Heterocyclic analogues of 1, 2, 3-oxadiazolium-5-olate along with pyrazole ring and isoxazole ring have been designed for antineoplastic evaluation. A series of novel 4-[5-(aryl)-4, 5-dihydro-(1H-pyrazole/1-phenylpyrazol/ isoxazole)-3-yl]-3-(2-methyphenyl)-1,2,3-oxadiazolium-5-olates has been synthesized and evaluated against human prostate cancer cell line PC3 and human breast cancer cell line MDA-MB-231. Compound 2C was found to have moderate cytotoxic activity (GI50=56.9μg/ml). Further designing with modifications and in vivo study of synthesized 1, 2, 3-oxadiazolium-5-olates may give a ray of light to search for a potent antitumor molecule.