Nicotinic Acid Benzylidene/Phenyl-Ethylidene Hydrazides: Synthesis, Antimicrobial Evaluation and QSAR Studies

A series of nicotinic acid hydrazides (1-19) was synthesized and tested in vitro for antimycobacterial, antiviral, antibacterial and antifungal activities. The antimycobacterial activity results indicated that the presence of electron withdrawing halo groups improved the antimycobacterial activity. The antiviral evaluation showed that none of the synthesized derivatives inhibited the replication of viruses at subtoxic concentrations, except compounds 9 and 12. The antimicrobial screening results demonstrated that compounds having methoxy and 2-hydroxy naphthalene substituents were the most active ones against tested microbial strains. QSAR investigations revealed that multi-target QSAR models were found to be more effective in describing the antimicrobial activity than one-target QSAR models.