Terpenoids comprise the largest family of natural products and include various structurally different genus which play important roles in living organisms. Biosynthetically, diterpenoids are derived from （E,E,E）-ger...Terpenoids comprise the largest family of natural products and include various structurally different genus which play important roles in living organisms. Biosynthetically, diterpenoids are derived from （E,E,E）-geranylgeranyl diphosphate （GGPP）. From GGPP, diterpene cyclase catalyzes a sequence of carbocation- mediated cyclizations, rearrangements, and further oxidations, leading to a class of structurally unique ent-kaurenes, such as cafestol, gibberellin A3 and oridonin. According to the biosynthesis pathway of ent-kaurene, we designed a chiral acetal-enabled and SnCln-promoted biomimetic polyene cationic cyclization. With a following Birch reduc- tiort/alkylation cascade, a core skeleton of representative ent-kaurenes diterpenoids was completed.展开更多
A new 1β-hydroxy-ent-kauren diterpenoid, enanderianin C1, has been isolated from the leaves of Isodon enanderianus, and its structure has been elucidated by spectroscopic evidences.
Two new diterpenoids taibairubescensin A (1) and B (2) have been isolated from Isodon rubescens. The structures of compound 1 and 2 were elucidated as 2 beta,3 beta-diacetoxy-11 beta,13 alpha-dihydroxy-ent-kaur- 16-en...Two new diterpenoids taibairubescensin A (1) and B (2) have been isolated from Isodon rubescens. The structures of compound 1 and 2 were elucidated as 2 beta,3 beta-diacetoxy-11 beta,13 alpha-dihydroxy-ent-kaur- 16-en-15-one (1) and 3 beta,11 beta-diacetoxy-2 beta,6 alpha-dihydroxy-ent-kaur-16-en-15-one (2) on the basis of spectroscopic analysis.展开更多
文摘Terpenoids comprise the largest family of natural products and include various structurally different genus which play important roles in living organisms. Biosynthetically, diterpenoids are derived from （E,E,E）-geranylgeranyl diphosphate （GGPP）. From GGPP, diterpene cyclase catalyzes a sequence of carbocation- mediated cyclizations, rearrangements, and further oxidations, leading to a class of structurally unique ent-kaurenes, such as cafestol, gibberellin A3 and oridonin. According to the biosynthesis pathway of ent-kaurene, we designed a chiral acetal-enabled and SnCln-promoted biomimetic polyene cationic cyclization. With a following Birch reduc- tiort/alkylation cascade, a core skeleton of representative ent-kaurenes diterpenoids was completed.
文摘A new 1β-hydroxy-ent-kauren diterpenoid, enanderianin C1, has been isolated from the leaves of Isodon enanderianus, and its structure has been elucidated by spectroscopic evidences.
文摘Two new diterpenoids taibairubescensin A (1) and B (2) have been isolated from Isodon rubescens. The structures of compound 1 and 2 were elucidated as 2 beta,3 beta-diacetoxy-11 beta,13 alpha-dihydroxy-ent-kaur- 16-en-15-one (1) and 3 beta,11 beta-diacetoxy-2 beta,6 alpha-dihydroxy-ent-kaur-16-en-15-one (2) on the basis of spectroscopic analysis.
