Synthetic approach to rhoeadine-type alkaloids
Abstract
The reaction of 3,4-dihydropapaveraldine [1-(3,4-dimethoxybenzoyl)-3,4-dihydro-6,7-dimethoxyisoquinoline] methiodide (2) with diazomethane gave 5-(3,4-dimethoxybenzoyl)-2,3-dihydro-7,8-dimethoxy-3-methyl-1H-3-benzazepine (5), which was converted into 5,6,7,7a-tetrahydro-2,3,9,10-tetramethoxy-7-methylindeno-[2,1-a][3]benzazepin-12-ol (3) with hot phosphoryl chloride.