, tobacco quit rates were higher among coaching participants vs. matched controls (31% vs. 23%, p Coaching participants and class attendees filled tobacco-cessation prescriptions at a higher rate (47% for both) than matched controls (6%, p coaching was as effective as in-person classes and was associated with higher rates of quitting compared to no treatment. The telephonic modality may increase convenience and scalability for health care systems looking to reduce tobacco use and improve health.

  4. Loyalty-based management.

    Science.gov (United States)

    Reichheld, F F

    1993-01-01

    Despite a flurry of activities aimed at serving customers better, few companies have systematically revamped their operations with customer loyalty in mind. Instead, most have adopted improvement programs ad hoc, and paybacks haven't materialized. Building a highly loyal customer base must be integral to a company's basic business strategy. Loyalty leaders like MBNA credit cards are successful because they have designed their entire business systems around customer loyalty--a self-reinforcing system in which the company delivers superior value consistently and reinvents cash flows to find and keep high-quality customers and employees. The economic benefits of high customer loyalty are measurable. When a company consistently delivers superior value and wins customer loyalty, market share and revenues go up, and the cost of acquiring new customers goes down. The better economics mean the company can pay workers better, which sets off a whole chain of events. Increased pay boosts employee moral and commitment; as employees stay longer, their productivity goes up and training costs fall; employees' overall job satisfaction, combined with their experience, helps them serve customers better; and customers are then more inclined to stay loyal to the company. Finally, as the best customers and employees become part of the loyalty-based system, competitors are left to survive with less desirable customers and less talented employees. To compete on loyalty, a company must understand the relationships between customer retention and the other parts of the business--and be able to quantify the linkages between loyalty and profits. It involves rethinking and aligning four important aspects of the business: customers, product/service offering, employees, and measurement systems.

  5. Base Research Program

    Energy Technology Data Exchange (ETDEWEB)

    Everett Sondreal; John Hendrikson

    2009-03-31

    In June 2009, the Energy & Environmental Research Center (EERC) completed 11 years of research under the U.S. Department of Energy (DOE) Base Cooperative Agreement No. DE-FC26-98FT40320 funded through the Office of Fossil Energy (OFE) and administered at the National Energy Technology Laboratory (NETL). A wide range of diverse research activities were performed under annual program plans approved by NETL in seven major task areas: (1) resource characterization and waste management, (2) air quality assessment and control, (3) advanced power systems, (4) advanced fuel forms, (5) value-added coproducts, (6) advanced materials, and (7) strategic studies. This report summarizes results of the 67 research subtasks and an additional 50 strategic studies. Selected highlights in the executive summary illustrate the contribution of the research to the energy industry in areas not adequately addressed by the private sector alone. During the period of performance of the agreement, concerns have mounted over the impact of carbon emissions on climate change, and new programs have been initiated by DOE to ensure that fossil fuel resources along with renewable resources can continue to supply the nation's transportation fuel and electric power. The agreement has addressed DOE goals for reductions in CO{sub 2} emissions through efficiency, capture, and sequestration while expanding the supply and use of domestic energy resources for energy security. It has further contributed to goals for near-zero emissions from highly efficient coal-fired power plants; environmental control capabilities for SO{sub 2}, NO{sub x}, fine respirable particulate (PM{sub 2.5}), and mercury; alternative transportation fuels including liquid synfuels and hydrogen; and synergistic integration of fossil and renewable resources (e.g., wind-, biomass-, and coal-based electrical generation).

  6. Integrated Agent-based and Case-based Reasoning System

    International Nuclear Information System (INIS)

    Mohamed, A.H.

    2014-01-01

    Increasing the complexity of the modern systems drives to use multiple case bases in the case based reasoning (CBR) system to solve a single problem. Sometimes, it is difficult and unman gable task to store the knowledge of the domain of these complex systems in a single case base. On the other hand, usually these multiple case bases having different structures that cause main limitation for solving the problem. This research introduces integrating the case based systems using multiple case bases with agent-based technique. This enables the system to use different case base structures. The proposed system has been applied for designing the radiotherapy of the kidney, liver and skin cancers. It is found that, the suggested system has simplified, managed the complexity, increasing the accuracy of the of CBR systems. Therefore, it can be applied with a good performance for the practical sites

  7. A comparison between centre-based and expedition-based ...

    African Journals Online (AJOL)

    A comparison between centre-based and expedition-based (wilderness) adventure experiential learning regarding group effectiveness: A mixed methodology ... it is strongly recommended that a centre-based adventure program be used – mainly on account of active involvement, intensive social interaction and continuous ...

  8. NMR studies concerning base-base interactions in oligonucleotides

    International Nuclear Information System (INIS)

    Hoogen, Y.T. van den.

