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1.
Racemic 4-(substituted-1H-1,2,3-triazol-1-yl), 4-aryl and 4-(arylmethyl)tetrazolyl-pyroglutamic and proline derivatives were synthesized from dimethyl-2,4-dibromoglutaryle 1 in good yield using mild reaction conditions. The key step for the preparation of the triazole substituted molecule was the 1,3-dipolar cycloaddition of an acetylenic compound with an azido derivative. The tetrazole derivatives were prepared by the selective N2-alkylation of 5-substituted tetrazoles with 1. 相似文献
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《Tetrahedron: Asymmetry》1999,10(22):4331-4341
The syntheses and resolutions of enantiomerically enriched 4-phenyl, 4-tert-butyl, and 4-isopropyl pipecolic acids are described. Optically active diastereomers were prepared by diastereomeric salt formation with the chiral base, l-tyrosine hydrazide, to provide Cbz or Boc protected 4-cis-d-pipecolic acid derivatives in >98% ee. Subsequent esterification followed by sodium methoxide catalyzed epimerization provided the isomeric 4-trans-l-pipecolic esters. In addition, an efficient synthesis of 4-phenyl-cis-pipecolic acid is described. 相似文献
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Laurent Le Corre 《Tetrahedron letters》2005,46(44):7495-7497
Two, orthogonally protected, constrained analogues of arginine have been synthesised in a diastereodivergent manner. The key step involved an electrophilic or radical functionalisation of methyl N-Boc-5,6-dehydropipecolate. 相似文献
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Andrey A. Prishchenko Mikhail V. Livantsov Olga P. Novikova Ludmila I. Livantsova Valery S. Petrosyan 《Heteroatom Chemistry》2008,19(5):470-473
Nucleophilic addition of trimethylsilyl esters of hypophosphorus acid to trimethylsilyl ester and diethylamide of vinylsulfonic acid is proposed as convenient methods for the synthesis of new 2‐sulfonylethylphosphonites and their derivatives under mild conditions. Also the new functionalized derivatives of these phosphonites, including aminomethyl fragments as well as certain properties of these compounds as important precursors of new organophosphorus‐substituted derivatives of ethanesulfonic acid, are presented. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:470–473, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20448 相似文献
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Mohamad D. Shalati C. G. Overberger 《Journal of polymer science. Part A, Polymer chemistry》1984,22(1):107-120
Racemic and optically active N-carboxyanhydrides (NCA)s of 2-methyl- and cis-6-methylpipecolic acid, when subjected to polymerization conditions in solution or in bulk whether with “weak” or “strong” base initiators, resisted polymerization under all conditions tried. Instead, the NCA of 2-methylpipecolic acid gave the corresponding cyclic dipeptide and the NCA of cis-6-methylpipecolic acid formed the cyclic dipeptide derived from trans-6-methylpipecolic acid. The mechanism of dimerization of these NCA's was investigated. Evidence was provided for the proposed mechanism in which the active moiety is not a carbamate ion but an amino group. Methyl 2-methylpipecolate underwent an intermolecular SN2-type reaction upon heating, yielding equimolar quantities of methyl N-methyl-2-methylpipecolate and 2-methylpipecolic acid. 相似文献
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Omar M. Ali Abd El-Galil E. Amr Elsayed E. Mostafa 《Research on Chemical Intermediates》2014,40(4):1545-1556
A series of tetrazolomethylbenzo[d][1,2,3]triazole derivatives (2–14) have been synthesized and evaluated as antimicrobial agents from 1H-benzo[d][1,2,3]triazole (1) as starting material. The reaction of benzotriazole 1 with chloroacetonitrile afforded 2-(1H-benzo[d][1,2,3]-triazol-1-yl)acetonitrile 2, which was reacted with sodium azide to give tetrazole derivative 3. Esterification of benzotriazole 1 with ethyl bromoacetate in the presence of anhydrous potassium carbonate afforded ester 4, which was treated with hydrazine hydrate to afford the corresponding hydrazide 5. Reaction of 3 with 2,3,4,6-tetra-O-acetyl-α-d-glucopyranosyl