SUBSTITUTED PYRIDINIUM-3-SULFONAMIDATES A ND PYRIDO[3,4-B]INDOLES FROM ,5-DIMETHYL-1,1-DIOXO-1,2-THIAZINE-6-CARBALDEHYDES AND AMINES

Due to their masked 1,5-dicarbonyle structure, 1,2-thiazine-6-carbalde hydes (1) undergo a ring transformation with aliphatic amines and diam ines to give substituted pyridinium-3-sulfonamidates 2-6 and bis-(pyri dinium-3-sulfonamidates) 7-9, respectively. With bioactive beta-substi tuted ethylamines, pyridinium derivatives 12-20 with potential biologi cal activity were obtained. Under acidic conditions, the thiazine-6-ca rbaldehydes 1a-d react with tryptamine to give substituted 9H-tetrahyd ropyrido[3,4-b]indoles 22a-d (Harman type alcaloids). 22a was dehydrog enated to the corresponding pyrido-indole 23a by palladium coal.