Murata H, Harada K, Suzuki M, Ikemoto T, Shibuya T, Haneishi T, Torikata A
Faculty of Pharmacy, Meijo University, Nagoya, Japan.
J Antibiot (Tokyo). 1989 May;42(5):701-10. doi: 10.7164/antibiotics.42.701.
Treatment of aculeximycin with 2% 1,8-diazabicyclo[5,4,0]undecene-7 (DBU)-methanol yielded three products, aculexitriose, pseudoaglycones I and II. The structural elucidation of aculexitriose was carried out by spectral analyses (MS, NMR (1H-1H 2D NMR spectroscopy, nuclear Overhauser effect] and chemical degradations of aculexitriose and its derivatives. The structure of aculexitriose was established to be a branched trisaccharide, O-6-deoxy-beta-D-glucopyranosyl-(1----2)-O-[3-amino-2,3,6-trideoxy-beta- D- arabino-hexopyranosyl-(1----3)]-6-deoxy-D-glucopyranose. On the other hand the pseudoaglycones I and II were stereoisomers with respect to a chiral center newly formed by the DBU reaction. The pseudoaglycones contain one neutral sugar and one amino sugar, which turned out to be D-mannose and L-vancosamine, respectively.
用2%的1,8 - 二氮杂双环[5,4,0]十一碳 - 7 - 烯（DBU） - 甲醇处理阿库列西霉素得到三种产物，阿库列三糖、假苷元I和II。通过光谱分析（质谱、核磁共振（1H - 1H二维核磁共振光谱、核Overhauser效应）以及阿库列三糖及其衍生物的化学降解对阿库列三糖的结构进行了阐明。阿库列三糖的结构被确定为一种分支三糖，即O - 6 - 脱氧 - β - D - 吡喃葡萄糖基 - (1→2) - O - [3 - 氨基 - 2,3,6 - 三脱氧 - β - D - 阿拉伯吡喃己糖基 - (1→3)] - 6 - 脱氧 - D - 吡喃葡萄糖。另一方面，假苷元I和II是关于由DBU反应新形成的一个手性中心的立体异构体。假苷元含有一个中性糖和一个氨基糖，结果分别为D - 甘露糖和L - 万古糖胺。