bromide afforded the nitro-glycoside derivative 6, which was deacetylated using methanolic ammonia to deprotected nitroglycoside 7. The hydrazide 5 was reacted with 4,5,6,7-tetrachlorophthalic anhydride or 1,2,4,5-benzenetetracarboxylic dianhydride in refluxing glacial acetic acid to give the corresponding imides 8 and 9, respectively. Also, the hydrazide 5 was reacted with carbon disulphide in ethanol to give potassium salt 10, which was reacted with hydrazine hydrate to afford aminotriazole derivative 11. The latter compound was reacted with carbon disulphide to afford thiadiazole derivative 12, which was treated with 2,3,4,6-tetra-O-acetyl-α-d-glucopyranosyl bromide to give the thioglycoside derivative 13. Deacetylation of the thioglycoside 13 using methanolic ammonia solution at room temperature afforded the deprotected thioglycoside 14. The antimicrobial screening of some synthesized compounds showed that many of these compounds have good antimicrobial activities comparable to streptomycin and fusidic acid as reference drugs. 相似文献
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Patrick D. Bailey George R. Brown Pritiof Korber Amanda Reed Robert D. Wilson 《Tetrahedron: Asymmetry》1991,2(12):1263-1282
Imines of the type R---N=CHCO2Et can be coerced into undergoing a (4+2) cycloaddition with substituted dienes if the reaction is carried out in DMF in the presence of both water and acid: these reactions show extremely high regio- and diastereoselectivity. Use of the 1-phenylethyl group as a chiral auxiliary leads to moderate asymmetric induction (typical d.e. ca. 70%); moreover, the diastereoisomers are surprisingly easy to separate, giving a short general route to optically pure substituted pipecolic acid derivatives. 相似文献
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Complementary new routes to both enantiomers of N-protected pipecolic acid and the corresponding 4,5-dihydroxylated derivatives are developed, which involve stereo-divergent allylation of a chiral N-allylimine and ring-closing metathesis as key steps. 相似文献
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Vinay Pogaku Ravi Kumar Eslavath G. Dayakar Surya S. Singh Srinivas Basavoju 《Research on Chemical Intermediates》2017,43(11):6079-6098
Novel triazole substituted pyrazolyl-methylenehydrazinyl-5-arylidene thiazolidinone derivatives 6a–n and 7a–l were synthesized and characterized by Fourier transform infrared, 1H and 13C nuclear magnetic resonance, mass spectrometry and elemental (CHN) analysis. The in vitro antibacterial (6a–n and 7a–l) and cytotoxic (6a–n) activities were evaluated for these compounds. The results revealed that the compounds 6b, 6i, 6k, 7b, 7h displayed good antibacterial activity. The compounds 6c (IC50 = 5.4 μM), 6l (IC50 = 6.3 μM) and 6f (IC50 = 9.85 μM) were effective for inhibition of human breast cancer cell line MCF-7. Similarly, the compounds 6b (IC50 = 8.7 μM) and 6c (IC50 = 9.06 μM) were shown to have effective inhibition on human cervical cancer cell line Hela. 相似文献
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Łukasz Popiołek Maria Dobosz Anna Chodkowska Ewa Jagiełło‐Wójtowicz Urszula Kosikowska Anna Malm Liliana Mazur Zofia Rzączyńska 《Journal of heterocyclic chemistry》2011,48(2):339-346
Reaction of 4‐phenyl‐4H‐1,2,4‐triazole‐3‐thione with ethyl bromoacetate has led to the formation of ethyl [(4‐phenyl‐4H‐1,2,4‐triazol‐3‐yl)sulfanyl]acetate 1 , the structure of which was confirmed by X‐ray analysis. In the next reaction with 80% hydrazide hydrate, appropriate hydrazide 2 was obtained, which in reaction with isothiocyanates was converted to new acyl derivatives of thiosemicarbazides 2 , 3 , 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h . The cyclization of these compounds in alkaline media has led to formation of new derivatives of 5‐{[(4‐phenyl‐4H‐1,2,4‐triazole‐3‐yl)sulfanyl]methyl}‐4H‐1,2,4‐triazole‐3(2H)‐thiones 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4j . The structure of the compounds was confirmed by elementary analysis and IR, 1H‐NMR, 13C‐NMR, and MS spectra. Compounds 2 , 3 , 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h and 4a , 4b , 4c , 4d , 4e , 4f , 4g were screened for their antimicrobial activities, and the influence of the compounds 4a , 4b , and 4e , 4f , 4g on the central nervous system of mice in behavioral tests was examined. J. Heterocyclic Chem., (2011). 相似文献
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Ying Chen Pu Li Mei Chen Jun He Shijun Su Ming He Hua Wang Wei Xue 《Journal of heterocyclic chemistry》2020,57(3):983-990
The infection of Xanthomonas oryzae pv. Oryzae (Xoo), Ralstonia solanacearum (Rs), and Xanthomonas axonopodis pv. Citri (Xac) has become a major problem in agricultural production. In this study, a series of novel chalcone derivatives containing thioether triazoles were designed and synthesized. The structures of the novel compounds were systematically characterized via 1H-NMR, 13C-NMR, and HRMS. Moreover, the antibacterial activity results showed that E10, E11, E15, and E16 have adequate antibacterial activities against Xoo, Rs, and Xac. Among the different compounds, E15 exhibited remarkable inhibitory effect against Xac with an EC50 of 9.1 μg.mL-1, which was better than that of commercial agent bismerthiazol (54.9 μg.mL-1). In addition, the possible antibacterial mechanism of the target compound E15 against Xac was studied via scanning electron microscopy (SEM). 相似文献
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Eeva Lankinen Gran Sundholm Panu Talonen Hanna Gran Franciska Sundholm 《Journal of Electroanalytical Chemistry》1999,460(1-2)
In this work, three new acrylate substituted thiophene monomers, (3-thienyl) methylacrylate, 6-(3-thienyl)methoxy-hexylacrylate and 11-(3-thienyl)methoxy-undecylacrylate were synthesized and electropolymerized. Electrochemical polymerisation by a potential step technique leads to the formation of an electroactive film on a Pt electrode in each case. The polymerization involves evidently only the thiophene ring, as no sign of polyacrylate formation could be detected. The oxidation of each polymer was studied by in situ external reflectance FTIR spectroscopy, which showed several bands assigned to (bi)polaron type charge carriers in the region 1500–1000 cm−1. The evolution of the conductivity was studied in situ by the contact electric resistance technique. The conductivity of poly(3-thienyl methacrylate) was found to be higher in aqueous solutions than in acetonitrile. The surface of poly((3-thienyl) methacrylate) was found to have a granular structure observed for many polythiophenes, as studied by atomic force microscopy (AFM). 相似文献
18.
Grzegorz M. Salamończyk 《Tetrahedron letters》2011,52(1):155-158
The efficient synthesis of new dendrimeric polyesters up to generation 3 that consist of 1,3,5-benzenetricarboxylic acid building blocks with potential applications in drug delivery is described. The dendrimers possess hydroxy or allyl functional groups on the surface and were prepared through a divergent approach using readily available 2-(hydroxymethyl)-2-ethylpropan-1,3-diol and 1,3,5-benzenetrimethanol as central cores, with 3,5-bis[(allyloxy)methyl]benzoic acid being an essential unit of the dendrimer. The latter compound was synthesized, in high yield, from 1,3,5-benzenetricarboxylic acid, applying selective hydrolysis of the corresponding triester as the key step. 相似文献
19.
Ribosylated 1,2,3‐triazole 4 and 5 were synthesized in moderate yields by the reaction of aroyl‐substituted heterocyclic ketene aminals 1 or 2 with 2,3,5‐tri‐O‐benzoyl‐β‐D ‐ribofuranosyl azide ( 3 ). Their structures were determined by elemental analyses and spectroscopic methods. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:487–490, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10167 相似文献
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V. V. Melyshenkova D. N. Kuznetsov A. G. Ruchkina K. I. Kobrakov 《Russian Chemical Bulletin》2018,67(5):878-883
New 1,3-dihydroxyacridine-9-carboxylic acids were obtained by Pfitzinger reaction from 2,4,6-trihydroxytoluene (methylphloroglucinol). Their bromination and azo-coupling reactions were studied. Computer simulation was used to determine potential pharmacokinetic and toxic properties of the synthesized compounds. 相似文献