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Marine natural products are promising sources of green antifoulants. Here, a new compound (1) was isolated from the soft coral Sinularia flexibilis. This compound, another nine cembranoids (2–10) from S. flexibilis, and three eunicellin-type diterpenoids (11–13) from the gorgonian Muricella sp. were tested for antifouling activity against larval settlement of the bryozoan Bugula neritina. Compounds 2, 3, 4, 9, 12, and 13 exhibited significant antifouling activity, with EC50 values of 18.2, 99.7, 67.9, 35.6, 33.9, and 49.3 μM, respectively. Analysis of the structure-activity relationships suggested that the hydroxy group at C-13 in compound 4 reduced its antifouling activity. [ABSTRACT FROM AUTHOR]

Four new steroidal saponins, 3-O-β-D-glucopyranosyl(1→4)-β-D-fucopyranosyl -(25R)-spirost-5-en-3β,17α-diol (1), 3-O-β-D-glucopyranosyl(1→4)-β-D- fucopyranosyl-(25S)-spirost-5-en-3β,17α-diol (2), 3-O-β-D-glucopyranosyl(1→2) -β-D-glucopyranosyl(1→4)-β-D-fucopyranosyl-(25R)-spirost-5-en-3β,17α-diol (3), 3-O-β-D-glucopyranosyl(1→4)-β-D-fucopyranosyl-(25R/S)-spirost-5-en-3β,12β-diol (4), together with five known steroidal saponins were isolated from the ethanolic extract of the rhizome of Polygonatum sibiricum. Chemical structures of these compounds were elucidated by spectroscopic techniques. Anti-inflammatory activities of these new compounds were evaluated. [ABSTRACT FROM AUTHOR]

Abstract: A new three‐dimensional graphene oxide‐wrapped melamine foam was prepared and used as a solid‐phase extraction substrate. β‐Cyclodextrin was fabricated onto the surface of three‐dimensional graphene oxide‐wrapped melamine foam by a chemical covalent interaction. In view of a specific surface area and a large delocalized π electron system of graphene oxide, in combination with a hydrophobic interior cavity and a hydrophilic peripheral face of β‐cyclodextrin, the prepared extraction material was proposed for the determination of flavonoids. In order to demonstrate the extraction properties of the as‐prepared material, the adsorption energies were theoretically calculated based on periodic density functional theory. Static‐state and dynamic‐state binding experiments were also investigated, which revealed the monolayer coverage of flavonoids onto the β‐cyclodextrin/graphene oxide‐wrapped melamine foams through the chemical adsorption. 1H NMR spectroscopy indicated the formation of flavonoids–β‐cyclodextrin inclusion complexes. Under the optimum conditions, the proposed method exhibited acceptable linear ranges (2–200 μg/L for rutin and quercetin‐3‐O‐rhamnoside; 5–200 μg/L for quercetin) with correlation coefficients ranging from 0.9979 to 0.9994. The batch‐to‐batch reproducibility (n = 5) was 3.5–6.8%. Finally, the as‐established method was satisfactorily applied for the determination of flavonoids in Lycium barbarum (Goji) samples with relative recoveries in the range of 77.9–102.6%. [ABSTRACT FROM AUTHOR]

A phytochemical investigation on gorgonianMuricellasp. from East China Sea resulted in the isolation of eight eunicellin diterpenoids including two new ones, muricellins A-B (1,2). Chemical structures of these compounds were elucidated by spectroscopic techniques (1D and 2D NMR and MS) and by comparison with data reported in the literature. Anti-rheumatoid arthritis activities of1,3,4, and6have been evaluated. [ABSTRACT FROM PUBLISHER]

Three new polyunsaturated lipids, (6Z,9Z,12Z,15Z)-octadeca-6,9,12,15-tetraen-3-one (1), (6Z,9Z,12Z,15Z)-1-bromooctadeca-6,9,12,15-tetraen-3-one (2), and (Z)-ethyl docos-5-enoate (3), together with two known polyunsaturated lipids, 4(Z),7(Z),10(Z)-tridecatrienoic acid (4) and (6Z,9Z,12Z,15Z)-octadeca-1,6,9,12,15-pentaen-3-one (5), were isolated from the marine sponge Haliclona sp., which was collected from Guangxi, using HSCCC and HPLC methods. Chemical structures of the five compounds were elucidated by spectroscopic techniques. [ABSTRACT FROM AUTHOR]

