6,16-methano-6H,16H-[2,4]benzothiazepino[3,4-d][1,3,5]benzoxa-diazocine and 6,26 : 13,19-dimethano-6H,9H,13H,19H, 22H,26H-benzo[1 '',2 '': 5,6;4 ''',5 '': 5 ',6 ']bis[1,3] thiazepino[2,3-d : 2 ',3 '-d]bis[1,3,5]-benzoxadiazocine: New heterocyclic systems

Cyclization reactions of oxygen-bridged pyrimidinethione 1a with 1,2-bis(br omomethyl)benzene and 1,2,4,5-tetrakis(bromomethyl)benzene leading to confo rmationally restricted benzothiazepine derivatives were examined. Molecular conformations of the products were studied by 1D and 2D nmr spectroscopy a nd with the help of semiempirical calculations.