نتایج جستجو برای: chromene

تعداد نتایج: 842  

2014
Rajeswari Gangadharan Jebiti Haribabu Ramasamy Karvembu K. Sethusankar

In the title compound, C17H20ClN3OS, the mean plane of the central thio-urea core makes dihedral angles of 26.56 (9) and 47.62 (12)° with the mean planes of the chromene moiety and the cyclo-hexyl ring, respectively. The cyclo-hexyl ring adopts a chair conformation. The N-H atoms of the thio-urea unit adopt an anti conformation. The chromene group is positioned trans, whereas the cyclo-hexyl ri...

2012
Al-Anood M. Al-Dies Abdel-Galil E. Amr Ahmed M. El-Agrody Tze Shyang Chia Hoong-Kun Fun

In the title mol-ecule, C(21)H(15)FN(2)O(2), the dihedral angle between the fluoro-substituted benzene ring and the mean plane of the 4H-benzo[h]chromene ring system [maximum deviation = 0.109 (2) Å] is 83.35 (7)°. The pyran ring adopts a slight sofa conformation with the tertiary C(H) atom forming the flap. The meth-oxy group is slightly twisted from the attached benzene ring of the 4H-benzo[h...

Journal: :Bulletin of The Chemical Society of Ethiopia 2022

ABSTRACT. The versatile scaffold, N'-(2-cyanoacetyl)-2-hydroxybenzohydrazide (3) was utilized in the production of new pyridine, chromene and thiazole derivatives as antimicrobial antioxidant agents. synthetic strategy involves treatment precursor 3 with various arylidene-malononitrile 3-aryl-2-cyanoacrylate compounds to furnish substituted pyridines 5 7. interaction salicylaldehyde and/or phen...

2010
M. Vindu Vahini H. C. Devarajegowda K. M. Mahadevan T. G. Meenakshi H. K. Arunkashi

In the title compound, C(16)H(12)O(4), the chromene ring system is almost planar [maximum deviation = 0.026 (1) Å] and makes dihedral angles of 1.24 (9) and 26.5 (2)° with the fused benzene ring and the plane of the ethyl carboxyl-ate group, respectively.

2012
Sunayna Pawar Adele Cheddie Bernard Omondi Neil Anthony Koorbanally

In the title compound, C(18)H(20)O(4),the pyran ring of the chromene unit adopts a half-chair conformation. An intra-molecular O-H⋯O hydrogen bond occurs. In the crystal, mol-ecules are linked along the b axis by C-H⋯O hydrogen bonds.

Journal: :Zeitschrift fur Naturforschung. C, Journal of biosciences 2002
Corinne Girard Michel Colombain Frédéric Muyard Françoise Bévalot François Tillequin Peter G Waterman

Phebarudol, a novel prenylated p-coumarate, was isolated from the twigs of Phebalium rude Bartl. subsp. amblycarpum (F. Muell.) P. G. Wilson (Rutaceae) together with the two already known related compounds, werneria chromene and methyl demethoxywutaiensate. The structure of phebarudol was established by spectroscopic methods.

Journal: :journal of chemical health risks 0
farhad hatamjafari department of chemistry, faculty of science, tonekabon branch, islamic azad university, tonekabon, iran

in this study, the synthesis of 4 h -chromenes of biological activity via a multicomponent reaction of dimedone, aromatic aldehydes and malononitrile catalyzed by glutamic acid as a catalyst was investigated. the structural features of the synthesized compounds were characterized by melting point, ir and 1 h nmr analysis. the catalyst being reported here is cheap, safe to handle and the whole p...

Journal: :iranian journal of catalysis 2013
mohammad vakili hossein eshghi maesam raeisian raheleh afzali ali reza berenji

two possible isomers of some 1,3-diaryl-h-benzo[f]chromene have been studied using density functional theory. structures of e1 and e2 isomers were optimized at the b3lyp and mp2 levels with different basis sets. the total electronic energies show that e2 isomer is about 3-5 kcal/mol more stable than e1 isomer and this energy difference is attributed to the planarity of heterocyclic ring and mor...

Journal: :Organic letters 2009
Fang-Jun Huo Yuan-Qiang Sun Jing Su Jian-Bin Chao Hai-Juan Zhi Cai-Xia Yin

A new thiol-containing colorimetric probe has been developed by using a chromene derivative, 7-nitro-2,3-dihydro-1H-cyclopenta[b]chromen-1-one (1). The molecule exhibited high selectivity and sensitivity for detecting thiol species as cysteine, homocysteine, and glutathione in aqueous solution through a rapid visual color change from colorless to yellow.

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