Process for preparing optically active benzothiazepine compounds by asymmetric reduction
AssigneeTanabe Seiyaku Co., Ltd.
InventorsYasuhiko Ozaki, Shinichi Yamada, Hiroyasu Seko
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Abstract
Process for preparing optically active cis-3-hydroxy-2,3-dihydro-1,5-benzothiazepin-4(5H)-one compounds [I] of the formula: ##STR1## wherein Ring A and Ring B are substituted or unsubstituted benzene, R.sup.1 is hydrogen or di-lower alkylaminoalkyl, which comprises subjecting 1,5-benzothiazepin-4(5H)-one (II) of the formula [II]: ##STR2## wherein R.sup.4 is hydrogen or lower alkanoyl, and the other symbols are the same as defined above, to asymmetric reduction with a reaction product of optically active .alpha.-amino acid and metal hydride, in high optically yield, and said compounds [I] are very important as intermediate for preparing various medicines.
Claims9
A process for preparing an optically active cis-3-hydroxy-2-phenyl-2,3-dihydro-1,5-benzothiazepine compound of the formula (I):
- ##STR12## wherein Ring A and Ring B are each an unsubstituted benzene ring or a benzene ring substituted by a substituent selected from the group consisting of a lower alkyl group, a lower alkoxy group and a halogen atom, R.sub.1 is a hydrogen atom or a group of the formula:
- ##STR13## wherein R.sub.2 and R.sub.3 are the same or different and a lower alkyl group or a lower alkoxy-substituted-phenyl lower alkyl group, and Q is a lower alkylene group, which process comprises subjecting a 2-phenyl-1,5-benzothiazepin-4(5H)-one compound of the formula (II):
- ##STR14## wherein R.sup.4 is a hydrogen atom or a lower alkanoyl group, and R.sup.1, Ring A and Ring B are the same as defined above, to asymmetric reduction with a reaction product of an optically active .alpha.-amino acid and a metal hydride.
A process for preparing an optically active cis-3-hydroxy-2-phenyl-2,3-dihydro-1,5-benzothiazepin-4(5H)-one compound of the formula (I):
- ##STR15## wherein Ring A and Ring B are each an unsubstituted benzene ring or a benzene ring substituted by a substituent selected from the group consisting of a lower alkyl group, a lower alkoxy group and a halogen atom, and R.sub.1 is a hydrogen atom or a group of the formula:
- ##STR16## wherein R.sub.2 and R.sub.3 are the same or different and a lower alkyl group or a lower alkoxy-substituted phenyl-lower alkyl group, and Q is a lower alkylene group, which process comprises subjecting a 2-phenyl-1,5-benzothiazepine-3,4(2H,5H)-dione compound of the formula (II-a):
- ##STR17## wherein Ring A, Ring B and R.sup.1 are the same as defined above, to asymmetric reduction with a reaction product of an optically active .alpha.-amino acid and a metal hydride.
Dependencies are inferred from the claim text.