Acid-catalyzed isomerization of caryophyllene in the presence of SiO2 and Al2O3 impregnated with sulfuric acid
作者:E. P. Romanenko、A. V. Tkachev
DOI:10.1007/s11172-018-2179-3
日期:2018.6
The conversion of caryophyllene upon contact with Al2O3 and SiO2 impregnated with sulfuric acid was carried out, and the components of the resulting mixtures were identified. Having in hands such “standard” mixtures greatly facilitates identification of components of sesquiterpene fractions of essential oils and other mixtures of natural origin. The catalytic activity of silica gel impregnated with
Rational reprogramming of the sesquiterpene synthase BcBOT2 yields new terpenes with presilphiperfolane skeleton
作者:Vanessa Nikolaiczyk、Jenny Irwan、Trang Nguyen、Jörg Fohrer、Philipp Elbers、Paul Schrank、Mehdi D. Davari、Andreas Kirschning
DOI:10.1039/d2cy01617f
日期:——
Computer-aided rational design allowed to create variants of the sesquiterpene cyclase BcBOT2 that yielded novel tricyclic presilphiperfolane-type sesquiterpenes.
Solvolysis of Caryophyllen-8β-yl Derivatives: Biomimetic Rearrangement−Cyclization to 12-Nor-8α-presilphiperfolan-9β-ol
作者:Sriram Shankar、Robert M. Coates
DOI:10.1021/jo971984m
日期:1998.12.1
The solvolyses of caryophyllen-8 beta-yl p-nitrobenzoate (14-OpNB) and 15-norcaryophyllen-8 beta-yl tosylate (15-OTs) were investigated as potential model reactions for the biogenesis of the tricyclic presilphiperfolanol sesquiterpenes. Buffered solvolysis of 14-OpNB in 60% aqueous acetone at 125 degrees C afforded caryophyllene (3) as major product, accompanied by small amounts of caryophyllen-8 beta-ol (14-OH) and 5,8-cyclocaryophyllen-4 alpha-ol (16). In contrast, 15-OTs underwent a stereospecific rearrangement-cyclization to 12-nor-8 alpha-presilphiperfolan-9 beta-ol (17) upon solvolysis in 60% aqueous acetone at 75 degrees C. The structure and stereochemistry of this trans,cis,trans-tricyclo[6.2.1.0(5,11)]undecane derivative were established by NMR correlation spectroscopy and X-ray crystallography. Two different mechanisms (paths A and B) for the conversion of 15-OTs to 17 by initial 1,2-migration of either the external or internal cyclobutane ring bonds (C10 and C1) followed by pi-sigma cyclization onto the trans double bond are discussed.
Four-Step Access to the Sesquiterpene Natural Product Presilphiperfolan-1β-ol and Unnatural Derivatives via Supramolecular Catalysis
作者:Leonidas-Dimitrios Syntrivanis、Ivana Némethová、Dario Schmid、Shani Levi、Alessandro Prescimone、Fabian Bissegger、Dan T. Major、Konrad Tiefenbacher
DOI:10.1021/jacs.0c01464
日期:2020.3.25
su-pramolecular resorcinarene capsule as catalyst for the key step. This syntheticapproach also allows access to unnatural derivatives of the natural product, which would not be acces-sible through the biosynthetic machinery. Additionally, this study provides useful insight into the biosynthesis of the presilphiperfolanol natural products, including the first ex-perimental evidence consistent with the