142288-39-9Relevant articles and documents
Identification, synthesis and mass spectrometry of a macrolide from the African reed frog Hyperolius cinnamomeoventris
Menke, Markus,Peram, Pardha Saradhi,Starnberger, Iris,H?dl, Walter,Jongsma, Gregory F. M.,Blackburn, David C.,R?del, Mark-Oliver,Vences, Miguel,Schulz, Stefan
, p. 2731 - 2738 (2016)
The contents of the gular glands of the male African reed frog Hyperolius cinnamomeoventris consist of a mixture of aliphatic macrolides and sesquiterpenes. While the known macrolide gephyromantolide A was readily identified, the structure of another major component was suggested to be a tetradecen-13-olide. The synthesis of the two candidate compounds (Z)-5- and (Z)-9-tetradecen-13-olide revealed the former to be the naturally occurring compound. The synthesis used ring-closing metathesis as key step. While the Hoveyda-Grubbs catalyst furnished a broad range of isomeric products, the (Z)-selective Grubbs catalyst lead to pure (Z)-products. Analysis by chiral GC revealed the natural frog compound to be (5Z,13S)-5-tetradecen-13-olide (1). This compound is also present in the secretion of other hyperoliid frogs as well as in femoral glands of male mantellid frogs such as Spinomantis aglavei. The mass spectra of the synthesized macrolides as well as their rearranged isomers obtained during ring-closing metathesis showed that it is possible to assign the location of the double bond in an unsaturated macrolide on the basis of its EI mass spectrum. The occurrence of characteristic ions can be explained by the fragmentation pathway proposed in the article. In contrast, the localization of a double bond in many aliphatic open-chain compounds like alkenes, alcohols or acetates, important structural classes of pheromones, is usually not possible from an EI mass spectrum. In the article, we present the synthesis and for the first time elucidate the structure of macrolides from the frog family Hyperoliidae.
Complete Stereocontrol in the Synthesis of Harmonine and Novel Analogues Facilitated by a Grubbs Z-Selective Cross-Metathesis Catalyst
Abel, Steven-Alan G.,Olivier, Wesley J.,Pederson, Richard L.,Bissember, Alex C.,Smith, Jason A.
, p. 1815 - 1820 (2015/12/26)
(R)-Harmonine was synthesised in 15% overall yield via a six-step sequence exploiting a Z-selective cross-metathesis reaction as its centrepiece. By this strategy, the cis-olefin present in the target could be installed exclusively. The use of an alcohol and an ester as the amine precursors was crucial for isolating the cross-metathesis product from the self-metathesis products. This method was also used to prepare two novel analogues of harmonine.
