نتایج جستجو برای: spiro 4h pyran derivatives

تعداد نتایج: 113682  

2008
Song-Lei Zhu

In the mol-ecule of the title compound, C(20)H(10)BrN(3)O(4)·C(3)H(7)NO, the spiro pyran ring adopts a twist conformation. The indole and coumarin ring systems are each nearly planar, and are oriented at a dihedral angle of 79.29 (3)°. In the crystal structure, inter-molecular N-H⋯O, N-H⋯N, C-H⋯O and C-H⋯N hydrogen bonds link the mol-ecules.

Journal: :Bulletin of The Chemical Society of Ethiopia 2022

ABSTRACT. The aim of present study was the uses a series α,β-unsaturated carbonyl compounds (chalcones), in synthesis pyridine, pyran, thiophene, thiazole, together with their heterocyclic synthesis. work has resulted variety 2,5-dihydropyridine, hydrazide-hydrazone, thiophene derivatives, coumarin, pyran and thiazolo[4,5-d]thiazole derivatives. antitumor activities newly synthesized products w...

Journal: :Chemical communications 2014
Meng Li Xumeng Wu Yao Wang Yongsheng Li Weihong Zhu Tony D James

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.

Journal: :Molecules 2011
Gang Wang Fei Wang Ji-Kai Liu

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.

Journal: :Chemical & pharmaceutical bulletin 2012
Ryohei Okado Aya Nowaki Jun-Ichi Matsuo Hiroyuki Ishibashi

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...

2014
Yoshinobu Ishikawa Kohzoh Watanabe

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 ...

2013
Zeenat Fatima Thothadri Srinivasan Jonnalagadda Naga Siva Rao Raghavachary Raghunathan Devadasan Velmurugan

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...

Journal: :Acta Crystallographica Section E Structure Reports Online 2009

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید