Date Published: June 01, 2010
Publisher: International Union of Crystallography
Author(s): Chanin Sarigaputi, Thapong Teerawatananond, Somchai Pengpreecha, Nongnuj Muangsin, Khanitha Pudhom.
The title compound (also known as phragmalin triacetate), C35H42O14, is a phragmalin-type limonoid extracted from X. rumphii. The molecule consists of eight rings with the orthoacetate group bridged at positions 1, 8 and 9. The two five-carbocyclic rings (A1 and A2) and the dioxolane ring (G) adopt a distorted envelope conformation. The 1,3-dioxane ring (E) exists in a chair conformation. The six-carbocyclic rings (B and C) exhibit a twisted-boat conformation. The lactone ring has a half-chair conformation and the furan ring is planar (r.m.s. deviation = 0.002 Å). Rings A1/B, A2/B, B/C, C/D and C/G are all cis-fused. The two acetoxy groups attached to ring B and the furan ring attached to the lactone ring are in equatorial positions. The porous crystal packing exhibits voids of 688 Å3 and weak intermolecular C—H⋯O interactions. The absolute configuration was assigned on the basis of literature data.
For background to the structures of limonoids and their activities, see: Koul et al. (2004 ▶); Cui et al. (2005 ▶); Pudhom et al. (2009 ▶). For related structures and the assignment of the absolute configuration, see: Wu et al. (2004 ▶); Fan et al. (2007 ▶). For puckering parameters, see: Cremer & Pople (1975 ▶).