A series of 2-amino-4H-pyran-3-carbonitrile derivatives were designed and synthesized. Their antitubercular activities were evaluated against autoluminescent M. tuberculosis H37Ra and standard strain M. tuberculosis H37Rv. No obvious antitubercular activities could be observed (MIC > 10 g/mL). The results are in sharp contrast with the previously reported data.

An operationally simple and efficient protocol for the construction of dihydrofuran derivatives has been accomplished via a sequential addition of N-chlorosuccinimide and a base to 2-amino-4H-pyran derivatives in alcohol medium. The one-pot protocol proceeding via tandem oxidative difunctionalization and ring contraction provides an entirely new strategy for the construction of the dihydrofuran...

A novel near-infrared (NIR) and colorimetric fluorescent molecular probe based on a dicyanomethylene-4H-pyran chromophore for the selective detection of glutathione in living cells has been developed. The fluorescence OFF-ON switch is triggered by cleavage of the 2,4-dinitrobenzensulfonyl (DNBS) unit by the interaction with GSH.

Two new phenols, 2(S)-2',7-dihydroxy-5,8-dimethoxyflavanone and (S)-2-(4-hydroxyphenyl)-6-methyl-2,3-dihydro-4H-pyran-4-one, were isolated from the ethanol extract of Scutellaria barbata. Their structures were elucidated on the basis of spectroscopic analysis.

A catalytic amount of tin(IV) chloride catalyzed formal [4+2] cycloaddition reaction of di-tert-butyl 2-ethoxycyclobutane-1,1-carboxylate with ketones or aldehydes to give diethyl 6-ethoxydihydro-2H-pyran-3,3(4H)-dicarboxylates, whereas two equivalents of trimethylsilyl triflate promoted tandem [4+2] cycloaddition and lactonization to afford 3-oxo-2,6-dioxabicyclo[2.2.2]octane-4-carboxylate est...

In the title hydrate, C19H16N2O4·H2O, the 4H-chromen-4-one segment is slightly twisted, with a dihedral angle between the two six-membered rings of 3.30 (5)°. The dihedral angles between the plane of the pyran-one ring and the hydrazide plane and between the planes of the pyran-one ring and the benzene ring of the p-meth-oxy-benzene unit are 26.69 (4) and 2.23 (3)°, respectively. The mol-ecule ...

In the title compound, C20H18O7, the dioxolane ring adopts an envelope conformation with the dimethyl-substituted C atom as the flap, and its mean plane makes a dihedral angle of 73.25 (2)° with the pyran ring mean plane. The furan ring makes dihedral angles of 67.43 (12) and 6.20 (11)° with the mean plane of the dioxolane and pyran rings, respectively. The O atom attached to the pyran ring dev...

Abstract Recent studies have shown that p‐type polymeric semiconductors enable a new type of wireless, optically triggered interface with cells and tissues. Poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) has already been used to create such optobioelectronic interfaces, producing reactive oxygen species hydrogen peroxide act as messengers in biological systems impact cell signaling proliferation. Howev...