• Archives of Pharmacal Research
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• v.19 no.6
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• pp.543-550
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• 1996

Analogues of $2(S)-5, 2^{l}, 5^{l}$-trihydroxy-7, 8-dimethoxyflavanone, a naturally-occurring compound, which had been reported to have potent antitumor activity, were synthesized and examined for the cytotoxicity against three cancer cell lines. Among the intermediate chalcones and synthetic 5-hydroxy-7, 8-dimethoxyflavanone analogues, $({\pm})2^{l}, 5^{l}-dibenzyloxy-5, 7, 8-trimethoxyflavanone$ exhibited about 2-8 times stronger activity than $2(S)-5, 2^{l}, 5^{l}$-trihydroxy-7, 8-dimethoxyflavanone against L1210, K562 and A549 cancer cell lines. In the structure-activity relationship, it is suggested that among analogues of 5-hydroxy-7, 8-dimethoxyflavanone, the existence of two oxygenated groups of para-relation at $C-2^{I} and C-5^{I}$ positions on flavanone B-ring, may be necessary to exhibit effective cytotoxic activity.

• Archives of Pharmacal Research
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• v.20 no.4
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• pp.368-371
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• 1997

In an effort to increase of the antitumor activity of 2(S)-$2^{I}$,$5^{I}$-trihydroxy-7, 8-dimethoxyflavanone isolated from Scutellaria indica, we synthesized its analogues, II, III and IV. They showed potent cytotoxicity in vitro against cancer cell lines, L1210, K562 and A549. On the basis of $ED_50$ values against the cancer cell lines, III exhibited about 2-7 times stronger activity than I against various cell lines. We tested the antitumor activity of the analogues against Sarcoma 180 cells in vivo and evaluated the structure-activity relationship. The antitumor activity appeared to be related to the hydrogen bond between carbonyl group at C-4 and hydroxyl group at C-5, in contrast to cytotoxic action.