A new sulfonylated flavonoid and other bioactive compounds isolated from the aerial parts of <i>Cotula anthemoides</i> L.

<p>A new sulfonyl flavonol glucoside, 5,7,4′,5′-tetrahydoxyflavonol 2′-[propanoic acid-(2″′-acetoxy-1″′-sulfonyl)]-5′-O-β-d-glucopyranoside (<b>1</b>) was isolated from the aerial parts of <i>Cotula anthemoides</i> L. in addition to 15 known compounds (<b>2</b>–<b>16</b>). The structure elucidation of these compounds was based on analyses of spectroscopic data including 1D-, 2D-NMR and HR-ESI-MS techniques and by comparing their NMR data with those reported in the literature. These compounds were evaluated for their DPPH radical scavenging and tyrosinase inhibitory activity. Compound <b>6</b> showed a high DPPH radical scavenging with EC₅₀ value of 9.1 ± 0.4 μM. Compound <b>11</b>, <b>9</b> and <b>1</b> exhibited a mild tyrosinase inhibitory activity with IC₅₀ values of 85 ± 0.8, 95 ± 1.5 and 100 ± 0.5 μM, respectively.</p

Abietane diterpenes from the cones of <i>Abies numidica</i> de Lannoy ex Carrière (Pinaceae) and <i>in vitro</i> evaluation of their antimicrobial properties

<p>Eight known abietane diterpenes (<b>1</b>–<b>8</b>) were isolated for the first time from <i>Abies numidica</i> cones (Pinaceae)<i>.</i> The structures of all compounds were established by means of 1D and 2D NMR, and UV spectral analyses. The hydromethanolic extract of <i>A. numidica</i> cones was tested for its antimicrobial activity against 17 gram-positive and gram-negative bacteria and against five yeasts by the use of liquid and solid medium and bioautography methods. The best antimicrobial activity was found against gram-positive bacteria (MIC ≤ 0.3 mg/mL) <i>Bacillus subtilis, Enterococcus faecalis</i> ATCC 1034, <i>Staphylococcus aureus</i> 8325.4, <i>S. aureus</i> CIP 53.154, <i>Micrococcus luteus</i> and <i>Listeria innocua</i> and against <i>Candida</i> yeasts. The determination of MIC’s of isolated products showed a high activity of compounds <b>4</b> and <b>6</b> against <i>S. aureus, L. innocua</i> (MIC = 62.5 μg/mL) and <i>E. faecalis</i> (MIC = 125 μg/mL).</p

A new triterpene saponin and known compounds from the polar extract of <i>Salvia argentea</i> L. and evaluation of their antioxidant activity

A new triterpene saponin, 2, 3, 21, 23-tetrahydroxyolean-12-en-28-oic-acid-28-O-β-D- glucosyl-(2’’→1’)-β-D-glucoside (1), was isolated from the n-butanol extract of dried aerial parts of Salvia argentea L. (Lamiaceae) in addition to two known flavonoids, apigenin 7-O-β-D-glucoside (2), threo-guaiacylglycerol 3-O-[6-O-p-hydroxybenzoyl]-β-D-glucoside (3), luteolin 7-O-β-D-glucoside (4), verbascoside (5) and rosmarinic acid (6). The structure elucidation of these compounds was based on analyses of spectroscopic data including 1D-, 2D-NMR and HR-ESI-MS techniques and by comparing their NMR data with those reported in the literature. Compound 6 exhibited the highest antioxidant activity in DPPH assay (IC50<3.00 µg/mL) which was better than the standards BHA, BHT, Trolox and ascorbic acid.</p

Phytochemical profiles and evaluation of the biological potential of ethyl acetate and <i>n</i>-butanol fractions of the aerial parts of <i>Cistus albidus</i> L

