The totalsynthesis of (±)-aspergilline A (1) is described. Key features of the synthesis include pyrrolinone formation via reaction of an intermediate propargyl amine with a methyl malonyl chloride derived ammonium enolate and a formal [3+2] cycloaddition between an imidate and cyclopropenone.
描述了 (±)-aspergilline A (1) 的全合成。该合成的关键特征包括通过中间体炔丙胺与甲基丙二酰氯衍生的烯醇铵反应形成吡咯啉酮,以及亚胺酸酯和环丙烯酮之间的正式 [3+2] 环加成。
The synthesis of hydroxy-pyrrolizidines and indolizidines from cyclopropenones: towards hyacinthacines, australines and jenamidines
pyrrolizidines and indolizidines, respectively, each with a hydroxy group on the carbon atom at the bridgehead. The cyclopropenone functions as an all-carbon 1,3-dipole equivalent towards the cyclic imine in this reaction, and the cyclic imines used include polyhydroxylated systems, thus allowing access to australine, alexine and hyacinthacine type compounds. The pyrrolizidine products contain the core of the
General synthesis of cyclopropenones and their acetals
作者:Masahiko Isaka、Satoshi Ejiri、Eiichi Nakamura
DOI:10.1016/s0040-4020(01)88873-6
日期:——
Metalated cyclopropenone acetals 5 react with a variety of electrophiles, including alkyl halides, carbonylcompounds, vinyl iodides, vinyl triflates, and aryl iodides, to give substituted cyclopropenone acetals in high yield. Hydrolysis of the acetal under acidic conditions gives the corresponding cyclopropenone. The reaction sequence has realized an efficient synthesis of an antibiotic penitricin
Cyclopropenones in the synthesis of indolizidine, pyrrolo[2,1-a]isoquinoline and indolizino[8,7-b]indole alkaloids
作者:Faisal Jamshaid、Vishnu V.R. Kondakal、C. Declan Newman、Rhianne Dobson、Heidi João、Craig R. Rice、Joseph M. Mwansa、Bimod Thapa、Karl Hemming
DOI:10.1016/j.tet.2020.131570
日期:2020.11
the synthesis of pyrrolo[1,2-a]isoquinolines from the reaction of aldimine dihydroisoquinolines with cyclopropenones, whereas ketimine based dihydroisoquinolines gave pyrrolo[1,2-a]isoquinolines without bridgehead oxidation. These results may have some significance for the origins of the bridgehead hydroxy natural products jenamidine B1/B2, clazamycin A/B and legonmycin A/B. The precursor cyclic aldimine
吲哚并咪唑天然产物粟精胺的尝试合成导致成功地将环丙烯酮添加到糖衍生的多羟基化环亚胺中,得到吲哚嗪酮产品,但是在粟精胺8a-桥头位置上安装了额外的羟基。这在我们以前对奥曲林和风信子吡咯并核苷天然产物的处理中也观察到。由醛亚胺二氢异喹啉与环丙烯酮反应合成吡咯并[1,2- a ]异喹啉时发生了相同的氧化现象,而酮亚胺基二氢异喹啉则产生了吡咯并[1,2- a]异喹啉,无桥头氧化。这些结果可能对桥头羟基天然产物啶B 1 / B 2,克拉扎霉素A / B和莱顿霉素A / B的起源具有重要意义。用于合成吲哚并[8,7- b ]吲哚的前体环状醛亚胺产生二聚吲哚并[8,7- b ]吲哚,而相应的环状酮亚胺表现出预期并得到吲哚并[8,7- b ]吲哚。与环丙烯酮反应后的核心。
A new and simple method for the synthesis of highly functionalised pyrrolizidines, indolizidines and pyrroloazepines
作者:Paul A. O’Gorman、Ting Chen、Hannah E. Cross、Saleena Naeem、Arnaud Pitard、M. Ilyas Qamar、Karl Hemming
DOI:10.1016/j.tetlet.2008.08.061
日期:2008.10
The reaction of 5-, 6- and 7-membered cyclic thioimidates with cyclopropenones gives access to highly functionalised pyrrolizidines, indolizidines and pyrroloazepines via a formal [3+2] cycloaddition process.