Triterpenes crystal structure

Shao, H., He, X., Achnine, L., Blount, J.W., Dixon, R.A. and Wang, X., Crystal structures of a multifunctional triterpene/flavonoid glycosyltransferase from Medicago truncatula. The Plant Cell, 2005, 17, 3141-3154. 

W. Massa, Kristallstrukturbestimmung, 2 edn, B.G. Teubner, Stuttgart, 1996. Crystal Structure of a Triterpene... 

The chemical study M. amazonica roots [81] conducted to the identification of seven new phenolic triterpenes, besides the two new celastroloids discussed above. The structure of compound (83), isolated as yellow crystals, was determined by spectroscopy. HREIMS indicated a molecular formula C28H34O6, and it showed IR absorption bands for carbonyl (1685, 1720 cm 1) and hydroxyl (3550 cm 1). 13C-NMR experiments indicated a phenolic triterpene related to 6-oxo-tingenol [85]. 

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