Synthesis and Antibacterial and Antifungal Activity of New Thieno[2,3-d]Pyrimidin-4(3H)-One Derivatives

Abstract

A series of new 2-(4/3-substitutedbenzyl)thieno[2,3-d]pyrimidin-4(3H)-ones (2a-f) and 2-(4/3-substituted benzyl)-5,6,7,8-tetrahydrobenzo[4,5]thieno[2,3-d]pyrimidin-4(3H)-one derivatives (3a-f) were synthesized for the first time by the reaction of corresponding 2-aminothiophene-3-carboxamide derivatives and appropriate iminoester hydrochlorides under suitable conditions. Using microdilution method, the antibacterial and antifungal activities of the synthesized compounds were tested against selected strains of Gram positive and Gram negative bacteria (Staphylococcus aureus, Enterecoccus faecalis, Escherichia coli and Pseudomonas aeruginosa) and yeast-like fungi (Candida albicans, C. krusei and C. parapsilosis). In these tests, compounds 3a-f showed higher antifungal activity than fluconazole against Candida fungus species. 2-Substituted thieno-[2,3-d]pyrimidin-4(3H)-ones (2a-f) showed better antibacterial activity than 2-substituted 5,6,7,8-tetrahydrobenzo[4,5]thieno[2,3-d]pyrimidin-4(3H)-one derivatives (3a-f). © 2020, Springer Science+Business Media, LLC, part of Springer Nature.