A chemical investigation of marine spongeJaspis stellifera, collected from the South China Sea, led to the isolation of four new isomalabaricane-type triterpenoids, jaspiferins C–F (1–4). The structures of those compounds were elucidated by extensive spectroscopic methods. Jaspiferin C (1), which has the six-membered carbon ring at the side chain, was discovered for the first time from the isomalabaricane-type triterpenoids. The hypothesis of a biogenetic pathway to generate jaspiferin C (1) was depicted. [ABSTRACT FROM PUBLISHER]

Three new pregnane alkaloids, named terminamines H–J (1–3), together with two known alkaloids (4 and 5), were isolated from the ethanol extract of Pachysandra terminalis. The structures of isolated compounds were elucidated by spectroscopic methods, including 1H and 13C NMR, 2D NMR, and HR-ESI-MS. Compounds 1, 4, and 5 revealed significant anti-metastasis activities. In addition, compound 1 inhibited the expression of p-PKCζ in MDA-MB-231 cells, and compound 4 inhibited the expressions of p-PKCζ in MDA-MB-231 and A549 cells. [ABSTRACT FROM AUTHOR]

The gorgonian Echinogorgia sassapo reticulata contains two new bioactive polyhydroxylated steroids, sassapols A (1), B (2), and five related known compounds (3–7). Compound 6 has been encountered for the first time in natural sources. The structures of these new compounds were defined by spectroscopic analysis. All the compounds (1–7) isolated from E. sassapo reticulata were tested for anti-inflammatory activity. Compounds 1, 3, 5, and 7 inhibited both the generation of leukotriene C4 and the degranulation reaction in mouse bone marrow-derived mast cells. [ABSTRACT FROM AUTHOR]

A chemical investigation of the endemic relict shrub Tetraena mongolica led to the isolation of four new triterpenes: 11α,12α:13β,28-diepoxyoleanane-3β-yl trans-caffeate (1), 3β-hydroxy-11α,12α-epoxyoleanane-28-al (2), olean-11-en-28-al-3β-yl trans-caffeate (3), and 28-acetoxy-olean-12-en-3β-yl trans-caffeate (4). Their structures were elucidated by extensive spectroscopic methods. [ABSTRACT FROM PUBLISHER]

Abstract: Four new flavonoids including three C-glycosidic flavonoids, named tetrastigma A–D (1–4) and five known flavones (5–9) were isolated from the herbs of Tetrastigma obtectum (Wall.) Planch. The structures of 1–4 were elucidated by 1D- and 2D-NMR and HR mass spectrometric methods. Compound 1 caused significant enhancement in glucose consumption by insulin-resistant HepG2 cells compared with control cells. In addition, compound 1 stimulated phosphorylation of AMPK, which plays an important role in glycometabolism. [Copyright &y& Elsevier]

A phytochemical research on the twigs of Dichapetalum longipetalum (Turcz.) Engl. Resulted in five undescribed dichapetalin-type triterpenoids 1 – 5. Their chemical structures were determined by spectroscopic analysis of HR-ESIMS and NMR spectra and the absolute configuration of compound 1 was completely elucidated by single crystal X-ray crystallography. Through preliminary anti-inflammatory activity assessment, compound 1 exhibited inhibitory effect on LPS-induced NO production in RAW264.7 murine macrophages with an IC 50 value of 2.09 μM. [Display omitted] • A phytochemical research on the twigs of Dichapetalum longipetalum (Turcz.) Engl. Resulted in five undescribed dichapetalin-type triterpenoids. • The absolute stereochemistry of compound 1 were confirmed by the single crystal X-ray diffraction. • Compounds 1 exhibited more potent inhibition against NO release with IC 50 of 2.09 μM than positive control dexamethasone. [ABSTRACT FROM AUTHOR]