Yasunori Yaoita

Secoiridoid glycosides from the flower buds of Lonicera japonica

Two secoiridoid glycosides, loniceracetalides A and B, were isolated in very small amounts, together with 10 known iridoid glycosides, from the flower buds of Lonicera japonica. The structures of loniceracetalides A and B were determined by spectroscopic analysis.

Triterpenoids from Gentiana scabra

Five triterpenoids, (20S)-dammara-13(17),24-dien-3-one, (20R)-dammara-13(17),24-dien-3-one, chirat-16-en-3-one, chirat-17(22)-en-3-one and 17beta,21beta-epoxyhopan-3-one, were isolated from the rhizomes and roots of Gentiana scabra together with five known ones, chiratenol, hop-17(21)-en-3-one, hop-17(21)-en-3beta-ol, lupeol and alpha-amyrin. The structures of new compounds were elucidated on the basis of spectroscopic studies.

Seco-eremophilane derivatives from rhizomes of Petasites japonicus

Two new seco-eremophilane derivatives, secoeremopetasitolides A and B, were isolated from the dried rhizomes of Petasites japonicus. The structures of the new compounds were determined by spectroscopic evidence.

A new ceramide from Ramaria botrytis (Pers.) Ricken

A new ceramide, (2S,2′R,3R,4E,8E)-N-2′-hydroxyoctadecanoyl-2-amino-9-methyl-4,8-heptadecadiene-1,3-diol (1), was isolated together with four known sterols, 5α,6α-epoxy-3β-hydroxy-(22E)-ergosta-8(14),22-dien-7-one (2), ergosterol peroxide (3), cerevisterol (4) and 9α-hydroxycerevisterol (5), from the fruiting bodies of Ramaria botrytis (Pers.) Ricken (Ramariaceae). The structure of the new compound was elucidated based on spectral data.

Eremopetasidione, a nor-sesquiterpenoid from the rhizomes ofPetasites japonicus

Abstract A new nor-sesquiterpenoid, eremopetasidione, was isolated from the dried rhizomes of Petasites japonicus . The structure of the new compound was det

Glycosides from whole plants of Glechoma hederacea L

From dried whole plants of Glechoma hederacea L. (Labiatae), seven known glycosides were isolated and identified: (6R,7E,9R)-megastigma-4,7-dien-3-one 9-O-β-d-glucopyranoside (1), apigenin 7-O-neohesperidoside (2), chrysoeriol 7-O-neohesperidoside (3), (+)-pinoresinol 4,4′-bis-O-β-d-glucopyranoside (4), (+)-syringaresinol 4,4′-bis-O-β-d-glucopyranoside (5), (+)-lariciresinol 4,4′-bis-O-β-d-glucopyranoside (6), and (7R,8R)-threo-7,9,9′-trihydroxy-3,3′-dimethoxy-8-O-4′-neolignan 4-O-β-d-glucopyranoside (7).

Secoiridoid glycosides from the leaves of Hydrangea macrophylla subsp. serrata

Seven secoiridoid glycosides, secologanin dimethyl acetal (1), n-butyl vogeloside (2), n-butyl epi-vogeloside (3), (7R)-n-butyl morroniside (4), hydrangenoside A (5), hydrangenoside C (6), and hydrangenoside A dimethyl acetal (7), have been isolated from the leaves of Hydrangea macrophylla subsp. serrata (Thunb.) Makino (Saxifragaceae). The structures were elucidated on the basis of spectral data.

Constituents of the leaves and roots of Ligularia stenocephala MATSUM. et KOIDZ.

Constituents of the leaves and roots of Ligularia stenocephala MATSUM. et KOIDZ. (Compositae) were investigated. Three compounds, (2E,6E,10E,14E,18E)-2,6,10,15,19,23-hexamethyl-2,6,10,14,18,22-tetracosahexaen-1-ol, (3E,6E,10E,14E,18E)-2,6,10,15,19,23-hexamethyl-3,6,10,14,18,22-tetracosahexaen-2-ol and neophytadiene, were isolated from the leaves of L. stenocephala. Six compounds, 5-acetyl-6-hydroxy-2α-isopropenyl-3β-methoxy-2,3H-benzofuran, 3β-acetoxy-6-acetyl-5-hydroxy-2α-isopropenyl-2,3H-benzofuran, p-hydroxybenzaldehyde, vanillin, 4-hydroxyacetophenone and 4-hydroxy-3-methoxyacetophenone, were isolated from the roots of L. stenocephala. The structures were determined on the basis of spectral data.

Constituents of the roots of Ligularia dentata Hara

Nine known compounds, butyrospermol (1), lupeol (2), stigmast-4-en-3-one (3), stigmast-4-ene-3,6-dione (4), (+)-methyl abscisate (5), methyl indole-3-carboxylate (6), vanillin (7), methyl (E)-caffeate (8), and methyl (E)-ferulate (9), and two new compounds, methyl (E)-feruloylglycolate (10), and methyl-7,8-dihydro-(S)-7-methoxyferulate (11), have been isolated from the roots of Ligularia dentata Hara (Compositae). The structures were elucidated on the basis of spectral data.

Petasiphenone, a phenolic compound from rhizomes ofPetasites japonicus

Abstract A new phenolic compound, petasiphenone, was isolated from the dried rhizomes ofPetasites japonicus together with the known phenolic compound, peta