Synthesis of new pyrrole and pyrrolo[2,3-d]pyrimidine derivatives of potential antioxidant activity

Abstract

New 2-amino-3-cyanopyrrole derivatives were prepared and converted to 7-deazapurines. 7-Deazaadenine 6 was synthesized by different methods and alkylated with alkyl iodides to afford the quaternized 3-alkylpyrrolopyrimidinium iodide salts 8. The latter salts were dequaternized to N-alkylpyrrolo[2,3-d]pyrimidin-4-amines 12. Compounds 12 were identical to the products obtained from reactions of 4-chloro-7-(4-fluorophenyl)-5-p-tolyl-7H-pyrrolo[2,3-d]pyrimidine 11 with methyl- or ethylamine in the presence of a catalyst. The thione 13 and its related 4-methylthio- and 4-ylcarbonothioate derivatives 14a, 14b were obtained. The triazolo- 17a–17e, benzenesulfonamido- 19, and tetrazolopyrrolopyrimidine 21 derivatives were synthesized. Several examples of the synthesized pyrrole- and pyrrolo[2,3-d]pyrimidine derivatives showed high to remarkable antioxidant scavenging activity as measured by their ability to scavenge the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical