Copper(II)‐Mediated Activation of Sugar Oxazolines: Mild and Efficient Synthesis of β‐Glycosides of
<i>N</i>
‐Acetylglucosamine
作者:Valentin Wittmann、Dirk Lennartz
DOI:10.1002/1099-0690(200204)2002:8<1363::aid-ejoc1363>3.0.co;2-#
日期:2002.4
2-Methyl-(3,4,6-tri-O-acetyl-1,2-dideoxy-α-D-glucopyrano)[2,1-d]-2-oxazoline (5) was reacted with glycosyl acceptors bearing primary (6, 8, 10, 20) or secondary hydroxy groups (12, 14, 16, 18) in the presence of anhydrous cupric bromide or cupric chloride at elevated temperature to provide 2-acetamido-2-deoxy-β-D-glucopyranosides in 36−92% yield. The reaction conditions are milder than those previously
使2-甲基-(3,4,6-三-O-乙酰基-1,2-二脱氧-α-D-吡喃吡喃)[2,1 - d ] -2-恶唑啉(5)与带有伯基的糖基受体反应(6,8,10,20)或仲羟基基团(12,14,16,18)在无水溴化铜或氯化铜的存在下,在升高的温度,以提供2-乙酰氨基-2-脱氧-3-β-d-吡喃葡萄糖苷收率为36-92%。该反应条件比以前描述的使用p进行恶唑啉活化的条件温和-甲苯磺酸或氯化铁。用三甲基硅烷基叠氮化物(22)和CuCl 2处理恶唑啉可产生2-乙酰氨基-3,4,6-三-O-乙酰基-2-脱氧-β-D-吡喃葡萄糖基叠氮化物(23),产率为69%。(©Wiley-VCH Verlag GmbH,69451 Weinheim,Germany,2002)