نتایج جستجو برای: 4h pyran

تعداد نتایج: 7801  

2013
Mohammad Ali Nasseri Seyed Mohsen Sadeghzadeh

ABSTRACT A magnetic nanoparticle supported hyperbranched polyglycerol catalyst was prepared readily from inexpensive starting materials in aqueous medium that catalyzed the synthesis of 4H-benzo[b]pyran under solvent-free conditions at room temperature. X-ray diffraction, transmission electron microscopy, thermal gravimetric analysis, vibrating sample magnetometry, and selected-area electron di...

2013
Ulrike Willeke Wolfgang Barz

Isoflavone, Biochanin A, Dihydrobiochanin A, Phenylacetic acids, Fusarium javanicum After a lag-phase of 1 h a mycelial suspension of Fusarium javanicum completely degraded 5,7-dihydroxy-4'-methoxyisoflavone (biochanin A) to a series of transiently accumulating catabolites. The compounds were elucidated by spectroscopic techniques and are arranged in the first known degradative pathway for an i...

2013
Shaaban K. Mohamed Mehmet Akkurt Antar A. Abdelhamid Aamer Saeed Ulrich Flörke

In the xanthene ring system in the title compound, C19H18O4, the 4H-pyran ring has a maximum deviation of 0.110 (2) Å from planarity and the cyclo-hexene ring exhibits a puckered conformation [puckering parameters Q T = 0.452 (3) Å, θ = 57.0 (4) and ϕ = 131.7 (4)°]. The cyclo-hexene ring attached to the xanthene system adopts an envelope conformation, with the middle of the three methylene C at...

2015
Mehmet Akkurt Peter N. Horton Sabry H. H. Younes Shaaban K. Mohamed Mustafa R. Albayati

In the title compound, C20H14N2O2, the hy-droxy-benzene ring is almost perpendicular to the mean plane of the naphthalene ring system, making a dihedral angle of 85.56 (4)°. The 4H-pyran ring fused with the naphthalene ring system has a flattened boat conformation. In the crystal, O-H⋯N and N-H⋯O hydrogen bonds link the mol-ecules into a supra-molecular layer in the bc plane; N-H⋯π inter-action...

2015
Mehmet Akkurt Peter N. Horton Shaaban K. Mohamed Sabry H. H. Younes Mustafa R. Albayati

In the title compound, C20H13ClN2O, the chloro-benzene ring is almost perpendicular to the mean plane of the naphthalene ring system, making a dihedral angle of 81.26 (8)°. The 4H-pyran ring fused with the naphthalene ring system has a flattened boat conformation. In the crystal, N-H⋯N hydrogen bonds generate chains along the b-axis direction. Further N-H⋯N hydrogen bonds link these chains into...

2014
Rui Gao Yixiu Cui Xiaojiang Liu Liduo Wang

In this paper, 4-(dicyanomethylene)-2-t-butyl-6(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) has been used in interface modification of dye-sensitized solar cells (DSCs) with combined effects of retarding charge recombination and Förster resonant energy transfer (FRET). DCJTB interface modification significantly improved photovoltaic performance of DSCs. I-V curves shows the conversion...

2015
Shaaban K. Mohamed Peter N. Horton Mehmet Akkurt Sabry H. H. Younes Mustafa R. Albayati

In the title compound, C20H14N2O, the plane of the phenyl ring is almost normal to that of the naphthalene ring system, forming a dihedral angle of 83.15 (8)°. The 4H-pyran ring fused with the naphthalene ring system has a flattened boat conformation. In the crystal, mol-ecules are linked by pairs of N-H⋯N hydrogen bonds, forming inversion dimers with an R 2 (2)(12) ring motif. The dimers are c...

The three components one pot synthesis of 2-amino-4H-benzo-[b] -pyran derivatives were obtained in good to excellent yields within short reaction time by condensing dimedone, aldehydes and malanonitrile or ethylcyanoacetate using a catalytic amount of (diacetoxyiodo)benzene as hypervalent iodine in aqueous ethanol under reflux conditions have been discussed. This aqua mediated Knoevenagel-cyclo...

Journal: :Chemical Bulletin of Kazakh National University 2018

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