Dauferulins A-L, daucane-type sesquiterpenes from the roots of Ferula communis: Their structures and biological activities


Meroterpenes and prenylated benzoylphloroglucinol from the flowers of Hypericum formosanum


Acylated iridoid glucoside and xanthones from Canscora lucidissima: Their structures and ferroptosis inhibitory activity

Phytochemical study on the whole plants of a Gentianaceous medicinal plant, Canscora lucidissima, gave one new acylated iridoid glucoside, canscorin A (1), and two new xanthone glycosides (2 and 3) together with 17 known compounds including five xanthones, eight xanthone glycosides, two benzophenone glucosides, caffeic acid, and loganic acid. Canscorin A (1) was assigned as a loganic acid derivative having a hydroxyterephthalic acid moiety by spectroscopic analysis together with chemical evidence, while 2 and 3 were elucidated to be a rutinosylxanthone and a glucosylxanthone, respectively. The absolute configurations of the sugar moieties of 2 and 3 were determined by HPLC analysis. The isolated compounds were evaluated for their inhibitory activities against erastin-induced ferroptosis on human hepatoma Hep3B cells and LPS-stimulated IL-1β production from murine microglial cells.


A suitable stereoisomer of vibrioferrin probes for iron uptake of Vibrio parahaemolyticus


Communiferulins, farnesylated coumarins from the roots of Ferula communis and their anti-neuroinflammatory activity

Three new farnesylated coumarins, communiferulins A-C (1-3), and a farnesylated chromone, ferchromone (4), were isolated from the roots of an Apiaceous plant Ferula communis. Their structures including the relative configurations were elucidated by a combination of spectroscopic analyses and calculations of the NMR data. Communiferulins A-C (1-3) had dihydrofuran rings fused to C-3 and C-4 of their coumarin moieties, while 3 possessed one additional furan ring. HPLC analyses using a chiral column showed 1-4 to be racemates, and the absolute configurations of (+)-1, (-)-1, (+)-2, and (-)-2 were deduced by comparison of their ECD spectra with TDDFT-calculated spectra. Communiferulins A (1) and B (2), and ferchromone (4) showed inhibitory activities on IL-1β production from LPS-stimulated microglial cells.


Tigliane-type diterpene esters from the fruits of Shirakiopsis indica and their anti-HIV activity


Rhodomollosides A and B, glycosides of methyl everninate from the aerial parts of Rhododendron molle

Journal of Asian Natural Products Research


Betuletol, a propolis component, suppresses IL-33 gene expression and effective against eosinophilia

Propolis, a resinous substance produced by honeybees, has been used in folk medicine since ancient times due to its many biological benefits such as antitumor, antioxidant, antimicrobial, anti-inflammatory, and immunomodulatory effects. Propolis contains flavonoids, terpenoids, aromatic aldehydes, and alcohols, which vary with different climate and environmental conditions. In our study, we examined the antiallergic activity of Brazilian green propolis (BGP) and isolated the active compound that can suppress an allergy-sensitive gene, IL-33, expression and eosinophilia. Ethanolic extract of BGP freeze-dried powder was fractionated with several solvent systems, and the active fractions were collected based on activity measurement. The single active compound was found by thin-layer chromatography. Using column chromatography and NMR, the active compound was isolated and identified as 3,5,7-trihydroxy-6,4'-dimethoxyflavone, also known as betuletol. Further, the antiallergic activity of that has been examined in PMA-induced up-regulation of IL-33 gene expression in Swiss 3T3 cells. Our data showed the IL-33 gene suppression both by BGP and the isolated active compound, betuletol. We also found that betuletol suppressed ERK phosphorylation, suggesting it could be effective in suppressing IL-33 mediated eosinophilic chronic inflammation and will provide new insights to develop potent therapeutics against allergic inflammations.


Lanicepines A and B, sesquiterpenes with amino acid-derived substituents from the flowering aerial parts of Saussurea laniceps


Late-stage macrolactonisation enabled by tandem acyl transfers followed by desulphurisation

Intramolecular -acylation of a thiol-installed threonine with a thioester unit, followed by S-O acyl transfer and subsequent desulphurisation, allows the synthesis of lactone peptides. A protocol has been developed enabling the cyclisation of a linear peptide, a reaction which has not been achieved by conventional methods.


Hyperdioxanes, dibenzo-1,4-dioxane derivatives from the roots of Hypericum ascyron

Six dibenzo-1,4-dioxane derivatives (1-6) were isolated from the roots of a Hypericaceous plant Hypericum ascyron. Spectroscopic analyses revealed 2 and 4-6 to be new compounds. The partial racemic natures of 1-3 were concluded by chiral HPLC analyses, while 5 was confirmed to be a racemate. The absolute configurations 1-4 were deduced on the basis of ECD calculations. Biological activity evaluation of the dibenzo-1,4-dioxane derivatives along with two related compounds: hyperdioxanes A (7) and B (8), previously isolated from the same plant material by our group demonstrated that 7 exhibit an anti-HIV activity (IC 5.3 μM, TI 7.2) while 8 showed an inhibitory effect on IL-1β production (inhibition rate: 72.3% at 6.3 μM) from LPS-stimulated microglial cells.


Studies on non-medicinal parts of plant materials: Triterpenes from the roots of Schisandra chinensis


Mechanistic Support for Intramolecular Migrative Cyclization of Propargyl Sulfones Provided by Catalytic Asymmetric Induction with a Chiral Counter Cation Strategy


Diterpenes from an Uzbek medicinal plant Perovskia scrophulariifolia: their structures and anti-neuroinflammatory activity

Phytochemical investigation on the aerial parts of a Lamiaceous medicinal plant Perovskia scrophulariifolia collected in Uzbekistan resulted in the isolation of two new 20-norabietane diterpenes, along with thirteen known diterpenes including one 20-norabietane, eight abietanes, one 6,7-secoabietane, and three icetexanes. The structures of new 20-norabietane diterpenes, perovsfolins C (1) and D (2), were elucidated by spectroscopic analyses aided with calculations of ECD spectra. Perovsfolin C (1) is the first 20-norabietane diterpene possessing a 1,11-epoxy moiety, while perovsfolin D (2) is a 20-norabitetane diterpene with a 2-hydroxy-1,4-quinone moiety as C-ring. Anti-neuroinflammatory activity of the isolated diterpenes on microglial cells was evaluated.


C28 Terpenoids from Lamiaceous plant Perovskia scrophulariifolia: their structures and anti-neuroinflammatory activity

Structurally unique C terpenoids, perovsfolins A () and B (), were isolated from the aerial parts of an Uzbek medicinal plant, (Lamiaceae). Their chemical structures including an unprecedented 6/8/6/6/6 pentacyclic carbon skeleton with a C-C ester moiety were elucidated on the basis of spectroscopic analyses aided by density functional theory calculations as well as chemical evidence. Perovsfolin B () exhibited an anti-neuroinflammatory activity.


Agesasines A and B, Bromopyrrole Alkaloids from Marine Sponges Agelas spp.

Exploration for specialized metabolites of Okinawan marine sponges spp. resulted in the isolation of five new bromopyrrole alkaloids, agesasines A () and B (), 9-hydroxydihydrodispacamide (), 9-hydroxydihydrooroidin (), and 9-keramadine (). Their structures were elucidated on the basis of spectroscopic analyses. Agesasines A () and B () were assigned as rare bromopyrrole alkaloids lacking an aminoimidazole moiety, while - were elucidated to be linear bromopyrrole alkaloids with either aminoimidazolone, aminoimidazole, or -methylated aminoimidazole moieties.


Lophachinins A-E, abietane diterpenes from a Mongolian traditional herbal medicine Lophanthus chinensis

Five new abietane diterpenes, lophachinins A-E (1-5), and eleven known related diterpenes were isolated from a Mongolian traditional herbal medicine, the aerial parts of Lophanthus chinensis (Lamiaceae). The structures of new diterpenes were assigned by spectroscopic analyses. Lophachinins A (1) and B (2) were abietane diterpene possessing an endoperoxy bridge at C-ring. In contrast, lophachinins C-E (3-5) had an abietane skeleton with an aromatized C-ring. The absolute configuration of 1 was elucidated by application of the modified Mosher's method, while those of 2, 3, and 5 were assigned by chemical conversions. The absolute configuration of lophachinin D (4) was deduced by ECD calculation. Anti-inflammatory activity of isolated diterpenes on microglial cells were evaluated.


Sarcaglabrin A, a conjugate of C15 and C10 terpenes from the aerial parts of Sarcandra glabra


Prenylated benzophenone derivatives from Hypericum patulum

A new prenylated benzophenone, hypatulin C (1), was isolated from the leaves of Hypericum patulum together with a biogenetically related analog, hypelodin B (2). Hypatulin C (1) had a tricyclic [4.3.1.0]-decane moiety substituted by four prenyl groups. The structure of 1 was elucidated by detailed spectroscopic analyses, while the absolute stereochemistries of 1 and 2 were assigned by comparison of their ECD spectra with TDDFT calculated spectra.


Linaburiosides A-D, acylated iridoid glucosides from Linaria buriatica


Limonoids from the aerial parts of Munronia pinnata


Hypascyrins A-E, prenylated acylphloroglucinols from Hypericum ascyron

Six new prenylated acylphloroglucinols with menthane moieties, hypascyrins A-E (-) and -hyphenrone J (), together with four known analogues, were isolated from roots. Detailed spectroscopic data analyses resulted in the assignment of their structures. The absolute configuration of was deduced by experimental and calculated ECD data, while those of - were assigned by ECD data analyses as well as chemical conversions. Hypascyrins A (), C (), and E () and -hyphenrone J () exhibited antimicrobial activity against MRSA (MIC values of 4.0, 8.0, 2.0, and 4.0 μM, respectively) and (MIC values of 4.0, 4.0, 2.0, and 4.0 μM, respectively).


