نتایج جستجو برای: pyran derivatives
تعداد نتایج: 106108 فیلتر نتایج به سال:
In the title mol-ecule, C11H10ClFO2, the benzene ring, the F atom and the O atom of the di-hydro-pyran ring are essentially coplanar, with an r.m.s. deviation of 0.007 Å. The di-hydro-pyran ring is in a half-chair conformation. In the crystal, mol-ecules are linked by pairs of weak C-H⋯π hydrogen bonds, forming inversion dimers.
A new method for the synthesis of pyran fused coumarins by 3-bromo-4-hydroxycoumarins as cyclic α-halo ketones based on an organocatalyst assisted three-component tandem reaction is investigated. To the best of our knowledge, cyclic α-halo ketones have not yet been used for the synthesis of pyran fused coumarins.
In the title compound, C(23)H(25)NO(5), the pyran ring adopts a flattened boat conformation, while the two cyclo-hexenone rings are in envelope conformations. The 3-nitro-phenyl ring is almost perpendicular to the pyran ring, making a dihedral angle of 87.1 (3)°.
Electrochemical synthesis suggested a mild, green and atom-efficient route to interesting useful molecules, thus avoiding harsh chemical oxidizing reducing agents used in traditional synthetic methods. Organic electrochemistry offers an excellent alternative conventional methods of organic creates modern tool for carrying out synthesis, including cascade multicomponent ones. In this research, n...
Transient precursor states are often experimentally observed for molecules adsorbing on surfaces. However, such precursor states are typically rather short-lived, quickly yielding to more stable adsorption configurations. Here we employ first-principles calculations to systematically explore the interaction mechanism for benzene derivatives on metal surfaces, enabling us to selectively tune the...
The title compound, C(24)H(29)NO(7), is asymmetric with a chiral centre located in the pyran ring and crystallizes as a racemate. The coumarin ring system and the fused pyran ring make a dihedral angle of 10.46 (8)°. A short intra-molecular N-H⋯O hydrogen bond between the amino group and the vicinal carbonyl group generates an S(6) ring. Inter-molecular C-H⋯O inter-actions contribute to the sta...
In the title compound, C(21)H(22)O(5), the mean planes of the pyran and dimeth-oxy-phenyl rings are nearly perpendicular to one another, with the dihedral angle between them being 88.21 (8)°. The pyran ring adopts a boat conformation whereas the two fused cyclo-hexane rings adopt envelope conformations. In the crystal, mol-ecules are linked into a three-dimensional network by inter-molecular C-...
The title compound, C23H20N2O6, crystallizes with two mol-ecules in the asymmetric unit in which the dihedral angles between the mean planes of the pyran and phenyl rings are 66.6 (1) and 61.9 (1) °. The fused pyrone and pyran rings each adopts a sofa conformation. In the crystal, C-H⋯O hydrogen bonds link the mol-ecules, forming a two-dimensional network parallel to [001].
The title compound, C(21)H(21)ClO(7)·C(2)H(5)OH was synthesized by the condensation reaction between helicid [systematic name: 4-(β-d-allopyranos-yloxy)benzaldehyde] and 4-chloro-aceto-phen-one in ethanol. In the mol-ecular structure, the pyran-oside ring adopts a chair conformation. In the crystal structure, the molecules are linked by inter-molecular O-H⋯O hydrogen bonds involving the OH grou...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید