53585-13-0Relevant academic research and scientific papers
(E)-γ-BISABOLEN-8,9-EPOXIDE AND ISOCYCLOEUDESMOL, TWO NEW SESQUITERPENOIDS FROM THE MARINE RED ALGA LAURENCIA NIPPONICA YAMADA
Suzuki, Teruaki,Kikuchi, Hajime,Kurosawa, Etsuro
, p. 1267 - 1270 (1980)
Two new sesquiterpenoids, (E)-γ-bisabolen-8,9-epoxide and isocycloeudesmol, have been isolated from L. nipponica Yamada (Rhodophyta, Rhodomelaceae) and their structures have been determined by spectroscopic and chemical evidences.
Stereochemical investigations on the biosynthesis of achiral (Z)-γ-bisabolene in Cryptosporangium arvum
Rinkel, Jan,Dickschat, Jeroen S.
supporting information, p. 789 - 794 (2019/04/17)
A newly identified bacterial (Z)-γ-bisabolene synthase was used for investigating the cyclisation mechanism of the sesquiterpene. Since the stereoinformation of both chiral putative intermediates, nerolidyl diphosphate (NPP) and the bisabolyl cation, is lost during formation of the achiral product, the intriguing question of their absolute configurations was addressed by incubating both enantiomers of NPP with the recombinant enzyme, which resolved in an exclusive cyclisation of (R)-NPP, while (S)-NPP that is non-natural to the (Z)-γ-bisabolene synthase was specifically converted into (E)-β-farnesene. A hypothetical enzyme mechanistic model that explains these observations is presented.
Isotope sensitive branching and kinetic isotope effects to analyse multiproduct terpenoid synthases from Zea mays
Gatto, Nathalie,Vattekkatte, Abith,K?llner, Tobias,Degenhardt, J?rg,Gershenzon, Jonathan,Boland, Wilhelm
supporting information, p. 3797 - 3800 (2015/03/30)
Multiproduct terpene synthases TPS4-B73 and TPS5-Delprim from Zea mays exhibit isotopically sensitive branching in the formation of mono- and sesquiterpene volatiles. The impact of the kinetic isotope effects and the stabilization of the reactive intermediates by hyperconjugation along with the shift of products from alkenes to alcohols are discussed.
Structure of epi-isozizaene synthase from streptomyces coelicolor A3(2), a platform for new terpenoid cyclization templates
Aaron, Julie A.,Lin, Xin,Cane, David E.,Christianson, David W.
experimental part, p. 1787 - 1797 (2011/02/22)
The X-ray crystal structure of recombinant epi-isozizaene synthase (EIZS), a sesquiterpene cyclase from Streptomyces coelicolor A3(2), has been determined at 1.60 A resolution. Specifically, the structure of wild-type EIZS is that of its closed conformation in complex with three Mg2+ ions, inorganic pyrophosphate (PPi), and the benzyltriethylammonium cation (BTAC). Additionally, the structure of D99N EIZS has been determined in an open, ligand-free conformation at 1.90 A resolution. Comparison of these two structures provides the first view of conformational changes required for substrate binding and catalysis in a bacterial terpenoid cyclase. Moreover, the binding interactions of BTAC may mimic those of a carbocation intermediate in catalysis. Accordingly, the aromatic rings of F95, F96, and F198 appear to be well-oriented to stabilize carbocation intermediates in the cyclization cascade through cation π interactions. Mutagenesis of aromatic residues in the enzyme active site results in the production of alternative sesquiterpene product arrays due to altered modes of stabilization of carbocation intermediates as well as altered templates for the cyclization of farnesyl diphosphate. Accordingly, the 1.64 A resolution crystal structure of F198A EIZS in a complex with three Mg2+ ions, PPi, and BTAC reveals an alternative binding orientation of BTAC; alternative binding orientations of a carbocation intermediate could lead to the formation of alternative products. Finally, the crystal structure of wild-type EIZS in a complex with four Hg 2+ ions has been determined at 1.90 A resolution, showing that metal binding triggers a significant conformational change of helix G to cap the active site.
