Tsuyoshi Ikeda

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Two new steroid glycosides, named trikamsterosides A and B, and a new sesquiterpenoid glycoside named trikamsesuquiside A were isolated from the underground parts of Trillium kamtschaticum PALL. along with 18 known compounds comprising 12 steroids, one sesquiterpenoid glycoside, one phenylpropanoid, one flavonoid glycoside, and three phenylpropanoid sucrose(More)
From the unripe fruits of Lo Han Kuo (Siraitia grosvenori), a Chinese medicinal plant, two new cucurbitane triterpene glycosides, 20-hydroxy-11-oxomogroside IA(1) (1) and 11-oxomogroside IIE (2), were isolated along with five known cucurbitane glycosides, 11-oxomogroside IA(1) (3), mogroside IIE (4), mogroside III (5), mogroside IVA (6), and mogroside V(More)
Tumor-associated macrophages (TAM) of M2 phenotype promote tumor proliferation and are associated with a poor prognosis in patients with glioblastoma. We screened the natural compounds possessing an inhibitory effect on M2 polarization in human monocyte-derived macrophages. Among 130 purified natural compounds examined, corosolic acid significantly(More)
Because advanced glycation end product (AGE) inhibitors such as pyridoxamine significantly inhibit the development of retinopathy and neuropathy in the streptozotocin-induced diabetic rat, treatment with AGE inhibitors is believed to be a potential strategy for the prevention of lifestyle-related diseases such as diabetic complications. A crude extract of(More)
Unpolished rice black vinegar (kurozu), a traditional Japanese vinegar, is considered to have beneficial health effects. Kurozu is produced via a static fermentation process involving the saccharification of rice by Aspergillus oryzae, alcohol fermentation by Saccharomyces cerevisiae, and the oxidation of ethanol to acetic acid by acetic acid bacteria such(More)
Notoamides O-R were isolated from a marine-derived Aspergillus sp. Notoamide O possesses a novel hemiacetal/hemiaminal ether functionality hitherto unknown among this family of prenylated indole alkaloids. The structure represents an unusual branch point for the oxidative modification of other members in the family of prenylated indole alkaloids in the(More)
A new phenyldihydronaphthalene-type lignan, vitedoin A (1), a new phenylnaphthalene-type lignan alkaloid, vitedoamine A (2), and a new trinorlabdane-type diterpene, vitedoin B (3), were isolated from the seeds of Vitex negundo along with five known lignan derivatives (4-8). Their chemical structures were determined mainly on the basis of NMR and MS data.(More)
Two furostane-type steroidal oligoglycosides (1, 2), together with a new pregnane-type oligoglycoside (3), were obtained from the seeds of Allium tuberosum ROTTLER. On the basis of spectroscopic analysis, the structures of three new oligoglycosides (1-3) were elucidated as 26-O-beta-D-glucopyranosyl-(25R)-3beta,22xi,26-trihydroxyl-5alpha-furostane(More)
The anti-herpes simplex virus type 1 (HSV-1) activity of 15 oleanan-type triterpenoides including glycyrrhizin and its sapogenol was examined and their structure-activity relationships were discussed. Although glycyrrhizin which exhibited in vivo efficacy against HSV-1 replication showed moderate in vitro anti-HSV-1 activity, its sapogenol, glycyrrhetic(More)
The root of Strobilanthes cusia BREMEK. (Acanthaceae), popularly known as Da-Ching-Yeh, has been commonly used in traditional Chinese medicine. It is used to treat influenza, epidemic cerebrospinal meningitis, encephalitis B, viral pneumonia, mumps, and severe acute respiratory syndrome (SARS). In this study, we found a new lignan glycoside (6) and two new(More)