Regioselective Synthesis and Reactions of a Polynuclear Heterocyclic Derived From Pyrido[2,3-d]pyrimidines With a New Ring System

Abstract

2-thioxopyrido[2,3-d]pyrimidin-4-(1H)-ones 3 were synthesized by a reaction of α,β-unsaturated ketones with aminouracil. A series of pyrido[2,3-d]pyrimidine derivatives have been synthesized by a reaction of 3 with arylaldehydes, hydroxylamine hydrochloride, alkyl halides, arylazoketones, hydrazine hydrate, and thioureas to give a series of a new polynuclear heterocyclic ring added to parent compound 3 with a new ring system. 2-methylthio derivatives were converted to corresponding 2-methylsulphone derivatives 16 on treatment with hydrogen peroxide.

Keywords:

• 6-Amino-thiouracil
• pyrido[2,3-d]pyrimidine
• isoxazolothiazolopyridopyrimidine
• thiazolopyridopyrimidine
• ¹³C NMR