Looking for new cytotoxic and antimicrobial agents with improved antitumor activity, a series of hydrazide and oxadiazole derivatives were designed and synthesized using 3-methoxyphenol as starting substance. Novel N'-(arylidene)-2-(3-methoxyphenoxy) acetohydrazide derivatives (4a-f) / 1-(4-substitutedphenyl)-2-[(5-[(3-methoxyphenoxy) methyl]1,3,4- oxadiazol-2-yl) thio] ethan-1-one derivatives (6a-f)/N-(6-substitutedbenzothiazol-2-yl)-2-[(5-[(3-methoxyphenoxy) methyl]-1,3,4-oxadiazol-2-yl) thio] acetamide derivatives (7a-e) were obtained and evaluated for their in vitro antimicrobial activity against various gram-positive, gram-negative bacteria and fungi. The antimicrobial activity potential of the compounds against gram-negative bacteria was found to have higher compared to the potential against gram-positive bacteria. Also, compounds were screened for their antiproliferative activity against 2 selected human tumor cell lines, A549 lung, MCF7 breast cancer cell line and mouse embryo fibroblast cell line, NIH/3T3 as healthy cell line. Among the compounds evaluated, compound 7c bearing 1,3,4-oxadiazole ring and 6-methoxy benzothiazole moiety exhibited the highest inhibitory activity against A549 and MCF-7 tumor cell lines in contrary to NIH/3T3 cell line, as desired.