New chalcone dimers from Caesalpinia ferrea Mart act as potent inhibitors of DNA topoisomerase II

S Ohira, K Takaya, T Mitsui, M Kido, K Kakumoto, K Hayashi, A Kuboki, H Tani, S Ikeda, M Iinuma, Y Akao, H Nozaki

Tetrahedron Letters

54

37

5052

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