The work is devoted to study synthesis of 1H-pyrazolo[3,4-b]pyridin-3(2H)-ones with potential biological activity. 1H-pyrazolo[3,4-b]pyridin-3(2H)-one derived moieties were afforded using classical approaches involving [3+3] cyclocondensation of enamine fragment-containing heterocycle and bielectrophiles, inverse electron-demand Diels-Alder reaction, palladium-catalyzed C-C coupling reaction. N-nucleosides of purine analogues were synthesized using modified silyl Hilbert-Jones method. Scope and limitations of hydrogenation of pyridine ring of 1H-pyrazolo[3,4-b]pyridin-3(2H)-ones were studied.