A series of Ethyl-3-methyl-5-(substituted-phenyl)-6,7,8,9-tetrahydro-5H-thiazolo 2,3-b]quinazoline-2-carboxylate derivatives have been synthesize from cyclohexanone and substituted benzaldehyde with the aim of developing potential antimicrobials and antitubercular agents. It was characterized by FT-IR, 1H NMR and Mass spectroscopy. All the newly synthesized compounds were screened for their antimicrobial and antifungal activities on Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus luteus, Bacillus cereus (Gram-positive bacteria), Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia (Gram-negative bacteria), Aspergillus fumigates, Candida albicans (Fungi). All the synthesized compounds were also evaluated for their antitubercular activity against Mycobacterium tuberculosis strain H37Ra.