Synthesis and Reactivity of Halogenated 1,2,4-Triazole Nucleoside Analogues with High Potential for Chemical Modifications
作者:Ralf Miethchen、Stefanie Libnow、Susanne Wille、Andrea Christiansen、Martin Hein、Helmut Reinke、Martin Köckerling
DOI:10.1055/s-2006-926281
日期:——
1,2,4-Triazole nucleoside analogues bonded at N-1 of the base were synthesized by addition of N-halo-3,5-dibromo-1,2,4-triazoles to 1,2-unsaturated carbohydrate derivatives (glycals). Examples are given for 1,5-anhydro-3,4,6-tri-O-acetyl-2-deoxy-d-arabino-hex-1-enitol (tri-O-acetyl-d-glucal), and 1,5-anhydro-3,4,6-tri-O-benzyl-2-deoxy-d-arabino-hex-1-enitol (tri-O-benzyl-d-glucal), respectively. The graduated reactivity of the three halogens [C-5 (triazole) > C-2 (sugar) > C-3 (triazole)] in the addition products allows subsequent regioselective replacement and deprotection reactions like hydrodehalogenations, nucleophilic substitutions (by methoxide, hydrazine, benzylamine, thiophenolate), deacetylations, and debenzylations, respectively. Thus, the paper opens a new synthetic approach to triazole nucleoside analogues of 2-deoxy-sugars. X-ray analyses support the structures of nine products.
通过将 N-卤代-3,5-二溴-1,2,4-三唑加成到 1,2-不饱和碳水化合物衍生物(甘油)上,合成了键合在碱基 N-1 处的 1,2,4-三唑核苷类似物。给出了1,5-脱水-3,4,6-三-O-乙酰基-2-脱氧-d-阿拉伯-己-1-烯醇(三-O-乙酰基-d-葡糖)的实例,和1,分别为5-脱水-3,4,6-三-O-苄基-2-脱氧-d-阿拉伯-己-1-烯醇(三-O-苄基-d-葡萄糖)。加成产物中三个卤素 [C-5(三唑)> C-2(糖)> C-3(三唑)] 的分级反应性允许随后的区域选择性取代和脱保护反应,如加氢脱卤、亲核取代(通过甲醇、肼) 、苯甲胺、苯硫酚盐)、脱乙酰化和脱苄基化。因此,该论文开辟了一种新的2-脱氧糖三唑核苷类似物的合成方法。 X 射线分析支持九种产品的结构。