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.     

Two new glycosides from the whole plant of Anemone rivularis var. flore-minore

Phytochemical investigation on the whole plant of Anemone rivularis var. flore-minore led to the isolation of a new labdane-type diterpene glycoside (1) and a new trihydroxyfuranoid lignanoid glycoside (2), together with three known triterpene and triterpenoid glycosides (3–5). The structures of the two new compounds were elucidated as β-d-glucopyranosyl (13S)-13-hydroxy-7-oxo-labda-8,14-diene-18-oate (1) and (7S,7′R,8R,8′S)-7′-butoxy-7,9′-epoxy-4,4′,9-trihydroxy-3,3′-dimethoxylignane 9-O-β-d-glucopyranoside (2), on the basis of extensive spectral analysis and chemical evidence. Compound 1 is characterized by a glucose (Glc) esterified C-18 carboxyl group, which is a rarely encountered labdane-type diterpene glycoside in nature. The two new compounds (1 and 2) reported here are the first examples of diterpene glycoside and lignanoid glycoside found in the genus Anemone, and the known triterpene and triterpenoid glycosides (3–5) are identified for the first time from the title plant.     

New flavonoids from the fruits of Cornus mas,Cornaceae

One new β-hydroxychalcone, 4-acetoxy-5,2′,4′,6′,β-pentahydroxy-3-methoxychalcone (1), one new flavanone, 7,3′-dihydroxy-5,4′-dimethoxyflavanone (2) and seven known compounds, 2R, 3R-trans-aromadendrin (3), naringenin-7-O-methylether (4), myricetin (5), quercetin-3-O-rutinoside (6), ursolic acid (7), gallic acid (8) and d-glucose (9) were isolated from the methanolic fruit extract of Cornus mas L. (=Cornus mascula L.), Cornaceae. The structures of the new compounds were elucidated on the basis of extensive spectroscopic methods, including 2D NMR experiments and of known compounds by comparison of physical and spectral data with literature.     

Acylated flavonol glycosides and δ-truxinate derivative from the aerial parts of Lysimachia clethroides

Phytochemical investigation of the aerial parts of Lysimachia clethroides led to the isolation of a new acylated flavonol glycoside (1) and a new δ-truxinate derivative (2), together with three known acylated flavonol glycosides. The structures of the new compounds were determined by spectroscopic methods and chemical evidence as quercetin-3-O-β-d-(6-O-Z-p-coumaroyl)glucopyranoside (1) and monomethyl 3,3′,4,4′-tetrahydroxy-δ-truxinate (2), respectively. All of the isolates were evaluated for their in vitro inhibitory activity against aldose reductase.     

Quinic acid derivatives and coumarin glycoside from the roots and stems of Erycibe obtusifolia

A new quinic acid derivative (1) and a new coumarin glycoside (8), together with six known compounds (2–7) were isolated from the roots and stems of Erycibe obtusifolia. The structures of the new compounds were elucidated by spectroscopic and chemical analyses. The in vitro antiviral activity against the respiratory syncytial virus (RSV) of seven quinic acid derivatives was evaluated by cytopathic effect (CPE) reduction assay. Among them, the dicaffeoylquinic acids (6 and 7) displayed potent in vitro anti-RSV activity.     

Serratezomines D and E,new Lycopodium alkaloids from Lycopodium serratum var. serratum

Two new Lycopodium alkaloids, serratezomines D (1) and E (2), were isolated from the club moss Lycopodium serratum var. serratum. Serratezomine D (1) is a new lucidine-type alkaloid, while serratezomine E (2) is a new phlegmarane-type alkaloid. The structures and relative stereochemistry of 1 and 2 were elucidated on the basis of spectroscopic data. Serratezomine D (1) exhibited an inhibitory activity against acetylcholinesterase.     

Four new iridoid glucoside p-coumaroyl esters from Ajuga decumbens

From the methanolic extract of the dried whole plant ofAjuga decumbens, four new iridoid glucosidecis- andtrans-p-coumaroyl esters, decumbeside A (1), B (2), C (7) and D (8) were isolated together with the known reptoside (6) and 8-acetylharpagide (9). The structures of the new compounds have been elucidated on the basis of spectroscopic and chemical evidence.     

Bioactive new withanolides from the cultured soft coral Sinularia brassica

Continuing study of the ethyl acetate (EtOAc) extract of the cultured soft coral Sinularia brassica afforded five new withanolides, sinubrasolides H–L (1–5). The structures of the new compounds were elucidated on the basis of spectroscopic analysis. The cytotoxicities of new compounds 1–5 and a known compound sinubrasolide A (6) against the proliferation of a limited panel of cancer cell lines were assayed. The anti-inflammatory activities of compounds 1–6 were evaluated by measuring their ability to suppress N-formyl-methionyl-leucyl-phenyl-alanine/cytochalasin B (fMLP/CB)-induced superoxide anion generation and elastase release in human neutrophils.     

