Alkyl phenols,alkenyl cyclohexenones and other phytochemical constituents from <Emphasis Type="Italic">Lannea rivae</Emphasis> (chiov) Sacleux (Anacardiaceae) and their bioactivity

Six novel compounds, 3-nonadec-14′-(Z)-enyl phenol (1a); 4,5-dihydroxy-4,2′-epoxy-5-[16′-Z-18′-E-heneicosenyldiene]-cyclohex-2-enone (2), 2,4,5-trihydroxy-2-[16′-Z-heneicosenyl]-cyclohexanone (3); 4S,6R-dihydroxy-6-[12′-Z-heptadecenyl]-cyclohex-2-enone (4a); 4S,6R-dihydroxy-6-[14′-Z-nonadecenyl]-cyclohex-2-enone (4b); and 1,2,4-trihydroxy-4-[16′-Z-heneicosenyl]-cyclohexane (5) were identified from the roots and stems of Lannea rivae in addition to the known cardanols, 3-heptadec-12′-Z-enyl phenol (1b), 3-pentadec-10′-Z-enyl phenol (1c) and 3-pentadecyl phenol (1d), sitosterol (6), sitosterol glucoside (7), taraxerone (8), taraxerol (9), E-lutein (10), myricetin (11), myricetin-3-O-α-rhamnopyranoside (12), myricetin-3-O-β-galactopyranoside (13) and (-)-epicatechin-3-O-gallate (14). The ketones 4a and 4b were isolated as a mixture and were qualitatively separated and identified by GCMS. Myricetin (11) and epicatechin gallate (14) displayed over 90 % DPPH radical-scavenging activity at 50 μg mL^?1, while its glycosides (12 and 13) showed percentages of over 70 % in the same assay. The same compounds 11 and 14 showed antibacterial activity similar to erythromycin and vancomycin against Gram-positive bacteria and were also active against Gram-negative bacteria, but not as much as the cefuroxime, ciprofloxacin and nalidixic acid standards. Compounds 1a–d, 4a–b and 5 were all relatively non-toxic, while 2 (the epoxy cyclohex-2-enone) and 3 (the trihydroxy cyclohexanone) showed more toxicity than the others. These two toxic compounds, 2 and 3 also showed antiplasmodial activity with IC₅₀ values between 0.48 and 2.05 μg mL^?1. The mixture of dihydroxy cyclohex-2-enones 4a and 4b, which was far less toxic than 2 and 3, also showed promising antiplasmodial activity and may be a possible lead for further investigation as an antiplasmodial drug.     

New ursane triterpenoids from <Emphasis Type="Italic">Ficus pandurata</Emphasis> and their binding affinity for human cannabinoid and opioid receptors

Phytochemical investigation of Ficus pandurata Hance (Moraceae) fruits has led to the isolation of two new triterpenoids, ficupanduratin A [1β-hydroxy-3β-acetoxy-11α-methoxy-urs-12-ene] (11) and ficupanduratin B [21α-hydroxy-3β-acetoxy-11α-methoxy-urs-12-ene] (17), along with 20 known compounds: α-amyrin acetate (1), α-amyrin (2), 3β-acetoxy-20-taraxasten-22-one (3), 3β-acetoxy-11α-methoxy-olean-12-ene (4), 3β-acetoxy-11α-methoxy-12-ursene (5), 11-oxo-α-amyrin acetate (6), 11-oxo-β-amyrin acetate (7), palmitic acid (8), stigmast-4,22-diene-3,6-dione (9), stigmast-4-ene-3,6-dione (10), stigmasterol (12), β-sitosterol (13), stigmast-22-ene-3,6-dione (14), stigmastane-3,6-dione (15), 3β,21β-dihydroxy-11α-methoxy-olean-12-ene (16), 3β-hydroxy-11α-methoxyurs-12-ene (18), 6-hydroxystigmast-4,22-diene-3-one (19), 6-hydroxystigmast-4-ene-3-one (20), 11α,21α-dihydroxy-3β-acetoxy-urs-12-ene (21), and β-sitosterol-3-O-β-d-glucopyranoside (22). Compound 21 is reported for the first time from a natural source. The structures of the 20 compounds were elucidated on the basis of IR, 1D (¹H and ¹³C), 2D (¹H–¹H COSY, HSQC, HMBC and NOESY) NMR and MS spectroscopic data, in addition to comparison with literature data. The isolated compounds were evaluated for their anti-microbial, anti-malarial, anti-leishmanial, and cytotoxic activities. In addition, their radioligand displacement affinity on opioid and cannabinoid receptors was assessed. Compounds 4, 11, and 15 exhibited good affinity towards the CB2 receptor, with displacement values of 69.7, 62.5 and 86.5 %, respectively. Furthermore, the binding mode of the active compounds in the active site of the CB2 cannabinoid receptors was investigated through molecular modelling.     

