An improved synthesis of the 5-deoxy-5-(
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Thomas Richter; Peter Luger; Tadashi Hanaya; Hiroshi Yamamoto
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Article
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1989
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Elsevier Science
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English
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Treatment of 3-0-acetyl-5-deoxy-5-(dimethoxyphosphinyl)-l,2-O-isopropylidene-cr-D-glucofuranose (7) with dihydropyran in the presence of pyridinium ptoluenesulfonate gave the 6-0-(tetrahydropyran-2-yl) derivative in 91% yield. Ring-enlargement of this compound by the known, 2-step procedure gave 5-d