549-22-4Relevant articles and documents
General Synthetic Approach to Rotenoids via Stereospecific, Group-Selective 1,2-Rearrangement and Dual S N Ar Cyclizations of Aryl Fluorides
Matsuoka, Seiya,Nakamura, Kayo,Ohmori, Ken,Suzuki, Keisuke
, p. 1139 - 1156 (2019/02/26)
A general synthetic approach to rotenoids is described, featuring 1) stereospecific, group-selective 1,2-rearrangements of epoxy alcohols, and 2) S N Ar oxy-cyclizations of aryl fluorides. The common intermediate epoxyketone, en route to (-)-rotenone and (-)-deguelin, was prepared from d -araboascorbic acid in five steps. Also described is the conversion of (-)-deguelin into oxidized congeners, (-)-tephrosin and (+)-12a- epi -tephrosin.
Synthesis of trans-B/C-Rotenoids: X-Ray and NMR Data for cis- and trans-Forms of Isorotenone
Begley, Michael J.,Crombie, Leslie,Hadi, Hamid bin A.,Josephs, Jonathan L.
, p. 2605 - 2614 (2007/10/02)
Reduction of 6a,12a-didehydrorotenoids with diisobutylaluminium hydride gives clean 1,4-reduction leading to unstable trans-B/C-fusions, not previously known for enolisable rotenoids: they are epimerised to stable cis-forms under acid conditions.Applied initially to isorotenone, the method is extended to trans-B/C-deguelin, α-toxicarol, the 'core' rotenoid structure and the 6aS,12aR,5'R- and 6aR,12aS,5'R-rotenone stereoisomers. 1H and 13C NMR data are compared for the cis- and trans-forms and the geometry and conformations of the isorotenones are compared by X-ray analysis, providing insight into the reasons for the instability of the trans-forms.Reduction of the ridge-tile-like cis-isorotenone by sodium borohydride occurs from one face to give a cis-12α-hydroxy product, whilst the flatter trans-structure is attacked from both faces to give trans-12α- and 12β-hydroxy products.
Synthesis of Novel Labile Rotenoids with Unnatural trans-B/C Ring Systems
Begley, Michael J.,Crombie, Leslie,Hadi, A. Hamid bin A.,Josephs, Jonathan L.
, p. 204 - 205 (2007/10/02)
6a,12a-Dehydrorotenoids are cleanly reduced in 1,4-fashion by DIBAL to give rotenoids having the unstable, unnatural, trans-B/C fusion, readily epimerised by acid to the cis-forms: an X-ray structure for (+/-)-trans-isorotenone confirms the nature of the ring fusion.