Treatment of the lithium derivatives of 17α-ethynyl steroids with bromotrifluoromethane or heptafluoro-1-iodopropane in liquid ammonia afforded, respectively, the corresponding 17α-bromoethnynyl or 17α-iodoethynyl steroids in satisfactory yields.
Novel 17α-bromoethynyl, 17α-chloroethynyl, 17-αiodoethynyl, 17-αtrifluoropropynyl, 17α-vinyl and 17α-triflourovinyl-17β-hydroxy (and/or 17β-alkoxy)-steroids have been prepared for biological examination.
A Copper-Catalyzed N-Alkynylation Route to 2-Substituted N-Alkynyl Pyrroles and Their Cyclization into Pyrrolo[2,1-c]oxazin-1-ones: A Formal Total Synthesis of Peramine
作者:Brandon Reinus、Sean Kerwin
DOI:10.1055/s-0036-1588736
日期:2017.6
cross-coupling of alkynyl bromides with pyrroles, reveals that the use of the phenanthroline ligand 4,7-dimethoxy-1,10-phenanthroline affords a range of ynpyrroles in good to moderate yields. Furthermore, the utility of these ynpyrroles is demonstrated in the preparation of a series of pyrrolo[2,1-c][1,4]oxazin-1-ones and a formal total synthesis of the pyrrole natural product peramine. Screening of a variety of
摘要 炔丙基溴与吡咯的铜催化交叉偶联的各种配体和反应条件的筛选表明,使用菲咯啉配体4,7-二甲氧基-1,10-菲咯啉可提供一系列良好的炔吡咯中等产量。此外,这些吡咯的用途在一系列吡咯并[2,1 - c ] [1,4]恶嗪-1-酮的制备和吡咯天然产物过胺的正式全合成中得到了证明。 炔丙基溴与吡咯的铜催化交叉偶联的各种配体和反应条件的筛选表明,使用菲咯啉配体4,7-二甲氧基-1,10-菲咯啉可提供一系列良好的炔吡咯中等产量。此外,这些吡咯的用途在一系列吡咯并[2,1 - c ] [1,4]恶嗪-1-酮的制备和吡咯天然产物过胺的正式全合成中得到了证明。
Manganese-Catalyzed C−H Alkynylation: Expedient Peptide Synthesis and Modification
catalysis manifold enabled C−H couplings with haloalkynes featuring, among others, fluorescent labels, steroids, and amino acids, thereby setting the stage for peptide ligation as well as the efficient molecular assembly of acyclic and cyclic peptides. A plausible catalytic cycle was proposed.