Absolute configuration of isovouacapenol C

作者：Fun Hoong Kun^*; Yodsaoue Orapun; Karalai Chatchanok; Chantrapromma Suchada

来源：Acta Crystallographica Section E-Structure Reports Online, 2010, 66(8): O2059-U1585.

DOI：10.1107/S1600536810028023

The title compound, C27H34O5 {systematic name: (4aR,5R,6R,6aS,7R,11aS,11bR)-4a,6-dihydroxy-4,4,7,11b-tetramethyl-1,2,3,4,4a,5,6,6a,7,11,11a,11b-dodecahydrophenanthro[3,2-b]furan-5-yl benzoate}, is a cassane furanoditerpene, which was isolated from the roots of Caesalpinia pulcherrima. The three cyclohexane rings are trans fused: two of these are in chair conformations with the third in a twisted half-chair conformation, whereas the furan ring is almost planar (r.m.s. deviation = 0.003 A). An intramolecular C-H...O interaction generates an S(6) ring. The absolute configurations of the stereogenic centres at positions 4a, 5, 6, 6a, 7, 11a and 11b are R, R, R, S, R, S and R, respectively. In the crystal, molecules are linked into infinite chains along [010] by O-H...O hydrogen bonds. C...O [3.306 (2)-3.347 (2) A] short contacts and C-H...pi interactions also occur.

• 出版日期2010-8