Lanostane-type triterpnes from the sclerotium of Inonotus obliquus (Chaga mushrooms) as proproliferative agents on human follicle dermal papilla cells

Chaga mushrooms, the sclerotium of Inonotus obliquus, have been used in Mongolia as a traditional hair shampoo to maintain healthy hair. Bioassay-guided fractionations of the extract of Chaga mushrooms using a proliferation assay on human follicle dermal papilla cells (HFDPCs) gave five lanostane-type triterpenes (1-5), whose structures were identified by spectroscopic evidence. Among these, lanosterol (1), inotodiol (3), lanost-8,24-diene-3β,21-diol (4), and trametenolic acid (5) demonstrated proproliferative effects on HFDPCs more potent than minoxidil, an anti-alopecia agent, used as the positive control. The lanostane-type triterpenes (1, 3, 4, and 5) appeared to be potential candidates of new agents possibly used for hair-care with a stimulative effect on hair growth.


Hyperdioxane A, a conjugate of dibenzo-1,4-dioxane and sesquiterpene from Hypericum ascyron

Two new dibenzo-1,4-dioxane derivatives, hyperdioxanes A (1) and B (2), were isolated from the roots of a Hypericaceous plant, Hypericum ascyron. Hyperdioxane A (1) is a conjugate of dibenzo-1,4-dioxane and sesquiterpene with an unprecedented heptacyclic ring system. The structures of 1 and 2 were assigned by detailed spectroscopic analyses, including application of a modified Mosher's method. A possible biogenetic pathway of hyperdioxane A (1) from hyperdioxane B (2) and a sesquiterpene, eremophil-9,11(13)-dien-8β,12-olide (3), is presented.


Rigenolides D-H, norsecoiridoid and secoiridoids from Gentiana rigescens Franch

Five new compounds, rigenolides D-H (1-5), were isolated from the aerial parts of Gentiana rigescens Franch. Their structures were assigned by detailed spectroscopic analyses and chemical conversions. Rigenolides D (1) and E (2) were elucidated to be a secoiridoid and a norsecoiridoid, respectively, possessing a dienone moiety in common. Rigenolides F-H (3-5) were assigned as acylated secoiridoid glucosides.


Agelamasines A and B, diterpene alkaloids from an Okinawan marine sponge Agelas sp.


Phloroglucinol derivatives and a chromone gluycoside from the leaves of Myrtus communis


Methanol extraction fraction from Citrus Sudachi peel exerts lipid reducing effects in cultured cells.

Ectopic fat accumulation is associated with insulin resistance and type 2 diabetes mellitus. Citrus sudachi is an evergreen tree that is found mainly in Tokushima Prefecture in Japan. Previously, it was demonstrated that Citrus sudachi could inhibit the rising trend of blood glucose and fatty acid in human subjects. In the current study, we illustrated the function of methanol extracts from sudachi peel and investigated the mechanism of this effect. We got the five kinds of methanol extracts by using diaion HP-20, and those were named by hydrophobicity from M-F1 to M-F5. Among the 5 kinds of sudachi methanol extracts, only M-F4 significantly decreased the intracellular triglyceride of C2C12 cells. It augmented the AMPK activity and increased the transcription of PPARα and its downstream targets CPT-1b and UCP2. In conclusion, M-F4 improved the lipid metabolism possibly through AMPK, PPARα and their downstream targets like CPT-1b and UCP2. Furthermore, this extract may be useful for preventing obesity and diabetes related diseases. J. Med. Invest. 65:225-230, August, 2018.

The Journal of Medical Investigation : JMI


Guianolactones A and B, two rearranged pentacyclic limonoids from the seeds of Carapa guianensis


Stereochemical assignments of rubiaquinones A-C, naphthoquinone derivatives from Rubia yunnanensis


Rigenolides B and C, conjugates of norsecoiridoid and secoiridoid glucoside from Gentiana rigescens Franch.


Frondhyperins A-D, short ketide-phenylketide conjugates from Hypericum frondosum cv. Sunburst


Hitorins A and B, hexacyclic C25 terpenoids from Chloranthus japonicus

Two novel C25 terpenoids with a 6/5/5/5/5/3 hexacyclic skeleton including one γ-lactone ring and two tetrahydrofuran rings, hitorins A (1) and B (2), were isolated from the aerial parts of Chloranthus japonicus. The structures of 1 and 2 were elucidated on the basis of spectroscopic analyses as well as TDDFT ECD calculations. Hitorins A (1) and B (2) might be biogenetically derived from eudesmane sesquiterpene and thujane monoterpene.