Sesquiterpenoids from the Chinese endangered plant Manglietia aromatica

One new bourbonane-type (1) and one new cadinane-type (2) sesquiterpenoids, along with one known aromodendrane-type (3) and five known megastigmane-type (4–8) compounds, were isolated from the leaves and twigs of Manglietia aromatica, a Chinese endangered plant that has not been previously phytochemically investigated. The structures and absolute configurations of the new isolates, (1R,4S,5S,6S,7S,10S)-4-hydroxy-bourbon-8-one (1) and (1R,6S,7S)-1-hydroxy- cadin-4,9-dien-8-one (2), were established by means of spectroscopic methods and a combination of experimental and calculated electronic circular dichroism (ECD). Among the isolates, compound 2 was found to show a moderate inhibitory effect against the human protein tyrosine phosphatase 1 B (PTP1B) enzyme, a target for the treatment of type-II diabetes and obesity, with an IC₅₀ value of 83.5 μM.     

Flavonoid glycosides from the aerial parts of Curcuma comosa

Four new flavonoid glycosides, curcucomosides A–D (1–4), three known flavonoid glycosides, 5–7, and four known diarylheptanoids, 8–11, were isolated from the ethanol extract of the aerial parts of Curcuma comosa. The structures of the new compounds were established as rhamnazin 3-O-α-l-arabinopyranoside (1), rhamnocitrin 3-O-α-l-arabinopyranoside (2), rhamnazin 3-O-α-l-rhamnopyranosyl-(1→2)-O-α-l-arabinopyranoside (3), and rhamnocitrin 3-O-α-l-rhamnopyranosyl-(1→2)-O-α-l-arabinopyranoside (4) by spectroscopic analysis and chemical reactions whereas those of the known compounds were identified by spectral comparison with those of the reported values.     

Diterpenoids from the root bark of Jatropha curcas and their cytotoxic activities

Three new diterpenoids, named epi-jatrophol (1), jatrophaldehyde (2) and epi-jatrophaldehyde (3), along with nine known ones (4–12), were isolated from the root bark of Jatropha curcas. The new compounds were identified by spectroscopic data, and their relative configurations were confirmed by X-ray crystallography or chemical methods. The cytotoxic activities of the isolated compounds were evaluated against HEPG2 and LOVO tumor cell lines. Compounds 8, 9 and 10 were found to be cytotoxic toward HEPG2 cells for the first time.     

Cytosporones,coumarins, and an alkaloid from the endophytic fungus Pestalotiopsis sp. isolated from the Chinese mangrove plant Rhizophora mucronata

Chemical examination of the endophytic fungus Pestalotiopsis sp., isolated from the leaves of the Chinese mangrove Rhizophora mucronata, yielded 11 new compounds including cytosporones J–N (1–3, 5–6), five new coumarins pestalasins A–E (8–12), and a new alkaloid named pestalotiopsoid A (14), along with the known compounds cytosporone C (4), dothiorelone B (7), and 3-hydroxymethyl-6,8-dimethoxycoumarin (13). The structures of the new compounds were unambiguously elucidated on the basis of extensive spectroscopic data analysis.     

Chromone acyl glucosides and an ayanin glucoside from Dasiphora parvifolia

Two new chromone acyl glucosides, 5-hydroxy-7-O-(6-O-p-cis-coumaroyl-β-D-glucopyranosyl)-chromone (1) and 5-hydroxy-7-O-(6-O-p-trans-coumaroyl-β-D-glucopyranosyl)-chromone (2), and a new flavonoid glucoside, ayanin 3′-O-β-D-glucopyranoside (3) were isolated from aerial parts of Dasiphora parvifolia, together with flavonoid glycosides (4–10), catechins (11, 12), and hydrolysable tannins (13, 14). The chemical structures of these compounds were elucidated on the basis of spectroscopic data. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and the hyaluronidase inhibitory activity of these compounds were evaluated.     

Three new glycosides from the whole plant of Clematis lasiandra Maxim and their cytotoxicity

Phytochemical investigation on the whole plant of Clematis lasiandra Maxim led to the isolation of two new phenolic glycosides (1 and 2), one new lignanoid glycoside (3), together with three known lignanoid glycosides (4–6). The structures of the new compounds were elucidated as 4-O-β-d-galactopyranosyl-ethyl-E-caffeate (1), 4-O-β-d-galactopyranosyl-3-hydroxyl-phenylethene (2) and (8R)-3,3′-dimethoxy-4,4′,9,9′-tetrahydroxy-5′,8-lignan 3′-O-β-d-glucopyranoside (3), on the basis of extensive spectral analysis and chemical evidence. The characteristic of the polymerized C-5′–C-8 type lignanoid aglycone in glycoside 3 was found from genus Clematis for the first time. Compounds 1–6 were evaluated for their cytotoxicity against human tumor cell lines HL-60, Hep-G2 and SGC-7901, the new glycosides 1 and 2 showed significant cytotoxicity against those three tumor cell lines with IC₅₀ in the range from 9.73 to 22.31 μM, while lignanoid glycosides 3–6 showed weak cytotoxicity to those test cell lines with IC₅₀ value more than 52.71 μM.     

