Chemical constituents from the petioles and leaves of Aquilaria sinensis

Nineteen reported compounds (1–19) were obtained from the dried petioles and leaves of Aquilaria sinensis (Thymelaeacea) by phytochemical methods. Their structures were determined on the basis of spectroscopic methods. Among them, compounds 6–14 and 16 were firstly obtained from the genus Aquilaria, 2 and 3 were obtained from A. sinensis for the first time. In addition, the chemotaxonomic relationships between A. sinensis and some other plants were also discussed.     

Microbial metabolism of cannflavin A and B isolated from Cannabis sativa

Microbial metabolism of cannflavin A (1) and B (2), two biologically active flavonoids isolated from Cannabis sativa L., produced five metabolites (3–7). Incubation of 1 and 2 with Mucor ramannianus (ATCC 9628) and Beauveria bassiana (ATCC 13144), respectively, yielded 6″S,7″-dihydroxycannflavin A (3), 6″S,7″-dihydroxycannflavin A 7-sulfate (4) and 6″S,7″-dihydroxycannflavin A 4′-O-α-l-rhamnopyranoside (5), and cannflavin B 7-O-β-d-4?-O-methylglucopyranoside (6) and cannflavin B 7-sulfate (7), respectively. All compounds were evaluated for antimicrobial and antiprotozoal activity.     

Anthocyanins and flavonols from the flowers of Amherstia nobilis endemic to Myanmar

Three anthocyanins (1–3) and eight flavonols (4–11) were isolated from the flowers of Amherstia nobilis endemic to Myanmar. Anthocyanins were identified as cyanidin 3-O-glucoside (1), 3-O-xyloside (2), and peonidin 3-O-glucoside (3). On the other hand, flavonols were identified as isorhamnetin 3-O-glucoside (4), 7-O-glucoside (5), 3,7-di-O-glucoside (6) and 3-O-rutinoside (7), quercetin 3-O-rutinoside (8) and 3-O-glucoside (9), and kaempferol 3-O-rutinoside (10) and 3-O-glucoside (11). Although an anthocyanin, pelargonidin 3-O-pentoside, has been reported from the flowers of A. nobilis, it was not found in this survey. The presence of flavonols in A. nobilis was reported in this survey for the first time. Flavonoid composition of Amherstia was chemotaxonomically compared with those of phylogenetically related genera Cynometra and Brownea.     

Styrylpyrones from the medicinal fungus Phellinus baumii and their antioxidant properties

During the search for natural antioxidants from basidiomycetes, a new styrylpyrone, baumin (1), was isolated from the cultivated medicinal fungus Phellinus baumii, together with known compounds, davallialactone (2), hispidin (3), hypholomine B (4), interfungin A (5), inoscavin A (6), and phelligridin D (7), which were previously isolated from the medicinal fungi Phellinus ignarius, Phellinus linteus, and Inonotus xeranticus. Their structures were elucidated by extensive spectroscopic methods. These compounds exhibited antioxidant activity through Fenton reaction inhibition via iron chelation and free radical scavenging.     

A pair of new tetrahydro-naphthalenone enantiomers from Eremurus altaicus (Pall.) Stev.

A new racemic mixture of a 4-hydroxytetralone derivative, altaicusin A (1), was isolated from the whole plant of Eremurus altaicus (Pall.) Stev., together with three anthraquinones (compounds 2–4) and two naphthalene derivatives (5–6). The racemic altaicusin A (1) was further purified by chiral HPLC to yield a pair of enantiomers, (+)-(4S)-altaicusin A (1a) and (−)-(4R)-altaicusin A (1b). Their structures were established on the basis of spectroscopic analysis, including IR, HR-TOF-MS, and NMR. The absolute configurations of compounds 1a and 1b were elucidated by quantum chemical ECD calculations. Compounds 3 and 6 exhibited inhibitory activity against protein tyrosine phosphatase 1B (PTP1B).     

