A synthesis of 6-functionalized 7-unsubstituted- and 7-methyl[1,2,4]azolo[1,5-a]pyrimidine derivatives

Abstract

6-Functionalized 7-R-4,7-dihydro[1,2,4]azolo[1,5-a]pyrimidines (R = H or Me) were synthesized by Biginelli-like reaction of formaldehyde or acetaldehyde, aminoazoles, and corresponding β-dicarbonyl precursor. Alkylation of the obtained compounds proceeds smoothly at position 4, while oxidation leads to 7-R-[1,2,4]azolo[1,5-a]pyrimidines formation. 6-Ethoxycarbonyl derivatives could be reduced to the corresponding alcohols by LiAlH₄ and hydrolyzed to the acids.

GRAPHICAL ABSTRACT

KEYWORDS:

• Alkylation
• Biginelli-like reaction
• building blocks
• oxidation
• reduction
• 4,7-dihydro[1,2,4]azolo[1,5-a]pyrimidines

Acknowledgments

We thank V. I. Musatov, V. V. Vashchenko, E. V. Vashchenko (STC “Institute for Single Crystals” NAS of Ukraine) and Enamine Ltd. for spectroscopic measurements and A. Yu. Lyapunov (A. V. Bogatsky Physico-Chemical Institute NAS of Ukraine) for fruitful discussion.

Additional information

Funding

This work was supported by V. N. Karazin Kharkiv National University under Grant 811н/12-17.