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Aerial parts of Carissa opaca have been investigated for the search of new bioactive secondary metabolites and a new nortriterpenoid: noropacursane (1) has been isolated together with three known compounds, namely, 6-methoxy-7-hydroxycoumarin (2), lupeol (3) and 4-ketopinoresinol (4). The structure of the new compound was established by 1D (¹H-, 13C-NMR), 2D-NMR (HMBC, HSQC, COSY and NOESY) and high resolution mass spectrometry (HR-EI-MS), where as the structures of the known compounds were elucidated through 1D-NMR, mass spectrometric analysis and compared with the reported data in literature. All the isolates were evaluated for their biological potential against the enzymes acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and lipoxygenase (LOX) as well as for DPPH free radical scavenging assays. Compound 4 was found active against DPPH radical scavenging activity and BChE with IC50 values of 83.41±0.17 and 101.81±0.24 μM, respectively, whereas compound 2 inhibited enzyme LOX with IC50 value of 102.25±0.17 μM. [ABSTRACT FROM AUTHOR]

Chromatographic purification of the ethyl acetate soluble fraction from the methanolic extract ofAtriplex lasianthayielded a new triterpenoid, 7β,15α,16β-trihydroxyolean-12-ene-28,30-dioic acid-3-O-β-d-xylopyranoside (1), along with two known triterpenoids, rotundifolioside I (2) and corchorusin B (3). Structures of the compounds1–3were elucidated through sophisticated NMR studies and high resolution mass spectrometry. The three isolates (1–3) were evaluated for antibacterial, antioxidant, and antiurease activities. Compound2exhibited the best antibacterial activity againstEscherichiacoliwith IC50value of 66.25 μg/ml, whereas, all the tested compounds exhibited antioxidant (IC50values of 68.7–75.4 μg/ml) and antiurease (IC50values of 25.5–49.3 μg/ml) activities, respectively. [ABSTRACT FROM PUBLISHER]

Two new cryptosporioptide-derived polyketides cryptosporioptides A (2) and B (3) were isolated from the extract of endophytic fungus Cryptosporiopsis sp. associated with the shrub, Viburnum tinus. The structures of the isolates were determined through spectral analysis including 1D NMR (1H, 13C) and 2D NMR (HSQC, HMBC, COSY) techniques, HR-FAB-MS and by comparison with the reported data of cryptosporioptide (1). The relative stereochemistry was assigned with the help of NOESY analysis, the molecular model, and comparison of the optical rotation values with the reference compound 1. [ABSTRACT FROM AUTHOR]

Chromatographic purification of ethyl acetate soluble fraction of the methanolic extract of the flowers ofAerva javanicayielded three new acylated flavone glycosides: kaempferol-3-O-β-d-[4‴-E-p-coumaroyl-α-l-rhamnosyl(1 → 6)]-galactoside (1), kaempferol-3-O-β-d-[4‴-E-p-coumaroyl-α-l-rhamnosyl(1 → 6)]-(3″-E-p-coumaroyl)galactoside (2), and kaempferol-3-O-β-d-[4‴-E-p-coumaroyl-α-l-rhamnosyl(1 → 6)]-(4″-E-p-coumaroyl)galactoside (3), along withp-coumaric acid (4), caffeic acid (5), gallic acid (6), eicosanyl-trans-p-coumarate (7), hexadecyl ferulate (8), and hexacosyl ferulate (9). The compounds1–9were characterized using 1D (1H,13C) and 2D NMR (HMQC, HMBC, and COSY) spectroscopy and mass spectrometry (EI-MS, HR-EI-MS, FAB-MS, and HR-FAB-MS) and in comparison with the reported data in the literature. Compound1showed weak inhibitory activity against enzymes, such as acetylcholinesterase, butyrylcholinesterase, and lipoxygenase with IC50values 205.1, 304.1, and 212.3 μM, respectively, whereas compounds2and3were only weakly active against the enzyme acetylcholinesterase. [ABSTRACT FROM PUBLISHER]

