A novel class of benzo [d]oxazol-2(3H)-one derivatives have been synthesized and evaluated their in vitro cytotoxicity against human pancreatic adenocarcinoma and human non small cell lung carcinoma cancer cell lines. Many of these compounds were found to display excellent to moderate activity. Among them, 6b, 6l, 6n and 6x are identified as lead molecules. In particular, 6l and 6n were found to be potent against 10 pancreatic cell line whereas the 6x was found to be effective against human non small cell lung carcinoma cell line. Conversely, the compounds 6l-x were found to ineffective against Mycobacterium tuberculosis. Of various molecules, 6h showed a promising anti-mycobacterial activity, which is equal to the IC 50 value of ciprofloxacin. Off White solid; 92% yield, m.p. 216-218 o C; 1 H NMR (400 MHz, DMSO): δ 10.35 (s, 1H), 8.41 (d, J = 7.2 Hz, 2H), 8.04 (s, 1H), 8.19 (d, J = 7.0 Hz, 2H), 7.59 (d, J = 8.2 Hz, 2H), 7.57 (m, 1H), 7.52 (s, 1H), 7.45 (m, 4H), 4.52 (m, 1H), 1.51 (d, J = 6.8 Hz, 6H);