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The structure of Saccharomyces cerevisiae (commercial baker's yeast) mannan has been reported by many investigators. [2][3][4][5][6][7][8] It is highly branched and contains 1→2, 1→3, and 1→ 6 linkages. Mannan has been proposed to have a "backbone" of 1→ 6-linked mannose units with 1→2-and 1→3-linked side chains that average about two sugar units in length. [6][7][8] Stewart and Ballou,8) while not offering any particular ratio or order of units in the chain, have suggested that the mannan from S. cerevisiae has a structure like that depicted in Fig. 1. NMR spectra of mannans have been analyzed, [9][10][11][12] and recently Vinogradov et al. 13) have deduced the complete structure of mannan and assessed the ratio of different side chains on the basis of high-field NMR spectroscopy data.Thus far, the deacetylated products of an acetolysate of yeast mannan have been separated by gel filtration, and the structures of each, along with the branch point of linkage, have been mainly established by methylation analysis. Although structural analyses of oligosaccharides of the polysaccharide mannan and mannoprotein using NMR spectroscopy have been performed, 9-13) pure oligosaccharides could rarely be obtained.We have chemically synthesized the branched cyclodextrins glucosyl-cyclodextrins 14,15) and galactosyl-cyclodextrins 16) and are now trying to synthesize branched cyclodextrins with mannose on the nonreducing ends in their side chains, because such compounds are expected to be useful as drug carriers in targeted drug delivery systems. To obtain the pure manno-oligosaccharides as side chains, we tried to isolate them from S. cerevisiae by isolating acetolysis fragments. Using an aminopropyl-silica column, the products were completely isolated as mannobiose (M 2 ), mannotrioses (M 3 s), and mannotetraose (M 4 ). Also, using a graphitized carbon column (GCC), two isomers of M 3 s, M 3 -1 and M 3 -2, were obtained. Their structures were elucidated by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and NMR spectroscopy. ExperimentalHPLC Conditions HPLC analyses were performed with a Jasco 980-PU pump and a Shodex RI-71 monitor. The columns used were a Hibar LiChroCART NH 2 (250ϫ4.0 mm i.d., Kanto Chemical) and a Hypercarb (5 mm, 100ϫ4.6 mm i.d., Thermo Hypersil). For preparative HPLC, a TSKgel Amide-80 column (300ϫ21.5 mm i.d., Tosoh) and a Hypercarb (5 mm, 100ϫ10 mm i.d., Thermo Hypersil) were used. HPLC analyses at constant temperature were conducted using a column oven .MS MALDI-TOF-MS was performed in the positive-ion mode on a Vision 2000 reflector-type TOF instrument (Thermo Bioanalysis). The other conditions for measurements were as reported in a previous paper. H correlation spectroscopy (COSY) and 1 H-13 C COSY measurements were as reported in a previous paper. 18)Isolation of Mannan Pressed baker's yeast (2.0 kg) was crumbled into 900 ml of water and 90 ml of 0.2 M citrate buffer solution (pH 7.0), and the mixture was autoclaved at 125°C for 2 h. Crude mannan (30.0...

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Twenty seven diabetic patients, accompanied with ophthalmoplegia , who visited the Dept. of Ophthalmology of Saiseikai Central Hospital over the period between September 1980 and August , 1988 were retrospectively studied. The age of onset of ophthalmoplegia ranged from 36 to 78 y. o. (Av, 65.1 y. o.) and 21 out of 27 were of the age more than 60 y. o. The abducens was involved in 14 cases , the oculomotor 10 cases