Synthesis, characterization and biological activity studies of certain 1-((benzo[d]thiazol-2-yl) methyl)-4,5-dihydro-3-methyl-N-phenyl-1H-pyrazol-5-imine and 2-((5-aryl-1H-1,2,4-triazol-3-yl) methyl)benzo[d]thiazoles

Abstract

In this work, 1-((benzo[d]thiazol-2-yl)methyl)-4,5-dihydro-3-methyl-N-phenyl-1H-pyrazol-5-imine (3a-h) have been successfully synthesized from the condensation of 2-((Benzo[d]thiazol-2-1-((benzo[d]thiazol-2-yl)methyl)-3-methyl-1H-pyrazol-5(4H)-one (2) with different aromatic amines. On the other hand, in another protocol, cyclization of 2-(benzo[d]thiazol-2-yl) acetohydrazide (4) with different aromatic aldehydes afforded 2-((5-aryl-1H-1,2,4-triazol-3-yl)methyl)benzo[d]thiazoles (5a-h). A perusal of the biological activity studies revealed that the derivatives having chlorine as substituent are more toxic to all six bacteria. Among the chloro group compounds, the compound which has methoxy group is more toxic.

Keywords:

• 2-((benzo[d]thiazol-2-1-((benzo[d]thiazol-2-yl)methyl)-3-methyl-1H-pyrazol-5(4H)-one
• condensation
• 1-((benzo[d]thiazol-2-yl)methyl)-4,5-dihydro-3-methyl-N-phenyl-1H-pyrazol-5-imine
• cyclization
• 2-(benzo[d]thiazol-2-yl) acetohydrazide
• 2-((5-aryl-1H-1,2,4-triazol-3-yl)methyl)benzo[d]thiazoles
• biological activity

Public Interest Statement

Over the years, pyrazole and thiazole derivatives received up surging attention and prominent importance among the family of heterocyclic azoles due to their proven biological, pharmaceutical, and agrochemical applications. The efficacy of clinical use of antiviral, anticancer, and antifungal drugs (Ribavirin, Anastrozole, Fluconazole, Voriconazole etc.) led to intense investigation of 1,2,4-triazole derivatives. A survey of literature depicted a series of many more biologically active heterocyclic compounds with pyrazole, pyrazoline, thiazole, thiazoline, and benzothiazole and benzothiazoline backbone. Stimulated by all such reports, the authors have taken up the synthesis, characterization and biological activity studies of certain 1-((benzo[d]thiazol-2-yl) methyl)-4,5-dihydro-3-methyl-N-aryl-1H-pyrazol-5-amines and 2-((5-aryl-1H-1,2,4-triazol-3-yl) methyl)benzo[d]thiazoles.

Acknowledgments

The authors sincerely thank the authorities of Osmania University in the Department of Chemistry (main campus), O.U.P.G. College (Saifabad campus) for constant support and timely help.

Additional information

Notes on contributors

Pathki Uma

Prof. Pondichery Kuppuswamy Saiprakash completed his PhD in Physical Chemistry in 1974 from Osmania University, Hyderabad, while Prof. Kamatala Chinna Rajanna has obtained PhD, under the supervision of Saiprakash in 1982 from the same University. Both the professors are still actively involved in green chemistry, catalysis and materials chemistry research, in the Department of Chemistry, Osmania University, Hyderabad, which is celebrating centenary year activities. Over 40 years of teaching and research experience, both of them published about 150 papers in prestigious national and international journals. Under their supervision, several students obtained PhD in chemical sciences. Mrs. Pathki Uma and Firasath Unnisa are working as Assistant Professors in Osmania University Hyderabad and active in research.