Glycosylidene Carbenes. Part 5. Synthesis of Glycono-1,5-lactone Tosylhydrazones as Precursors of Glycosylidene Carbenes
作者:Sissi E. Mangholz、Andrea Vaseha
DOI:10.1002/hlca.19910740845
日期:1991.12.11
only. Yields and ratios of products were compared to those obtained with the diazirine 1 as a source of glycosylidene carbenes. While the yields from 20 are lower, the ratios of products obtained in the photolytic reactions are in agreement with the formation of a common intermediate from both carbene precursors.
的苄基和酰基保护glyconolactone甲苯磺酰腙6,9,12,16,和19(方案1)通过处理所述半缩醛以良好的收率制备4,7,10,14,和17与Ñ -tosylhydrazine,得到所述ñ -glycosylhydrazines 5,8,11,15,和18,并通过与氧化这些hydraz尝试ñ-溴代琥珀酰亚胺(NBS)在1,8-二氮杂双环[5.4.0]十一碳-7-烯(DBU)的存在下,与CrO 3-二吡啶配合物或重铬酸吡啶鎓存在。在N-苯基马来酰亚胺,富马酸二甲酯或丙烯腈的存在下,对6(方案2)的钠帆20进行光解,可以令人满意的收率得到相应的环丙烷21 – 28。Phololytic或苯酚和由4- melhoxyphenol的热分解苷化20,得到端基异构苷29日/ 30和31 / 32,在等温分解过程中的收率略高。丙-2-醇的光解糖基化仅以低产率得到糖苷33和34。将产物的收率和比