An antibacterial cytochalasin derivative from the marine-derived fungus Diaporthaceae sp. PSU-SP2/4

A new pentacyclic cytochalasin (diaporthalasin, 1) and a new ethyl trihydroxytridecatrienoate (diaporthacol, 2) together with five known compounds, R-mevalonolactone (4), dothiorelone C (5), (4S,7S,13S)-4,7-dihydroxy-1,3-tetradeca-1,5-dienolide (6), 4β-acetoxy-9β,10β,15α-trihydroxyprobotrydial (7) and O-methyldihydrobotrydial (8) were isolated from the marine-derived fungus Diaporthaceae sp. PSU-SP2/4. The structures were established by spectroscopic techniques. Compound 1 displayed significant antibacterial activity against both Staphylococcus aureus and methicillin-resistant S. aureus with equal MIC values of 2 μg/mL.     

Cytotoxic quinazoline alkaloids from the seeds of Peganum harmala

Seventeen quinazoline alkaloids and derivatives, containing two pairs of new epimers, named as (S)- and (R)-1-(2-aminobenzyl)-3-hydroxypyrrolidin-2-one β-d-glucopyranosyl-(1?→?6)-β-d-glucopyranoside (1, 2), (S)- and (R)-vasicinone β-d-glucopyranosyl-(1?→?6)-β-d-glucopyranoside (3, 4), and a new enantiomer (12b), together with six known ones (5–8, 10, and 12a), and three pairs of known enantiomers (9, 11, and 13), were isolated from the ethanol extracts of the seeds of Peganum harmala L.. Their structures including the absolute configuration were elucidated by using 1D and 2D NMR, and ECD calculation approaches. The cytotoxic activities of all isolated compounds were evaluated. 11 showed moderate cytotoxicity against PC-3 cells with an IC₅₀ value of 15.41?μM.     

Strophasterols E and F: Rearranged ergostane-type sterols from Pleurotus eryngii

Strophasterols E (1) and F (2) were isolated from the fruiting bodies of Pleurotus eryngii, together with four new ergostane-type sterols (3–6). Single-crystal X-ray diffraction analysis performed on the tris-p-bromobenzoate derivatives of compounds 1 and 2 allowed these two compounds to be identified as the structurally rare (22S,23R)- and (22S,23S)-5α,6α-epoxy-3β,7β,23-trihydroxy-15(14 → 22)-abeo-ergost-8-en-14-one, respectively. The inhibitory effects on nitric oxide production of the six new steroids thus isolated from the fruiting bodies of P. eryngii were also evaluated.     

Two new aporphine alkaloids with glucose consumption increasing activity from Cassytha filiformis

Two new aporphine alkaloids, named precassythine (1) and (+)− 6S-ocotecine-N-oxide (2), were isolated from Cassytha filiformis. The new structures were elucidated by applying various spectroscopic techniques, including 1D-, ²D NMR and HRESIMS. The absolute configurations of 1 and 2 were determined by calculated electronic circular dichroism (ECD). Both compounds were evaluated for their effects on glucose consumption on HL-7702 cells at different concentrations. The results showed that the two new compounds significantly increased glucose consumption.     

Three new cucurbitane triterpenoids from Hemsleya penxianensis and their cytotoxic activities

Two new cucurbitane glycosides, hemslepenside A (1) and 16,25-O-diacetyl-cucurbitacin F-2-O-β-d-glucopyranoside (3), one new cucurbitacin, 16-O-acetyl-cucurbitacin F (2), along with three known cucurbitane compounds, were isolated from the roots of Hemsleya penxianensis. The structures of 1–6 were established on the basis of extensive spectroscopic and chemical methods. The isolated compounds were evaluated for their cytotoxic activities against different three human cancer cell lines, with IC₅₀ values in the low microgram range.     

Isolation and characterization of the chemical constituents from Plumeria rubra

Rubranonoside (=7-O-α-l-rhamnopyranosyl-4′-O-β-d-glucopyranosylnaringenin; (1), a new flavanone glycoside, rubranin (=(2S,3S,4R)-2-{[(2R,16E)-2-hydroxyhexaeico-16-en]amino}octadecane-1,3,4-triol-1-O-β-d-glucopyranoside; (2), a new sphingolipid, rubradoid (plumieridine-1-O-β-d-galactopyranoside; (3), a new iridoid galactoside, rubrajaleelol (4) and rubrajaleelic acid (5), two new nor-terpenoids together with known iridoids: 1-α-plumieride (6), plumieride p-Z-coumarate (7) and plumieride-p-E-coumarate (8) have been isolated from the EtOAc-soluble fraction of the MeOH extract of Plumeria rubra. Their structures were assigned from ¹H, ¹³C NMR spectra and 2D NMR analyses (COSY, NOESY, HMQC and HMBC experiments) in combination with HRMS experiments and comparison with literature data of related compounds. All the isolates (1–8) were tested for their antioxidant, antiurease, cytotoxic and phytotoxic activities and were found almost inactive.