Hypatulins A and B, meroterpenes from Hypericum patulum

Two novel prenylated benzophenone related meroterpenes, hypatulins A (1) and B (2), were isolated from the leaves of Hypericum patulum. The structures of 1 and 2 were assigned by spectroscopic analysis, chemical conversion, and calculations of the ECD (electron circular dichroism) spectra. Hypatulin A (1) had a unique densely substituted tricyclic octahydro-1,5-methanopentalene core, while hypatulin B (2) possessed a bicyclo[3.2.1]octane moiety. Hypatulin A (1) exhibited antimicrobacterial activity against Bacillus subtilis. A possible biogenetic pathway of the new meroterpenes 1 and 2 from a prenylated benzophenone was presented.


Erecricins A-E, prenylated acylphloroglucinols from the roots of Hypericum erectum

Six new prenylated acylphloroglucinols, erecricins A-E (1-5) and adotogirin (6), were isolated from the roots of Hypericum erectum (Hypericaceae). Their structures were assigned on the basis of spectroscopic evidences. Erecricins A-E (1-5) are bicyclic prenylated acylphloroglucinols possessing a chromane or a chromene skeleton. Adotogirin (6) is a simple achylphloroglucinol with an O-geranyl moiety. Antimicrobial activities of these acylphloroglucinols were also evaluated.


Acylated triterpene saponins from the stem bark of Acer nikoense

Three new acylated triterpene saponins, acernikoenosides A-C (1-3), were isolated from the stem bark of Acer nikoense, together with a known sterol glucoside. Their structures were elucidated on the basis of extensive spectroscopic analyses. This study provided the first example of triterpene saponins isolated from this plant. The anti-genotoxic activity of 1, 3 and 4 against ultraviolet irradiation was evaluated by comet assay.


Yezo'otogirins A-H, acylphloroglucinols and meroterpenes from Hypericum yezoense

Investigation of the methanolic extract from the aerial parts of Hypericum yezoense resulted in the isolation of three new acylphloroglucinols, yezo'otogirins D-F (1-3), and two new meroterpenes, yezo'otogirins G (4) and H (5). The structures of 1-5 were assigned on the basis of spectroscopic data. Yezo'otogirin D (1) is an acylphloroglucinol with a monoterpene moiety linked through an ether bond, while yezo'otogirins E (2) and F (3) are polyprenylated acylphloroglucinols possessing a tricyclic core. Yezo'otogirins G (4) and H (5) are linear meroterpenes with an enolized -diketone moiety. Yezo'otogirin E (2) exhibited antimicrobial activity against Escherichia coli and Staphylococcus aureus.


Merohyperins A-C, meroterpenes from the leaves of Hypericum chinense


Tetrahydroxanthones from Mongolian medicinal plant Gentianella amarella ssp. acuta


Agelamadin F and tauroacidin E, bromopyrrole alkaloids from an Okinawan marine sponge Agelas sp.


Miltiorins A-D, diterpenes from Radix Salviae miltiorrhizae

Constituents of the anti-influenza A neuraminidase (NA) active extract from Radix Salviae miltiorrhizae were investigated, resulting in the isolation of four new diterpenes, miltiorins A-D (1-4), together with eight known diterpenes. The structures of 1-4 were assigned by spectroscopic analysis. Miltiorins A-C (1-3) were abietane diterpenes possessing a 2-acetoxy group and a 12-hydroxy group in common, while miltiorin D (4) was a 11,12-seco-abietane diterpene with a -lactone ring. Miltiorin D (4) is the first example of a 11,12-seco-abietane diterpene from natural sources. Anti-NA activities of the isolated diterpenes were evaluated.


Three new oxylipins from an Okinawan marine sponge Plakortis sp.


Prenylated benzophenones from Triadenum japonicum

Six new prenylated benzophenones, (-)-nemorosonol (1) and trijapins A-E (2-6), were isolated from the aerial parts of Triadenum japonicum. (-)-Nemorosonol (1) and trijapins A-C (2-4) have a common tricyclo[4.3.1.0(3,7)]decane skeleton, while 1 is an enantiomer of (+)-nemorosonol previously isolated from Clusia nemorosa. The absolute configuration of (-)-nemorosonol (1) was assigned by ECD spectroscopy. Trijapins A-C (2-4) are analogues of 1 possessing an additional tetrahydrofuran ring. Trijapins D (5) and E (6) are prenylated benzophenones with a 1,2-dioxane moiety and a hydroperoxy group, respectively. (-)-Nemorosonol (1) exhibited antimicrobial activity against Escherichia coli (MIC, 8 g/mL), Staphylococcus aureus (MIC, 16 g/mL), Bacillus subtilis (MIC, 16 g/mL), Micrococcus luteus (MIC, 32 g/mL), Aspergillus niger (IC50, 16 g/mL), Trichophyton mentagrophytes (IC50, 8 g/mL), and Candida albicans (IC50, 32 g/mL), while trijapin D (5) showed antimicrobial activity against C. albicans (IC50, 8 g/mL).


