Akira Ueno

Structures of sesquiterpenes from Curcuma longa

Abstract Five new sesquiterpenes, germacrone-13-al, 4-hydroxybisabola-2,10-diene-9-one, 4-methoxy-5-hydroxy-bisabola-2, 10-diene-9-one, 2,5-dihydroxybisabola-3,10-diene, and procurcumadiol were isolated along with curcumenone, dehydrocurdione, (4 S ,5 S )-germacrone-4,5-epoxide, bisabola-3,10-diene-2-one, α-turmerone, bisacumol, bisacurone, curcumenol, isoprocurcumenol, zedoaronediol, procurcumenol, epiprocurcumenol and 4,5-dihydroxy-bisabola-2, 10-diene. from Curcuma longa . The structures of the new compounds were determined and the stereochemistry of 4,5-dihydroxybisabola-2,10-diene were established by spectral methods.

Ionone and lignan glycosides from Epimedium diphyllum

Abstract From the aerial parts of Epimedium diphyllum, a new ionone derivative glucoside, icariside B8, two new lignan glycosides, icarisides E4 and E5 and a new phenylethanoid glucoside, icariside D2, have been isolated together with 20 known compounds. The structures of four new compounds were established by spectral and chemical evidence.

Phenylethanoid glycosides from Stachys officinalis

From the aerial parts of Stachys officinalis, six new phenylethanoid glycosides, named betonyosides A-F, and six known phenylethanoid glycosides, acetoside, acetoside isomer, campneosides II, forsythoside B and leucosceptoside B, were isolated and their structures were elucidated from spectroscopic and chemical evidence. Campneosides II were separated into two epimers.

Phenylethanoid glycosides from Plantago asiatica

Abstract Six new phenylethanoid glycosides, plantainosides A–F, were isolated from a water extract of the whole plants of Plantago asiatica together with eight known phenylethanoid glycosides. Their structures were determined on the basis of chemical and spectral evidence.

Lignan and terpene glycosides from Epimedium sagittatum

From the aerial parts of Epimedium sagittatum, four new lignans, icarisides E6, E7, icariols A1, A2, a new phenylethanoid, icariside D3, a new phenylpropanoid, icariside H1 and a new ionone derivative, icariside B9, have been isolated together with 20 known compounds. The structures of new compounds were established by spectral and chemical evidence.

Terpenic glycosides from Pluchea indica

Abstract Investigation of the aerial parts of Pluchea indica afforded five new terpenic glycosides, linaloyl glucoside, linaloyl apiosyl glucoside, 9-hydroxylinaloyl glucoside, plucheosides A and B, in addition to 15 known compounds. The structures of new compounds were elucidated on the basis of chemical and spectral data.

Phenylethanoid and lignan glycosides from Verbascum thapsus.

Verbascum thapsus afforded, in addition to three known phenylethanoid glycosides and four lignan ones, five new phenylethanoid glycosides and one new lignan glycoside. Structures of the compounds were elucidated by spectroscopic methods and chemical evidence.

Physalin and neophysalins from Physalis alkekengi var. francheti and their differentiation inducing activity

A methanol extract of Physalis alkekengi var. francheti showed a potent cell differentiation inducing activity toward mouse myeloid leukemia cell line (M1 cells). From the extract, a new physalin and two new neophysalins, 25,27-dihydro-4,7-didehydro-7-deoxyneophysalin A and 4,7-didehydroneophysalin B, were isolated along with physalin A, L and isophysalin B. The structures of physalins and neophysalins were determined by means of NMR, UV, IR and mass spectra. Of these compounds, physalin A showed potent cell differentiation inducing activity.

Development of a novel method for determination of acetyl-CoA:1-alkyl-sn-glycero-3-phosphocholine acetyltransferase activity and its application to screening for acetyltransferase inhibitors: Inhibition by magnolol and honokiol from Magnoliae cortex

A method was developed for determining the activity of acetyl-CoA:1-alkyl-sn-glycero-3-phosphocholine acetyltransferase (EC 2.3.1.67), a key enzyme in the biosynthesis of platelet-activating factor (PAF, 1-alkyl-2-acetyl-sn-glycero-3-phosphocholine). The assay involves measurement of the radioactivity in the trichloroacetic acid (TCA)-precipitated complex of radioactive product and albumin after incubation of 1-alkyl-sn-glycero-3-phosphocholine and [3H]acetyl-CoA with rat spleen microsomes or membrane fractions of human polymorphonuclear leukocytes (PMNs). The radioactive product associated with the precipitate was identified as PAF using an ultrahigh-sensitivity TV camera system after extraction and separation by TLC. This TCA method was then used to screen the components of crude preparations that inhibited acetyltransferase activity. Major components from the cortex of Magnoliae (magnolol and honokiol), which have anti-inflammatory and anti-bacterial actions, inhibited the acetyltransferase activity in rat spleen microsomes (IC50, 150 and 150 microM, respectively) and membrane fractions of human PMNs (IC50, 70 and 60 microM, respectively). The inhibitory action of magnolol and honokiol was reversible, and similar to or higher than that of nordihydroguaiaretic acid. PAF production in human PMNs stimulated by the ionophore A23187 was also suppressed dose dependently by magnolol and honokiol. These activities may be relevant to the claimed therapeutic effects of the extract from Magnoliae cortex.

Terpene and lignan glycosides from Pluchea indica

Abstract Investigation of the roots of Pluchea indica afforded a new monoterpene glycoside, plucheoside C, three new eudesmane-type sesquiterpenes, plucheols A, B, plucheoside E and three new lignan glycosides, plucheosides D 1 , D 2 , D 3 together with a known eudesmane-type sesquiterpene. The structures of new compounds were elucidated on the basis of chemical and spectral data.