Synthesis and preliminary biological evaluation of 1-aminomethyl-4-substituted-4-H-pyrrolo[2,1-C][1,4] benzothiazines, a new class of calcium antagonists

The preparation of 4a-g, conformationally rigid calcium channel blockers related to Diltiazem, is described starting from tricyclic compounds 5a-c. On radioreceptor assay and preliminary biochemical tests some compounds show high affinity for Calcium Channel Receptors (CCRs) and calcium antagonistic activity comparable or superior to that of Diltiazem.