    1988-01-01

    Two main subjects are treated in the present thesis. The firsst part principally deals with the base-base interactions in single-stranded oligoribonucleotides. The second part presents NMR and model-building studies of DNA and RNA duplexes containing an unpaired base. (author). 242 refs.; 26 figs.; 24 tabs

  9. Implementation of Task-based and problem-based ...

    African Journals Online (AJOL)

    This paper describes implementation of new task-based and problem-based pharmacotherapy course for 3rd year pre-clinical medical students at Faculty of Medicine and Health Sciences, Omdurman Islamic University. Keywords: Pharmacotherapy, Task-based learning, P -drug. Sudan Journal of Medical Science Vol.

  10. Flow-Based Provenance

    Directory of Open Access Journals (Sweden)

    Sabah Al-Fedaghi

    2017-02-01

    Full Text Available Aim/Purpose: With information almost effortlessly created and spontaneously available, current progress in Information and Communication Technology (ICT has led to the complication that information must be scrutinized for trustworthiness and provenance. Information systems must become provenance-aware to be satisfactory in accountability, reproducibility, and trustworthiness of data. Background:\tMultiple models for abstract representation of provenance have been proposed to describe entities, people, and activities involved in producing a piece of data, including the Open Provenance Model (OPM and the World Wide Web Consortium. These models lack certain concepts necessary for specifying workflows and encoding the provenance of data products used and generated. Methodology: Without loss of generality, the focus of this paper is on OPM depiction of provenance in terms of a directed graph. We have redrawn several case studies in the framework of our proposed model in order to compare and evaluate it against OPM for representing these cases. Contribution: This paper offers an alternative flow-based diagrammatic language that can form a foundation for modeling of provenance. The model described here provides an (abstract machine-like representation of provenance. Findings: The results suggest a viable alternative in the area of diagrammatic representation for provenance applications. Future Research: Future work will seek to achieve more accurate comparisons with current models in the field.

  11. Refractory metal based superalloys

    International Nuclear Information System (INIS)

    Alonso, Paula R.; Vicente, Eduardo E.; Rubiolo, Gerardo H.

    1999-01-01

    Refractory metals are looked as promising materials for primary circuits in fission reactors and even as fusion reactor components. Indeed, superalloys could be developed which take advantage of their high temperature properties together with the benefits of a two- phase (intermetallic compound-refractory metal matrix) coherent structure. In 1993, researchers of the Office National d'Etudes et de Recherches Aerospatiales of France reported the observation of such a coherent structure in the Ta-Ti-Zr-Al-Nb-Mo system although the exact composition is not reported. The intermetallic compound would be Ti 2 AlMo based. However, the formation of this compound and its possible coexistence with a disordered bcc phase in the ternary system Ti-Al-Mo is a controversial subject in the related literature. In this work we develop a technique to obtain homogeneous alloys samples with 50 Ti-25 Al-25 Mo composition. The resulting specimens were characterized by optical and electronic metallography (SEM), microprobe composition measurements (EPMA) and X-ray diffraction (XRD) analyses. The results show the evidence for a bcc (A2→B2) ordering reaction in the Ti-Al-Mo system in the 50 Ti-25 Al-25 Mo composition. (author)

  12. Fluorescence lifetime based bioassays

    Science.gov (United States)

    Meyer-Almes, Franz-Josef

    2017-12-01

    Fluorescence lifetime (FLT) is a robust intrinsic property and material constant of fluorescent matter. Measuring this important physical indicator has evolved from a laboratory curiosity to a powerful and established technique for a variety of applications in drug discovery, medical diagnostics and basic biological research. This distinct trend was mainly driven by improved and meanwhile affordable laser and detection instrumentation on the one hand, and the development of suitable FLT probes and biological assays on the other. In this process two essential working approaches emerged. The first one is primarily focused on high throughput applications employing biochemical in vitro assays with no requirement for high spatial resolution. The second even more dynamic trend is the significant expansion of assay methods combining highly time and spatially resolved fluorescence data by fluorescence lifetime imaging. The latter approach is currently pursued to enable not only the investigation of immortal tumor cell lines, but also specific tissues or even organs in living animals. This review tries to give an actual overview about the current status of FLT based bioassays and the wide range of application opportunities in biomedical and life science areas. In addition, future trends of FLT technologies will be discussed.

  13. Mentalization-Based Treatment.

    Science.gov (United States)

    Bateman, Anthony; Fonagy, Peter

    2013-11-01

    The concept of mentalizing has captured the interest and imagination of an astonishing range of people-from psychoanalysts to neuroscientists, from child development researchers to geneticists, from existential philosophers to phenomenologists-all of whom seem to have found it useful. According to the Thompson Reuter maintained Web of Science, the use of the term in titles and abstracts of scientific papers increased from 10 to 2,750 between 1991 and 2011. Clinicians in particular have enthusiastically embraced the idea, and have put it to innovative use in their practices. Mentalization-based treatment (MBT)-making mentalizing a core focus of therapy-was initially developed for the treatment of borderline personality disorder (BPD) in routine clinical services delivered in group and individual modalities. Therapy with mentalizing as a central component is currently being developed for treatment of numerous groups, including people with antisocial personality disorder, substance abuse, eating disorders, and at-risk mothers with infants and children (A. Bateman & Fonagy, 2011). It is also being used with families and adolescents, in schools, and in managing social groups (Asen & Fonagy, 2011; Fonagy et al., 2009; Twemlow, Fonagy, & Sacco, 2005a, 2005b). In this article, we focus on MBT in the treatment of BPD.

