28161-78-6Relevant academic research and scientific papers
Enantioselective Michael/aza-Michael/Cyclization organocascade to tetracyclic spiroindolines: Concise total synthesis of kopsinine and aspidofractine
Wu, Xiaoyu,Huang, Jianbiao,Guo, Beibei,Zhao, Long,Liu, Yong,Chen, Jie,Cao, Weiguo
, p. 3377 - 3382 (2014)
Kopsinine and related alkaloids are attractive synthetic targets because of their structural complexity and biological activities. An organocatalytic Michael addition/aza-Michael addition/cyclization cascade sequence has been developed for the enantioselective preparation of tetracyclic spiroindolines from 2,3-disubstituted indoles and propargyl aldehyde in moderate to good yields and good to excellent enantioselectivities. The synthetic value of these advanced structures has been demonstrated by the synthesis of kopsinine and related alkaloids. Key steps for the concise synthesis of these alkaloids included an efficient enantioselective construction of tetracyclic spiroindolines bearing a dienamino ester moiety and the organocatalyzed nucleophilic addition of a dienamino ester to acrolein.
Collective synthesis of natural products by means of organocascade catalysis
Jones, Spencer B.,Simmons, Bryon,Mastracchio, Anthony,MacMillan, David W. C.
scheme or table, p. 183 - 188 (2012/05/20)
Organic chemists are now able to synthesize small quantities of almost any known natural product, given sufficient time, resources and effort. However, translation of the academic successes in total synthesis to the large-scale construction of complex natural products and the development of large collections of biologically relevant molecules present significant challenges to synthetic chemists. Here we show that the application of two nature-inspired techniques, namely organocascade catalysis and collective natural product synthesis, can facilitate the preparation of useful quantities of a range of structurally diverse natural products from a common molecular scaffold. The power of this concept has been demonstrated through the expedient, asymmetric total syntheses of six well-known alkaloid natural products: strychnine, aspidospermidine, vincadifformine, akuammicine, kopsanone and kopsinine.
Total Synthesis of (-)-Kopsinilam, (-)-Kopsinine, and the Bis-indole Alkaloids (-)-Norpleiomutine and (-)-Pleiomutine
Magnus, Philip,Brown, Peter
, p. 184 - 186 (2007/10/02)
The racemic tetracyclic amine (5) was resolved and converted into (-)-kopsinine (16); subsequent coupling to (-)-eburnamine (2) gave (-)-norpleiomutine (4).