Chemical constituents from the roots of Asarum sieboldii Miq. var. Seoulense Nakai

Fourteen compounds were isolated from the 95% ethanol reflux extract of Asarum sieboldii Miq. var. Seoulense Nakai, including five phenanthrene derivatives (1–5), three isobutyl amides (6–8), three phenylpropanoids (9–11) and three lignins (12–14). The structures of these compounds were identified by spectroscopic methods and by comparison with the reported spectroscopic data. Among them, compounds 6 and 11 were firstly reported from the family Aristolochiaceae, and compounds 3 and 4 were reported for the first time from the genus Asarum. Additionally, compounds 1, 2 and 8 were isolated from A. sieboldii Miq. var. Seoulense Nakai for the first time. These compounds have shown chemical relationships between A. sieboldii Miq. var. Seoulense Nakai and other species of Asarum as well as those found in the genus Aristolochia in the family Aristolochiaceae.     

Diarylpentanoids from Diplomorpha canescens and Diplomorpha ganpi

Two new α-hydroxy ketone type diarylpentanoids, diplomorphanone A, 2(S)-hydroxy-1-(4-hydroxyphenyl)-5-phenyl-1-pentanone (1) and diplomorphanone B, 2(R)-hydroxy-1,5-diphenyl-1-pentanone (2) were isolated from aerial parts of Diplomorpha canescens (Meisn.) C.A. Meyer and roots of Diplomorpha ganpi (Sieb. et Zucc.) Nakai, respectively. Nine known compounds including diarylpentanoids (3–6), phenylpropanoid derivatives (7–9), (+)-afzelechin (10) and apiosylskimmin (11) were also isolated for the first time from D. ganpi. Structures of these compounds were elucidated on the basis of spectroscopic data.     

Phenolic compounds and ecdysteroids of Diplazium esculentum (Retz.) Sw. (Athyriaceae) from Japan and their chemotaxonomic significance

Four phenolic compounds, (2R)-3-(4′-hydroxyphenyl) lactic acid, trans-cinnamic acid (2), protocatechuic acid (3) and rutin (4), and three ecdysteroids, amarasterone A1 (5), makisterone C (6) and ponastrone A (7) were isolated and identified from the young fronds of Diplazium esculentum (Retz.) Sw. (Athyriaceae). The structures of these compounds were elucidated on the basis of NMR spectral data and comparison with literature values. Compounds 1, 2 and 5–7 were isolated for the first time from title plant. Their structure elucidation and chemotaxonomic significance are explained in detail.     

Monoterpenoid indole alkaloids from Palicourea crocea

A new monoterpenoid indole alkaloid N-oxide, 3,4-dihydro-1-(1-β-d-glucopyranosyloxy-1,4a,5,7a-tetrahydro-4-methoxycarbonylcyclopenta[c]pyran-7-yl)-β-carboline-N²-oxide (3) and two known monoterpenoid indole alkaloids, croceaine A (1) and psychollatine (2), were isolated from Palicourea crocea (Rubiaceae) from Trinidad. The structures of 1–3 were determined on the basis of spectral and other physical data. Compounds 1 and 2 were previously isolated from plants of different genera viz. Palicourea crocea and Psychotria umbellata, respectively, both collected in Brazil. The results support the proposal that the genus Palicourea and the subgenus Heteropsychotria should be combined into a single genus.     

Cytotoxic abietane-type diterpenoids from twigs and leaves of Croton laevigatus

Seven new abietane-type diterpenoids, crotolaevigatones A–G (1–7), one new aromatic compound, hexyl Z-ferulate (8), along with three known diterpenoids (9–11) and one known aromatic ester, hexyl E-ferulate (12), were obtained from the twigs and leaves of Croton laevigatus. The structures of all isolated compounds were established on the basis of extensive NMR and MS spectroscopic analyses. Compounds 2 and 7 exhibited weak anti-proliferative activity against the A549 and MDA-MB-231 cancer cells, while compound 10 selectively showed significant inhibitory activity against the A549 cancer cells.     

