10.22376/ijpbs.2019.10.1.p1-12 Volume 1 Issue 2 2010 (April - June)  A series of 3-(5-(2-fluorophenyl)-1,3,4-thiadiazol-2-yl)-2-((2-(5-(un/substituted hetetocyclic/aryl) -4,5dihydroisoxazol-3-yl)hydrazinyl)methyl)quinazolin-4(3H)-ones 6a-i have been synthesized by the reaction of 3-(5-(2-fluorophenyl)-1,3,4-thiadiazol-2-yl)-2-((2-(5-(un/substituted heterocyclic/ arylchalconyl)hydrazinyl)methyl)-substitutedquinazolin-4(3H)-one 5a-5i with hydroxyl amine hydrochloride in presence of 2% NaOH. All the newly synthesized compounds were screened for their antipsychotic and anticonvulsant activities. Structures of all the compounds were established by elemental and spectral (IR, 1H NMR and Mass) analysis.  Hemlata Kaur, Sunil Kumar K.K.Saxena and Ashok Kumar Thiadiazolylquinazolinones, Pyridiny/Indolyllquinazolinones, isoxazolylquinazolinones, antipsychotic activity, anticonvulsant activity, toxicity study. -