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A biologically active quinone that exhibits a growth-inhibitory effect on rat liver cancer cells was isolated from the nest of a social wasp, Vespa simillima (Vespinae, Vespidae). The structure was unambiguously determined by NMR and synthetic experiments and identified as being 7,8-seco-para-ferruginone. The synthetic quinone showed potent growth-inhibitory effects on rat hepatoma cells (IC50 value=1.9 microM). Morphological analyses of dRLh84 cells using the synthetic compound were tested. Chromatin coagulation was induced by the synthetic compound at 31.6 muM.

Four novel peptides, polistes-mastoparan-R1, 2, 3, and polistes-protonectin, were isolated from the venom of a paper wasp, Polistes rothneyi iwatai. MALDI-TOF MS analysis of a small amount of the crude venom gave six molecular-related ion peaks. Among them, m/z 1565 was expected to be a novel peptide. Purification of the crude venom by HPLC gave two known kinins, Thr6-bradykinin and Ala-Arg-Thr6-bradykinin, and four novel peptides named polistes-mastoparan-R1, 2, and 3, and polistes-protonectin. Polistes-mastoparan-R1, 2, and 3 (Pm-R) were tetradecapeptides that possess high sequence homology with that of mastoparan. The sequence of polistes-protonectin was similar to that of protonectin isolated from a Brazilian paper wasp. Histamine-releasing activities of Pm-R1, 2, and 3 were more potent than that of mastoparan. Polistes-protonectin exhibited the most potent hemolytic activity in comparison with the four novel peptides and mastoparan.

With the aim of obtaining a porphyrin derivative useful for diagnosis and therapy of cancer, fluorine analogues of protoporphyrin, in which the vinyl group(s) were replaced by difluorovinyl group(s), were synthesized by the reaction of the formylporphyrins with sodium chlorodifluoroacetate in the presence of triphenylphosphine. Some improvements in the reported procedures for the synthesis of formylporphyrins are also described. Preliminary results of biological tests of the products showed that 8(2),8(2)-difluoroprotoporphyrin accumulates to gastric cancer more selectively than other fluorine analogues and that 3(2),3(2),8(2),8(2)-tetrafluoroprotoporphyrin is taken up by rat hepatoma cells more readily than the others.

Stereoselective functionalization at C-9 of retinal based on the use of the C 4 +X-unit is described. A sequential linkage of C 4 +X-units (X=Cl, Br, and I) with ylide 8 (C 10 ) and phosphonate 12 (C 5 )selectively gave 9-trans-19-nor-9-Cl, Br, and I-retinal derivatives.

A new stereoselective route to γ-butyrolactones such as (+)-trans-whisky and (+)-trans-cognac lactones (1a, b) has been developed by a combination of three key reactions : diastereoselective nucleophilic addition of thiophenol, cleavage of chiral N-acylsultam via thioester, and intramolecular displacement of the sulfonium group with carboxylate anion.

A concerted method for the stereospecific addition of thiophenol to α, β-unsaturated esters 1 and 3 has been developed. This provides a convenient route for the stereo-selective preparation of less available Z__--α, β-unsaturated esters and lactones 3.