Anti-inflammatory activity of compounds from the rhizome of <Emphasis Type="Italic">Cnidium officinale</Emphasis>

Five new compounds, 9,3′-dimethoxyhierochin A (1), 6-oxo-trans-neocnidilide (2), (±)-(3E)-trans-6-hydroxy-7-methoxydihydroligustilide (3), (±)-cnidiumin (4), and 6-(1-oxopentyl)-salicylic acid methyl ester (5), together with twenty known compounds (6–25), were isolated from the rhizome of Cnidium officinale. The chemical structures of new compounds were established by NMR spectroscopic techniques, mass spectrometry, Mosher’s method, and CD spectrum. Their anti-inflammatory activities were evaluated against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in macrophage RAW 264.7 cells. Compounds 7, 13, and 14 showed inhibitory effects with IC₅₀ values of 5.1, 24.5, and 27.8 μM, respectively. In addition, compounds 7, 13, and 14 reduced LPS-induced inducible nitric oxide synthase (iNOS) expression and cyclooxygenase-2 (COX-2) protein in a concentration-dependent manner.     

Identification of cytoprotective constituents of the flower buds of <Emphasis Type="Italic">Tussilago farfara</Emphasis> against glucose oxidase-induced oxidative stress in mouse fibroblast NIH3T3 cells and human keratinocyte HaCaT cells

A new cytoprotective compound, 1-[(4S)-3,4-dihydro-4-hydroxy-2,2-dimethyl-2H-1-benzopyran-6-yl]-ethanone (1) was isolated from the flower buds of Tussilago farfara L. (Compositae), together with eight known compounds, 3,4-dicaffeoyl isoquinic acid (2), trans-cinnamic acid (3), 4-hydroxyacetophenone (4), 4,5-dicaffeoylquinic acid methyl ester (5), 3,5-dicaffeoylquinic acid methyl ester (6), 4-hydroxybenzoic acid (7), isoquercetrin (8), and ligucyperonol (9). Compounds 2–4 were found in this plant for the first time. The isolates 1–9, were tested for their cytoprotective activities against glucose oxidase-induced oxidative stress in mouse fibroblast NIH3T3 cells and human keratinocyte HaCaT cells. Among them, 1 and 3 showed significant cytoprotective activities as determined by MTT assay and lactate dehydrogenase leakage, indicating their possibility as the potent cytoprotective agents. The structure of 1 was determined by spectroscopic data analysis including 1D- and 2D-NMR experiments, and its absolute configuration was elucidated by a circular dichroism.     

Identification of new pyrrole alkaloids from the fruits of <Emphasis Type="Italic">Lycium chinense</Emphasis>

Three new minor pyrrole alkaloids, 3-[2-formyl-5-(hydroxymethyl)-1H-pyrrol-1-yl]pentanedioic acid (1), (2R)-[2-formyl-5-(hydroxymethyl)-1H-pyrrol-1-yl]-1-methoxy-1-oxobutanoic acid (2), and methyl (2R)-[2-formyl-5-(methoxymethyl)-1H-pyrrol-1-yl]-4-methylpentanoate (3) were isolated from the fruits of Lycium chinense Miller (Solanaceae), along with the known compound, methyl (2R)-[2-formyl-5-(methoxymethyl)-1H-pyrrol-1-yl]-3-(phenyl)propanoate (4). The structures of 1–4 were elucidated by analysis of their 1D- and 2D-NMR and HRMS data. The absolute configurations of 2–4, possessing a stereogenic center in each structure, were determined by comparison of their experimental electronic circular dichroism (ECD) with those of calculated ECD values.     

