BENZOPYRAN DERIVATIVES OR THEIR PHARMACEUTICALLY ACCEPTABLE SALTS, AND A METHOD OF THEIR SYNTHESIS Russian patent published in 1995 - IPC

FIELD: organic chemistry. SUBSTANCE: product: derivatives of benzopyran of the formula (I) where R¹, R², α-β, R³ and R⁴ have corresponding meanings. Reagent 1: compound of the formula (IV) where a) W W-NH₂--group; W′-OH- OH-group or b) W and W′ together with oxygen atom form ethoxy-group. Reagent 2: in the case of a) compound of the formula (V) where R⁴ as indicated above; R⁶ C₁-C₄-alkyl; R⁷ formyl or haloidmethyl, or in the case of b) compound of the formula (VI) or (VIa) where R⁴ and R⁵ as indicated above; Q -α-γ- represents a group of the formula (VII) or (VIII) where R^8a, R^8b and R^8c C₁-C₄--alkyl, and compound of the formula (Ia) is synthesized where R¹ and R² as indicated above. If necessary, compound of the formula (Ia) is treated with base, and compound of the formula (Ib) is prepared where R¹ and R² as indicated above, or, if necessary, compound of the formula (Ia) is interacted with nitrating reagent, and compound of the formula (Ic) is prepared where R¹ and R² as indicated above, or, if necessary, compounds of the formulas (Ia) (Ib) and (Ic) were isolated in the form of pharmaceutically acceptable salt. Realative activity of synthesized compounds as compared with cromacalim is 17-64% Synthesized compounds were used in medicine. EFFECT: improved method of synthesis. 4 cl, 3 tbl