Short and Efficient Syntheses of Gabosine I, Streptol, 7-O-Acetylstreptol, 1-epi-Streptol, Gabosine K, and Carba-α-d-glucose from δ-d-Gluconolactone
作者:Tony Shing、Y. Chen、W. Ng
DOI:10.1055/s-0030-1260547
日期:2011.6
gabosine 1 (five steps with 65% overall yield from δ-D-gluconolactone), streptol (six steps, 54% overall yield), 7-O-acetyl-streptol (seven steps, 42% overall yield), 1-epi-streptol (six steps, 49% overall yield), gabosine K (seven steps, 40% overall yield), and carba-α-D-glucopyranose (seven steps, 47% overall yield). The present chemical syntheses, from commercially available δ-D-gluconolactone, provide
δ-D-葡萄糖酸内酯在四步中被碳环化为 EOM 保护的环己烯酮,包括过乙氧基甲基化、膦酸阴离子加成、还原和氧化,同时伴随着 Horner-Wadsworth-Emmons 烯化。稳定的关键烯酮被有效地转化为 gabosine 1(五步,δ-D-葡萄糖酸内酯的总产率为 65%)、链霉醇(六步,总产率 54%)、7-O-乙酰-链醇(七步,42%总产率)、1-表链糖醇(六步,总产率 49%)、加波辛 K(七步,总产率 40%)和卡巴-α-D-吡喃葡萄糖(七步,总产率 47%)。目前的化学合成,从市售的 δ-D-葡萄糖酸内酯,提供了迄今为止这些分子的最高总产率。