Synthesis of novel triazolyl pyranochromen-2(1<Emphasis Type="Italic">H</Emphasis>)-ones and their antibacterial activity evaluation

A series of thirty-three novel triazolyl pyranochromen-2(1H)-one derivatives have been synthesized via Cu (I) catalysed Huisgen 1,3-dipolar cycloaddition reaction. All of the synthesized compounds have been fully characterized from their spectral data and evaluated for antibacterial activity against both gram-positive and gram-negative bacteria. The activity results revealed that amongst all the compounds screened, six compounds, i.e. 2-[4-(((7-ethyl-2,2,6-trimethyl-8-oxo-2,3,4,8-tetrahydropyrano[3,2-g]chromen-10-yl)oxy)methyl)-1H-1,2,3-triazol-1-yl]acetic acid (41), 10-[(1-(1,3-dihydroxypropan-2-yl)-1H-1,2,3-triazol-4-yl)methoxy]-3-ethyl-4,8,8-trimethyl-7,8-dihydropyrano[3,2-g]chromen-2(6H)-one (44), 3-ethyl-4,8,8-trimethyl-10-[(1-((2R,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)-1H-1,2,3-triazol-4-yl)methoxy]-7,8-dihydropyrano[3,2-g]chromen-2(6H)-one (46), 2-[4-(((7-hexyl-2,2,6-trimethyl-8-oxo-2,3,4,8-tetrahydropyrano[3,2-g]chromen-10-yl)oxy)methyl)-1H-1,2,3-triazol-1-yl]acetic acid (52), 10-[(1-(1,3-dihydroxypropan-2-yl)-1H-1,2,3-triazol-4-yl)methoxy]-3-hexyl-4,8,8-trimethyl-7,8-dihydropyrano[3,2-g]chromen-2(6H)-one (55) and 3-hexyl-4,8,8-trimethyl-10-[(1-((2R,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)-1H-1,2,3-triazol-4-yl)methoxy]-7,8-dihydropyrano[3,2-g]chromen-2(6H)-one (57), exhibited moderate activity against all the strains studied with zone of inhibition between 10 and 16 mm and MIC values in the range of 75–170 µg/mL as compared to the standard used. The information obtained from structure–activity relationship can be used to design and develop the next generation of compounds with higher antibacterial efficacy.     

Phenylacylphenol derivatives with anti-melanogenic activity from <Emphasis Type="Italic">Stewartia pseudocamellia</Emphasis>

Three new phenylacylphenol derivatives, stewartianol (1), deoxystewartianol-4′-O-arabinoglucoside (2), and stewartianol-3-O-glucoside (3), along with nine known compounds, methylesculin (4), fraxoside (5), fraxetin (6), scopletin (7), (+)-dihydromyricetin (8), (+)-taxifolin-7-O-β-d-glucose (9), (+)-taxifolin (10), (+)-dihydrokaempferol-7-O-β-d-glucose (11), and 3-acetyl-ursolic acid (12), were isolated from the twigs of Stewartia pseudocamellia; commonly used as folk medicine in Korea. The structures of the isolated compounds were identified using spectroscopic analysis, including 1D, 2D NMR, MS and compared with published data. The compounds were tested for their anti-melanogenic activity in cultured murine B16 melanoma cells. Stewartianol (1) and stewartianol-3-O-glucoside (3) showed an inhibitory effect significantly on melanogenesis in a concentration-dependent manner.     

Degranulation inhibitors from the arils of <Emphasis Type="Italic">Myristica fragrans</Emphasis> in antigen-stimulated rat basophilic leukemia cells

A methanol extract of mace, the aril of Myristica fragrans (Myristicaceae), was found to inhibit the release of β-hexosaminidase, a marker of antigen-IgE-stimulated degranulation in rat basophilic leukemia cells (RBL-2H3, IC₅₀ = 45.7 μg/ml). From the extract, three new 8-O-4′ type neolignans, maceneolignans I–K (1–3), were isolated, and the stereostructures of 1–3 were elucidated based on spectroscopic and chemical evidence. Among the isolates, maceneolignans A (5), D (6), and H (8), (?)-(8R)-?^8′-4-hydroxy-3,3′,5′-trimethoxy-8-O-4′-neolignan (13), (?)-(8R)-?^8′-3,4,5,3′,5′-pentamethoxy-8-O-4′-neolignan (14), (?)-erythro-(7R,8S)-?^8′-7-acetoxy-3,4-methylenedioxy-3′,5′-dimethoxy-8-O-4′-neolignan (17), (+)-licarin A (20), nectandrin B (24), verrucosin (25), and malabaricone C (29) were investigated as possible degranulation inhibitors (IC₅₀ = 20.7–63.7 μM). These inhibitory activities were more potent than those of the antiallergic agents tranilast (282 μM) and ketotifen fumalate (158 μM). Compounds 5, 25, and 29 also inhibited antigen-stimulated tumor necrosis factor-α production (IC₅₀ = 39.5–51.2 μM), an important process in the late phase of type I allergic reactions.     

