(1S,5R,7R,30S)-14-De-oxy-isogarcinol

Abstract

The title compound, C(38)H(50)O(5) {systematic name: 10-(3-hy-droxy-benzo-yl)-2,2,7,7-tetra-methyl-3,6,8-tris-(3-methyl-but-2-en-yl)-3,4,4a,5,6,7-hexa-hydro-4a,8-methano-2H-cyclo-octa-[b]pyran-9,11(8H)-dione}, is a polyisoprenylated benzophenone, isolated for the first time from the fruits of Garcinia indica during our investigation of bioactive compounds from this plant and their large-scale extraction. The relative configuration of the title compound was chosen based on comparison of its spectroscopic and optical rotation data with that of the isomorphous and isostructural compound isogarcinol, whose absolute configuration is known. The crystal packing features O-H⋯O hydrogen bonds. A Cambridge Structural Database analysis revealed that the crystal structure reported here is isomorphous and isostructural with that of isogarcinol.

Fig. 1.

Chemical structures of garcinol, isogarcinol, 14-deoxy isogarcinol (1) and polyprenylated acylphloroglucinol derivative (2)

Fig. 2.

(a) Molecular conformation in crystals and atom labeling for 1. The thermal ellipsoids are shown at 30% probability level. (b) Overlay of the crystal state conformations of 1 (yellow) and isogarcinol (purple; CSD refcode BEVHIT01; Marti et al., 2009). RMSD = 0.025 Å for the superposed atoms. Hydrogen atoms are shown only for the hydroxyl groups.

Fig. 3.

Intermolecular hydrogen bonding in the crystals of 1 (left) and isogarcinol (right, CSD refcode BEVHIT01; Marti et al., 2009)

Fig. 4.

Packing of molecules viewed down the crystallographic b axis for (a) 1 and (b) isogarcinol.

Fig. 5.

Overlay of the molecular conformations of 1 (yellow) and 14-methoxy isogarcinol (purple; (CSD refcode JISXEP; Marti et al., 2009).RMSD = 0.072 Å for the superposed atoms. Hydrogen atoms are shown only for the hydroxyl groups.