ABSTRACT
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.
Subject(s)
Lignans , Piper , Lignans/pharmacology , Lignans/analysis , Piper/chemistry , Cyclohexenes/analysis , Plant Extracts/chemistry , Plant Leaves/chemistry , Molecular StructureABSTRACT
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.
Subject(s)
Antineoplastic Agents , Maclura , Xanthones , Maclura/chemistry , Xanthones/chemistry , Plant Extracts/chemistry , Plant Roots/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/analysis , Antineoplastic Agents/analysis , Molecular StructureABSTRACT
A new juvenile hormone III, canangalia I (1), along with six known juvenile hormone III analogues (2-7), was isolated from the methanolic extract of Cananga latifolia stems. All structures were elucidated using spectroscopic data and compared with data from previous literature. Canangalia I (1) was found to be cytotoxic against human cervical adenocarcinoma (HeLa) cells with an IC50 value of 35.00 ± 2.15 µg/ml after 72 h, but was not toxic to Vero cells.
Subject(s)
Cananga , Sesquiterpenes , Chlorocebus aethiops , Animals , Humans , Cananga/chemistry , Vero Cells , Molecular Structure , Sesquiterpenes/chemistryABSTRACT
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.
Subject(s)
Anti-Bacterial Agents/pharmacology , Croton/chemistry , Diterpenes, Clerodane/pharmacology , Glycoside Hydrolase Inhibitors/pharmacology , Anti-Bacterial Agents/isolation & purification , Bacillus/drug effects , Diterpenes, Clerodane/isolation & purification , Glycoside Hydrolase Inhibitors/isolation & purification , Phytochemicals/isolation & purification , Phytochemicals/pharmacology , Plant Stems/chemistry , ThailandABSTRACT
An unprecedented nickel-catalyzed decarbonylative silylation via CO extrusion intramolecular recombination fragment coupling of unstrained and nondirecting group-assisted silyl ketones is described. The inexpensive and readily available catalyst performs under mild reaction conditions and enables the synthesis of structurally diverse arylsilanes, including heterocyclic and natural product derivatives.
ABSTRACT
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).
Subject(s)
Antimalarials/pharmacology , Antineoplastic Agents/pharmacology , Hypocreales/chemistry , Mycotoxins/pharmacology , Trichothecenes/chemistry , Animals , Antimalarials/chemistry , Antineoplastic Agents/chemistry , Cell Line, Tumor , Chlorocebus aethiops , Drug Evaluation, Preclinical , Inhibitory Concentration 50 , Magnetic Resonance Spectroscopy , Molecular Structure , Mycotoxins/chemistry , Plasmodium falciparum/drug effects , Structure-Activity Relationship , Trichothecenes/pharmacology , Vero CellsABSTRACT
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)).
Subject(s)
Anti-Bacterial Agents/chemistry , Ellagic Acid/analogs & derivatives , Ellagic Acid/chemistry , Myrtaceae/chemistry , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Bacillus cereus/drug effects , Drug Evaluation, Preclinical/methods , Ellagic Acid/isolation & purification , Ellagic Acid/pharmacology , Escherichia coli/drug effects , Magnetic Resonance Spectroscopy , Methicillin-Resistant Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Molecular Structure , Plant Stems/chemistry , Pseudomonas aeruginosa/drug effects , Salmonella typhimurium/drug effects , Staphylococcus aureus/drug effectsABSTRACT
A revised structure of colossolactone G (1), seven new triterpene lactones, ganodermalactones A-G (2-8), and five known triterpene lactones, colossolactone I (9), schisanlactone B (10), colossolactone B (11), colossolactone E (12), and colossolactone IV (13), and ergosterol have been isolated from cultured biomass of the macrofungi Ganoderma sp. KM01. Their structures were identified by spectroscopic methods. Structures and relative configurations of 3, 7, and 8 were confirmed by X-ray crystallographic analysis. Compounds 7, 10, and 12 exhibited antimalarial activity against Plasmodium falciparum in the range 6.0-10.0 µM (IC50).
Subject(s)
Antimalarials/chemistry , Antimalarials/isolation & purification , Ganoderma/chemistry , Lactones/isolation & purification , Plasmodium falciparum/drug effects , Triterpenes/chemistry , Triterpenes/isolation & purification , Antimalarials/pharmacology , Crystallography, X-Ray , Fruiting Bodies, Fungal/chemistry , Lactones/chemistry , Molecular Conformation , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Thailand , Triterpenes/pharmacologyABSTRACT
Phytochemical investigation of the roots of Leea thorelii led to the isolation of nine compounds. Their structures were determined from spectroscopic data as bergenin (1), 11-O-acetyl bergenin (2), 11-O-(4'-O-methylgalloyl) bergenin (3), 3,5-dihydroxy-4-methoxybenzoic acid (4), ( - )-epicatechin (5), 4"-O-methyl-( - )-epicatechin gallate (6), ( - )-epicatechin gallate (7), microminutinin (8) and stigmasterol. Compounds 1-8 are reported for the first time from this plant, and this is also the first report of the presence of 1, 3, 4, 6 and 8 in the Vitaceae family.