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Choerosponins A and B, Two New Cytotoxic Bridged-Ring Ketones and the Determination of Their Absolute Configurations.

ABSTRACT: Bioactivity-directed fractionation of antitumor compounds from the stem barks of Choerospondias axillaries (Roxb.) Burtt et Hill (Anacardiaceae) afforded two new cytotoxic bridged-ring ketones, choerosponins A (1) and B (2), and their structures were elucidated by spectroscopic methods; their stereochemistry was determined by NOE difference experiments, CD spectra and the modified Mosher's method. Compound 1 has a rare dioxatricyclo skeleton. Flow cytometry and SRB methods were employed to evaluate the antitumor activity of the two compounds against tsFT210, HCT-15, HeLa, A2780 and MCF-7 cell lines, and both of them showed strong cytotoxicity. MTT and paper disc methods were also used to evaluate their anti-hypoxia and antibacterial activities, and both of them showed no apparent activities.

SUBMITTER: Li CW

PROVIDER: S-EPMC6154574 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Choerosponins A and B, Two New Cytotoxic Bridged-Ring Ketones and the Determination of Their Absolute Configurations.

Li Chang-Wei CW Han Bing B Cai Bing B Cui Cheng-Bin CB

Molecules (Basel, Switzerland) 20170327 4

Bioactivity-directed fractionation of antitumor compounds from the stem barks of Choerospondias axillaries (Roxb.) Burtt et Hill (Anacardiaceae) afforded two new cytotoxic bridged-ring ketones, choerosponins A (1) and B (2), and their structures were elucidated by spectroscopic methods; their stereochemistry was determined by NOE difference experiments, CD spectra and the modified Mosher's method. Compound 1 has a rare dioxatricyclo skeleton. Flow cytometry and SRB me ...[more]

PMID: 28346393

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