Total Synthesis and Absolute Configuration of Liverwort Diterpenes, (−)-13(15)E,16E-3β,4β-Epoxy-18-hydroxysphenoloba-13(15),16-diene and (−)-13(15)Z,16E-3β,4β-Epoxy-18-hydroxysphenoloba-13(15),16-diene, by Use of the Ring Closing Metathesis Reaction Applied to Seven-Membered Carbocycles with a Trisubstituted Double Bond
摘要:
Seven-membered cyclic compounds possessing trisubstituted double bonds have been effectively constructed employing the Grubbs catalyst to effect olefin metathesis. The keto ester does not undergo cyclization; however, alcohols protected by the silyl groups smoothly cyclized into seven-membered compounds. The product was successfully converted to (-)-13(15)E,16E-3P,4P-epoxy18-hydroxysphenoloba-13(15),16-diene and (-)-13(15)Z,16E-3beta,4beta-epoxy-18-hydroxysphenoloba-13(15),16-diene, liverwort diterpenes isolated from Anastrophyllum auritum to establish the absolute configuration.
Total Synthesis and Absolute Configuration of Liverwort Diterpenes, (−)-13(15)E,16E-3β,4β-Epoxy-18-hydroxysphenoloba-13(15),16-diene and (−)-13(15)Z,16E-3β,4β-Epoxy-18-hydroxysphenoloba-13(15),16-diene, by Use of the Ring Closing Metathesis Reaction Applied to Seven-Membered Carbocycles with a Trisubstituted Double Bond
摘要:
Seven-membered cyclic compounds possessing trisubstituted double bonds have been effectively constructed employing the Grubbs catalyst to effect olefin metathesis. The keto ester does not undergo cyclization; however, alcohols protected by the silyl groups smoothly cyclized into seven-membered compounds. The product was successfully converted to (-)-13(15)E,16E-3P,4P-epoxy18-hydroxysphenoloba-13(15),16-diene and (-)-13(15)Z,16E-3beta,4beta-epoxy-18-hydroxysphenoloba-13(15),16-diene, liverwort diterpenes isolated from Anastrophyllum auritum to establish the absolute configuration.
Preparation of Seven-Membered Carbocycles Using Ring-Closing Metathesis Reaction and Application to Syntheses of Tormesol and Cyathane Skeleton
作者:Katsuyuki Nakashima、Norihiro Fujisaki、Kosuke Inoue、Atsushi Minami、Chisako Nagaya、Masakazu Sono、Motoo Tori
DOI:10.1246/bcsj.79.1955
日期:2006.12
Various precursors were synthesized and were reacted with the Grubbs reagent as well as the second generation Grubbs reagent to cyclize them into seven-membered carbocycles with di- or tri-substituted double bonds. These reactions were used to synthesize (−)-tormesol, which is an enantiomer of sphenolobane-type diterpene that was isolated from Halimium viscosum, and a basic skeleton of cyathane-type diterpene.
Total Synthesis and Absolute Configuration of Liverwort Diterpenes, (−)-13(15)<i>E</i>,16<i>E</i>-3β,4β-Epoxy-18-hydroxysphenoloba-13(15),16-diene and (−)-13(15)<i>Z</i>,16<i>E</i>-3β,4β-Epoxy-18-hydroxysphenoloba-13(15),16-diene, by Use of the Ring Closing Metathesis Reaction Applied to Seven-Membered Carbocycles with a Trisubstituted Double Bond
作者:Katsuyuki Nakashima、Kosuke Inoue、Masakazu Sono、Motoo Tori
DOI:10.1021/jo020287d
日期:2002.8.1
Seven-membered cyclic compounds possessing trisubstituted double bonds have been effectively constructed employing the Grubbs catalyst to effect olefin metathesis. The keto ester does not undergo cyclization; however, alcohols protected by the silyl groups smoothly cyclized into seven-membered compounds. The product was successfully converted to (-)-13(15)E,16E-3P,4P-epoxy18-hydroxysphenoloba-13(15),16-diene and (-)-13(15)Z,16E-3beta,4beta-epoxy-18-hydroxysphenoloba-13(15),16-diene, liverwort diterpenes isolated from Anastrophyllum auritum to establish the absolute configuration.