65018-15-7Relevant academic research and scientific papers
Acid-promoted opening of 4,5- and 3,4-epoxy eudesmane scaffolds from α-isocostic acid
Zaki, Mohamed,Tebbaa, Mohammed,Hiebel, Marie-Aude,Benharref, Ahmed,Akssira, Mohamed,Berteina-Raboin, Sabine
, p. 2035 - 2042 (2015/03/30)
The acid-catalyzed rearrangement of epoxide 3a and 8a derived from sesquiterpernic isocostic acid (1), the main component of Dittrichia viscosa, was studied using Lewis and Br?nsted acids. Several new compounds were obtained with different selectivities depending on the catalyst used. These compounds were fully characterized by spectroscopic methods, and mechanistic explanations for their formation are proposed.
Germacrenes from fresh costus roots
De Kraker, Jan-Willem,Franssen, Maurice C.R,De Groot, Aede,Shibata, Toshiro,Bouwmeester, Harro J
, p. 481 - 487 (2007/10/03)
Four germacrenes, previously shown to be intermediates in sesquiterpene lactone biosynthesis, were isolated from fresh costus roots (Saussurea lappa). The structures of (+)-germacrene A, germacra-1(10),4,11(13)-trien-12-ol, germacra-1(10),4,11(13)-trien-12-al, and germacra-1(10),4,11(13)-trien-12-oic acid were deduced by a combination of spectral data and chemical transformations. Heating of these compounds yields (-)-β-elemene, (-)-elema-1,3,11(13)-trien-12-ol, (-)-elema-1,3,11(13)-trien-12-al, and elema-1,3,11(13)-trien12-oic acid respectively, in addition to small amounts of their diastereomers. Acid induced cyclisation of the germacrenes yields selinene, costol, costal, and costic acid respectively. It is highly probable that the elemenes reported in literature for costus root oil are artefacts.
THE TOTAL SYNTHESIS OF (+/-)-α-COSTAL
Liu, H. J.,Wynn, H.
, p. 4843 - 4846 (2007/10/02)
The structure of α-costal (1) has been confirmed by an unequivocal total synthesis which makes use of S-t-butyl cyanothiolacetate to facilitate the incorporation of the labile acrolein unit present in the naturally occuring aldehyde.
