Novel synthesis and biological activity of 2-substituted derivatives of 3-cyano-4-imino-2-methylthio-8-methoxy-4H-pyrimido[2,1-b][1,3]benzothiazole and 3-amino-4-imino-8-methoxy-2H-pyrazolo[3′,4′:4,5]pyrimido[2,1-b][1,3]benzothiazole

✍ Scribed by S. G. Badne; D. K. Swamy; V. N. Bhosale; S. V. Kuberkar

• Publisher: Journal of Heterocyclic Chemistry
• Year: 2011
• Tongue: English
• Weight: 183 KB
• Volume: 48
• Category: Article
• ISSN: 0022-152X
• DOI: 10.1002/jhet.559

✦ Synopsis

Abstract

2‐Amino‐6‐methoxybenzothiazole 1 on reaction with bis(methylthio)methylene malononitrile 2 in the presence of dimethyl formamide and catalytic amount of anhydrous potassium carbonate afforded 3‐cyano‐4‐imino‐8‐methoxy‐4__H__‐pyrimido[2,1‐b][1,3]benzothiazole 3. Under similar experimental conditions, compound 3 on treatment independently with arylamines/heterylamines/phenols/compounds containing active methylene group yielded corresponding 2‐substituted derivatives of compound 3 (4a, 4b, 4c, 4d, 5a, 5b, 5c, 6a, 6b, 6c, 6d, 6e, and 7a, 7b, 7c, 7d, 7e). Similarly, novel heterocyclic compounds, 3‐amino‐4‐imino‐8‐methoxy‐2__H__
8a/aryl 8b~–c~/heteryl 8d, 8e, 8f/pyrazolo[3′,4′:4,5]pyrimido[2,1‐b][1,3]benzothiazoles, were prepared by heating compound 3 independently with hydrazine hydrate/arylhydrazines/heterylhydrazines, respectively. All these newly synthesized compounds were screened for antimicrobial activity. J. Heterocyclic Chem., (2011).