Synthesis and pharmacological investigation of novel 3-(3-methylphenyl)-2-substituted amino-3H-quinazolin-4-ones as analgesic and anti-inflammatory agents

A variety of novel 3‐(3‐methylphenyl)‐2‐substituted amino‐3H‐quinazolin‐4‐ones were synthesized by reacting the amino group of 2‐hydrazino‐3‐(3‐methylphenyl)‐3H‐quinazolin‐4‐one with a variety of aldehydes and ketones. The starting material 2‐hydrazino‐3‐(3‐methylphenyl)‐3H‐quinazolin‐4‐one was synthesized from 3‐methyl aniline. The title compounds were investigated for analgesic, anti‐inflammatory and ulcerogenic index activities. Compound 2‐(1‐ethylpropylidene‐hydrazino)‐3‐(3‐methylphenyl)‐3H‐quinazolin‐4‐one (AS2) was the most active analgesic agent. Compound 2‐(1‐methylbutylidene‐hydrazino)‐3‐(3‐methylphenyl)‐3H‐quinazolin‐4‐one (AS3) was the most active anti‐inflammatory agent and was moderately more potent than the reference standard diclofenac sodium. The test compounds showed only mild ulcerogenic potential compared with aspirin.