BENZOPYRANS, METHOD OF PREPARATION THEREOF, INTERMEDIATE COMPOUNDS AND PHARMACEUTICAL COMPOSITIONS Russian patent published in 2000 - IPC

FIELD: pharmaceutical industry. SUBSTANCE: described are new benzopyrans of formula I: wherein R₁ is phenyl, methoxyphenyl, fluorophenyl or pyridyl, trifluoromethyl phenyl; R₂ is H or C_1-5 alkyl, or C_2-5 alkylene bonded with с R₁; R₃ is group of formula: -N(R₉)2COR₁₀ wherein R₉ is hydrogen, and R₁₀ is phenyl or pyridyl, or R₉ and R₁₀ are together 1,3-butadienylene or group of formula (CH₂)_n, wherein n is integer of 3 to 5 inclusive; R₄ is hydrogen and R₅ is hydroxy in trans-position with respect to R₃; or R₄ and R₅ together are additional bond as denoted by dotted line, R₆ and R₇ are independently C_1-5 alkyl, and R₈ is hydrogen, or physiologically hydrolyzable and physiologically acceptable ester of said compound or acid addition salt or quaternary ammonium salt of said compound or ester. Also described are method of preparation thereof, intermediate compounds and pharmaceutical compositions that open K channels, broncholytic agents and agents for suppressing hyperreactivity of respiratory tract, e.g. in treating asthma. EFFECT: improved properties of the title compounds. 7 cl, 1 tbl