Algiolide A, secoiridoid glucoside from Mongolian medicinal plant Gentiana algida

A new secoiridoid glucoside, algiolide A (1), was isolated from the aerial parts of a Mongolian traditional herbal medicine Gentiana algida (Gentianaceae). The structure of 1 was elucidated on the basis of spec- troscopic analysis and chemical conversion as well as calculations of NMR and ECD spectra. Algiolide A (1) has a novel skeleton consisting of fused a,b-unsaturated-d-lactone and cyclopentene rings.


Halichonadins M-Q, sesquiterpenes from an Okinawan marine sponge Halichondria sp.


2-Debromoagelamide U, 2-debromomukanadin G, and 2-debromoagelamide P from marine sponge Agelas sp.


Agelamadins C-E, Bromopyrrole Alkaloids Comprising Oroidin and 3-Hydroxykynurenine from a Marine Sponge Agelas sp.

Three structurally unique bromopyrrole alkaloids, agelamadins C-E (1-3), were isolated from a marine sponge Agelas sp. Agelamadin C (1) possesses a hybrid structure of oroidin and 3-hydroxykynurenine connected through a dihydro-1,4-oxazine moiety. Agelamadins D (2) and E (3) are a C-9/C-10 diastereomer and a 10-epimer of 1, respectively. The structures of 1-3 were elucidated on the basis of spectroscopic analysis as well as application of a PGME method and a TDDFT ECD calculation. Antimicrobial activity of 1-3 was evaluated.


Hypelodins A and B, polyprenylated benzophenones from Hypericum elodeoides.

Two new polyprenylated benzophenones, hypelodins A (1) and B (2), were isolated from the aerial parts of the Chinese medicinal plant Hyperium elodeoides (Choisy). Their structures were elucidated on the basis of spectroscopic evidence. Hypelodin A (1) is a polyprenylated benzophenone having a tetrahydropyrane ring with three prenyl groups and one 4-methyl-1,3-pentadiene moiety, while hypelodin B (2) has a cage-like structure with a 6/6/5/7/6/5 hexacyclic ring system.


Agelamadins A and B, Dimeric Bromopyrrole Alkaloids from a Marine Sponge Agelas sp.

Two structurally unique dimeric bromopyrrole alkaloids, agelamadins A (1) and B (2), were isolated from a marine sponge Agelas sp. Agelamadins A (1) and B (2) have a structure consisting of an agelastatin-like tetracyclic moiety and an oroidin-like linear moiety in common. The structures of 1 and 2 were elucidated on the basis of spectroscopic analysis. The antimicrobial activity and cytotoxicity of agelamadins A (1) and B (2) were evaluated.


Hikiokoshins A-I, diterpenes from the leaves of Isodon japonicus.

Diterpenes, hikiokoshins A-I, and twelve known diterpenes were isolated from the leaves of Isodon japonicus (Burm. f.) H. Hara (Lamiaceae). The hikiokoshins A-I possess various skeletons such as ternifonane {hikiokoshin A}, ent-6,7:8,15-diseco-6,8-cyclokauran-7,20-olide {hikiokoshin B}, ent-6,7-secokauran-7,20-olide {hikiokoshin C}, and ent-7,20-epoxykaurane {hikiokoshins D-I}. Their structures were elucidated on the basis of spectroscopic analysis. Antimicrobial activities of hikiokoshins A and B were evaluated.


Hyrtimomines, indole alkaloids from Okinawan marine sponges Hyrtios spp.


Bromopyrrole alkaloids from a marine sponge Agelas sp.

Five new bromopyrrole alkaloids, 2-bromokeramadine (1), 2-bromo-9,10-dihydrokeramadine (2), tauroacidins C (3) and D (4), and mukanadin G (5), were isolated from an Okinawan marine sponge Agelas sp. The structures of 1-5 were elucidated on the basis of spectroscopic data and conformational analysis. Mukanadin G (5) has a tricyclic skeleton consisting of a fused tetrahydrobenzaminoimidazole and 2,5-dioxopyrrolidine moieties. Antimicrobial activities of 1-3, and 5 as well as three related known bromopyrrole alkaloids, keramadine (6), tauroacidin A (7), and taurodispacamide A (8) were evaluated.


Nagelamides X-Z, dimeric bromopyrrole alkaloids from a marine sponge Agelas sp.

