RESUMO
The leaf extract of Suregada zanzibariensis gave two new modified ent-abietane diterpenoids, zanzibariolides A (1) and B (2), and two known triterpenoids, simiarenol (3) and ß-amyrin (4). The structures of the isolated compounds were elucidated based on NMR and MS data analysis. Single-crystal X-ray diffraction was used to establish the absolute configurations of compounds 1 and 2. The crude leaf extract inhibited the infectivity of herpes simplex virus 2 (HSV-2, IC50 11.5 µg/mL) and showed toxicity on African green monkey kidney (GMK AH1) cells at CC50 52 µg/mL. The isolated compounds 1-3 showed no anti-HSV-2 activity and exhibited insignificant toxicity against GMK AH1 cells at ≥100 µM.
Assuntos
Abietanos , Antivirais , Suregada , Triterpenos , Abietanos/química , Abietanos/isolamento & purificação , Abietanos/farmacologia , Animais , Antivirais/química , Antivirais/isolamento & purificação , Antivirais/farmacologia , Chlorocebus aethiops , Herpesvirus Humano 2/efeitos dos fármacos , Estrutura Molecular , Extratos Vegetais/química , Suregada/química , Triterpenos/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologiaRESUMO
The methanol root extract of Clerodendrum myricoides (Hochst.) Vatke afforded two new (1, 2) and two known (3, 4) iridoid glycosides. The structures of the isolated compounds were established based on NMR, IR, UV and MS data analyses. The crude extract and the isolated constituents were assayed for antiviral activity against the human respiratory syncytial virus (RSV) in human laryngeal epidermoid carcinoma (HEp-2) cells. The crude extract inhibited RSV infectivity at EC50 = 0.21 µg/ml, while it showed cytotoxicity against HEp-2 cells with CC50 = 9 µg/ml. Compound 2 showed 43.2% virus inhibition at 100 µM, while compounds 1 as well as 3 and 4 had only weak antiviral and cytotoxic activities.
Assuntos
Antivirais/farmacologia , Clerodendrum/química , Glicosídeos Iridoides/farmacologia , Vírus Sincicial Respiratório Humano/efeitos dos fármacos , Antivirais/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Glicosídeos Iridoides/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais , Raízes de Plantas/química , RuandaRESUMO
Two new prenylated dihydrochalcones (1,2) and eighteen known secondary metabolites (3-20) were isolated from the CH2Cl2-MeOH (1:1) extracts of the roots, the stem bark and the leaves of Eriosema montanum Baker f. (Leguminosae). The structures of the isolated compounds were characterized by NMR, IR, and UV spectroscopic and mass spectrometric analyses. The structures of compounds 5, 10, 11 and 13 were confirmed by single crystal X-ray diffraction. The antibacterial activity of the crude extracts and the isolated constituents were established against Gram-positive and Gram-negative bacteria. Among the tested compounds, 1-4 and 10 showed strong activity against the Gram-positive bacterium Bacillus subtilis with minimum inhibitory concentration (MIC) ranging from 3.1 to 8.9 µM, as did the leaf crude extract with an MIC of 3.0 µg/mL. None of the crude extracts nor the isolated compounds were active against Escherichia coli. Compounds 1, 3 and 4 showed higher cytotoxicity, evaluated against the human breast cancer cell line MCF-7, with EC50 of 7.0, 18.0 and 18.0 µM, respectively. These findings contribute to the phytochemical understanding of the genus Eriosema, and highlight the pharmaceutical potential of prenylated dihydrochalcones.