Enantiospecific Synthesis of (+)- and (−)-Ferruginine from l-Glutamic Acid. Synthesis of Tropanes via Intramolecular Iminium Ion Cyclization
摘要:
Iminium ions, generated by decarbonylation of N-benzyl-5-[1-(methoxycarbonyl)-4-oxopentyl]-prolines, prolines, undergo intramolecular cyclization to afford 2,4-disubstituted tropanes in good yields. This transformation is also shown to be a stereospecific reaction. The value of these substituted tropanes has been demonstrated by functional group manipulation, leading to the enantiospecific synthesis of (+)-ferruginine, an alkaloid isolated from Darlinga ferruginea, and its unnatural enantiomer, (-)-ferruginine.
Jasmonoids with cis-2-pentenyl side chain such as cis-jasmone, methyl jasmonate, and jasmolone were easily synthesized from cis-4-heptenoic acid obtained by the ring opening reaction of β-propiolactone with di-cis-butenylcuprate.
A new ready route to 1,4-ketoaldehydes and 1,4-diketones with application to the synthesis of z-jasmone and dihydrojasmone
作者:V Fiandanese、G Marchese、F Naso
DOI:10.1016/0040-4039(88)85300-0
日期:1988.1
A new three-step synthesis in good overall yield of 1,4-ketoaldehydes and 1,4-diketones is described. The method involves two sequential coupling reactions of Grignard reagents with S-phenyl carbonochloridothioate in the presence of nickel(II) or iron(III) complexes as catalysts. Application of this reaction to the synthesis of Z-jasmone and dihydrojasmone is also described.
General Access to Concave-Substituted <i>cis</i>-Dioxabicyclo[3.3.0]octanones: Enantioselective Total Syntheses of Macfarlandin C and Dendrillolide A
作者:Tyler K. Allred、André P. Dieskau、Peng Zhao、Gregory L. Lackner、Larry E. Overman
DOI:10.1021/acs.joc.0c02273
日期:2020.12.4
involves late-stage fragment coupling of a tertiary-carbon radical and an electron-deficient double bond to form vicinal quaternary and tertiary stereocenters with high fidelity. A stereoselective Mukaiyama hydration is the key step in the subsequent elaboration of the cis-2,8-dioxabicyclo[3.3.0]octan-3-one moiety. This strategy was utilized in enantioselective totalsyntheses of (−)-macfarlandin C and
Total Synthesis of Panaginsene with Structural Revision
作者:Sujeong Geum、Hee-Yoon Lee
DOI:10.1021/ol500849m
日期:2014.5.2
A facile total synthesis of the reported structure for panaginsene through a trimethylenemethane (TMM) diylmediated tandem cycloadditionreaction revealed that the spectroscopic data of the synthesized structure did not match with the data of the natural product. The total synthesis of the stereoisomer of the reported structure confirmed that the correct structure of panaginsene was the 11-epi stereoisomer
Asymmetric Total Synthesis of Cladosporin and Isocladosporin
作者:Huaiji Zheng、Changgui Zhao、Bowen Fang、Peng Jing、Juan Yang、Xingang Xie、Xuegong She
DOI:10.1021/jo300805n
日期:2012.7.6
The first asymmetric total syntheses of cladosporin and isocladosporin were accomplished in 8 steps with 8% overall yield and 10 steps with 26% overall yield, respectively. The relative configuration of isocladosporin was determined via this totalsynthesis.