نتایج جستجو برای: pyran annulated hetrocyclic systems
تعداد نتایج: 1185076 فیلتر نتایج به سال:
The rearrangement under oxidative conditions of 3-(benzyloxy)-tetrahydro- 2,6,6-trimethyl-2H-pyran-2-carbaldehydes to afford a chiral protected tetrahydrofuran lactol is described.
Transition metal complexes containing bidentate O,O donor ligand, i.e. 3-[3-(4-chlorophenyl)4-hydroxy-6-methyl-pyran 2-one derived from 3-acetyl-6-methyl-pyran-2,4(3H)-dione (dehydroacetic acid) and p-chlorobenzaldehyde,have been synthesized and characterized by elemental analyses, conductometry, thermal analysis, magnetic,IR, UV-Vis and fungicidal study. From the analytical and thermal data, t...
In the title compound, C25H27FO3, each of the cyclo-hexenone rings adopts a half-chair conformation, whereas the six-membered pyran ring adopts a flattened boat conformation, with the O and methine C atoms deviating by 0.0769 (15) and 0.196 (2) Å, respectively, from the plane of the other four atoms (r.m.s. deviation = 0.004 Å). The C=C double bond adopts an E conformation. The dihedral angle b...
In the title compound, C30H29BrN2O5, the β-lactam ring is essentially planar, with the O atom displaced from this plane by 0.856 (9) Å, and forming dihedral angles of 24.35 (13) and 89.42 (14)° with the planes of the benzene substituent groups on this ring. The tetra-hydro-pyran ring adopts an envelope conformation with the C atom bearing the β-lactam ring as the flap. In the crystal, weak C-H⋯...
In the title compound, C(16)H(16)ClNO(2)S(2), the piperidine ring is in a chair conformation. In the coumarin ring system, the dihedral angle between the benzene and pyran rings is 3.5 (1)°. In the crystal, a weak C-H⋯O hydrogen bond links mol-ecules into chains along [001]. In addition, π-π stacking inter-actions are present involving the benzene and pyran rings, with a centroid-to-centroid di...
In the title compound, C11H8O3, the fused-ring system is almost planar (r.m.s. deviation = 0.020 Å), with the largest deviation from the least-squares plane [0.0462 (17) Å] being for a pyran C atom. The dihedral angle between the plane of the fused-ring system and acetyl plane is 5.149 (16)°. In the crystal, the fused rings are linked by aromatic π-π stacking inter-actions [centroid-centroid di...
The structure of a representative pyrazolo[3,4]pyran derivative was determined by 1D and 2D NMR techniques. Complete 1H and 13C chemical shifts for this compound are reported. Careful analysis of the HMBC (Heteronuclear Multi-Bond Correlation) spectrum helped to elucidate the configuration of the derivative around C7 and C8. The results showed that the characteristic double-strong and double-we...
The multistep synthesis of the N-annulated rylenecarbodiimide 1 is reported. large π-surface and operation a fourfold array H-bonding interactions between trialkoxybenzamide units yield highly stable supramolecular polymers, stability which has been quantified by applying denaturation model. these non-covalent affords long 1D-supramolecular polymers that have visualized atomic force microscopy ...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید