Studies on the Synthesis of Phlegmarine-Type <i>Lycopodium</i> Alkaloids: Enantioselective Synthesis of (−)-Cermizine B, (+)-Serratezomine E, and (+)-Luciduline
作者:Alexandre Pinto、Miriam Piccichè、Rosa Griera、Elies Molins、Joan Bosch、Mercedes Amat
DOI:10.1021/acs.joc.8b00983
日期:2018.8.3
The synthesis of the Lycopodium alkaloids, (−)-cermizine B, (+)-serratezomine E, and (+)-luciduline using phenylglycinol-derived tricyclic lactams as chiral scaffolds, is reported. The requisite lactams are prepared by a cyclocondensation reaction between (R)- or (S)-phenylglycinol and the substituted δ-keto ester 11, easily accessible from (R)-pulegone. The factors governing the stereoselectivity
A practical synthetic route to enantiopure 5-substituted cis-decahydroquinolines has been developed, the key steps being a stereoselective cyclocondensation of 2-substituted 6-oxocyclohexenepropionates 2 with (R)-phenylglycinol, the stereoselective hydrogenation of the resulting unsaturated tricyclic lactams, and the stereoselective reductive cleavage of the oxazolidine ring.
Removal of the Chiral Inductor from Phenylglycinol-derived Tricyclic Lactams. Unexpected Generation of Chiral trans-Hydrochromene Lactones
作者:Rosa Griera、Alexandre Pinto、Robert Fabregat、Eric Cots、Joan Bosch、Mercedes Amat
DOI:10.2174/1570178615666171213143657
日期:2018.4.12
In the search for synthetic routes for the preparation of cis- and trans- decahydroquinolin-2-
ones, a procedure for the generation of enantiopure trans-hydrochromene lactones, by treatment of (R)-
phenylglycinol-derived oxazoloquinolone lactams with Na/liq. NH3 followed by acidification, has been
developed.
Biomimetic Construction of the Hydroquinoline Ring System. Diastereodivergent Enantioselective Synthesis of 2,5-Disubstituted <i>cis</i>-Decahydroquinolines
The straightforward enantioselective construction of the hydroquinoline ringsystemfrom 1,5-polycarbonyl derivatives, using (R)-phenyglycinol as a chiral latent form of ammonia, is reported. The process mimics the key steps believed to occur in nature in the biosynthesis of amphibian decahydroquinoline alkaloids. Diastereodivergent routes to enantiopure cis-2,5-disubstituted decahydroquinolines, including