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A pair of sulfonated diarylheptanoid epimers from Kaempferia galanga
Fang-Lin Wang1, Jian-Guang Luo, Xiao-Bing Wang
1Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing 210009, China.
Aim:
To discover new bioactive constituents from Kaempferia galanga L. (Zingiberaceae).
Methods:
The extract of K. galanga was divided into the chloroform and water-soluble portions. The latter fraction was successively subjected to column chromatography over a D101 macroporous adsorption resin, MCI, Sephadex LH-20, and preparative HPLC to obtain two compounds.
Results:
Two novel sulfonated diarylheptanoid epimers, namely kaempsulfonic acids A (1) and B (2), were isolated from the rhizomes of K. galanga. Their structures were established by analysis of spectroscopic data. The absolute configurations of 1 and 2 were determined by the comparison of experimental electronic circular dichroism (ECD) spectroscopy and the computational calculation method, combined with Mo2(OAc)4 induced circular dichroism (ICD).
Conclusion:
The isolates 1 and 2 are new compounds and their absolute configurations were determined for the first time.
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