A Semisynthesis of Dehydrocorydaline From Palmatine

This paper describes a method for semisvnthesis of dehydrocorydaline (1)-a drug used for peptic ulcer. This method is similar to that of semisynthesis of 13-methyl-berberine. First, under concentrated alkaline medium the acetonepalmatine was obtained. Then acetonepalmatine reacted with methyliodide in sealed tube to give dehydrocorydaline iodide (33% yield), and converted to its chloride by ordinary method. So the synthesis of dehydrocorydaline from palmatine is very convenient and economical.