Three new dimeric bromopyrrole alkaloids, nagelamides X-Z (1-3), were isolated from a marine sponge Agelas sp. Nagelamides X (1) and Y (2) possess a novel tricyclic skeleton consisting of spiro-bonded tetrahydrobenzaminoimidazole and aminoimidazolidine moieties. Nagelamide Z (3) is the first dimeric bromopyrrole alkaloid involving the C-8 position in dimerization. The structures of 1-3 were elucidated on the basis of spectroscopic data. Nagelamides X-Z (1-3) exhibited antimicrobial activity.


Manzamenone O, new trimeric fatty acid derivative from a marine sponge Plakortis sp.

A new structurally unique trimeric fatty acid derivative, manzamenone O (1), was isolated from a marine sponge Plakortis sp. Manzamenone O (1) has a novel skeleton consisting of C-C bonded octahydroindenone and dioxabicyclo[3.3.0]octane moieties and three long aliphatic chains. The structure of 1 was elucidated on the basis of spectroscopic data and conformational analysis. Manzamenone O (1) exhibited antimicrobial activity against Micrococcus luteus, Aspergillis niger, and Trichophyton mentagrophytes.


Hyrtimomines A-C, new heteroaromatic alkaloids from a sponge Hyrtios sp.

Three new alkaloids, hyrtimomines A-C (1-3), were isolated from an Okinawan marine sponge Hyrtios sp. The structures of 1-3 were elucidated on the basis of spectroscopic analysis and application of a phenylglycine methyl ester (PGME) method. Hyrtimomines A (1) and B (2) are heteroaromatic alkaloids possessing a fused hexacyclic 6/5/6/6/7/5 ring system, while hyrtimomine C (3) is an alkaloid consisting of hydroxyindole and azepino-hydroxyindole moieties. Hyrtimomine A (1) exhibited cytotoxicity against KB and L1210 cells.


Nagelamides U-W, bromopyrrole alkaloids from a marine sponge Agelas sp.


Hyrtimomines D and E, bisindole alkaloids from a marine sponge Hyrtios sp.


Halichonadins K and L, new dimeric sesquiterpenoids from a sponge Halichondria sp.

Two new structurally unique dimeric sesquiterpenoids, halichonadins K (1) and L (2), were isolated from an Okinawan marine sponge Halichondria sp. The structures of 1 and 2 were elucidated on the basis of spectroscopic analysis including a single crystal X-ray diffraction analysis and chemical conversion. Halichonadins K (1) and L (2) are homodimers of the eudesmane sesquiterpene linked with a piperidine ring through amide bonds. Halichonadin K (1) showed moderate cytotoxicity against KB cells.


Biyoulactones D and E, meroterpenoids from Hypericum chinense


Heteroaromatic alkaloids, nakijinamines, from a sponge Suberites sp.


Prenylated acylphloroglucinols, chipericumins A-D, from Hypericum chinense.

Two new tetracyclic prenylated acylphloroglucinols, chipericumins A (1) and B (2), were isolated from the roots of Hypericum chinense, together with two new tricyclic prenylated acylphloroglucinols, chipericumins C (3) and D (4). Their structures were elucidated by spectroscopic data. Chipericumins A-D (1-4) are prenylated acylphloroglucinols having a spiro skeleton with an acyl group, a methyl group, a C(5) unit, and a monoterpene moiety in common.


Biyoulactones A-C, new pentacyclic meroterpenoids from Hypericum chinense.

Three novel pentacyclic meroterpenoids with a unique dilactone structure containing C-C bonded bi- and tricyclic -lactone moieties, biyoulactones A-C (1-3), were isolated from the roots of Hypericum chinense, and their structures were elucidated on the basis of spectroscopic data. The relative and absolute stereochemistry of 1 was assigned by a combination of NOESY and a single crystal X-ray diffraction analysis.


Yojironins E-I, prenylated acylphloroglucinols from Hypericum yojiroanum.

Five new prenylated acylphloroglucinols, yojironins E- (1-5), were isolated from the whole plants of Hypericum yojiroanum. Their structures were elucidated by spectroscopic data. Yojironin E (1) exhibited antimicrobial activity against Aspergillus niger, Candida albicans, Cryptococcus neoformans, and Trichophyton mentagrophytes.

Bioorganic & Medicinal Chemistry Letters


Halichonadins G-J, new sesquiterpenoids from a sponge Halichondria sp.


Yojironins A-D, meroterpenoids and prenylated acylphloroglucinols from Hypericum yojiroanum


Stelliferins J-N, isomalabaricane-type triterpenoids from Okinawan marine sponge Rhabdastrella cf. globostellata


Veramadines A and B, New Steroidal Alkaloids from Veratrum maackii var. japonicum.

Two new steroidal alkaloids possessing a cevanine-type skeleton, veramadines A (1) and B (2), were isolated from the aerial parts of Veratrum maackii var. japonicum. The structures of 1 and 2 were elucidated on the basis of their spectroscopic data.


