The role of germacrene D as a precursor in sesquiterpene biosynthesis: investigations of acid catalyzed, photochemically and thermally induced rearrangements
作者:Nils Bülow、Wilfried A König
DOI:10.1016/s0031-9422(00)00266-1
日期:2000.9
Germacrene D is considered as a precursor of many sesquiterpene hydrocarbons. We have investigated the acid catalyzed as well as the photochemically and thermallyinducedrearrangement processes of germacrene D isolated from several Solidago species, which contain both enantiomers of germacrene D. Enantiomeric mixtures of sesquiterpenes of the cadinane, eudesmane (selinane), oppositane, axane, isodaucane
Germacrene D 被认为是许多倍半萜烃的前体。我们研究了从几种一枝黄花物种中分离出的锗烯 D 的酸催化以及光化学和热诱导的重排过程,其中含有锗烯 D 的两种对映异构体。 cadinane、eudesmane (selinane)、oppositane、axane、异十二烷和波旁烷组以及异热菌烯 D 被确定为主要产品,并可作为参考化合物用于植物成分的结构研究和立体化学分配。重排产物之一的 Delta-amorphene 首次被确定为天然产物。γ-阿吗啡的绝对构型通过与锗烯 D 的绝对构型的相关性进行了修正。
Khusinol, a new crystalline secondary sesquiterpenealcohol, isolated from North Indian vetiver oil (Vetiveria zizaniodes, Linn) is shown to have the absolute configuration represented by the structure XX on the basis of degradative experiments and its conversion to (−)-γ-cadinene under mild conditions. It belongs to the unusual antipodal group of cadinenes. γ1-Cadinene(XXI) isolated from Malabar lemongrass
Khusol, a crystalline primary sesquiterpene alcohol, C15H24O, isolated from North Indian vetiver oil has been assigned the structure and absoluteconfiguration represented by I. It belongs to the antipodal group of cadinenic alcohols.
从印度北部香根草油中分离得到的Khusol(一种结晶的倍半萜烯醇,C 15 H 24 O)已被赋予I所示的结构和绝对构型。
Lessons from 1,3-Hydride Shifts in Sesquiterpene Cyclizations
作者:Jan Rinkel、Patrick Rabe、Paolina Garbeva、Jeroen S. Dickschat
DOI:10.1002/anie.201608042
日期:2016.10.17
initial 1,10‐cyclisation‐1,3‐hydride shift cascades. Enzymes with products of known absolute configuration showed a coherent stereochemical course, except for (−)‐α‐amorphene synthase, for which the obtained results are better explained by an initial 1,6‐cyclisation. The link between the absolute configuration of the product and the stereochemical course of the 1,3‐hydride shifts enabled assignment of
Mechanistic characterization of three sesquiterpene synthases from the termite-associated fungus <i>Termitomyces</i>
作者:Immo Burkhardt、Nina B. Kreuzenbeck、Christine Beemelmanns、Jeroen S. Dickschat
DOI:10.1039/c8ob02744g
日期:——
D-4-ol synthase as the first reported enzyme that produces the (+)-enantiomer. The enzymatic mechanisms were thoroughly investigated by incubation with isotopically labeled precursors to follow the stereochemicalcourses of single reaction steps in catalysis. The role of putative active site residues was tested by site directed mutagenesis of a highly conserved tryptophan in all three enzymes and additional