Stereoselective Total Syntheses of Polyacetylene Plant Metabolites via Ester-Tethered Ring Closing Metathesis
作者:Bernd Schmidt、Stephan Audörsch
DOI:10.1021/acs.joc.6b02987
日期:2017.2.3
Totalsyntheses of five naturally occurring polyacetylenes from three different plants are described. These natural products have in common an E,Z-configured conjugated diene linked to a di- or triyne chain. As the key method to stereoselectively establish the E,Z-diene part, an ester-tethered ring-closing metathesis/base-induced eliminative ring opening sequence was used. The results presented herein
Multiheterocyclic Motifs via Three-Component Reactions of Benzynes, Cyclic Amines, and Protic Nucleophiles
作者:Sean P. Ross、Thomas R. Hoye
DOI:10.1021/acs.orglett.7b03458
日期:2018.1.5
general, three-component reaction strategy for the construction of compounds containing multiple heterocycles is described. Thermal benzyne formation (by the hexadehydro-Diels–Alder (HDDA) reaction) in the presence of tertiary cyclic amines and a protic nucleophile (HNu) gives, via ring-opening of intermediate ammonium ion/Nu– ion pairs, heterocyclic products. Many reactions are efficient even when
Natural acetylenes. Part XX. Tetra-acetylenic and other metabolites from Fistulina hepatica(Huds) Fr.
作者:Ewart R. H. Jones、G. Lowe、P. V. R. Shannon
DOI:10.1039/j39660000139
日期:——
structure determination of five polyacetylenes from Fistulina hepatica are described. They include two C13-tetra-acetylenic compounds which, in addition to adding a new chromophore to those of the fungal metabolites, also represent the first hydrocarbon (I) and the first tetra-ol (V) to be encountered. The structure and stereochemistry of the tetra-ol (V) followed from two experiments; firstly, periodate oxidation