RSS-Feed abonnieren
DOI: 10.1055/s-2006-959573
© Georg Thieme Verlag Stuttgart · New York
Improved Access to Highly Unsaturated Skin Irritants of the Daphnane Type from Latex of Excoecaria oppositifolia 1
1 Part IV in the series “Medicinal plants of Euphorbiaceae occurring and utilized in Thailand”. For part III, see Ref. (1)Publikationsverlauf
1994
1994
Publikationsdatum:
05. Januar 2007 (online)
Abstract
A new and more efficient procedure was developed to obtain 5β-hydroxyresiniferonol-6α,7α-epoxide-9,13,14-ortho(2,4,6-decatrienoate) [Excoecaria factor 01] by alkaline transesterification of corresponding 20-ester(s) genuinely present in latex of Excoecaria oppositifolia. It was obtained in a 10-fold better yield than previously, probably due to speeding up the separation procedures of the sensitive compound. 01 is an appropriate starting material for the preparation of the daphnane prototype irritant and tumor-promoting orthoester simplexin (SIM) especially of a multiple tritium-labeled form thereof. Moreover, a new Excoecaria factor 03, i.e. the 9,13,14-ortho(2,4,6,8-hexadecatetraenoate) of 5β,12β-dihydroxyresiniferonol-6α,7α-epoxide was isolated after alkaline transesterification of a TLC-uniform fraction, composed of corresponding 20-ester(s).
Key words
Excoecaria oppositifolia - Euphorbiaceae - daphnane orthoesters