Abstract

SYNTHESIS AND BIOLOGICAL EVALUATION OF NEW 10-(6- SUBSTITUTED-[1,2,4]-TRIAZOLO-[3,4-b][1,3,4]-THIADIAZOL-3- YLMETHYL)-3-NITRO-10H-PHENOXAZINE AND 10-(6- SUBSTITUTED-7H-[1,2,4]-TRIAZOLO-[3,4-b][1,3,4]-THIADIAZIN-3- YLMETHYL)-3-NITRO-10H-PHENOXAZINE

Kiran Kumar Murahari, Sunitha Kanakam, Bhupathi Reddy Kalam, JayanthKumar Molugu, Shobha Rani N, Mohan Rao Gangula,Vijaya Kumar Baru*

ABSTRACT

In the present study, a series of 10-(6-substituted-[1,2,4]-triazolo-[3,4- b][1,3,4]-thiadiazol-3-ylmethyl)-3-nitro-10H-phenoxazine (6a-6d) and 10-(6-substituted-[1,2,4]-triazolo-[3,4-b][1,3,4]-thiadiazin-3- ylmethyl)-3-nitro-10H-phenoxazine (7a-7k) were synthesized starting from 3-nitro-10H-phenoxazine (1). Compound 1 was converted to (3- nitro-phenoxazin-10-yl)acetic acid ethyl ester (2) on reaction with ethylbromoacetate. The ethyl ester gave on reaction with hydrazine hydrate (3-nitro-phenoxazin-10-yl)-aceticacidhydrazide (3), which on reaction with carbon disulphide provided carbodithioicacid potassium salt (4). The potassium salt 4 on reaction with hydrazine hydrate gave 4-amino-5-(3-nitro-phenoxazin-10-ylmethyl)-4H-[1,2,4]-triazole-3- thiol (5). The thiol 5 on reaction with various aromatic acids and phenacylbromides gave the title compounds (6a-6d) and (7a-7k) respectively. All the synthesized compounds have been characterized by IR, 1H NMR and Mass spectral data together with elemental analysis. These compounds were screened for antibacterial and antifungal activities using the chloramphinicol and fluconazole as internal standards. The results of the compounds 6a, 6b, 7f, 7g, 7j, 7i showed the higher antibacterial activity against gram positive bacteria. The results of the compounds 7a, 7b, 7c, 7d, 7e, 7g, and 7j showed the higher antibacterial activity against gram negative bacteria. Compound 6b, 6c, 7b, 7c and 7e showed good antifungal activity compared with internal standard.

Keywords: 4-Amino -5- (3-nitrophenoxazin-10-ylmethyl) - 4H- [1,2,4] – triazole – 3 - thiol, Antibacterial activity, Antifungal activity.