Studien zur Chemie von thienoanellierten O,N- und S,N-haltigen Heterocyclen, 8. Synthese eines racemischen, thienoanalogen Diltiazems mit potentieller Calciumkanal blockierender Wirkung

Studies on the Chemistry of Thieno-Annulated O,N- and S,N-Containing Heterocycles, 8[1].–Synthesis of a Racemic, Thieno Analogue Diltiazem with Potential Ca2+Antagonistic Activity The synthesis of the thieno analogue diltiazem cis-8-[2-(di-methylamino)ethyl]-5,6,7,8-tetrahydro-5-(4-methoxyphenyl)-7-oxothieno[3,2-b][1,4]thiazepin-6-yl acetate (1) is described. Reaction of 3-bromo-2-nitrothiophene with Na2S · 9H2O yields the intermediate 3-mercapto-2-nitrothiophene (6), which reacts with the racemic glycidate 7 to give the racemic threo compound 10. Reduction and cyclization of 10 furnish the thieno [3,2-b][1,4]thiazepine derivative 12.N-Alkylation and acetylation of the hydroxy group of 12 leads to 1.