bMe2 OBn 80 81 0 Reagents: i. AgC104, rnolec. '66 In the field of uronic acid disaccharides, enzymic digestion of heparin gave the unsaturated disaccharide 83,'67 and the related compound 84, named lepidimoide, which has been isolated from germinating cress seeds, promotes shoot growth and inhibits root growth. 168 The artificial 2-acetamido-2-deoxy-~-D-mannuronic acid- kv 36 Carbohydrate Chemistry CHzOH O O G OH O OH H OH 0 OH NHAC 84 83 containing glycolipid 85, which corresponds to the repeating unit of a teichuronic acid from 85 Micrococcus luteus, has been synthesized.
T. Knerr and T. , 1993, 34, 7389. R. -Unters. 195, 112 (Chem. , 1993, 118, 123 219). * A review in Japanese has dealt with thioglycosides as glycosylating agents? ~Much interesting chemistry is dealt with in detail. 6 An ingenious new approach has been reported by Schmidt which involves the synthesis of the orthcester intermediates 1 and their collapse to give fl-glucosides with anomeric Ph 1 Reagents: i, NaH. crown ether, RCHz OTf scheme 2 OBn 3: Glycosides and Disaccharides 15 selectivity 8: l(Scheme 2).
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