  14. Communication Base Station Log Analysis Based on Hierarchical Clustering

    Directory of Open Access Journals (Sweden)

    Zhang Shao-Hua

    2017-01-01

    Full Text Available Communication base stations generate massive data every day, these base station logs play an important value in mining of the business circles. This paper use data mining technology and hierarchical clustering algorithm to group the scope of business circle for the base station by recording the data of these base stations.Through analyzing the data of different business circle based on feature extraction and comparing different business circle category characteristics, which can choose a suitable area for operators of commercial marketing.

  15. Risk-based configuration control

    International Nuclear Information System (INIS)

    Szikszai, T.

    1997-01-01

    The presentation discusses the following issues: The Configuration Control; The Risk-based Configuration Control (during power operation mode, and during shutdown mode). PSA requirements. Use of Risk-based Configuration Control System. Configuration Management (basic elements, benefits, information requirements)

  16. Mindfulness-Based Stress Reduction

    Science.gov (United States)

    ... R S T U V W X Y Z Mindfulness-Based Stress Reduction (MBSR) Information 6 Things You ... Disease and Dementia (12/20/13) Research Spotlights Mindfulness-Based Stress Reduction, Cognitive-Behavioral Therapy Shown To ...

  17. ‘"Education-based Research"

    DEFF Research Database (Denmark)

    Degn Johansson, Troels

    This paper lays out a concept of education-based research-the production of research knowledge within the framework of tertiary design education-as an integration of problem-based learning and research-based education. This leads to a critique of reflective practice as the primary way to facilita...... learning at this level, a discussion of the nature of design problems in the instrumentalist tradition, and some suggestions as to how design studies curricula may facilitate education-based research....

  18. ASCOT data base management system

    Energy Technology Data Exchange (ETDEWEB)

    Barbieri, J.; Nyholm, R.; Castro, C.; Hill, K.

    1980-07-01

    The ASCOT data base management system is designed to handle the data produced by both the experimental and theoretical efforts of the DOE Atmospheric Studies in Complex Terrain (ASCOT) project. The data base envisioned is hierarchically structured, sparse, and compact. Information concerning any given data file is stored in a directory file. The data base management system uses a relational data management approach. Presently three management schema are being developed for use with the data base. 5 figures.

  19. Graphene based gene transfection

    Science.gov (United States)

    Feng, Liangzhu; Zhang, Shuai; Liu, Zhuang

    2011-03-01

    Graphene as a star in materials research has been attracting tremendous attentions in the past few years in various fields including biomedicine. In this work, for the first time we successfully use graphene as a non-toxic nano-vehicle for efficient gene transfection. Graphene oxide (GO) is bound with cationic polymers, polyethyleneimine (PEI) with two different molecular weights at 1.2 kDa and 10 kDa, forming GO-PEI-1.2k and GO-PEG-10k complexes, respectively, both of which are stable in physiological solutions. Cellular toxicity tests reveal that our GO-PEI-10k complex exhibits significantly reduced toxicity to the treated cells compared to the bare PEI-10k polymer. The positively charged GO-PEI complexes are able to further bind with plasmid DNA (pDNA) for intracellular transfection of the enhanced green fluorescence protein (EGFP) gene in HeLa cells. While EGFP transfection with PEI-1.2k appears to be ineffective, high EGFP expression is observed using the corresponding GO-PEI-1.2k as the transfection agent. On the other hand, GO-PEI-10k shows similar EGFP transfection efficiency but lower toxicity compared with PEI-10k. Our results suggest graphene to be a novel gene delivery nano-vector with low cytotoxicity and high transfection efficiency, promising for future applications in non-viral based gene therapy.Graphene as a star in materials research has been attracting tremendous attentions in the past few years in various fields including biomedicine. In this work, for the first time we successfully use graphene as a non-toxic nano-vehicle for efficient gene transfection. Graphene oxide (GO) is bound with cationic polymers, polyethyleneimine (PEI) with two different molecular weights at 1.2 kDa and 10 kDa, forming GO-PEI-1.2k and GO-PEG-10k complexes, respectively, both of which are stable in physiological solutions. Cellular toxicity tests reveal that our GO-PEI-10k complex exhibits significantly reduced toxicity to the treated cells compared to the bare PEI

  20. Home-based Healthcare Technology

    DEFF Research Database (Denmark)

    Verdezoto, Nervo

    of these systems target a specific treatment or condition and might not be sufficient to support the care management work at home. Based on a case study approach, my research investigates home-based healthcare practices and how they can inform future design of home-based healthcare technology that better account...