Anti-inflammatory effects of secondary metabolites isolated from the marine-derived fungal strain <Emphasis Type="Italic">Penicillium</Emphasis> sp. SF-5629

After the chemical investigation of the ethyl acetate extract of the marine-derived fungal strain Penicillium sp. SF-5629, the isolation and structural elucidation of eight secondary metabolites, including (3R,4S)-6,8-dihydroxy-3,4,7-trimethylisocoumarin (1), (3S,4S)-sclerotinin A (2), penicitrinone A (3), citrinin H1 (4), emodin (5), ω-hydroxyemodin (6), 8-hydroxy-6-methyl-9-oxo-9H-xanthene-1-carboxylate (7), and 3,8-dihydroxy-6-methyl-9-oxo-9H-xanthene-1-carboxylate (8) were carried out. Evaluation of the anti-inflammatory activity of these metabolites showed that 4 inhibited nitric oxide and prostaglandin E2 production in lipopolysaccharide-stimulated BV2 microglia, with IC₅₀ values of 8.1 ± 1.9 and 8.0 ± 2.8 μM, respectively. The inhibitory function of 4 was confirmed based on decreases in inducible nitric oxide synthesis and cyclooxygenase-2 gene expression. In addition, 4 was found to suppress the phosphorylation of inhibitor kappa B-α, interrupt the nuclear translocation of nuclear factor kappa B, and decrease the activation of p38 mitogen-activated protein kinase.     

Cinnamomulactone,a new butyrolactone from the twigs of <Emphasis Type="Italic">Cinnamomum cassia</Emphasis> and its inhibitory activity of matrix metalloproteinases

Cinnamomum cassia (Lauraceae) has long been used as one of the most frequently used traditional oriental medicines for the treatment of gastritis, diabetes, blood circulation disturbance and inflammatory diseases. Cinnamomulactone (1), a new butyrolactone was isolated from the twigs of C. cassia together with nine known compounds, coumarin (2), trans-cinnamic acid (3), cinnamaldehyde (4), 2-hydroxycinnamaldehyde (5), 2-methoxycinnamaldehyde (6), 2-hydroxy-cinnamyl alcohol (7), benzoic acid (8), (+)-syringaresinol (9) and phenethyl (E)-3-[4-methoxyphenyl]-2-propenoate (10). The planar structure of 1 was elucidated on the basis of spectroscopic data analysis and its configurations were determined by coupling constant (³ J _HH) analysis and a comparison with specific rotation data of related compounds on the literatures. The structures of known compounds were confirmed by the comparison of their spectroscopic data to the reported values. Compound 10 was isolated for the first time from this plant. Compounds 1, 2, 4, and 9 showed inhibitory activity against matrix metalloproteinases (MMPs) gene expression. Among them, compound 1 has been revealed to suppress the gene expression of MMP-3 and interleukin (IL)-1β as well as MMP-1 in tumor necrosis factor (TNF)-α stimulated rheumatoid arthritis synovial fibroblasts.     

New phenylpropanoids from <Emphasis Type="Italic">Bulbophyllum retusiusculum</Emphasis>

Two new phenylpropanoids, retusiusines A (1) and B (2), and a pair of new phenylpropyl enantiomers, (±)-retusiusine C (3a and 3b), together with eight known compounds, dihydroconiferyl dihydro-p-coumarate (4), methyl 3-(4-hydroxyphenyl) propionate (5), 3-(4-hydroxyphenyl)-propanoic acid (6), dihydroferulic acid (7), methyl 3-(4-methoxyphenyl) propionate (8), 3-(3,4-dimethoxyphenyl)-2-propenal (9), trans-p-coumaric acid (10) and dihydroconiferyl alcohol (11), were isolated from the tubers of Bulbophyllum retusiusculum. The absolute configurations of the new compounds were determined by calculating their electronic circular dichroism (ECD), spectra and specific optical rotations and comparing the calculated values with the experimental data. Compound 2 exhibited potent antifungal activity against Candida albicans (16 μg/mL). Compound 3 showed moderate antibacterial activity against Bacillus subtilis (64 μg/mL).     

