Synthesis, Characterization and Biological Evaluation of Some New Heterocyclic Compounds Derived from 2-Naphthol

Abstract

The present study deals with the synthesis, spectroscopic characterization, antibacterial and antifungal activities of novel series five-membered ring heterocyclic compounds containing nitrogen and sulfur heteroatoms. The synthetic routes have been divided into two parts: The first one includes synthesis of compounds (4a-c) through one pot operation three component reaction of 2-naphthol (1), substituted benzaldehyde (2a-c) and thiourea (3) in 1,2-dichloromethane, using a catalytic amount of ZrOCl2.8H2O and compound (6) was synthesized using semicarbazide (5) in absolute ethanol and indium (III) chloride as catalyst. The second part is the hetero-cyclization reactions of the compounds (4a-c and 6) to obtain the heterocyclic compounds (7a-c, 8, and 9). The structures of the synthesized products are verified on the basis of (FT-IR, 1H-NMR and 13C-NMR) spectroscopy. The synthesized compounds antibacterial activities were screened against Staphylococcus aureus (Gram positive) and Escherichia coli (Gram negative) bacteria as compared to standard amikacin and antifungal activity against Candida albicans fungi as compared to standard Nystatin, well diffusion method is used. The antibacterial and antifungal activities of synthesized compounds (7a-c, 8 and 9) were higher than the antibacterial and antifungal activities of synthesized compounds (4a-c and 6).

Keywords

• three component reaction
• heterocyclic compound
• thiazole
• thiazolidin-4-one
• 1
• 2-dihydro-3h-1
• 2
• 4-triazol-3-one