Synthesis of some new 2-amino-6-thiocyanato benzothiazole derivatives bearing 2,4-thiazolidinediones and screening of their in vitro antimicrobial, antitubercular and antiviral activities

A series of new (E)-2-(5-substituted benzylidene-2,4-dioxothiazolidin-3-yl)-N-(6-thiocyanatobenzo[d]thiazol-2-yl)acetamides have been synthesized. The structures of title compounds have been confirmed by elemental analyses, IR, 1H NMR and 13C NMR spectral data. All the synthesized compounds were tested for antimicrobial and antitubercular activity and also were evaluated for anti-HIV activity. Several compounds exhibited good antibacterial activity (9, 15, 27 and 31 against E. coli; 8 and 28 against S. aureus); some displayed good antifungal activity (4, 7, 13, 19, 23, 24, 25 and 31 against C. albicans). Compounds 14, 20 and 22 showed good antitubercular activity. Unfortunately, none of the compounds were found to be active against anti-HIV-1. However, one of the intermediates, the 2-chloro-N-(6-thiocyanatobenzo[d]thiazol-2-yl)acetamide, showed significant cytotoxicity for MT-4 cells (CC50 = 8.0 µM).