A new series of thieno[2,3-b]pyridine-2-carbohydrazide, 2,3 dihydropyrido[3′,2′:4,5]-thieno[3,2-d]pyrimidin-4(1H)-one, thieno[2,3-b]pyridin-2 yl)(3,5-substituted-1H-pyrazol-1-yl)methanone, tetrazolopyrimidine, and triazolopyrimdine derivatives have been synthesized. Molecular docking studies were performed on the most active compounds against the aspartic protease from Candida albicnas (1ZAP) and gram-negative (Salmonella typhimurium) binding protein (3ZQB) revealed the potential binding mode of the ligands to the site of the appropriate targets. To determine the direction of the reaction, compounds (19a) and (20a) were subjected to a computational study. Computational investigations are in complete agreement with experimental findings. Moreover, the selected newly synthesized products were evaluated for their antimicrobial activity. [ABSTRACT FROM AUTHOR]