Synthesis of Novel Classes of Pyrido[2,3‐d]‐pyrimidines, Pyrano[2,3‐d]pyrimidines, and Pteridines

Abstract

6‐Amino‐5‐formyluracils 1 and 5‐formyl‐6‐hydroxyuracils 4 react with Meldrum's acid 2 in the presence of piperidine as catalyst under thermolytic conditions to afford 6‐carboxy‐2,4,7‐trioxopyrido[2,3‐d]pyrimidines 3 and 6‐carboxy‐2,4,7‐trioxopyrano[2,3‐d]pyrimidines 5 in good yield. Under identical conditions, 6‐amino‐5‐nitrosouracils 6 react with 2 to afford pteridine‐6‐carboxylic acids 7 in good yields.

Keywords:

• Meldrum's acid
• pteridines
• pyrano[2,3‐d]pyrimidines
• pyrido[2,3‐d]pyrimidines
• uracil

Acknowledgments

The authors thank the director, Regional Research Laboratory (RRL), Jorhat, for providing the facilities to perform the work. M. L. Deb thanks Council of Scientific & Industrial Research (CSIR), New Delhi, for the award of a junior research fellowship.