A variety of approaches towards the synthesis of lincosamine, a derived portion of the antibiotic lincomycin , are reported. Initial approaches involved the intramolecular delivery of a nitrogen atom ( trichloroacetimidate , trichloroacetylcarbamate , carbamate, 2-amino-2- phenylacetate ) attached to O4 onto C6 of a 6,7-anhydrooctoside. Later approaches, albeit more direct but again largely unsuccessful, involved the Sharpless titanium(IV)-mediated nucleophilic opening of a suitable 6,7-anhydrooctose, and the Sharpless oxyamination and the aziridination of suitable octenoses . As an aid to the structure elucidation of several compounds encountered in this work, single-crystal X-ray structure determinations are reported for methyl 6,7-anhydro-2,3-di-O-benzyl-8-deoxy-α-D-threo-D-galacto-octopyranoside , methyl 6,7-anhydro-2,3-di-O-benzyl-8-deoxy-α-D-threo-D-gluco-octopyranoside and 7-azido-7-deoxy-1,2:3,4-di-O-isopropylidene-β-L-erythro-Dgalacto-octose.
据报道,合成抗生素
林可霉素衍生部分林可胺的方法多种多样。最初的方法是在分子内将一个氮原子(三
氯乙酰亚
氨酸、三
氯乙酰
氨基甲酸酯、
氨基甲酸酯、
2-氨基-2-苯基乙酸酯)连接到 6,7-脱
水辛糖苷的 C6 的 O4 上。后来的方法(虽然更直接,但基本上也不成功)包括由 Sharpless
钛(IV)介导的合适的 6,7-anhydrooctose 的亲核开路,以及合适的
辛烯糖的 Sharpless 氧化和
叠氮化。为了帮助阐明这项工作中遇到的几种化合物的结构,报告了甲基 6,7-anhydro-2,3-di-O-benzyl-8-deoxy-α-D-threo-D-galacto-ctopyranoside 、甲基 6,7-anhydro-2,3-di-O-benzyl-8-deoxy-α-D-threo-D-gluco-ctopyranoside 和 7-azido-7-deoxy-1,2:3,4-二-O-异亚丙基-β-L-赤式-
D-半乳糖苷。