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Extracts of Chlorophora regia are frequently used in Ghana in traditional medicine. There is, however, no reported data on the chemical composition of the plant. Comprehensive phytochemical investigation of the stem bark of C. regia resulted in the isolation of three new prenylated 2-arylbenzofuran derivatives, regiafuran A–C ( 1–3 ), and one new prenylated flavonol ( 4 ), together with fifteen known compounds ( 5–19 ). Their structures were elucidated by combined spectroscopic analysis of their NMR and HRESI-MS n data. Compounds 1, 2, 5, 9 and 15 exhibited remarkable free radical scavenging properties with IC 50 values of 1.9 μg/ml, 2.4 μg/ml, 2.2 μg/ml, 2.1 μg/ml and 1.8 μg/ml, respectively, compared to the standard trolox (IC 50 1.1 μg/ml). The isolated compounds did not, however, show any anti-inflammatory potential when tested using a PGE 2 (prostaglandin E 2 ) competitive enzyme immunoassay. [ABSTRACT FROM AUTHOR]

Phytochemical investigation of the stem bark extract of Anopyxis klaineana was carried out by various chromatographic techniques resulting in the isolation and characterization of three new tirucallane triterpenoids, namely 3,23-dioxotirucalla-7,24-dien-21-oic acid ( 1 ), 3,4-secotirucalla-23-oxo-4(28)7,24-trien-3,21-dioic acid ( 2 ) and 3,4-secotirucalla-4-hydroxy-23-oxo-7,24-diene-3,21-dioic acid-21-methyl ester ( 3 ), along with nine known compounds ( 4–12 ). The structural elucidation of the compounds was performed by means of high-resolution mass spectrometry (HRMS n ), nuclear magnetic resonance (NMR), and by comparison to literature data. Although none of the isolated compounds showed antibacterial efficacy against selected environmental and clinically important pathogenic Gram-positive and -negative bacteria, they demonstrated moderate DPPH free radical scavenging properties. Furthermore, compounds 1 and 7 exhibited remarkable anti-inflammatory potential in a prostaglandin E 2 (PGE 2 ) competitive enzyme immunoassay with IC 50 values of 3.63 μM and 10.23 μM, respectively. [ABSTRACT FROM AUTHOR]

The chemical study of Erythrina livingstoniana has led to the isolation of three new flavanones namely 5,7,3′-trihydroxy-4′-methoxy-5′-formylflavanone (erylivingstone A) ( 1 ), 5,7,3′-trihydroxy-5′-(2-hydroxy-3-methylbut-3-enyl)-4′-methoxyflavanone (erylivingstone B) ( 2 ) and 5,7,3′-trihydroxy-5′-(3-hydroxy-3-methyl- trans -but-1-enyl)-4′-methoxyflavanone (erylivingstone C) ( 3 ) together with three known compounds ( 4 – 6 ). Their structures were elucidated on the basis of NMR data, HRMS n fragmentation pathway and by comparison with literature data. We evaluated the antibacterial efficacies and free-radical scavenging potential of the isolated compounds ( 1 – 6 ). The typical environmental strains of Gram-positive Bacillus subtilis , Gram-negative Escherichia coli , as well as against the clinically important Staphylococcus aureus , Streptococcus pyogenes and E. coli (risk-group 2) were used for the antibacterial assay. Compounds 5 and 6 exhibited the most pronounced efficacy against tested environmental bacteria as well as against the pathogenic strain of E. coli . Compound 3 was also quite active against these three bacterial strains. The isolated compounds showed weak radical scavenging properties with compound 6 being the most active, followed by compounds 2 , 3 and 5 . [ABSTRACT FROM AUTHOR]

Bioassay guided fractionation of Hypericum riparium leaves extract has resulted in the isolation and characterization of three new compounds namely chipericumin E ( 1 ), hyperenone C ( 3 ), and hyperixanthone ( 5 ), together with twenty known compounds. Their structures were elucidated based on comprehensive interpretation of spectroscopic and spectrometric data. Compounds 1 – 4 , and 6 – 8 displayed moderate antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) and cytotoxic effects on the human gastric cell line BGC-823 with IC 50 values ranging from 6.54 to 18.50 μM. [ABSTRACT FROM AUTHOR]

Two new tirucallane-type triterpenoids were isolated from the bark of Entandrophragma congoënse (Meliaceae) along with five known compounds gladoral A, bipendensin, 4-hydroxymethyl-3,5-dimethyldihydrofuran-2(3 H )-one, scopoletin and 5,7-dimethoxy-6-hydroxycoumarin. Their structures were elucidated by means of spectroscopic analyses including 1D and 2D-NMR spectroscopy, high resolution mass spectrometric data as well as the comparison of data with those reported in the literature. The tested compounds ( 1 – 4 ) displayed moderated antiplasmodial activity against erythrocytic stages of chloroquine-resistant Plasmodium falciparum strain NF54 and low cytotoxicity on L6 cell lines. All the isolated compounds are reported for the first time from the genus Entandrophragma. [ABSTRACT FROM AUTHOR]