METHOD FOR PRODUCING SULPHOCHLORIDES OF 6-ARYLPYRIDAZINE-3(2H)-ONES Russian patent published in 2012 - IPC A61K31/50 C07D237/04 C07D237/14 C07D237/18 

FIELD: medicine, pharmaceutics.

SUBSTANCE: invention refers to organic chemistry and pharmaceutics and concerns an improved method for producing sulphochloride derivatives of 6-arylpyridazine-3(2H)-ones of general formula VIII from the related 6-aryl-4,5-dihydropyridazine-3(2H)-ones of general formula VII by the reaction thereof and chlorosulphonic acid at temperature 0-5°C that is followed by the reaction initially at 20-50°C for 1-4 hours, and then at temperature 90-140°C; thereafter the reaction mixture is kept at the same temperature for 3-4 hours with mixing.

EFFECT: method provides higher product yield and purity degree.

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