asebogenin and dihydrochalcone

One new dihydrochalcone diglycoside has been isolated from the EtOAc fraction of the Egyptian seagrass Thalassodendrin ciliatum (Forsk.) den Hartog, and was identified as 6'-O-rhamnosyl-(1‴ → 6″)-glucopyranosyl asebogenin for which a trivial name Thalassodendrone was established. Furthermore, five known phenolics were isolated and identified as asebotin, quercetin 3,7-diglucoside, protocatechuic acid, ferulic acid and p-hydroxybenzoic acid. The structures of all the isolated compounds were established based on 1D and 2D NMR spectroscopy and high-resolution-mass spectrometer. High-resolution electrospray ionization mass spectra (HR-ESI-MS) were obtained using a JEOL JMS-T100TD spectrometer (JEOL Ltd., Tokyo, Japan). The anti-influenza A virus activity of the isolated new compound and asebotin was evaluated, and the obtained results revealed that the inhibition dose concentration of asebotin was more than that of Thalassodendrone with IC50 = 2.00 and 1.96 μg/mL, respectively, and with cytotoxic concentration (CC50) of 3.36 and 3.14 μg/mL, respectively.

Topics: Alismatales; Animals; Antiviral Agents; Chalcones; Dogs; Egypt; Glycosides; Humans; Influenza A virus; Microbial Sensitivity Tests; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Oceans and Seas; Phenols; Quercetin

Six new dihydrochalcones, 3-hydroxyasebotin (5), asebogenin 2'-O-beta-D-ribohexo-3-ulopyranoside (6), 2' '-acetylasebotin (7), 3',4,5'-trihydroxy-4'-methoxydihydrochalcone 3',5'-di-O-beta-D-glucopyranoside (8), and pierotins A (9) and B (10), along with four known dihydrochalcones, phloretin (1), phlorizin (2), asebogenin (3), and asebotin (4), were isolated from the leaves of Pieris japonica. Their structures were elucidated on the basis of spectroscopic analysis including HMQC, HMBC, NOESY, and X-ray crystal diffraction. Compounds 1, 3-5, and 7-10 inhibited the proliferation of murine B cells and compounds 5 and 10 inhibited the proliferation of murine T cells in vitro significantly.

Topics: Animals; Chalcone; Chalcones; China; Crystallography, X-Ray; Drug Screening Assays, Antitumor; Ericaceae; Mice; Molecular Conformation; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Plant Leaves; Plants, Medicinal; T-Lymphocytes

Bioactivity-guided fractionation of an ethanolic extract of the leaves and twigs of Piper longicaudatum Trelease & Yunker (Piperaceae) resulted in the isolation of one new (1) and three known (2-4) dihydrochalcones. The known compounds are: 2',6'-dihydroxy-4'-methoxydihydrochalcone (2), 2',6',4-trihydroxy-4'-methoxydihydrochalcone (asebogenin) (3), and 2'-hydroxy-4'-methoxy-2'-[1-hydroxy-1-methylethyl]-2",3"-dihy- drofurano[4",5":5',6"]-3"-[2-hydroxy-5-methoxycarbonylphe- nyl]dihydrochalcone (piperaduncin B) (4). The new compound is 2'-hydroxy-4'-methoxy-2"-[2-hydroxy-5-methoxycarbonyl- phenyl]-furano[4",5":5',6']-dihydrochalcone (longicaudatin) (1). Compounds 1-4 were tested for antibacterial activity against S. aureus and methicillin-resistant S. aureus (MRSA); only compound 3 showed inhibitory activity (IC50 of 10 and 4.5 micrograms/ml, respectively).

Topics: Alkaloids; Anti-Bacterial Agents; Chalcone; Chalcones; Molecular Structure; Plant Leaves; Plant Stems; Plants, Medicinal; Staphylococcus aureus

Bioactivity-guided fractionation of a CH2Cl2 extract from the leaves of Piper aduncum afforded three new dihydrochalcones, piperaduncins A [3], B [4], and C [5], as well as two known dihydrochalcones, 2',6'-dihydroxy-4'-methoxydihydrochalcone [1] and 2',6',4-trihydroxy-4'-methoxydihydrochalcone [2] (asebogenin), together with sakuranetin, anodendroic acid methyl ester, and the carotenoid lutein. The structures of the isolates were elucidated by spectroscopic methods, mainly 1D- and 2D nmr spectroscopy. The proposed stereochemistry for compound 4 was deduced by NOESY spectroscopy and the corresponding energy minimum was established by molecular modelling calculations and translated into a 3D structure.

Topics: Animals; Anti-Bacterial Agents; Antineoplastic Agents, Phytogenic; Bacillus subtilis; Biomphalaria; Chalcone; Chalcones; Chromatography, Thin Layer; Computer Simulation; Drug Screening Assays, Antitumor; Escherichia coli; Humans; KB Cells; Magnetic Resonance Spectroscopy; Microbial Sensitivity Tests; Micrococcus luteus; Models, Molecular; Molecular Conformation; Molluscacides; New Guinea; Plant Extracts; Plants, Medicinal