Study on the Selective Reduction of 1H-Quinazoline-2,4-diones

The 1H-quinazoline-2,4-dione derivatives have attracted interests on their various biological activities including the selective serotonin-S2 antagonist.1 These compounds are structurally similar with quinazoline and quinazolinone derivatives and conventionally synthesized by the coupling of isocyanate with the amine group as nucleophile and by cyclization under the heating and basic conditions.2 From this main skeleton, the modified compounds had been synthesized for the desired biological activities. Of these, nonpeptide antagonists for the human gonadotropin-releasing hormone receptor were synthesized by modifying the C2 position and varying R2 derivatives.3 Other example is the thymidylate synthase inhibitor, ZD9331, developed by AstraZeneca.4 This compound was synthesized by modify-ing the C6 position. Recently, Ismail et al. designed an