Two new naphthalenic lactone glycosides from <Emphasis Type="Italic">Cassia obtusifolia</Emphasis> L. seeds

Two new naphthalenic lactone glycosides, (3S)-9,10-dihydroxy-7-methoxy-3-methyl-1-oxo-3,4-dihydro-1H-benzo[g]isochromene-3-carboxylic acid 9-O-β-d-glucopyranoside (1) and (3R)-cassialactone 9-O-β-d-glucopyranoside (2) were isolated from seeds of Cassia obtusifolia Linn., along with five known compounds: (3R)-cassialactone 9-O-β-d-gentiobioside (3), emodin 1-O-β-gentiobioside (4), 1-hydroxyl-2-acetyl-3,8-dimethoxy-naphthalene 6-O-β-d-apiofuranosyl-(1?→?2)-β-d-glucopyranoside (5), rubrofusarin 6-O-β-d-gentiobioside (6), rubrofusarin 6-O-β-d-triglucoside (7). Structures of 1 and 2 were elucidated by NMR and HR-ESI-MS spectroscopic analysis. Their stereochemistry was determined by CD experiment. All compounds were tested for their ability to inhibit the formation of advanced glycation end-products in vitro. Compounds 1, 2, 3, 5, and 6 showed significant in vitro inhibitory activities (IC₅₀ values of 11.63, 23.40, 7.32, 89.03, and 38.89 µM, respectively).     

A new indole glycoside from the seeds of <Emphasis Type="Italic">Raphanus sativus</Emphasis>

A new indole glycoside, β-d-glucopyranosyl 2-(methylthio)-1H-indole-3-carboxylate, named raphanuside A (1), as well as eight known compounds, β-d-fructofuranosyl-(2 → 1)-(6-O-sinapoyl)-α-d-glucopyranoside (2), (3-O-sinapoyl)-β-d-fructofuranosyl-(2 → 1)-α-d-glucopyranoside (3), (3-O-sinapoyl)-β-d-fructofuranosyl-(2 → 1)-(6-O-sinapoyl)-α-d-glucopyranoside (4), (3,4-O-disinapoyl)-β-d-fructofuranosyl-(2 → 1)-(6-O-sinapoyl)-α-d-glucopyranoside (5), isorhamnetin 3,4′-di-O-β-d-glucoside (6), isorhamnetin 3-O-β-d-glucoside-7-O-α-l-rhamnoside (7), isorhamnetin 3-O-β-d-glucoside (8) and 3'-O-methyl-(?)-epicatechin 7-O-β-d-glucoside (9) were isolated from the seeds of Raphanus sativus. Furthermore, compounds 1–3 and 6–9, were isolated from this plant for the first time. The structures of compounds 1–9 were identified using 1D and 2D NMR, including ¹H–¹H COSY, HSQC, HMBC and NOESY spectroscopic analyses. The inhibitory activity of these isolated compounds against interleukin-6 (IL-6) production in TNF-α stimulated MG-63 cells was also examined.     

Three new 5,6,7,8-tetrahydroxy-5,6,7,8-tetrahydrochromone derivatives enantiomeric to agarotetrol from agarwood

Agarwood (jinkoh in Japanese) is a resinous wood from Aquilaria species of the family Thymelaeaceae and has been used as incense and in traditional medicines. Characteristic chromone derivatives such as agarotetrol have been isolated from agarwood. In previous study, we isolated two new 2-(2-phenylethyl)chromones together with six known compounds from MeOH extract of agarwood. Further chemical investigation of the MeOH extract led to isolation of eighteen 2-(2-phenylethyl)chromones, including three new 5,6,7,8-tetrahydroxy-5,6,7,8-tetrahydrochromones with stereochemistry enantiomeric to agarotetrol-type, viz. (5R,6S,7S,8R)-2-[2-(3′-hydroxy-4′-methoxyphenyl)ethyl]-5,6,7,8-tetrahydroxy-5,6,7,8-tetrahydrochromone (2), (5R,6S,7S,8R)-2-[2-(4′-methoxyphenyl)ethyl]-5,6,7,8-tetrahydroxy-5,6,7,8-tetrahydrochromone (6), and (5R,6S,7S,8R)-2-[2-(4′-hydroxy-3′- methoxyphenyl)ethyl]-5,6,7,8-tetrahydroxy-5,6,7,8-tetrahydrochromone (13). The absolute configurations of the new compounds were determined by exciton chirality method. All isolated compounds were tested for their phosphodiesterase (PDE) 3A inhibitory activity by fluorescence polarization method. Compounds 8, 12–15, 21–24 showed moderate PDE 3A inhibitory activity.     