Petiolins J-M, prenylated acylphloroglucinols from Hypericum pseudopetiolatum var. kiusianum.

Four new prenylated acylphloroglucinols, petiolins J-M (1-4), were isolated from aerial parts of Hypericum pseudopetiolatum var. kiusianum, and the structures were elucidated by spectroscopic data and a single-crystal X-ray diffraction analysis. Petiolin J (1) exhibited antimicrobial activity.


Biyouxanthones A-D, prenylated xanthones from roots of Hypericum chinense


Petiolins F-I, benzophenone rhamnosides from Hypericum pseudopetiolatum var. kiusianum.

Four new benzophenone-O-rhamnosides, petiolins F-I (1-4), were isolated from aerial parts of Hypericum pseudopetiolatum var. kiusianum, and the structures were elucidated by spectroscopic data and chemical means.


Xanthones from Hypericum chinense and their cytotoxicity evaluation.

A xanthonolignoid, 2-O-demethylkielcorin, and a phenylxanthone, chinexanthone A, were isolated from stems of Hypericum chinense together with four known xanthonolignoids and seven known xanthones. Their structures were established by spectroscopic analysis, as their optical properties and absolute stereochemistry determined. The cytotoxicities of the isolated xanthone derivatives as well as additional 32 xanthones against a panel of human cancer cell lines were also evaluated.


Acylphloroglucinol, biyouyanagiol, biyouyanagin B, and related spiro-lactones from Hypericum chinense.

Biyouyanagiol (1), an acylphloroglucinol-related compound having a unique cyclopenta-1,3-dione moiety, was isolated from a Japanese traditional medicinal plant, Hypericum chinense, together with three new spiro-lactone-related derivatives, biyouyanagin B (2), 5,6-dihydrohyperolactone D (3), and 4-hydroxyhyperolactone D (4). Their structures were established on the basis of spectroscopic evidence. In a cytotoxicity assay against human cancer cell lines including multidrug-resistant (MDR) cancer cell lines, several compounds demonstrated enhanced cytotoxicity against MDR KB cells in the presence of colchicine.


Petiolins D and E, phloroglucinol derivatives from Hypericum pseudopetiolatum var. kiusianum.


Chromone and chromanone glucosides from Hypericum sikokumontanum and their anti-Helicobacter pylori activities.

Chromone glucosides, takanechromones A-C (1, 2 and 5) and chromanone glucosides, named takanechromanones A and B (3 and 4), were isolated from the methanolic extracts of Hypericumsikokumontanum together with 27 known compounds. Their structures were established based on spectroscopic evidence. The isolated compounds and some chromone derivatives were assayed for antimicrobial activity against Helicobacter pylori and cytotoxicity against human cancer cell lines.


Yezo'otogirins A-C, tricyclic terpenoids from Hypericum yezoense


Tomoenones A-H, cytotoxic phloroglucinol derivatives from Hypericum ascyron

Phloroglucinol derivatives tomoeones A-H (1-8) and three known compounds were isolated from leaves of Hypericum ascyron. Their structures were established based on spectroscopic analyses. They are all acylphloroglucinol derivatives possessing a spiro skeleton with geminal isoprenyl groups and a monoterpene moiety, and they are stereoisomers to each other at C-4 and C-13. They appear to be a class of phloroglucinol derivatives. Cytotoxicities of the isolated phloroglucinol derivatives against human tumor cell lines, including multidrug-resistant (MDR) cancer cell lines, were evaluated. Tomoeone F (6) demonstrated significant cytotoxicity against KB cells with an IC50 value of 6.2 microM. Compound 6 was also cytotoxic against MDR cancer cell lines (KB-C2 and K562/Adr), which was more potent than doxorubicin.


Prenylated Phrologrucinol Derivatives from Hypericum perforatum var. angustifolium

Two new prenylated phloroglucinol derivatives and 15 known compounds were isolated from the aerial parts of Hypericum perforatum var. angustifolium. Their structures were determined on the basis of spectroscopic evidence.


Petiolins A-C, phloroglucinol derivatives from Hypericum pseudopetiolatum var. kiusianum

Two new phloroglucinol derivatives possessing chromane skeleton, petiolins A (1) and B (2), and a new phloroglucinol derivative containing a dihydrofuran ring, petiolin C (3), were isolated from aerial parts of Hypericum pseudopetiolatum var. kiusianum. The gross structures of 1-3 were elucidated by spectroscopic data, and the relative stereochemistry of 3 was elucidated by NOESY data. Petiolins A-C (1-3) showed modest cytotoxicity, while petiolin C (3) exhibited antifungal activity.


