Synthesis of pyranopyrazolo N-glycoside and pyrazolopyranopyrimidine C-glycoside derivatives as promising antitumor and antimicrobial agents

As a part of systematic investigation of the synthesis and biological activities of pyrazole analogues linked to various heterocyclic systems, a new series of pyrazolo-N-glycoside derivatives, pyrazolopyranopyrimidine and C-glycoside of pyrazolopyranotriazolo-pyrimidine derivatives was synthesized through the reaction of the key intermediate 6-amino-3-methyl-4-(substituted-phenyl)-1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile (3a,b) with different reagents. Structures of the newly synthesized compounds were elucidated by elemental microanalysis and spectroscopic methods. The compounds were subjected to in vitro antitumor evaluation using the MTT assay. N-(β-D-ribofuranosyl)- and N-(β-D-xylofuranosyl)-6{[(1E)-4-chlorophenyl)-methylene] amino}4-(4-florophenyl)-3-methyl-1,4-dihydropyrano[2,3-c]-pyrazole-5-carbonitrile (6a,b) were the most active compounds against three human cancer cell lines. Also, most of the newly synthesized compounds exhibited high activity towards Gram-negative and Gram-positive bacteria. Compound 6a exhibited excellent activity towards bacteria compared to ofloxacine as the reference drug.