Organic Communications Articles
Issue: 2 April-June
Year: 2011 Volume: 4 Issue:2 April-June
1) Tandem synthesis of novel 4-(azidocarbonyl)phenylazide from 3-(4-hydrazinocarbonyl)phenylsydnone and its chemoselective 1,3 dipolar cycloaddition reaction and Curtius rearrangement
C The 4-(azidocarbonyl)phenylazide 3 obtained from 4-(hydrazinocarbonyl) phenylsydnone 1 by tandem hydrolysis – diazotisation, is used as the key intermediate for the chemoselective one-pot 1,3- dipolar cycloaddition reaction with dimethylacetylene dicarboxylate (DMAD) along with Curtius rearrangement affording the carbamates 5a-c and the isocyanate 6. These compounds were further used as building blocks for the triheterocyclic carbamates 9a-c and 10a-c and 4- triazolophenylaryl ureas 7a-f. The ethyl carbamate derivative 5a exhibited antibacterial inhibition selectively against B.subtilis almost one and half times more than Norfloxacin while compounds 5a, 7b and 10c were as active as Griseofulvin against A.flavusKeywords 4-(Hydrazinocarbonyl)phenylsydnone 4-(Azidocarbonyl)phenylazide Curtius rearrangement 1 3-dipolar cycloaddition DETAILS PDF OF ARTICLE © 2011 ACG Publications. All rights reserved.
2) A Facile, Choline Chloride/Urea Catalyzed Solid Phase Synthesis of Coumarins via Knoevenagel Condensation
The influence of choline chloride/urea ionic liquid in solid phase on the Knoevenagel condensation is demonstrated. The active methylene compounds such as meldrum’s acid, diethylmalonate, ethyl cyanoacetate, dimethylmalonate, were efficiently condensed with various salicylaldehydes in presence of choline chloride/urea ionic liquid without using any solvents or additional catalyst. The reaction is remarkably facile because of the air and water stability of the catalyst, and needs no special precautions. The reactions were completed within 1hr with excellent yields (95%). The products formed were sufficiently pure, and can be easily recovered. The use of ionic liquid choline chloride/urea in solid phase offered several significant advantages such as low cost, greater selectivity and easy isolation of products.Keywords Knoevenagel condensation coumarins choline chloride/urea meldrum’s acid ionic liquid. DETAILS PDF OF ARTICLE © 2011 ACG Publications. All rights reserved.
3) Synthesis and biological studies of novel 2-(4-substitutedbenzyl-thio)-5-amino-6-(benzo[d]thiazol-2-yl)-7-(4- chlorophenyl)pyrido--[2,3-d]-pyrimidin-4(3H)-one derivatives
A series of novel 2-(4-substitutedbenzylthio)-5-amino-6-(benzo[d]thiazol-2-yl)-7-(4-chlorophenyl)pyrido[2,3-d]pyrimidin-4(3H)-one derivatives were synthesized and evaluated for their antibacterial and antifungal activity. All the derivatives were efficiently synthesized in four steps. The structure of the newly synthesized compounds was elucidated by their IR, 1H-NMR, 13C NMR, LCMS mass spectra and elemental analysis.Keywords 2-(4-substitutedbenzylthio)-5-amino-6-(benzo[d]thiazol-2-yl)-7-(4-chlorophenyl)pyrido[2 3-d]-pyrimidin-4(3H)-one antibacterial antifungal. DETAILS PDF OF ARTICLE © 2011 ACG Publications. All rights reserved.
4) Synthesis and biological activity of 2-oxo-azetidine derivatives of phenothiazine
We have synthesized of N-[2-(10H-phenothiazinyl)ethyl]-4-(phenyl)-3-chloro-2-oxo-1-iminoazetidine 4(a-m). The structures of all the newly synthesized compounds were confirmed by IR, 1H NMR, 13C NMR and FAB-Mass and chemical methods. All synthesized compounds were evaluated for their antibacterial, antifungal and antitubercular activity which displayed acceptable results.Keywords Synthesis biological activity 2-azetidinone phenothiazine. DETAILS PDF OF ARTICLE © 2011 ACG Publications. All rights reserved.