The synthesis and the nuclear magnetic resonance study of β-lactam derivatives of 1,5-benzothiazepines
Keyword(s):
The synthesis and stereochemistry of seven β-lactam derivatives of 1,5-benzothiazepines are presented. The configurational and conformational analysis is based on nuclear Overhauser effect experiments, together with analysis of the vicinal proton–proton coupling constants. In the preferred conformation, the seven-membered ring is in a half-chair. Only for one compound, 2-aza-4-bromo-4-methyl-5,7-diphenyl-8-thiatricyclo[7.4.0.02,5]trideca-Δ1,9,10,12-trien-3-one, were two diastereomers isolated (compounds 6a and 6b). Six of the compounds have the 4S*, 5R*, 7R* configuration while compound 6b has the 4R*, 5R*,7R* configuration.
1988 ◽
Vol 53
(11)
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pp. 2503-2510
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1993 ◽
Vol 206
(1-4)
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pp. 253-259
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1999 ◽
Vol 314
(1-2)
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pp. 168-175
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1980 ◽
Vol 35
(3)
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pp. 282-296
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1984 ◽
Vol 22
(6)
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pp. 385-387
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