4-Hydroxy-4,6a,6b,9,9,12a,14b-heptamethylperhydropicen-3-one hemihydrate isolated from Adiantum incisum

Hussain, A.; Siddiqui, H.L.; Zia-ur-Rehman, M.; Elsegood, M.R.J.; Mhan, K.

doi:10.1107/S1600536807064021

Acta Crystallographica Section E

Structure Reports Online

Volume 64, Part 1 (January 2008)

organic compounds

Acta Cryst. (2008). E64, o264 [ doi:10.1107/S1600536807064021 ]

4-Hydroxy-4,6a,6b,9,9,12a,14b-heptamethylperhydropicen-3-one hemihydrate isolated from Adiantum incisum

A. Hussain, H. L. Siddiqui, M. Zia-ur-Rehman, M. R. J. Elsegood and K. M. Khan

Abstract: The title compound, C₂₉H₄₈O₂·0.5H₂O, is a triterpenoid isolated from the stems and rhizomes of Adiantum incisum. The basic skeleton of the molecule contains five six-membered rings, all adopting chair conformations, bearing a total of seven methyl, one hydroxyl and a keto group. There are two molecules of the triterpene and one water molecule of crystallization in the asymmetric unit. The two unique triterpenoid molecules hydrogen-bond directly via an O-HO=C interaction, and are also bridged by the water molecule. The water also bridges to another pair of hydrogen-bonded triterpenoid molecules.