Acta Cryst. (2004). C60, o833-o835 [doi:10.1107/S0108270104024291]
Abstract: Candibirin A [systematic name: 9,9'-(1,4-dioxane-2,5-diyldimethylenedioxy)di(7H-furo[3,2-g]chromen-7-one)], a new furanocoumarin dimer, was isolated from Heracleum candicans WALL. 1H NMR and MS spectra had indicated that the title compound was a dimer of heraclenin or heraclenol, but the linkage structure and its chirality were undetermined. The dioxane linkage, having the R,R configuration, has now been elucidated from dimethyl sulfoxide-solvated crystals, C32H28O10·2C2H6OS. Candibirin A is thus a dimerization product from heraclenin formed by reaction at the epoxy group. Dimethylformamide-solvated crystals, C32H28O10·C3H7NO, adopt a different conformation, with a folded structure that differs from the extended structure in the dimethyl sulfoxide solvate. However, the puckering of the dioxane linker unit is very similar in the two conformers. This result shows that the rotation of the ether bonds, in the linker between the furanocoumarin and dioxane moieties, causes the conformational flexibility of (I
Formula: C32H28O10·2C2H6OS and C32H28O10·C3H7NO
Online 31 October 2004
 |   Structure factor file (CIF format) (374.8 kbytes) |
| Structure factor file (CIF format) (172.4 kbytes) |
To open or display or play some files, you may need to set your browser up to use the appropriate software. See the full list of file types for an explanation of the different file types and their related mime types and, where available links to sites from where the appropriate software may be obtained.
The download button will force most browsers to prompt for a file name to store the data on your hard disk.
Where possible, images are represented by thumbnails.
Copyright © International Union of Crystallography
IUCr Webmaster