title: Synthesis and analgesic properties of new 4-arylhydrazone 1-H pyrazole [3,4-b] pyridine derivatives.
abstract: Based on the principle of bioisosterism, a successful strategy in the planning of new drugs, we describe in this work the synthesis and the analgesic activity of the new functionalized arylcarbaldehyde 4-(1-phenyl-3-methylpyrazolo[3,4-b]pyridine) hydrazone derivatives 5a-m. These derivatives (5a-m) were synthesized in ca. 45% overall yield, using 4-(1-phenyl-3-methylpyrazolo[3,4-b]pyridinyl) hydrazine 6, as key intermediate. by applying classical synthetic methods to construct the aryl-hydrazone unit at C-4 of the heterocyclic system. Compound 6 was prepared from the corresponding 4-chloro-(N-phenyl-3-methylpyrazolo[3,4-b]pyridine) derivative 7 in very high yield. The antinociceptive activity of these new compounds 5a was evaluated by a test of abdominal contortions induced by 0.6% acetic acid solution i.p. in albino mice. The compounds 5f, 5g, 5j and 5k were strongly active showing a good analgesic profile.
authors.affiliation: Programa Deps-Graduaç em quìmicaorgânica, Instituto de Quìmica, Universidade Federaldo Rio de Janeriro, Brazil.
authors.forename: M A
authors.initials: MA
authors.lastname: Gaston
authors.forename: L R
authors.initials: LR
authors.lastname: Dias
authors.forename: A C
authors.initials: AC
authors.lastname: Freitas
authors.lastname: Miranda AlP
authors.forename: E J
authors.initials: EJ
authors.lastname: Barrerio
mesh_terms: D018712:Analgesics, Non-Narcotic / Q000138:chemical synthesis* / Q000494:pharmacology; D000818:Animals; D005260:Female; D006835:Hydrazones / Q000138:chemical synthesis* / Q000494:pharmacology; D008297:Male; D051379:Mice; D010147:Pain Measurement / Q000187:drug effects; D011725:Pyridines / Q000138:chemical synthesis* / Q000494:pharmacology
chemical_list: D018712:Analgesics, Non-Narcotic; D006835:Hydrazones; D011725:Pyridines