The water-soluble extract from a Paraguayan natural medicine, Nangapiry, the leaves of Eugenia uniflora L. (Myrtaceae), which has been used as an antidiabetic agent, was found to show inhibitory activities on the increase of plasma glucose level in the sucrose tolerance test (STT) conducted with mice. The portion adsorbed on a cation exchange resin was also found to inhibit a-glucosidases. From the active portion, two new active compounds named uniflorines A ( 1 ) and B ( 2 ) and known (+)-(3a, 4a, 5ß)-1-methylpiperidine-3, 4, 5-triol ( 3 ) were isolated. The structures of uniflorines A and B were determined as (-)-(1S, 2R, 6S, 7R, 8R, 8aR)-1,2,6,7,8-pentahydroxyindolizidine and (+)-(1S, 2R, 5R, 7R, 8S, 8aS)-1,2,5,7,8-pentahydroxyindolizidine by spectral means, respectively.

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Fusion of fagaronine (1) afforded N-demethyl fagaronine (2) and two minor desmethyl products. Through examination of spectral properties and derivatization, the structures were deduced to be 3, a tetramethoxy derivative, and 5, a derivative bearing a hydroxy (rather than a methoxy) group at position-8. Acetylation of 2 afforded a monoacetate derivative (4), and similarly, a diacetate (6) was produced from 5. Compounds 2-6 were substantially less cytotoxic than 1, as judged by KB or P-388 cell culture assays, supporting the functional importance of the quaternary nitrogen atom. The results obtained to date for fagaronine in tumor panel-testing are also presented, and the marginal cytotoxic activity demonstrated by compounds 5 and 6 against cultured P-388 cells is discussed in terms of mechanisms of action of the parent compound.

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Three new lanostanoids--ganodermenonol (1), ganodermadiol (2), and ganodermatriol (3) [isolated as its triacetate derivative (3a)]--were isolated from the MeOH extract of Ganoderma lucidum, together with ergosterol and its peroxide. The new compounds were identified as 26-hydroxy-5 alpha-lanosta-7,9(11),24-trien-3-one (1), 5 alpha-lanosta-7,9(11),24-triene-3 beta, 26-diol (2), and 5 alpha-lanosta-7,9(11),24-triene-3 beta, 26,27-triol (3) by their respective spectral data.

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