Chemical constituents from bulbs of Fritillaria pallidiflora Schrenk

A new steroidal alkaloid, 5α, 14α, 17β-cevanin-6-oxo-3β, 20β, 24β-triol(1), together with ten known compounds (2–11) were isolated from the bulbs of Fritillaria pallidiflora Schrenk. Their structures were determined on the basis of spectroscopic analysis and by comparison of their spectral data with those reported in the literature. Compounds 8, 9, 10 were obtained from the genus Fritillaria for the first time; Compounds 2, 3, 4 and 11 are isolated from this plant for the first time.     

Phenol derivatives from the cold-seep fungus Aspergillus sydowii 10–31

Two bisabolane-type sesquiterpenoid phenols inclusive of the known (7 S)-flavilane A (1) and the new (7 S)− 4-iodo-flavilane A (2), along with a new tetraphenyl ether, bisviolaceol II (3), were isolated from the cold-seep fungus Aspergillus sydowii 10–31. Their structures were identified through spectroscopic methods, such as MS, IR, and NMR, and the absolute configurations of 1 and 2 were ascertained by comparison of ECD curves. Compounds 1 and 2 represent rarely encountered sulfur-bearing sesquiterpenes in nature, and the iodination in 2 makes it unique in particular. Additionally, 3 is the first tetraphenyl ether derivative from the fungal species A. sydowii. Compounds 1-3 inhibited the growth of several Vibrio bacteria and harmful microalgae.     

A new meroterpenoid from endophytic fungus Talaromyces amestolkiae CS-O-1

Talaromyces amestolkiae CS-O-1, isolated from Tripterygium Wilfordii Hook. f., was identified based on its ITS and 18S rDNA gene sequencing. A new meroterpenoid, chrodrimanin T (1), along with six known compounds, nicotinamide (2), penipyridone D (3), penipyridone A (4), 3-benzylidene-8,8a-dihydroxy-2-methyl-hexahydro-pyrrolo[1,2-a]pyrazine-1,4-dione (5), butyl-isobutyl-phthalate (6), and aspergillumarin A (7), were isolated from Talaromyces amestolkiae CS-O-1. The structures and relative configurations of these compounds were established by the analysis of HRMS, 1D and 2D-NMR spectroscopy and the comparison with data in the literature. The compounds 2–6 were first isolated from Talaromyces genus. Herein, the chemotaxonomic significance of these compounds is described.     

Phenolic compounds from the roots of Ochna schweinfurthiana and their antioxidant and antiplasmodial activities

An investigation of compounds extracted from Ochna schweinfurthiana roots with ethyl acetate led to the isolation of three new compounds 4⿴-methoxylophirone A (1), 4,4⿲,4⿴⿿trimethoxylophirone A (2) and (4E;7Z)-3,8-dicarboxy-1-(O-β-d-glucopyranosyl-(1 ⿿ 6)-O-β-d-glucopyranosyl-2,9-dihydroxyhexeicosa-4,7-diene (3). Six known compounds were also identified, including Calodenone (4), Calodenine B (5), Lophirone A (6), Gerontoisoflavone A(7), 16α,17-dihydroxy-ent-kauran-19-oic acid (8) and 3β-O-d-glucopyranosyl-β-sitosterol (9). This report describes the first time that compounds 4-8 have been isolated from this plant, while 8 has never been identified in the genus Ochna. Some of the isolated compounds were evaluated for their antiplasmodial activity against the chloroquine-sensitive Plasmodium falciparum strain 3D7 and antioxidant activity using DPPH radical scavenging and Ferric reducing-antioxidant power (FRAP) assays. Compound 5 exhibited prominent radical scavenging and FRAP activities, while 7 had weak activity. Compound 1 showed good in vitro anti-plasmodial activity. The structures of the isolated compounds were elucidated by spectroscopic methods and comparisons with prior data in the literature.     

