RESUMEN
Five new compounds including, a neolignan, eupomatenoid-19 (1) and four polyoxygenated seco-cyclohexenes, artahongkongenes G-J (2-5), together with fifteen known compounds (6-20) were isolated from the stems and leaves of Piper suipigua Buch.-Ham. ex D. Don. Their structures were determined by spectroscopic evidence (IR, UV, 1H NMR, 13C NMR and 2 D NMR) as well as MS. The absolute configurations of polyoxygenated seco-cyclohexenes 2-8 were identified by NOESY data and by comparison of their experimental and calculated ECD spectral data. Neolignans, eupomatenoid-19 (1) and eupomatenoid-7 (10), displayed cytotoxicity against several cancer cell lines. In addition, eupomatenoid-7 (10) showed antibacterial activity against Bacillus cereus, Bacillus subtilis and Staphylococcus aureus.
Asunto(s)
Lignanos , Piper , Lignanos/farmacología , Lignanos/análisis , Piper/química , Ciclohexenos/análisis , Extractos Vegetales/química , Hojas de la Planta/química , Estructura MolecularRESUMEN
Three new furanoxanthones, macochinxanthones A-C (1-3) and sixteen known xanthones (4-19) were isolated from the roots of Maclura cochinchinensis. Their structures were elucidated by spectroscopic analysis including NMR, UV and IR, as well as mass spectrometry. Chiral-phase HPLC analysis of 1-3 revealed that they were scalemic mixtures with an enantiomeric excess (ee) of 0.05%, 36.8% and 8%, respectively. Most of the isolated xanthones exhibited potent cytotoxicity against four cancer cell lines (KB, HelaS3, A549 and HepG2) with IC50 values in the range of 1.29-90.15 µM. In addition, many of them displayed antibacterial activity against Gram-positive bacteria and Methicillin resistant Stephylococus aureus (MRSA) with MIC values in the range of 4-128 µg/mL.
Asunto(s)
Antineoplásicos , Maclura , Xantonas , Maclura/química , Xantonas/química , Extractos Vegetales/química , Raíces de Plantas/química , Antibacterianos/farmacología , Antibacterianos/análisis , Antineoplásicos/análisis , Estructura MolecularRESUMEN
The first phytochemical investigation from the stems of Croton krabas resulted in the isolation of three new ent-clerodane diterpenoids, crotonkrabases A-C (1-3), along with two known compounds, 12-oxohardwickiic acid (4) and crotonpyrone B (5). Their structures were elucidated using extensive spectroscopic methods. The structure of 3 was unambiguously proven by X-ray crystallography. Furthermore, the absolute configurations of compounds 1-3 were identified by NOESY and the comparison of their experimental ECD spectra with those of calculated ECD spectra reported in the literature. Compounds 1, 2, and 5 showed antibacterial activities against two Gram-positive bacteria (Bacillus cereus and Bacillus subtilis); whereas compound 4 exhibited weak antibacterial against B. cereus. In addition, compound 4 showed potent α-glucosidase inhibitory activity, which was lower than the reference standard acarbose.
Asunto(s)
Antibacterianos/farmacología , Croton/química , Diterpenos de Tipo Clerodano/farmacología , Inhibidores de Glicósido Hidrolasas/farmacología , Antibacterianos/aislamiento & purificación , Bacillus/efectos de los fármacos , Diterpenos de Tipo Clerodano/aislamiento & purificación , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Tallos de la Planta/química , TailandiaRESUMEN
Chromatographic separation of extracts from the fungal biomass of a plant pathogenic fungus, Myrothecium roridum, yielded 8 trichothecene toxins including 6 type D trichothecenes (1: -6: ) and 2 type A trichothecenes (7: -8: ). 6',12'-Epoxymyrotoxin A (1: ) and 7'-hydroxymytoxin B (2: ) were new macrocyclic trichothecenes, while the other trichothecenes were identified as myrotoxin B (3: ), myrotoxin D hydrate (4: ), 2',3'-epoxymyrothecine A (5: ), miotoxin A (6: ), and 2 trichothecenes lacking the macrocyclic lactone system, roridin L-2 (7: ) and trichoverritone (8: ). The structures of these mycotoxins were characterized using spectroscopic methods. The absolute configurations of 1: and 2: were determined by NOESY and a comparison of their experimental and calculated ECD spectra. Most of these mycotoxins (1: -4: and 6: ) exhibited highly potent antimalarial activity against Plasmodium falciparum. They also showed strong cytotoxicity towards KB and NCI-H187 cell lines (IC50 0.60â-â112.28 nM), as well as the Vero cell line (IC50 1.50â-â46.51 nM).
Asunto(s)
Antimaláricos/farmacología , Antineoplásicos/farmacología , Hypocreales/química , Micotoxinas/farmacología , Tricotecenos/química , Animales , Antimaláricos/química , Antineoplásicos/química , Línea Celular Tumoral , Chlorocebus aethiops , Evaluación Preclínica de Medicamentos , Concentración 50 Inhibidora , Espectroscopía de Resonancia Magnética , Estructura Molecular , Micotoxinas/química , Plasmodium falciparum/efectos de los fármacos , Relación Estructura-Actividad , Tricotecenos/farmacología , Células VeroRESUMEN
A new coruleoellagic acid derivative, 3,3',4,4',5'-pentamethylcoruleoellagic acid (1) together with nine known compounds, hexamethylcoruleoellagic acid (2), 3,4,3'-tri-O-methylellagic acid (3), heptaphylline (4), 7-methoxymukonal (5), dentatin (6), sinapaldehyde (7), gallic acid (8), 2,6-dimethoxy-4H-pyran-4-one (9) and ß-sitosterol (10) were isolated from the stems of Rhodamnia dumetorum. Their structures were identified by physical and spectroscopic data (IR, 1D and 2D NMR, and MS). Compounds 1, 2 and 7-10 were tested for antibacterial activity against six pathogenic bacterial strains (Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica serovar Typhimurium, Staphylococcus aureus, and Methicillin resistant S. aureus (MRSA)).