Kimiko Nakano

Glycosides of ergosterol derivatives from Hericum erinacens

Abstract A new glycoside of ergosta-7,22-diene-3,5,6-triol was isolated from the dry fruiting body of Hericum erinacens and the structure was established by chemical and spectroscopic means. Six ergosterol derivatives were also isolated from H. erinacens .

Triterpenoid inhibitors of interleukin-1 secretion and tumour-promotion from Tripterygium wilfordii var. Regelii

Abstract Three new triterpenoids, 2,3,22β-trihydroxy-21-oxo-24, 29-nor-D:A-friedooleana-1,3,5(10)-triene, 2α, 6β-dihydroxy-3-oxo-24-nor-D:A-friedooleana-4-ene-29-oic acid and 2,3,7-trihydroxy-6-oxo-24-nor-D:A-friedooleana-1,3,5(10), 7-tetraene-29-oic acid, named regeol A, B and C, and nine known triterpenoides were isolated from T. wilfordii var. regelii . Their structures were established on the basis of the chemical reactions and spectroscopic evidence. Isolated compounds and derivatives were observed to inhibit Epstein-Barr virus early antigen activation and showed potent inhibitory activities against interleukin-1α and β release from human peripheral mononuclear cells.

Tripterygium wilfordii var. regelii which are interleukin-1 inhibitors

Abstract Seven new quinoide-type diterpenes were isolated from the stems of Tripterygium wilfordii var. regelii and their structures were established on the basis of spectroscopic and chemical evidence. The isolated compounds showed extremely potent inhibitory activities against interleukin-lα and β releases for human peripheral mononticlear cells.

Four kaempferol glycosides from leaves of Cinnamomum sieboldii

Abstract Four flavonol glycosides were isolated from Cinnamomum sieboldii and characterized as kaempferol 7- O -α- l -rhamnopyranosides having 3- O -α- l -rhamnopyranosyl, 3- O -α- l -arabinofuranosyl, 3- O -β- d - apiofuranosyl-(1→2)-α- l -arabinofuranosyl and 3- O -β- d -glucopyranosyl-(1→ 3)-α- l -rhamnopyranosyl residues, respectively. The latter three are new compounds.

12-Hydroxy steroidal glycosides from the caudex of Yucca gloriosa

Eight new steroidal glycosides, tentatively named YS-VI, -VII, -VIII, -IX, -X, -XI, -XII and -XIII were isolated from the caudex of Yucca gloriosa along with P-1, YG-2 and YG-3 previously obtained from flowers. The structures of five of these compounds were elucidated as mexogenin 3-O-beta-D-glucopyranosyl-(1----2)-beta-D-galactopyranoside (YS-VI), gloriogenin 3-O-beta-D-glucopyranosyl-(1----2)-[beta- D-glucopyranosyl-(1----3)]-beta-D-glucopyranoside (YS-VII) and 3-O-beta-D-glucopyranosyl-(1----2)-[beta-D-glucopyranosyl)-(1----3)]- beta-D-galactopyranoside (YS-VIII), manogenin 3-O-beta-lycotetraoside (YS-IX) and 3-O-alpha-L-rhamnopyranosyl-beta-lycotetraoside (YS-X), respectively, on the basis of chemical and spectral evidence.

The steroidal glycosides of the flowers of Yucca gloriosa

Abstract Four steroidal compounds were isolated from the fresh flowers of Yucca gloriosa and their structures were elucidated as tigogenin 3-O-β- d -xylopyranosyl-β-lycotetraoside, gitogenin 3-O-β- d -xylopyranosyl-β-lycotetraoside, gitogenin 3-O-α- l -rhamnopyranosyl-β-lycotetraoside and proto-type of gitogenin 3-O-β- d -xylopyranosyl-β-lycotetraoside, on the basis of physical and chemical investigations.

Structures of sesquiterpene polyol esters from Tripterygium wilfordii var. Regelii

Abstract Seven new dihydroagarofuran derivatives, triptogelin E-1, E-2, E-3, E-4, G-1, C-4 and D-1 have been isolated from T. wilfordii var. regelii. Their structures have been established on the basis of spectroscopic and chemical evidence.

A polyoxygenated steroid fromLasiosphaera nipponica

Abstract A new polyoxygenated ergosterol derivative, as well as three known steroids and a calvatic acid derivative were isolated fromLasiosphaera nipponica. The structures of these compounds were established by chemical and spectroscopic means.

Terpenoids in transformed root culture of Tripterygium wilfordii

Investigation of a hairy root culture of Tripterygium wilfordii var. regelii transformed with Agrobacterium rhizogenes resulted in the isolation of new diterpenoid and sesquiterpenoid together with known triterpenoids. These structures were determined by spectroscopic analyses.

A novel epoxy-triterpene and nortriterpene from callus cultures of Tripterygium wilfordii

Abstract The callus of T. wilfordii var. regelii afforded three new pentacyclic triterpenes D:B-friedoolean-3-ol-5,6-epoxy-29-oic acid, 3α, 22α-dihydroxy-olean-12-en-29-oic acid and 24, 29-dinor D:A-friedoolean 4-en-2β, 22β-dihydroxy-3, 21-dion, named triptocallic acid C, D and triptocalline A, respectively, in addition to five known triterpenes. These structures were determined by spectroscopic analyses.