10α-Hydroxy-13-{[4-(4-methoxyphenyl)piperazin-1-yl]methyl}-4,9-dimethyl-3,8,15-trioxatetracyclo[10.3.0.02,4.07,9]pentadecan-14-one

Abstract

The title compound, C26H36N2O6, was synthesized from 9α-hydroxyparthenolide (9α-hydroxy-4,8-dimethyl-12-methylen-3,14-dioxa-tricyclo[9.3.0.02,4]tetradec-7-en-13-one), which was isolated from the chloroform extract of the aerial parts of Anvillea radiata. The molecule is built up from fused five- and ten-membered rings with two additional epoxy ring systems and a methoxyphenylpiperazine group as a substituent. The ten-membered ring adopts an approximate chair–chair conformation, while the piperazine ring displays a chair conformation and the five-membered ring shows an envelope conformation with the C atom closest to the hydroxy group forming the flap. The molecular conformation is determined by an O—H...N hydrogen bond between the hydroxy group and a piperazine N atom. The crystal structure is built up by weak C—H...O interactions.