C<Subscript>21</Subscript> steroid derivatives from the Dai herbal medicine Dai-Bai-Jie,the dried roots of <Emphasis Type="Italic">Marsdenia tenacissima</Emphasis>, and their screening for anti-HIV activity

Twenty-three new C₂₁ steroidal glycosides, marstenacissides C1–C10 (1–10), D1–D7 (11–17) and E1–E6 (18–23), and four new C₂₁ steroids, 11α,12β-O-ditigloyl-tenacigenin C (24), 11α-O-benzoyl-12β-O-tigloyl-tenacigenin C (25), 11α-O-tigloyl-12β-O-benzoyl-tenacigenin C (26) and 11α-O-tigloyl-12β-O-benzoyl-marsdenin (27), were isolated from the Dai herbal medicine Dai-Bai-Jie, derived from the roots of Marsdenia tenacissima. The chemical structures of all compounds were established by spectroscopic techniques, including high-resolution mass spectrometry and NMR spectroscopy, as well as by comparison with reported spectral data. The anti-HIV activities of these compounds were screened, and the compounds obtained displayed inhibitory effects against HIV-1 with inhibition rates of 36.4–81.3% at 30 μM.     

Synthesis,antimicrobial and nematicidal evaluation of a new class of triazolo[4,3-<Emphasis Type="Italic">c</Emphasis>]quinazolinylthiazolidinones

In an attempt to find a new class of antimicrobial and nematicidal agents, a series of 2-aryl/heteryl-3-(5-phenyl[1,2,4]triazolo[4,3-c]quinazolin-3-yl)-1,3-thiazolidin-4-ones 5a-k was prepared by one-pot three-component reaction, involving 5-phenyl[1,2,4]triazolo[4,3-c]quinazolin-3-amine 4, aryl/heteroaryl aldehydes and thioglycolic acid, and characterized by physicochemical as well as spectral means. All the newly synthesized compounds 5a–k were tested in vitro for their antimicrobial activity against three representative Gram-positive (Bacillus subtilis, Staphylococcus aureus, Micrococcus luteus), Gram-negative (Proteus vulgaris, Salmonella typhimurium, Escherichia coli) bacteria and four fungal strains (Candida albicans, Aspergillus fumigatus, Trichophyton rubrum, Trichophyton mentagrophytes). These compounds 5a–k, were also evaluated for their nematicidal activity against two nematodes (Ditylenchus myceliophagus, Caenorhabditis elegans). Except phenyl substituted, all the ten aryl/heteroaryl substituted compounds 5b–k showed significant antimicrobial and nematicidal properties against tested microorganisms. Particularly, compounds 5b, 5c, 5g, 5h, 5j and 5k containing electron-withdrawing substituents like chlorophenyl, nitrophenyl, furyl and 1,3-benzodioxole exhibited promising activity comparable to employed standards Ampicillin, Amphotericin B and Levamisole, and emerged as potent antimicrobial and nematicidal agents.     

Chemical constituents from <Emphasis Type="Italic">Viburnum fordiae</Emphasis> Hance and their anti-inflammatory and antioxidant activities

Three new neolignans, fordianoles A-C (1–3), characterized as (7S,8R)-4-hydroxy-3,3′,5′-trimethoxy-8′,9′-dinor-8,4′-oxyneolignan-7,7′,9-triol, (7R,8R)-4-hydroxy-3,3′,5′-trimethoxy-8′,9′-dinor-8,4′-oxyneolignan-7,7′,9-triol, and (7R,8R)-4-hydroxy-3,3′,5′-trimethoxy-8,4′-oxyneolignan-7,9,9′-triol-7′-one, together with an unusual γ-lactone, 3-(3,4-dihydroxyphenyl)-4-pentanolide (4), and twenty-five known compounds (5–29) were isolated from the aerial parts of Viburnum fordiae Hance. Their structures including absolute configurations were determined by spectroscopic and chemical methods. Among them, compounds 6, 7, 11–15, 17–28 were isolated from the Viburnum genus for the first time. The anti-inflammatory and antioxidant activities of all compounds were evaluated in vitro. Compounds 15, 19, 20 and 29 showed significant inhibitory activity on NO production in RAW264.7 cells stimulated by LPS with IC₅₀ values ranging from 8.60 to 13.92 μM. Meanwhile, compounds 1–4, 15, 19, 20, 22, 23, 25, 26 and 29 exhibited varying antioxidant activities through DPPH, ABTS free radical scavenging and FRAP assays.     

