Antimicrobial polyketides from the endophytic fungus Fusarium asiaticum QA-6 derived from medicinal plant Artemisia argyi.

Seven previously undescribed polyketide derivatives, fusariumtides A-G (1-7), together with three known analogues (8-10), were isolated from the culture extract of Fusarium asiaticum QA-6, an endophytic fungus obtained from the fresh stem tissue of the medicinal plant Artemisia argyi H. Lev. & Vaniot.

Isolation and Characterization of Antibacterial Carotane Sesquiterpenes from Associated Endophytic QA-8.

Carotane sesquiterpenes are commonly found in plants but are infrequently reported in the fungal kingdom. Chemical investigation of QA-8, an endophytic fungus associated with the inner root tissue of the grown medicinal herb H. Lév.

Polyketides and Terpenoids with Potent Antibacterial Activities from the Artemisia argyi-Derived Fungus Trichoderma koningiopsis QA-3.

The AcOEt extract of Artemisia argyi-derived fungus Trichoderma koningiopsis QA-3 showed potent inhibitory activity against pathogenic bacteria. Fractionation of the extract resulted in the isolation of three new polyketides (1-3) and two new terpenoids (4 and 5), together with three known metabolites (6-8). Their chemical structures were analyzed by NMR spectra, ECD, HR-ESI-MS or HR-EI-MS, optical rotation, and X-ray crystallographic data, as well as by comparison with literature reports.

Highly oxygenated polyketides produced by Trichoderma koningiopsis QA-3, an endophytic fungus obtained from the fresh roots of the medicinal plant Artemisia argyi.

Eight new highly oxygenated fungal polyketides, namely, 15-hydroxy-1,4,5,6-tetra-epi-koninginin G (1), 14-hydroxykoninginin E (2), koninginin U (3), 4'-hydroxykoninginin U (4), koninginin V (5), 14-ketokoninginin B (6), 14-hydroxykoninginin B (7), and 7-O-methylkoninginin B (8), together with six known related analogues (9-14), were isolated from Trichoderma koningiopsis QA-3, a fungus obtained from the inner root tissue of the well known medicinal plant Artemisia argyi. All these compounds are bicyclic polyketides, with compound 1 contains unusual hemiketal moiety at C-5 and compounds 2-14 having ketone group at C-1 and double bond at C-5(6). The structures and absolute configurations of the new compounds were established by spectroscopic analysis, X-ray crystal diffraction, modified Mosher's method, and ECD calculation.

Trichocadinins B-G: Antimicrobial Cadinane Sesquiterpenes from QA-8, an Endophytic Fungus Obtained from the Medicinal Plant .

Trichocadinins B-G (-), six new cadinane-type sesquiterpene derivatives, each with C-14 carboxyl functionality, were isolated from the culture extract of QA-8, an endophytic fungus obtained from the fresh inner tissue of the medicinal plant . Their structures were elucidated by interpretation of the NMR spectroscopic and mass spectrometric data. The structures and absolute configurations of compounds and were confirmed by X-ray crystallographic analysis.

Synthesis, photophysical and solvatochromic properties of diacetoxyboron complexes with curcumin derivatives.

Five novel diacetoxyboron complexes of β-diketones incorporated curcumin moiety were designed and synthesized. Their photophysical behaviors were investigated by UV-vis absorption and fluorescence spectroscopy in different solvents and solid state. It was observed that their fluorescence spectra yielded a blue to yellow-green emission in solution and emitted a yellow to red emission in solid state.

Preparation and photophysical properties of thienothiophene functionalized difluoroboron bis-β-diketonate complexes.

A series of six new thienothiophene functionalized difluoroboron bis-β-diketonates were synthesized and characterized. Their photophysical properties were investigated by UV-vis absorption, fluorescence spectroscopy and the method of CIE chromaticity in solution and powders. The results showed that these difluoroboron complexes yielded a blue-green emission at 474-500 nm in DMF solution and emitted a green to yellow emission at 541-587 nm in powders.

A highly sensitive fluorescent chemosensor for selective detection of zinc (II) ion based on the oxadiazole derivative.

A novel fluorescent chemosensor based on the oxadiazole, 2-(2-hydroxyphenyl)-5-(4-methoxyphenyl)-1,3,4-oxadiazole, was designed and synthesized. The interaction of the oxadiazole with different metal ions had been investigated through UV-vis absorption and fluorescence spectra in 9:1 (v/v) ethanol-water (pH=7.0) solution.

Fluorescence quenching study of 2,6-bis(5-(4-methylphenyl)-1-H-pyrazol-3-yl)pyridine with metal ions.

A novel bispyrazole derivative 2,6-bis(5-(4-methylphenyl)-1-H-pyrazol-3-yl)pyridine was synthesized and its structure was confirmed by (1)H NMR, FTIR, MS techniques and elemental analysis. The binding interactions of BMPP with Cd(2+), Co(2+), Pb(2+) and Cu(2+) ions were investigated in MeOH-H2O solution by fluorescence quenching technique at two temperatures (25 and 35°C). Their quenching constants KSV, binding constants K, binding sites n and thermodynamic parameters (ΔH, ΔG and ΔS) were determined.

Synthesis and spectroscopic properties of some new difluoroboron bis-β-diketonate derivatives.

Six new bis-β-diketones (RCOCH2CO-C7H7N-COCH2COR) were synthesized from 3,5-diacetyl-2,6-dimethylpyridine via Claisen condensation with the corresponding esters, and then reacted with boron trifluoride etherate to afford difluoroboron bis-β-diketonate derivatives. Their spectroscopic properties were investigated by UV-vis, FTIR, (1)H NMR and fluorescence spectroscopic techniques. It was found that these boron complexes exhibited violet or blue fluorescence emission at 422-445nm and possessed high extinction coefficients.

Synthesis, characterization and fluorescence properties of boron difluoride pyridyl-β-diketonate derivatives.

Five pyridyl-β-diketones were synthesized by Claisen condensation of ethyl nicotinate with various aryl methyl ketones in benzene in the presence of sodium amide as the base, and then reacted with boron trifluoride diethyl etherate in dichloromethane to afford some new boron difluoride pyridyl-β-diketonate derivatives. The compounds obtained were characterized using FTIR, (1)H NMR, elemental analysis and mass spectrometry. Their optical properties were studied in DMF by UV-vis absorption and fluorescence spectroscopy.

1-(4-Fluoro-phen-yl)-3-hydr-oxy-3-phenyl-prop-2-en-1-one.

In the crystal structure the title compound, C(15)H(11)FO(2), the molecule exists in the enol form. It is stabilized by an intra-molecular O-H⋯O hydrogen bond, in which the donor O-H and acceptor H⋯O distances are almost equal. The dihedral angle between the two benzene rings is 22.

3-[4-(Benz-yloxy)phen-yl]-1-(2-fur-yl)-3-hydroxy-prop-2-en-1-one.

In the crystal structure of the title compound, C(20)H(16)O(4), which is in the enol form, the central benzene ring makes dihedral angles of 63.42 (9) and 5.19 (10)° with the phenyl and furan rings, respectively.