Four new sphingolipids: nudicaulin A [(2S,3S,4R,14E)-2-{[octadecanoyl]amino}tetraeicos-14-ene-1,3,4-triol; 1], nudicaulin B [(2S,3S,4R,14E)-2-{[(2R)-2-hydroxyoctadecanoyl]amino}tetraeicos-14-ene-1,3,4-triol; 2], nudicaulin C [(2S,3S,4R,14E)-2-{[(2R)-2-hydroxyoctadecanoyl]amino}tetraeicos-14-ene-1,3,4-triol-1-O-β-d-glucopyranoside; 3], and nudicaulin D [(2S,3S,4R)-2-{[(2R,3S,12E)-2,3-dihydroxyeicos-12-enoyl]amino}octadecane-1,3,4-triol; 4] together with 1-hexatriacontanol, β-sitosterol, octadecyl 4-hydroxycinnamate, elaidic acid, cholesta-5,22-diene-3,7-diol, oleanolic acid, apigenin, and β-sitosterol 3-O-β-d-glucopyranoside were isolated from the methanolic extract of the whole plant of Launaea nudicaulis. Their structures were elucidated using 1H and 13C NMR spectra and 2D NMR analyses (HMQC, HMBC, and COSY) in combination with mass spectrometry (EI-MS, HR-EI-MS, FAB-MS, and HR-FAB-MS) experiments and comparison with literature data of related compounds. Compounds 1–4 displayed moderate inhibitory potential against enzyme lipoxygenase in concentration-dependent manner with IC50 value ranges 103–193 μM. [ABSTRACT FROM AUTHOR]

Chromatographic purification of the methanolic extract of Plumeria obtusa yielded two new iridoid obtusadoids A (1) and B (2), along with eight known compounds plumieridin A (3), plumieridine (4), 1α-plumieride (5), 15-demethylplumieride (6), rel-(3R,3′S,4R,4′S)-3,3′,4,4′-tetrahydro-6,6′-dimethoxy[3,3′-bi-2H-benzopyran]-4,4′-diol (7), glochiflavanoside B (8), oleanolic acid (9), and methyl coumarate (10). The structures of all the isolates (1–10) were determined by NMR spectroscopy and mass spectrometry. The data of known compounds (3–10) were further compared with the reported data for these compounds. [ABSTRACT FROM PUBLISHER]

Chromatographic purification of the extract of an endophytic fungal culture yielded depsitinuside (1), a new phenolic ester together with ergosterol (2) and (22E,24S)-24-methyl-5-α-cholesta-7,22-diene-3β,5,6β-triol (3). The structure of 1 was elucidated based on 1D, 2D NMR spectroscopy and high-resolution mass spectrometry, whereas the known compounds (2 and 3) were identified by 1H NMR, mass spectrometry, and in comparison with the literature values. Compound 1 was evaluated for its enzyme inhibitory potential against acetylcholinesterase, butyrylcholinesterase and lipoxygenase, and was found inactive (10%–40% inhibition at a concentration of 2 mg/ml). [ABSTRACT FROM AUTHOR]

The variety 'Shukri' is a new hybrid of Citrus sinensis and is frequently grown for its sweet edible fruits in the southern part of Pakistan. The leaves of this hybrid variety have been investigated in search of secondary metabolites for the first time. As a result of chromatographic analysis of the methanolic extract, a new ceramide along with a flavonone glycoside and two steroids has been isolated, which were spectroscopically characterized as (E)-N-(1,3,4,5-tetrahydroxyhexadecan-2-yl)dec-4-enamide (1), atripliside B (2), β-sitosterol (3), and β-sitosterol-3-O-β-D-glucopyranoside (4), respectively. Compound 1 was found to be a new addition in the list of natural products, whereas, to the best of our knowledge, compounds 2-4 have been isolated for the first time from this source. [ABSTRACT FROM AUTHOR]