SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF 4-AMINO-3-(2'-PHENYLINDOL-3'-YL)-2-IMINO-4-THIAZOLINE-5-CARBONITRILES AND THEIR DERIVATIVES

Abstract

2-Phenyl-3-aminoindoles on reaction with benzoyl isothiocyanate furnished the respective N-(2-phenyl-3-indolyl)N'-benzoyl-thioureas, which on hydrolysis with alcoholic sodium hydroxide gave 2-phenyl-3-indolylthioureas (is - c). These thioureas on condensation with bromoamalononitrile afforded 4-amino-3-(2'-phenylindol-3'-yl)-2-imino-4-thiazoline-5-carbonitriles (2a-c.) On acetylation with acetic anhydride and glacial acetic acid at room temperature, as well as on heating, 2a-c yielded only 4-acetylamino-3-(2'-phenylindol-3-yl)-2-imino -4-thiazoline-5-carbonitriles (3a - c) but not the diacetyl derivatives (2a-c). Compounds 3a -c on heating with orthophosphoric acid followed by basification with aqueous ammonia afforded 4-acetylamino-3-(2'-phenylindol-3'-yl)-2-imino-4-thiazoline-5-carboxamides (4a - c), and under similar conditions, 4-amino-3-(2'-phenylindol-3'-yl)-2-amino-4-thiazoline-5-carboxamides (5a - c) were obtained directly from 2a - c. Compounds 2a - c on condensation with various isothiocyanates and phenylisocyanate yielded 4-alkyl/(p-substituted)-phenyl-thioureido-3-(2'-phenylindol-3'-yl)-2-imino-4-thiazoline-5-carbonitriles (6a - c) and 4-phenylureido-3-(2'-phenylindol-3'-yl)-2-imino-4-thiazoline-4-carbonitriles (7a - c), respectively.