作者: S. A. BARKER , J. S. BRIMACOMBE , M. J. HOW , M. STACEY , J. M. WILLIAMS
DOI: 10.1038/189303A0
关键词: Polysaccharide 、 Hydrolysis 、 Hydrolysate 、 Methanol 、 Hydrochloride 、 Residue (chemistry) 、 Phosphorus pentoxide 、 Medicinal chemistry 、 Chemistry 、 Hydrochloric acid
摘要: THOUGH a large number of antigenic capsular polysaccharides Pneumococcus are known to contain one or more amino-sugars1, in only case, namely, 2-amino-2-deoxy-D-glucose (D-glucosamine) from type XIV polysaccharide2, has the amino-sugar been isolated and characterized. Two amino-sugars, designated ‘pneumosamine’ ‘amino-sugar X’ have purified Type V polysaccharide3, preliminary investigations, which included analysis crystalline N-acetamido alcohol derivatives, indicated that both sugars were 2-amino-2,6-dideoxyhexoses. Kuhn-Roth determinations on ‘N-acetylpneumosaminol’ (1.52 moles CH3) (0.68 mole support postulated 6-deoxyhexosamine structure. The now tentatively identified as 2-amino-2,6-dideoxytalose (pneumosamine) 2-amino-2,6-dideoxy-L-galactose (amino-sugar X). polysaccharide hydrolysate (hydrolysis conditions: 2 N hydrochloric acid, 24 hr., 100°) by chromatography ‘Dowex-50’ resin4. acidic effluents neutralized with ‘Deacidite FF’ (carbonate form), lyophilized syrupy residues dried vacuo over phosphorus pentoxide. Treatment residue methanol gave ‘pneumosamine hydrochloride’ melting point 162–3° (from methanol–ether); [α]18 D + 6.9° (10 min.), → 10.4° equil. (cone. 2.3 water). Found: C, 35.9; H, 7.4 per cent; calc. for C6H14O4NCl: 36.1; 7.1 cent. ‘Amino-sugar was crystallized water–methanol–acetone mixture.