Microbial transformation of naringenin derivatives

Microbial transformations of (±)-7-O-prenylnaringenin (7-PN, 1) and (±)-7-O-allylnaringenin (7-AN, 2) have isolated four metabolites (3–6). Structures of these novel compounds were identified as 5,4′-dihydroxy-7-O-[(2E)-4-hydroxy-3-methyl-2-buten-1-yl]flavanone (3), 5,4′-dihydroxy-7-O-(2,3-dihdroxy-3-methylbutyl)flavanone (4), 5,4′-dihydroxy-7-O-(2,3-dihdroxypropyl)flavanone (5), and 5-O-β-D-glucopyranosyl-7-O-allyl-4′-hydroxyflavanone (6) based on spectroscopy. Compounds 1–6 were evaluated for their radical scavenging capacity using DPPH (2,2-diphenyl-1-picrylhydrazyl). The derivatives 3–6 exhibited more potent antioxidant activity than their corresponding substrates 1 and 2.     

Anti-osteoclastogenic diacetylenic components of <Emphasis Type="Italic">Dendropanax morbifera</Emphasis>

Methanol (MeOH) extract of the aerial parts of Dendropanax morbifera (Araliaceae) has demonstrated a significant dose-dependent inhibitory effect on the RANKL-induced differentiation of bone marrow-derived macrophages to osteoclasts. Bioassay-guided fractionation of the extract resulted in the isolation of a novel diacetylene carboxylic acid (1), together with a known diacetylenic compounds (2) as phytochemicals to strongly inhibit the osteoclast differentiation. The chemical structure of 1 was determined by spectroscopic analyses as (9Z,16S)-16-O-acetyl-9,17-octadecadiene-12,14-diynoic acid, that is acetyl derivative of 2. Two diacetylenic components of D. morbifera, 1 and 2 exhibited a dose-dependent inhibitory effect on the RANKL-induced formation of tartrate-resistant acid phosphatase-positive multinucleated cells with IC₅₀ values of 2.4 and 3.1 μM, respectively. Seven other known components (3–9) were also isolated from the extract: dendropanoxide (3), friedelin (4), epifriedelanol (5), α-amyrin (6), β-amyrin (7), β-sitosterol (8), and stigmasterol (9). The significant anti-osteoclastogenic activities of 3, 4, 5, and 7 were first reported in this study.     

Design,synthesis, and evaluation of the anticonvulsant and antidepressant activities of pyrido[2,3-<Emphasis Type="Italic">d</Emphasis>]pyrimidine derivatives

A series of pyrido[2,3-d]pyrimidine derivatives (4a–4n, 5a–5n, 6, and 7) were designed and synthesized as potential anticonvulsants and antidepressants. Their pharmacological activities were evaluated by maximal electroshock test, forced swimming test, and tail suspension test in mice. Pharmacological analyses showed that compounds 4-benzyl-6,8-dimethylpyrido[3,2-e]tetrazolo[1,5-a]pyrimidin-5(4H)-one (4a) and 4-(3-fluorobenzyl)-6,8-dimethylpyrido[3,2-e]tetrazolo[1,5-a]pyrimidin-5(4H)-one (4e) exhibited the greatest anticonvulsant activity (PI 12.02 and 12.25, respectively, 30 min after intraperitoneal injection), and were more efficient than the reference drug, carbamazepine. In addition, 4-(4-fluorobenzyl)-6,8-dimethylpyrido[3,2-e]tetrazolo[1,5-a]pyrimidin-5(4H)-one (4f) and 6-(4-fluorobenzyl)-2,4-dimethylpyrido[3,2-e][1,2,4]triazolo[4,3-a]pyrimidin-5(6H)-one (5f) possessed potent antidepressant properties that lead to significant reduction in the duration of the immobility time than did the control (P < 0.001), which possessed activities similar to those of fluoxetine. 4f showed obvious antidepressant activity at doses of 10 mg/kg.