Synthesis, Antimicrobial Activity of Some New 2-Amino-4-(4′-phenylsulfanyl-phenyl)-thiazole Derivatives and Theoretical Studies of Their Schiff's Base

• Published in: Phosphorus, sulfur, and silicon and the related elements sulfur, and silicon and the related elements, 2003-12, Vol.178 (12), p.2563-2579
• Main Author: Abdel-Hafez, Sh. H.
• Format: Article
• Language: English
• Subjects: Antimicrobial activity; Schiff's base; stereochemistry; synthesis; thiazolopyrimidines
• ISSN: 1042-6507; 1563-5325
• DOI: 10.1080/714040970

2-Amino-4-(4′-phenylsulfanyl-phenyl)-thiazole (2) has been obtained from reaction of 4-chloroacetyl diphenyl sulfide (1) with thiourea. Compound (2) reacted with active methylene derivatives, e.g., diethylmalonate or ethylcyano acetate to give fused thiazolo-pyrimidines (3-6) under variable conditions. Other substituted thiazolo-pyrimidines (7-9) also have been prepared by the reaction of (2) with some arylidine malonitriles (benzylidinemalononitrile and ethylbenzylidinecyano-acetate). On treatment of schiff's bases (10 a-c ) with phenylisothiocyanate, the corresponding thiazolo-s-triazines (11 a-c ) were formed. Reaction of (2) with carbon disulfide in the presence of concentrated aqueous sodium hydroxide and DMF as solvent gave the sodium salt of dithiocarboimidic acid which, on treatment with 1 mmol of ethyl iodide, gave monoethylated product (12). Reaction of (12) with anthranilic acid yielded (13). Interaction of (2) with 2 mmol of ethyl iodide afforded the diethylated product (14) which reacted with potassium salt of anthranilic acid to give (15). Also, (14) reacted with o-phenylenediamine yielded (16). The substituent effect on the stereochemistry of Schiff's bases (10 a-c ) was studied using Hyperchem (version 5). Compounds (2, 4, 6, 10 b , 12, 13, 14, 15) were tested to evaluate their antimicrobial activity.