60410-16-4Relevant articles and documents
A convergent, enantioselective total synthesis of streptogramin antibiotic (-)-madumycin II
Ghosh, Arun K.,Liu, Wenming
, p. 7908 - 7909 (1997)
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Studies towards the total synthesis of an epoxy isoprostane phospholipid, a potent activator of endothelial cells.
Jung, Michael E,Kers, Annika,Subbanagounder, Ganesamoorthy,Berliner, Judith A
, p. 196 - 197 (2003)
We report studies toward the total synthesis of an epoxy isoprostane, namely the preparation of compound 9 which is an analogue of the elimination product 7 of the naturally occurring epoxy isoprostane 4 by a straightforward route using a three-component coupling, and have shown by several spectroscopic criteria that it closely resembles the natural material.
PALLADIUM-CATALYZED INTRAMOLECULAR OLEFIN ALLYLATIONS: STEREOCONTROLLED SYNTHESES OF BICYCLIC SYSTEMS AND EVIDENCE FOR AN ALLYLPALLADIUM/OLEFIN-CIS-INSERTION
Oppolzer, Wolfgang,Gaudin, Jean-Marc,Birkinshaw, Timothy N.
, p. 4705 - 4708 (1988)
Pd(0)-catalyzed cyclizations of (1-acetoxy-3-alkenyl)-2-cycloalkenes 3, 6 and 12 provide bicyclic systems in high diastereo- (5, 8) and enantio-meric (14) purity consistent with a predominant allylpalladium/alkene cis- insertion.
Acylative desymmetrization of cyclic meso-1,3-diols by chiral DMAP derivatives
Mandai, Hiroki,Hironaka, Tsubasa,Mitsudo, Koichi,Suga, Seiji
supporting information, p. 471 - 474 (2021/03/15)
An efficient enantioselective acylative desymmetrization of cyclic meso-1,3-diols was developed by using a chiral DMAP derivative 1e having a 1,1¤-binaphthyl unit. The reactions required only 0.5mol% of the catalyst and showed good to excellent enantioselectivity. With this transformation, 5a, a key building block for the synthesis of natural products, was easily obtained in almost enantiomerically pure form after a single recrystallization. Control experiments revealed that tert-alcohol units on the catalyst were responsible for both the catalytic activity and enantioselectivity.
Enantioselective Total Synthesis of (+)-Nordasycarpidone, (+)-Dasycarpidone, and (+)-Uleine
Delayre, Bastien,Fung, Cédric,Wang, Qian,Zhu, Jieping
, (2021/07/12)
The structure of uleine type alkaloids is characterized by the presence of a bridged tetracyclic hexahydro-1H-1,5-methanoazocino[4,3-b]indole ring system 1. Various strategies have been developed to access this polycyclic structural motif. We report herein a one-step conversion of appropriately functionalized 1,3,4-trisubstituted cyclopent-1-ene to 1 by way of an integrated oxidation/reduction/cyclization (iORC) process. This domino sequence, initiated by oxidative cleavage of cyclopentene ring, generated subsequently a cyclohexenone, an indole and a 1,3-bridged piperidine ring through formation of one C?C and two C?N bonds. Compound 1 is subsequently converted to nordasycarpidone, dasycarpidone and uleine. The chirality of the molecule was introduced by enzymatic desymmetrization of commercially available meso cis-3,5-diacetoxy-1-cyclopentene.
TiCl3-Mediated Synthesis of 2,3,3-Trisubstituted Indolenines: Total Synthesis of (+)-1,2-Dehydroaspidospermidine, (+)-Condyfoline, and (?)-Tubifoline
Delayre, Bastien,Piemontesi, Cyril,Wang, Qian,Zhu, Jieping
supporting information, p. 13990 - 13997 (2020/06/10)
2,3,3-Trisubstituted indolenine constitutes an integral part of many biologically important monoterpene indole alkaloids. We report herein an unprecedented access to this skeleton by a TiCl3-mediated reductive cyclization of tetrasubstituted alkenes bearing a 2-nitrophenyl substituent. The proof of concept is demonstrated firstly by accomplishing a concise total synthesis of (+)-1,2-dehydroaspidospermidine featuring a late-stage application of this key transformation. A sequence of reduction of nitroarene to nitrosoarene followed by 6π-electron-5-atom electrocyclization and a 1,2-alkyl shift of the resulting nitrone intermediate was proposed to account for the reaction outcome. A subsequent total synthesis of (+)-condyfoline not only illustrates the generality of the reaction, but also provides a mechanistic insight into the nature of the 1,2-alkyl shift. The exclusive formation of (+)-condyfoline indicates that the 1,2-alkyl migration follows a concerted Wagner–Meerwein pathway, rather than a stepwise retro-Mannich/Mannich reaction sequence. Conditions for almost quantitative conversion of (+)-condyfoline to (?)-tubifoline by way of a retro-Mannich/1,3-prototropy/transannular cyclization cascade are also documented.
