METHOD OF SYNTHESIS OF PYRAZOLOPYRIMIDINE COMPOUNDS OR THEIR PHARMACEUTICALLY ACCEPTABLE SALTS Russian patent published in 1995 - IPC

FIELD: organic chemistry. SUBSTANCE: product: compounds of the formula (I) where R¹ hydrogen, methyl or ethyl; R² methyl, CH₂OH, CH₂-OCH₃ or n-propyl; R³ ethyl, propyl, allyl; R⁴ together with nitrogen with which it is bound forms 4-N-(R⁶)-piperazinyl group; R⁵ hydrogen and others; R⁶ hydrogen and others, or their pharmaceutically acceptable salts. Reagent 1: compounds of the formula (II) where Y chlorine, bromine and others. Reagent 2: compounds of the formula (III). Reaction conditions: after interaction of reagents 1 and 2 the end product is isolated or converted to the pharmaceutically acceptable form, or phenolic group is O-alkylated, or if R² hydroxy-group then it is protected with acetyl or benzoyl group followed by its removal by hydrolysis. Synthesized compounds were used in pharmacology. EFFECT: improved method of synthesis. 2 tbl