Received 11 May 2009
Crystals of the title salt, C17H28NO3+·C4H3O4-, were obtained by reacting parthenolide with dimethylamine followed by conversion of the amine adduct into a water-soluble fumarate salt. Subsequent crystallization of the fumarate salt from water afforded colorless orthorhombic crystals. The amine addition is highly stereospecific yielding exclusively a single diastereomer with R-configuration at the newly formed C-11 chiral carbon. In the crystal, intermolecular O-HO and N-HO hydrogen bonds help to establish the packing.
Parthenolide (PTL) is a naturally occurring sesquiterpene lactone used in the treatment of fever, migraine headaches, rheumatoid arthritis, and also as an anti-inflammatory agent (Heptinstall et al. (1988). For the potent anti-tumor and cytotoxic properties of PTL, see: Crooks et al. (2007). The absolute stereochemistry of the C-11 chiral carbon is typical of such amine adducts of parthenolide, see: Nasim et al. (2007a,b). For bond-length data, see: Allen et al. (1987).
Data collection: APEX2 (Bruker-Nonius, 2006); cell refinement: SAINT (Bruker-Nonius, 2006); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 and local procedures.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HG2516 ).
This research work was supported by the Kentucky Lung Cancer Research Program.
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