The phytochemical profiles of the ethyl acetate (EAFCA) and n-butanol (BFCA) fractions of the aerial parts of Cistus albidus L., were characterised by a developed LC-ESI-MS/MS method, using 53 fingerprint phytochemicals, revealing the presence of 26 and 22 compounds, respectively with quinic acid, gallic acid, protocatechuic acid, catechin, gentisic acid, tannic acid, ellagic acid, quercitrin, astragalin as the major compounds of the EAFCA, in very higher amounts than in the BFCA. The antioxidant activity was evaluated using six methods (DPPH•, ABTS•+, GOR•, CUPRAC, FRAP and Phenanthroline). In agreement with its highest polyphenolic content (430.12 ± 1.02 µg GAE/mg of extract) and largest amounts of identified polyphenolics, the EAFCA exhibited a higher antioxidant activity than the BFCA. Additionally, the EAFCA showed the highest acetylcholinesterase (AChE) inhibition (IC50 of 25.1 ± 2.58 µg/mL). Moreover, both EAFCA and BFCA demonstrated high photoprotective activity, with sun protection factor (SPF) values of 36.49 and 36.52, respectively.</p

Isolation and characterisation of cytotoxic compounds from <i>Euphorbia clementei</i> Boiss.

<p>A new phorbol-type diterpene ester, 4,20-dideoxy-4<i>α</i>-phorbol-12<i>β</i>-acetate-13<i>α</i>-isobutyrate, in addition to 11 known compounds were isolated from the latex and roots of <i>Euphorbia clementei</i> Boiss. Structure elucidation was performed by comprehensive 1D and 2D NMR analyses (¹H and ¹³C NMR, COSY, ROESY, HSQC and HMBC experiments), mass spectrometry (HR-ESI-MS) and by comparison with literature data. The inhibitory activity of all isolated compounds was evaluated against promyelocytic leukemia HL60 and human erythromyeloblastoid leukemia K562 cell lines and seven of these compounds exhibited a weak cytotoxicity with IC₅₀ values ranging from 40 to 97 μM.</p

A new 2-alkylhydroquinone glucoside from <i>Phagnalon saxatile</i> (L.) Cass

<p>A new 2-alkylhydroquinone glucoside, 1-<i>O</i>-<i>β</i>-d-glucopyranosyl-1,4-dihydroxy-2-((<i>E</i>) 2-oxo-3-butenyl)benzene (<b>1</b>), in addition to nine known compounds were isolated from the aerial parts of <i>Phagnalon saxatile</i> (L.) Cass. (Asteraceae). Their structures were identified based on spectroscopic methods including 1D and 2D NMR, mass spectrometry (HR-ESI-MS), UV spectral analyses and by comparison with literature data. The cytotoxic activity of three isolated compounds (<b>1–3</b>) was evaluated against fibrosarcoma (HT1080), human lung cancer (A549) and breast cancer (MCF7) cell lines.</p

Chemical composition and antioxidant activity of aerial parts of <i>Ferula longipes</i> Coss. ex Bonnier and Maury

