Publications by authors named "Praewpan Katrun"

A novel electrochemical sensor-based glassy carbon electrode (GCE) was fabricated and applied to simultaneous detection and degradation of tebuconazole (TBZ) for the first time. The GCE was consecutively modified by multi-walled carbon nanotubes (MWCNTs), bismuth oxybromide (BiOBr), ꞵ-cyclodextrin (ꞵ-CD), and in situ addition of tetrabutylammonium bromide (TBABr). The detection was based on the decreasing of Bi signal at its anodic potential (E) of 0.

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The electrophilic potential of vinyl sulfone permits the rapid capture of cysteine-containing proteins under physiological conditions. These cysteine proteinases play vital roles in bacterial survival and pathogenesis of Staphylococcus aureus (S. aureus) and the global health threat methicillin resistant S.

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Two new furan derivatives, annulofurans A-B (-), together with six known compounds were isolated from fungus. The structures were determined based on NMR and mass spectrometry data. The absolute configurations of annulofurans A-B were determined by Electronic Circular Dichroism (ECD) experiment and comparisons with the experimental ECD spectra of synthesized stereoisomers.

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Cholangiocarcinoma (CCA) is a major cause of mortality in Northeast Thailand with about 14,000 deaths each year. There is an urgent necessity for novel drug discovery to increase effective treatment possibilities. A recent study reported that lignin derived from can cause CCA cell inhibition.

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The ongoing search for anti-cancer agents from microorganisms led to the isolation of four new compounds including 6-ethyl-8-hydroxy-4-chromen-4-one (), 6-ethyl-7,8-dihydroxy-4-chromen-4-one (), (3)-3,4-dihydro-8-hydroxy-7-methoxy-3-methylisocoumarin () and (3)-3,4-dihydro-5,7,8-trihydroxy-3-methylisocoumarin (), together with eleven known compounds (-) from sp. SWUF09-62 fungus. The chemical structures were deduced from IR, 1D and 2D NMR, and MS data.

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A highly efficient and generally applicable iodine-catalyzed reaction of arylacetylenic acids and arylacetylenes with sodium sulfinates for the synthesis of arylacetylenic sulfones was developed. The methodology has the advantages of a metal-free strategy, easy to handle reagents, functional group tolerance, a wide range of arylacetylenic acids and arylacetylenes, and easy access to arylacetylenic sulfones.

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A highly efficient metal-free decarboxylative sulfonylation protocol for the preparation of (E)-vinyl sulfones from of β-aryl-α,β-unsaturated carboxylic acids using sodium sulfinates and (diacetoxyiodo)benzene (PhI(OAc)2) was developed. This strategy offers a simple and expedient synthesis of (E)-vinyl sulfones bearing a wide variety of functional groups. A radical-based pathway has been proposed for this decarboxylative sulfonylation reaction.

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A facile and general method for regioselective C2 sulfonylation reaction of indoles mediated by iodine is described. The 2-sulfonylated products were obtained up to 96% yield under mild reaction conditions (room temperature, 2 h).

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