Takaneones A-C, prenylated butylphloroglucinol derivatives from Hypercum shikokumontanum


Prenylated xanthones from Hypericum ascyron


Xanthones from Stems of Hypericum chinense

Six new xanthones, 4,6-dihydroxy-2,3-dimethoxyxanthone (1), 2,6-dihydroxy-3,4-dimethoxyxanthone (2), 6-hydroxy-2,3,4-trimethoxyxanthone (3), 3,6-dihydroxy-1,2-dimethoxyxanthone (4), 4,7-dihydroxy-2,3-dimethoxyxanthone (5), and 3,7-dihydroxy-2,4-dimethoxyxanthone (6) were isolated from the stems of Hypericum chinense, together with four known xanthones. Their structures were established based on spectroscopic studies.


Six xanthones, 1,3,7-trihydroxy-2-(2-hydroxy-3-methyl-3-butenyl)-xanthone (1), 1,7-dihydroxy-2,3-[2''-(1-hydroxy-1-methylethyl)-dihydrofurano]-xanthone (2), 1,3,7-trihydroxy-5-methoxyxanthone (3), 1,7-dihydroxy-5,6-dimethoxyxanthone (4), 4,5-dihydroxy-2,3-dimethoxyxanthone (5), 1,3-dihydroxy-2,4-dimethoxyxanthone (6) and 21 known xanthones were isolated from the leaves and stems of Hypericum chinense. Their structures were established based on spectroscopic studies.


Chemical Constituents from the Peels of Citrus sudachi

A methanol extract of the peels of Citrus sudachi gave five new compounds (1-5) and 27 known compounds. The structures were elucidated on the basis of spectroscopic evidence. Several of these compounds were assayed for antimicrobial activity against methicillin-resistant Staphylococcus aureus and Helicobacter pylori, and sudachitin (6) and 3'-demethoxysudachitin (7) were the most active.


Biyouyanagin A, an Anti-HIV Agent from Hypericum chinense L. var. salicifolium

[structure: see text] A structurally unique hydrophobic compound, biyouyanagin A, was isolated from the MeOH extract of the leaves of Hypericum chinense L. var. salicifolium. The structure of biyouyanagin A was elucidated on the basis of spectroscopic evidence. Biyouyanagin A showed a significant activity against HIV and inhibited cytokine production.


Novel antioxidants isolated from plants of the genera Ferula, Inula, Prangos and Rheum collected in Uzbekistan

We examined the effects of 48 compounds isolated from Ferula pallida, F. penninervis, Inula macrophylla, Prangos pabularia, P. tschimganica and Rheum maximowiczii collected in Uzbekistan on ADP/Fe2+-induced lipid peroxidation of egg yolk phosphatidylcholine liposomes. Of those compounds, 23 inhibited ADP/Fe2+-induced lipid peroxidation and nine showed especially strong inhibition of lipid peroxidation. Most compounds that inhibited peroxidation scavenged the 1,1'-diphenyl-2-picrylhydrazyl (DPPH) radical, indicating that the inhibition was due to radical scavenging. However, some compounds did not scavenge DPPH but inhibited lipid peroxidation significantly, suggesting that their inhibitory effect was not due to radical scavenging but to some other mechanism, such as prevention of Fe2+ function. Thus, we found various new antioxidants, some of which had a unique mechanism of action, in Ferula, Inula, Prangos and Rheum plants collected in Uzbekistan as seeds used in medicine.


Prenylated Benzophenones and Xanthones from Hypericum scabrum

Two new polyprenylated benzophenones, a new polyprenylated phloroglucinol, and six new xanthone derivatives were isolated from the aerial parts of the Uzbekistan medicinal plant Hypericum scabrum. Their structures were elucidated on the basis of spectroscopic evidence. The isolated compounds showed moderate cytotoxicity for human tumor cells.


Kaurane and abietane diterpenoids from Tripterygium doianum (Celastraceae)

Extraction of Tripterygium doianum (Celastraceae) afforded five new diterpenoids and 11 known diterpenoids belonging to the ent-kaurane and abietane families. Their structures were established based on spectroscopic studies. The isolated compounds showed moderate cytotoxicity against human tumor cell assays.


Terpenoids from Tripterygium doianum (Celastraceae)

The extract of Tripterygium doianum (Celastraceae) afforded three triterpenoids [3beta-acetoxy-11-ursen-13alpha,30-olide, 25-chloro-24-hydroxytirucall-7-en-3-one and tirucall-7-en-3,24-dione], two sesquiterpenoids [5alpha-acetoxy-1beta,8alpha-bis-cinnamoyl-4alpha-hydroxydihydroagarofuran and 5alpha-acetoxy-1beta-benzoyl-8alpha-cinnamoyl-4alpha-hydroxydihydroagarofuran] and nine known triterpenoids. Their structures were established based on spectroscopic studies.


特異な化学構造をもつ植物由来の生物活性物質の探索-オトギリソウ属植物の成分について-


三好市東祖谷地区の民間薬調査

三好市東祖谷地区の民間薬調査