Synthesis of new compounds containing the pyrazolo[3,4‐b]pyridine‐3‐one subunit

Abstract

in Wiley InterScience (www.interscience.wiley.com).A convenient route for the synthesis of pyrazolo [3,4-b]pyridine-3-ones via condensation of 3-amino-1-phenylpyrazolin-5-one with 4-hydroxy-6-methylpyran-2-one is described. The pyrazolo[3,4-b]pyridine-3-one isomers obtained were functionalized at 1-, 4-, or 6-position by different pharmacophore entities allowing the synthesis of new compounds with promising biological activities.

Synthesis and Anti-Inflammatory Activity of N(2)-Arylindazol-3(2H)-One Derivatives: Copper-Promoted Direct N-Arylation via Chan–Evans–Lam Coupling

“…Well-known deprotection of the PMB group using TFA (trifluoroacetic acid) was adopted. N (1)-PMB- N (2)-aryl-substituted indazol-3-one 7 underwent successful deprotection in just one hour under TFA conditions ( Scheme 3 , Method B) [ 26 ]. Most of the derivatives, including those that had previously generated low yields with the benzyl-protecting group, were synthesized in very high yields using this method.…”

An easy synthetic access to new pyrazole spiro derivatives from 3-amino-1-phenyl-2-pyrazolin-5-one

“…16 In this context, we have been intensively investigating the preparation of pyrazolo [3,4-b]pyridines (3 and 4), through the condensation of 3-amino-1-phenyl-2-pyrazolin-5-one 1 with 4hydroxy-6-methylpyran-2-one 2 (Scheme 1). [17][18][19] Scheme 1 Synthetic route to pyrazolo [3,4-b]pyridines from condensation of 3-amino-1-phenyl-2-pyrazolin-5-one 1 with 4-hydroxy-6-methylpyran-2-one 2…”

“…16 In this context, we have been intensively investigating the preparation of pyrazolo [3,4-b]pyridines (3 and 4), through the condensation of 3-amino-1-phenyl-2-pyrazolin-5-one 1 with 4-hydroxy-6-methylpyran-2-one 2 (Scheme 1). [17][18][19] Following our research interest in exploring the commercially available synthon 1 for preparing new heterocycles, we decided to evaluate its reactivity with aromatic aldehydes under Knoevenagel conditions to obtain new a,b-unsaturated carbonyl compounds. Noteworthy, T. R. Sobahi isolated pyranodipyrazole derivatives in moderate yields (53-61%) by reacting 1 with different aromatic aldehydes in the absence of solvent, and heating the reaction mixture at 160-170 1C (via a, Scheme 2, compound I was obtained using benzaldehyde).…”