作者:Jean-Paul R. Hermet、Matthew J. McGrath、Peter O'Brien、David W. Porter、John Gilday
DOI:10.1039/b406632d
日期:——
A six-step asymmetricsynthesis of natural (-)-sparteine from ethyl 7-iodohept-2-enoate is reported, involving a connective Michael addition of an amino ester-derived enolate to an alpha,beta-unsaturated amino ester.
A two-directionalsynthesis of (+)-β-isosparteine is described in five steps from glutaric acid, where the entire carbon and nitrogen backbone of the alkaloid, possessing the requisite relative and absolute stereochemistry at its four stereogenic centers, is assembled using a double imino-aldol reaction.
Gram-Scale Synthesis of the (−)-Sparteine Surrogate and (−)-Sparteine
作者:James D. Firth、Steven J. Canipa、Leigh Ferris、Peter O'Brien
DOI:10.1002/anie.201710261
日期:2018.1.2
An 8‐step, gram‐scale synthesis of the (−)‐sparteine surrogate (22 % yield, with just 3 chromatographic purifications) and a 10‐step, gram‐scale synthesis of (−)‐sparteine (31 % yield) are reported. Both syntheses proceed with complete diastereocontrol and allow access to either antipode. Since the syntheses do not rely on natural product extraction, our work addresses long‐term supply issues relating