Ayumi Ohsaki

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A new iridoid glycoside, citrifoside (1), and a new anthraquinone, 1,5,15-trimethylmorindol (2), together with 24 known compounds, were isolated from the leaves of Morinda citrifolia. The structures of the new compounds were elucidated by spectral data. 1,5,15-Trimethylmorindol (2) did not show significant cytotoxic activity by itself but showed(More)
Five new monoterpene indole alkaloids, naucleamides A-E (1-5), were isolated from the bark and wood of Nauclea latifolia, and the structures and relative stereochemistry were elucidated from the spectroscopic data. Naucleamide E (5) is a unique monoterpene indole alkaloid possessing a pentacyclic ring system with an amino acetal bridge.
Four known compounds have been isolated from the aerial parts of the Brazilian medicinal plant Pariparoba (Pothomorphe umbellata). They were an alkaloid, a flavone, a dihydrocalcone, and a steroid. The chemical structures were established to be N-benzoylmescaline, wogonin, uvangoletin, and beta-sitosterol glucoside using spectral methods. Among these(More)
Two new Erythrinan alkaloids, cristanines A and B (1, 2), were isolated from the bark of Erythrina crista-galli L. together with nine known Erythrinan alkaloids (3-5, 7-12) and an indole alkaloid (13). The structures of the compounds, cristanines A (1) and B (2), were elucidated by spectroscopic methods. Three of the twelve compounds isolated showed(More)
Brartemicin (1), a new trehalose-derived metabolite, was isolated from the culture broth of the actinomycete of the genus Nonomuraea. Its structure and absolute configuration were determined by spectroscopic analyses. The new compound inhibited the invasion of murine colon carcinoma 26-L5 cells with an IC(50) value of 0.39 microM in a(More)
An indole alkaloid (hypaphorine (1)) was isolated from Brazilian medicinal plant, Erythrina velutina (Leguminosae). This compound was investigated for sleep promoting effects in mice, and the results showed that it significantly increased non-rapid eye movement (NREM) sleep time during the first hour after its administration. The NREM sleep time was(More)
A selective potent anti-Helicobacter pylori isoflavone was isolated from a Brazilian Medicinal Plant, Myroxylon peruiferum. The isolation bioassay-guided and the characterization of an active anti-H. pylori constituent was performed using the methanol extract of plant of minute amount. The active compound was identified as cabreuvin (1), an isoflavone(More)
Two new cembrane diterpenoids with an eight-membered lactone ring, echinodolides A (1) and B (2), were isolated from the leaves of the Brazilian medicinal plant Echinodorus macrophyllus ("Chapéu-de-couro"), and the structures and relative stereochemistry were elucidated from their spectroscopic data.
Four new oxindole alkaloids, paratunamides A-D (1-4), containing a secologanin unit, were isolated from the bark of Cinnamodendron axillare, and their structures and relative configurations were elucidated by spectroscopic data. The absolute configuration at C-7 in 1-4 was assigned as S, S, R, and S, respectively, on the basis of the CD spectra.
Kiusianins A-D (1-4) were isolated from the leaves of a Japanese endemic plant, Tilia kiusiana, together with 14 known compounds. The structures of a new lanostane-type triterpenoid 1 and three new cholestane-type sterols 2-4 were elucidated by spectroscopic methods, including two dimensional (2D) NMR. All the compounds isolated were evaluated for their(More)