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Twonew pyrrolizidine alkaloids, ideamines A and B, together with other analogs (lycopsamine and parsonsine) were isolated in the TV-oxide forms from adult bodies of the Apocynaceae-feeding danaine butterfly, Idea leuconoe. Ideamine A was characterized as a homolog of lycopsamine, in which the viridifloric acid moiety was replaced by a 2-ethyl-2,3-dihydroxybutanoic moiety. Likewise, ideamine Bwas identified as a nor-derivative of parsonsine, in whichthe trachelanthic acid moiety was replaced by a 2-ethyl-2,3-dihydroxybutanoic moiety diastereomeric to the necic acid from ideamine A. Idea leuconoe Erichson is a large danaine butterfly whose larvae feed exclusively on the plant, Parsonsia laevigata Alston (Apocynaceae), in the Ryukyu Islands of Japan. Wehave isolated four pyrrolizidine alkaloids, both from the insect (adult bodies and eggs) and from the host plant, demonstrating the acquisition of the alkaloids directly from the larval host in this species.1} These alkaloids were found predominantly as TV-oxides in the insect tissues as well as in the plants. We report here the identification of the alkaloid components, which were isolated from the bodies of /. leuconoe, including two new analogs, ideamine A and B JV-oxides. Four alkaloid components (1-4) were isolated from an extract of laboratory-reared /. leuconoe adults by reverse-phase liquid chromatography.1} The molecular weights of compounds 1^1 were determined to be 301, 315, 441 and 455, respectively, from the

Two chalcone tetramers were isolated as inhibitors of Epstein-Barr virus (EBV)-activation induced by a tumor promoter, teleocidin B-4, from a medicinal plant in tropical west Africa, Lophira alata (Ochnaceae). One of them was identified as lophirachalcone. The other, named alatachalcone, was new, and the structure was determined by spectral properties. Both compounds also showed potent inhibitory activities against teleocidin B-4-induced inflammation on mouse ear. In an initiation-promotion experiment on mouse skin, alatachalcone (16 nmol) significantly inhibited tumor promotion caused by 12-O-tetradecanoylphorbol-13-acetate (TPA, 1.6 nmol).

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