Indoloditerpenes from an algicolous isolate of Aspergillus oryzae

Two new indoloditerpene derivatives asporyzin A (1) and asporyzin B (2), one new indoloditerpene asporyzin C (3), and three known related indoloditerpenes JBIR-03 (4), emindole SB (5), and emeniveol (6) were isolated from an endophytic fungus Aspergillus oryzae, isolated from the marine red alga Heterosiphonia japonica. Their structures were unambiguously established by spectroscopic techniques. In addition, all the isolates were evaluated preliminarily for insecticidal and antimicrobial activities in order to probe into their chemical defensive function. Compound 4 was more active against brine shrimp than the others, and 3 possessed potent activity against Escherichia coli.     

New cis-ent-clerodanes from Linaria japonica

Five new cis-ent-clerodanes, linarenones A–E (1–5) and two known compounds (6 and 7) were isolated from whole plant of Linaria japonica. The structures of these compounds were determined by various spectroscopic analyses (UV, IR, HR–ESI–MS, 1D and 2D NMR). The absolute configuration of five new diterpenoids was confirmed by circular dichroism (CD) analysis and chemical conversion. Cytotoxicity of the isolated compounds against A549 cell lines and Leishmania major were evaluated. The new cis-ent-clerodane 3 was found to be moderately active against A549 cell lines, and new cis-ent-clerodanes 1, 6 and desacetyl-linarienone (7) were active against L. major.     

Chemical constituents from the rhizome of Anemone hupehensis

A phytochemical investigation on the rhizome of Anemone hupehensis resulted in the isolation of thirteen compounds, including six neolignan glycosides (1-6), two phenylpropanoid glycosides (7, 8), a phenolic glycoside (9) and four triterpenoid saponins (10-13). The structures of the isolated compounds were elucidated on the basis of spectroscopic data. This is the first report of neolignan glycoside, phenylpropanoid glycoside, and phenolic glycoside from genus Anemone. This is also the first study to report compounds 1-5 and 7-9 from family Ranunculaceae. All the compounds, except 10 were isolated from A. hupehensis for the first time. The chemotaxonomic significance of the isolated compounds was discussed.     

Xanthone,benzophenone and bianthrone derivatives from the hypersaline lake-derived fungus Aspergillus wentii

Five new metabolites, including the xanthone derivative wentixanthone A (1), the benzophenone wentiphenone A (2), the diastereomeric mixtures of the bianthrones wentibianthrone A (3a, b) and wentibianthrone B (4a, b), as well as (10R,10′S)-wentibianthrone C (5a) and (10R,10′R)-wentibianthrone C (5b) were obtained from the fungus Aspergillus wentii, isolated from soil of the hypersaline lake El Hamra in Wadi El-Natrun, Egypt. The structures of the isolated compounds were established by one and two-dimensional NMR and MS spectroscopic analysis. The relative configuration of bianthrones (3–5) was elucidated by comparison of experimental and computed ¹H NMR chemical shifts. Results of biological assays are reported.     

The co-occurrence of bufadienolides and podophyllotoxins from Helleborus thibetanus

Phytochemical investigation of Helleborus thibetanus led to the isolation of two new bufadienolides with a trans A/B ring fusion mode (1–2) and two known ones (3–4), three podophyllotoxins (5–7), two flavones (8 and 9), one phytoecdysteroid (10), one spirostane (11) and one pseudo-spirostane (12). The structures of the new compounds were identified using extensive spectroscopic analyses and the known compounds were identified by comparing the spectral data with those previously reported. Isolation of bufadienolides with a trans A/B ring fusion mode could be chemotaxonomic marker for the differentiation of H. thibetanus from the toad venom and other plants of this genus, on the other hand, co-occurrence of podophyllotoxin from H. thibetanus supported the inclusion of Berberidaceae and Ranunculaceae in the same monophyletic order Ranunculales based on the outgroup comparison and parsimony analysis.     

Chemical constituents from the whole plant of Liparis japonica

A new lignanoid (1), together with six known lignanoids (2–7) and four known flavonoids (8–11), were isolated from the EtOAc extract of Liparis japonica. Their structures were determined by analyzing the HRESIMS, NMR, CD spectroscopic data, and comparing with the reported literatures. Among them, 1 was a new compound, 2–11 were first isolated from L. japonica and the genus of Liparis. The chemotaxonomic significance of these isolates was comprehensively discussed.