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Abstract: Camptothecin (CPT), 9-methoxycamptothecin (9-MeO-CPT), and 10-hydroxycamptothecin (10-OH-CPT) are potent antineoplastic metabolites. We analyzed these metabolites in Camptotheca acuminata sampled from Germany and China, using LC–MS/MS and LC-ESI–HRMS/MS, coupled with chemometrics. Multivariate analysis revealed that fresh stems of C. acuminata from China had the highest comprehensive metabolite load. Significant positive correlations of CPT with 9-MeO-CPT and 10-OH-CPT were observed by Kruskal''s multidimensional scaling and principal component analysis. Linear discriminant analysis and hierarchical agglomerative cluster analysis revealed that C. acuminata from China was separated from others. These positive correlations indicate that these metabolites are biosynthesized similarly and operate synergistically in planta. [Copyright &y& Elsevier]

Chemical investigation of the roots of Entandrophragma congoënse (Meliaceae) led to the isolation of two new 3,4- seco -tirucallane triterpenes, namely seco -tiaminic acids B and C ( 1 and 2 ) together with nine known compounds: 3,4-secotirucalla-21-formyl-23-oxo-4(28),7,24-trien-3-oic acid ( 3 ), methyl angolensate ( 4 ), molucensin N ( 5 ), molucensin O ( 6 ), piscidinol A ( 7 ), 7 α ,20( S )-dihydroxy-4,24(28)-ergostadien-3-one ( 8 ), 24-methylene-cholest-5-en-3 β ,7 α -diol ( 9 ), entilin A ( 10 ), and entilin B ( 11 ). Their structures were determined using extensive spectroscopic methods including 1D and 2D NMR, HRMS, and CD analyses; new results were compared to existing data in the literature. The two newly identified seco -tiaminic acids showed moderate antiplasmodial and cytotoxic activities against a chloroquine-sensitive strain of the malaria parasite ( Plasmodium falciparum NF54) and were cytotoxic toward an L6 rat skeletal myoblast cell line, respectively. [ABSTRACT FROM AUTHOR]

Six new flavanones ( 1 – 6 ), together with six known compounds were isolated from Erythrina livingstoniana . Their structures were elucidated on the basis of NMR data and HRMS n fragmentation pathway and by comparison with literature data. Compounds 5 , 7 and 8 showed remarkable DPPH free radical scavenging efficacies. The compounds, however, did not demonstrate an anti-inflammatory potential when tested using a PGE 2 (prostaglandin E2) competitive enzyme immunoassay. The plausible biosynthetic pathways of the isolated compounds are described. [ABSTRACT FROM AUTHOR]

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]

Abstract: Investigation of the crude extract obtained from the aerial parts of Canthium multiflorum led to the isolation of a new iridoid (1) together with twelve known compounds. The structures of these compounds were elucidated by interpretation of 1D and 2D NMR spectroscopic data, accurate mass measurements and comparison with analytical data of previously known analogues. Most of the isolated compounds have been reported for the first time from C. multiflorium. The antimicrobial activities of the isolated compounds were evaluated on five different bacterial strains using agar diffusion technique. The Gram-positive bacterium Staphylococcus aureus subsp. aureus (DSM 799), and the Gram-negative bacteria Actinobacter calco-aceticus (DSM 30006), Serratia plymuthica (DSM 4540), Pseudomonas stutzeri (DSM 4166) and Escherichia coli (DSM 1116) were employed for this purpose. The new iridoid, named 6-oxo-genipin (1), demonstrated significant inhibitory activity against all microbial strains tested, especially the pathogen Staphylococcus aureus. In addition, the compounds 3, 4 and 9 exhibited antiplasmodial activity against Plasmodium falciparum strain K1 and weak cytotoxicity against L6 cell lines. [Copyright &y& Elsevier]

Abstract: A new hopene-type triterpenoid, namely sonhafouonic acid 1a was isolated from Zehneria scabra camerunensis, together with eight known compounds. The structure of 1a was established by extensive NMR and high resolution MS techniques and confirmed by single-crystal X-ray crystallographic analysis. Compound 1a exhibited inhibitory activity against mycelial growth of two peronosporomycete phytopathogens Pythium ultimum and Aphanomyces cochliodes and cytotoxicity towards brine shrimp larvae (Artemia salina) at 10μg/mL. [Copyright &y& Elsevier]