<p>This is the first study on the phytochemistry and antioxidant activity of <i>Ferula longipes</i> Coss. ex Bonnier and Maury (Apiaceae). A new flavonoid quercetin-3-<i>O</i>-<i>α</i>-L-rhamnopyranoside-7-O-<i>ß</i>-D-[2-O-caffeoyl]-glucopyranoside (<b>1</b>), along with 10 known compounds kaempferol-3-<i>O</i>-<i>α</i>-L-rhamnopyranoside (<b>2</b>), quercetin-3-<i>O</i>-<i>α</i>-L-rhamnopyranoside (<b>3</b>), kaempferol-3-<i>O</i>-<i>ß</i>-D-glucopyranoside-7-<i>O</i>-<i>α</i>-L-rhamnopyranoside (<b>4</b>), isorhamnetin-3-<i>O</i>-<i>α</i>-L-rhamnopyranoside-7-<i>O</i>-<i>ß</i>-D-glucopyranoside (<b>5</b>), quercetin-3-<i>O</i>-<i>α</i>-L-rhamnopyranoside-7-<i>O</i>-<i>ß</i>-D-glucopyranoside (<b>6</b>), isorhamnetin-3,7-di-<i>O</i>-<i>β</i>-D-glucopyranoside (<b>7</b>), apigenin (<b>8</b>), apigenin-7-<i>O</i>-<i>ß</i>-D-glucopyranoside (<b>9</b>), 3,5-dicaffeoylquinic acid (<b>10</b>), deltoin (<b>11</b>) were isolated from the aerial parts of <i>Ferula longipes</i> Coss. Structures elucidation was performed by comprehensive 1D and 2D NMR analyses, mass spectrometry and by comparison with literature data. The compounds <b>1</b>, <b>3</b>, <b>4</b>, <b>6</b>, <b>7</b> and <b>10</b> were evaluated for their antioxidant activity, compound <b>1</b> exhibited the best antiradical activity potential and showed IC₅₀ and A_0.5 values 5.70, 7.25, 5.00, and 2.63 μg/mL towards DPPH free radical-scavenging, ABTS, CUPRAC, and reducing power assays, respectively compared with BHA, BHT and ascorbic acid which were used as positive controls.</p

Antibacterial, antioxidant and cytotoxic activities of triterpenes and flavonoids from the aerial parts of <i>Salvia barrelieri</i> Etl.

<p>From the aerial parts of <i>Salvia barrelieri</i> Etl. (Lamiaceae), 12 compounds including a new triterpene, 3<i>β</i>-acetoxy-olean-18-ene-2<i>α</i>-ol, were isolated. Their structures were established by the combination analyses of spectroscopy including 1D-, 2D-NMR and HRESIMS and in comparison with the reported data in the literature. The antibacterial activity of these compounds was evaluated by bioautography on <i>Staphylococcus aureus</i> followed by the determination of MIC values by serial dilution technique against five bacteria. Three compounds were active against <i>Enterococcus faecalis</i>, <i>S. aureus</i>, <i>Staphylococcus epidermidis, Escherichia coli</i> and <i>Pseudomonas aeruginosa</i> (MIC 15.1 to 125 μg/mL). Two compounds showed moderate DPPH radical scavenging activity (IC₅₀ 79.1 and 21.2 μg/mL). These compounds did not show significant tyrosinase inhibitory activities (IC_50> 1.5 mg/mL). Their cytotoxic activity was evaluated against promyelocytic leukaemia (HL60), human erythromyeloblastoid leukaemia (K562) and fibrosarcoma (HT1080) cell lines and four compounds exhibited a moderate cytotoxic activity (IC₅₀ 28.75 to 85.0 μM).</p

Isoquinoline Derivatives via Stepwise Regioselective sp² and sp³ C–H Bond Functionalizations

Efficient and practically attractive stepwise ruthenium- and palladium-catalyzed regioselective C–H bond functionalizations were achieved to produce 4-substituted tetrahydroisoquinoline derivatives featuring various heteroaromatic substructures in moderate to good yields. Both ruthenium- and palladium-based catalytic processes generated nontoxic and easily separable side products

Cytotoxic triterpenes from <i>Salvia buchananii</i> roots

<p>A pentacyclic triterpene, named salvibuchanic acid (<b>1</b>), together with five known compounds, were isolated from the roots of <i>Salvia buchananii</i> Hedge (Lamiaceae). The structural characterisation of all compounds was performed by spectroscopic analyses, including 1D and 2D NMR and HRESIMS experiments. The lupane triterpene (<b>1</b>) and hyptadienic acid (<b>2</b>) were investigated for their potential cytotoxic activity on Jurkat, HeLa and MCF7 cell lines. Both compounds showed an interesting antiproliferative activity with similar potency in all cell lines. By means of flow cytometric studies, hyptadienic acid (<b>2</b>) induced in HeLa cells a S cell cycle block, while <b>1</b> elicited both cytostatic and cytotoxic responses.</p