Takeda T, Kanemitsu T, Shimizu N, Ogihara Y, Matsubara M
Kyoritsu College of Pharmacy, Tokyo, Japan.
Carbohydr Res. 1996 Mar 22;283:81-93. doi: 10.1016/0008-6215(96)00004-3.
A stereo-controlled synthesis of the model compound for the phytoalexin elicitor-active glycoprotein is described. Glycosylation of the trisaccharide, 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl-(1-->6)-2,3,4-tri-O-acetyl- alpha-D-mannopyranosyl-(1-->6)-2,3,4-tri-O-acetyl-alpha-D-mannopyranosyl trichloroacetimidate (12), with N-(9-fluorenylmethoxycarbonyl)-L-seryl-L- proline benzyl ester (3) or N-(carbobenzoxy)-L-seryl-L-proline methyl ester (4) by use of BF3. OEt2 gave the triglycosyl-seryl-proline derivatives. The N- as well as C-terminus of these triglycosyl dipeptides could be deblocked selectively to give compounds 14 and 16, which are versatile intermediates for the completion of model compound synthesis of glycopeptide. Triglycosyl tetrapeptides (18, 21) and hexaglycosyl tetrapeptide (23) have been prepared by the convergent block synthesis.
描述了植物抗毒素诱导活性糖蛋白模型化合物的立体控制合成。三糖2,3,4,6-四-O-乙酰基-β-D-吡喃葡萄糖基-(1→6)-2,3,4-三-O-乙酰基-α-D-甘露吡喃糖基-(1→6)-2,3,4-三-O-乙酰基-α-D-甘露吡喃糖基三氯乙酰亚胺酯（12）与N-(9-芴甲氧羰基)-L-丝氨酰-L-脯氨酸苄酯（3）或N-(苄氧羰基)-L-丝氨酰-L-脯氨酸甲酯（4），使用BF₃·Et₂O进行糖基化反应，得到三糖基-丝氨酰-脯氨酸衍生物。这些三糖基二肽的N-端和C-端可以选择性地脱保护，得到化合物14和16，它们是用于完成糖肽模型化合物合成的通用中间体。通过汇聚式片段合成法制备了三糖基四肽（18, 21）和六糖基四肽（23）。
