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[摘要]：Oxidation of enantiomerically pure (R)-N(1)-1`-(1 ''-naphthyl)ethyl-2,7dihydro-1H-azepine with m-CPBA in the presence of HBF4 and BnOH gave (3S,4R,5S,6S, 1`R)-N(1)-1`-(1 ''-naphthyl)ethyl-3-hydroxy-4-benzyloxy-5,6-epoxyazepane as the major product and as a single diastereoisomer after chromatography. Elaboration of this highly functionalized intermediate via ring contraction to (2S,3R,4S,5S,1`R)-N(1)-benzyl-2-chloromethyl-3-benzyloxy-4,5-epoxypiperi dine followed by regioselective epoxide ring opening, functional group manipulation, and deprotection gave (+)-1-deoxyaltronojirimycin. Alternatively, resolution of (RS,RS)-N(1)-benzyl-3-hydroxy-4-benzyloxy-2,3,4,7-tetrahydro-1H-azepine or (3RS,4SR,5RS,6RS)-N(1)-benzyl-3-hydroxy-4-benzyloxy-5,6-epoxyazepane by preparative chiral HPLC and subsequent elaboration allows access to the enantiomers of 1-deoxynojirimycin and 1-deoxyaltronojirimycin, respectively. |
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