6-Deoxy-allo-nojirimycin in the racemic and d-series, 6-deoxy-d,l-talo-nojirimycin, their 1-deoxyderivatives and 6-deoxy-2-d,l-allosamine via hetero-Diels-Alder cycloadditions
摘要:
Diels-Alder cycloaddition of hexadienal dimethylacetal 3 to achiral acylnitroso-dienophile 5a gave the racemic cycloadducts 7a-c and, to chiral chloronitroso-dienophile 6, enantiomerically pure D-10a as sole adduct. Simple chemical transformations led to 6-deoxy-2-D,L-allosamine 15b, to 6-deoxy-D,L and D-allo-nojirimycin 15a, D-15a, to 6-deoxy-D,L-talo-nojirimycin 15c as well as to their l-deoxy-derivatives 16a, D-16a, 16c via their crystalline l-deoxy-l-sulfonic acid derivatives (sulfite adducts). Amino-sugars 16a,c are mixtures of alpha- and -beta-anomers and of the corresponding imines. (C) 1997 Elsevier Science Ltd.
cycloaddition of sorbic aldehyde derivative 9 and of sorbic acid 10 with the chiral chloro-nitroso dienophile 7 led with excellent regio- and diastereoselectivity to the chiral cycloadducts 11a and 12, respectively. Catalytic osmylation of their Bzl-derivatives 11b and 13b, followed by reductive cleavage of the NO bonds, gave ultimately the chiral aminoallose derivatives D-5 and D-6 which are potential
A straightforward synthesis of (±) 5-amino-5,6-dideoxyallose, of its bisulfite β-anomer, and of its 1-deoxy derivative
作者:Albert Defoin、Hervé Sarazin、Jacques Streith
DOI:10.1016/s0040-4039(00)79341-5
日期:1993.7
Diels-Alder cycloaddition of (E,E)-hexadienal dimethylacetal 3 with the benzyloxycarbonylnitroso dienophile 4, followed by catalytic osmylation, hydrogenolysis, and treatment with SO2, led stereospecifically to the sole beta-anomer of allopiperidinose bisulfite derivative 7. Saponification of 7 and thence catalytic hydrogenation gave in high yield the 1-deoxyallopiperidine derivative 9.