Synthesis of all four stereoisomers of 5-formyl-4-hydroxymethyl-1,3-oxazolidin-2-ones from d-glucosamine
作者:Teiichi Murakami
DOI:10.1016/j.carres.2013.04.021
日期:2013.6
3-oxazolidin-2-ones (FHOs) were conveniently prepared from D-glucosamine by base-catalyzed epimerizations. 2-N,3-O-Carbonyl-D-glucosamine (7) was successively treated with NaBH4 and NaIO4 to give (4S,5R)-FHO 18, which was epimerized with DBU in DMF to give (4S,5S)-FHO 20. The glucosamine derivative 7 was epimerized to 2-N,3-O-carbonyl-D-mannosamine 23, from which (4R,5R)- and (4R,5S)-FHO derivatives (27 and
5-甲酰基-4-羟甲基-1,3-恶唑烷基-2-酮(FHOs)的所有四个立体异构体都可以通过D-葡萄糖胺通过碱催化的差向异构化方便地制备。用NaBH4和NaIO4依次处理2-N,3-O-羰基-D-葡萄糖胺(7)得到(4S,5R)-FHO 18,在DMF中用DBU差向异构化得到(4S,5S)-FHO 20.将葡糖胺衍生物7差向异构化为2-N,3-O-羰基-D-甘露糖胺23,由此制备了(4R,5R)-和(4R,5S)-FHO衍生物(27和31)。NMR测量表明,4,5-顺4(或5)-甲酰基-5(或4)-羟甲基-恶唑烷酮衍生物形成五元内酯环,而4,5-反式-二取代衍生物形成水合物。或开链醛的甲醇加合物或对称的二聚体。