Stereoselective synthesis of exocyclic alkenes by Cu-catalyzed allylmagnesiation, Pd-catalyzed alkylation, and Ru-catalyzed ring-closing metathesis: Highly stereoselective synthesis of (Z)- and (E)-γ-bisabolenes
Anastasia, Luigi,Dumond, Yves R.,Negishi, Ei-Ichi
, p. 3039 - 3043 (2007/10/03)
Highly efficient stereoselective syntheses of both (Z)- and (E)-γ-bisabolenes (1) were achieved by ring closing metathesis of stereodefined tetrasubstituted alkenes. Both (Z)- and (E)-tetrasubstituted alkene precursors were obtained by Cu-catalyzed stereoselective addition of allylmagnesium bromide to propargyl alcohols, followed by Pd-catalyzed cross coupling of alkylzinc derivatives. This represents the first application of ring-closing metathesis to the stereoselective synthesis of exocyclic alkenes.
Sesquiterpenes produced by truncated taxadiene synthase
Huang,Williams,Roessner,Scott
, p. 9701 - 9704 (2007/10/03)
Soluble, highly active N-terminal truncated taxadiene synthase catalyzes the formation of an isomeric mixture of taxadienes from geranylgeranyl diphosphate. Farnesyl diphosphate was also found to be a good substrate, producing four sesquiterpenes which were characterized. The dual activities of taxadiene synthase and product inhibition caused by sesquiterpene metabolites make it imperative that active GGDP synthase be present in order for multi-enzyme systems to follow the taxol pathway in vitro. (C) 2000 Published by Elsevier Science Ltd.
A SIMPLE STEREOSELECTIVE SYNTHESIS OF Z-γ-BISABOLENE.
Corey, E. J.,Seibel, William L.
, p. 909 - 910 (2007/10/02)
A simple one-flask synthesis of Z-γ-bisabolene (1) from the acyclic acetylene 2 is described.
CHIRAL LEAVING GROUP: ASYMMETRIC SYNTHESIS OF LIMONENE AND BISABOLENE
Sakane, Soichi,Fujiwara, Junya,Maruoka, Keiji,Yamamoto, Hisashi
, p. 2193 - 2202 (2007/10/02)
The biogenetic-type asymmetric synthesis of limonene and bisabolenes is described.As model studies for the present asymmetric synthesis, the cyclization of catechol, biphenol and binaphthol mononeryl ethers 1, 4, and 5, with organoaluminium reagents are executed to furnish limonene as a major product.Since the reaction of 1, 4, and 5 has proved to proceed much faster than that of neryl phenyl ether under the similar conditions, the rate acceleration is attributed to the novel metal-anchimeric assistance of the aluminium reagents bound with the neighboring hydroxyl group for effecting the generation of the allyl cathion.This anchimeric effect is utilized for the enantioselective cyclization of (R)-(+)-1,1'-bi-2-naphthol mononeryl ether (8) upon treatment with modified aluminium reagent 9 to produce limonene with high optical purity (77percent ee).In a similar fashion, (R)-(+)-binaphtol (Z,Z)-monofarnesyl ether 16a undergoes the enantioselective cyclization to give β-bisabolene in 76percent ee.
FIRST STEREOSPECIFIC SYNTHESIS OF E-γ-BISABOLENE. A METHOD FOR THE CONCURRENT GENERATION OF A RING AND A TETRASUBSTITUTED EXOCYCLIC DOUBLE BOND.
Corey, E. J.,Seibel, William L.
, p. 905 - 908 (2007/10/02)
A short stereospecific synthesis of E-γ-bisabolene (1) from an acyclic acetylenic precursor (either 2 or 6) is described.
AN ELECTROCHEMICAL METHOD SPECIFICALLY DIRECTED TO THE PREPARATION OF DL-BISABOLOL FROM DL-NEROLIDOL
Uneyama, Kenji,Masatsugu, Yosinori,Ueda, Takesi,Torii, Sigeru
, p. 529 - 530 (2007/10/02)
A product-selective electrosynthesis of dl-bisabolol from dl-nerolidol was accomplished by a constant current electrolysis in commercial acetone containing a small amount of LiClO4
