Nandam Harikrishna, Arun M. Isloor*, K. Ananda, Tanya Parish, Joazaizulfazli Jamalis, Hazem A. Ghabbour and Hoong-Kun Fun Pages 699 - 711 ( 13 )
Background: A new series of pyrazole containing 1,4-dihydropyridine derivatives 5a-i and 6a-i were synthesized from substituted acetylated aryls and substituted phenylhydrazine by the multistep reaction.Method: The target compounds 1,4-dihydropyridine derivatives were obtained from green synthesis of 1,3-disubstituted phenyl-1H-pyrazole-4-carbaldehydes 4a-i with ethyl acetoacetate and methyl acetoacetate at higher temperatures in the presence of ammonium acetate and the catalytic amount of ammonium metavanadate (NH4VO3). The role of ammonium metavanadate was increases rate of the reaction and obtained high yields. Result: Structures of newly synthesized 1,4-dihydropyridine moiety containing pyrazole derivatives were confirmed by FT-IR, NMR and Mass spectral studies. The structure of compound 5b was confirmed by S-XRD study. Further, these compounds were tested for in-vitro antitubercular and antimicrobial studies. Compounds 5a, 5b, 5i, 6a, 6b, 6g, 6h, and 6i were found to be active against all the bacterial microorganisms. Conclusion: The above mentioned compounds have shown lowest MIC ranging between 3.12-12.5 μg/ml against Mycobacterium tuberculosis and MIC values ranging between 7.8- 15.6 μg/ml for Mycobacterium smegmatis, Staphylococcus aureus and Pseudomonas aeruginosa. For the control of life threatening diseases such as tuberculosis, these eight compounds may be strongly promising synthetic compounds.
1, 3, 4-Trisubstituted pyrazole, 1, 4-dihydropyridine, multistep reaction, ammonium metavanadate, antitubercular study, antimicrobial studies.
Department of Chemistry, Medicinal Chemistry Laboratory, National Institute of Technology Karnataka, Surathkal, Mangalore 575025, Department of Chemistry, Medicinal Chemistry Laboratory, National Institute of Technology Karnataka, Surathkal, Mangalore 575025, Biological Sciences, Poornaprajna Institute of Scientific Research, Bangalore 562110, Drug Discovery, Infectious Disease Research Institute (IDRI), 1616 Eastlake, Avenue E, Suite 400, Seattle, WA 98102, Department of Chemistry, NMR Instrumentation, Universiti Teknologi Malaysia, 81310, UTM Skudai, Johor, Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P.O. Box. 2457 - Riyadh 11451, X-ray Crystallography, School of Physics, Universiti Sains Malaysia, Penang 11800