Nucleosides 11: synthesis of new derivatives of pyrido[2,3-d]pyrimidines and their nucleosides

Abstract

Reaction of 6-amino-2-methylthio-3-methyluracil with ethyl ethoxymethyleneoxaloacetate or methyl(Z)-2-acetylamino-3-dimethylaminopropenoates afforded diethyl 2-(1,6-dihydro-1-methyl-2-(methylthio)-6-oxopyrimidin-4-yl-amino)methylene malonate or (2E)-methyl 3-(1,6-dihydro-1-methyl-2-(methylthio)-6-oxopyrimidin-4-yl-amino)-2-acetamidoacrylate, respectively. Cyclization of each of the latter products by sodium ethoxide afforded new pyrido [2,3-d]pyrimidines, which were ribosylated with 1-O-acetyl-2,3,5-O-benzoyl-β-D-ribofuranose by the silylation method yielded the protected nucleosides. The protected nucleosides were debenzoylated by sodium methoxide to afford novel pyrido[2,3-d]pyrimidine nucleosides. The structural assignmentsv for the new compounds were based on their elemental analysis and spectroscopic data.

Keywords:

• 6-Amino-2-methylthio-3-methyluracil
• ethyl ethoxymethyleneoxaloacetate
• methyl(Z)-2-acetylamino-3-dimethylaminopropenoate
• pyrido[2,3-d]pyrimidine
• nucleoside
• synthesis

Additional information

Funding

This project was supported by Taif University Researchers, Supporting project no. (TURSP-2020/23), Taif University, Taif, Saudia Arabia.