2-Dimethyl-2H-Chromenes, Coumarin Derivatives, Phase-Transfer Catalysis 2,2-Dimethyl-5H-pyrano(3,2-c)-l-benzopyrano-5-one(2) and 4H-2,3-dihydro-3-methyl-2methylene-furan-l-benzopyran-4-one (3), two new coumarin derivatives were synthesised from 4-hydroxycoumarin by treating with 3-chloro-3-methylbut-l-yne and 3-chlorobut-l-yne respectively, both reactions progressing via the phase-transfer cata...

In the title compound, C20H14O4, the dihedral angle between the two coumarin ring systems is 52.37 (19)°, showing a gauche arrangement across the C-C bond which links the two units. The carbonyl groups of the two coumarin units adopt an s-trans arrangement. In the crystal, pairs of C-H⋯O hydrogen bonds and π-π inter-actions [centroid-centroid distance = 3.631 (2) Å] connect the mol-ecules into ...

In the title compound, C17H12O5, the dihedral angle between the planes of the coumarin ring system (r.m.s. deviation = 0.015 Å) and the benzene ring is 48.04 (10)°. The central CO2 group subtends a dihedral angle of 27.15 (11)° with the coumarin ring system and 74.86 (13)° with the benzene ring. In the crystal, mol-ecules are linked by C-H⋯O inter-actions, which generate a three-dimensional net...

7-hydroxy coumarin undergoes neutral conditions with alkyl propiolates in the presence of triphenylphosphine, and bysubstituation the corresponding aryl vinyl ethers was obtained in good yields

In this study, a series of coumarin chromophore-based oxime-esters were designed and synthesized as visible light photoinitiators (PIs).

CYP2A6, a member of the cytochrome P450 (P450) family, is one of the enzymes responsible for the metabolism of therapeutic drugs and such tobacco components as nicotine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, and N-nitrosodiethylamine. Genetic polymorphisms in CYP2A6 are associated with individual variation in smoking behavior, drug toxicities, and the risk of developing several cancer...

The ability to create aqueous suspended stable nanoparticles of the hydrophobic homopolymer poly(ϵ-caprolactone) end-functionalized with coumarin moieties (CPCL) is demonstrated. Nanoparticles of CPCL are prepared in a continuous manner using nanoprecipitation. The resulting nanoparticles are spherical in morphology, about 40 nm in diameter, and possess a narrow size distribution and excellent ...

In this work, nanostructured CdO films with different coumarin contents in the growth solution were fabricated on glass substrates by the SILAR method. The effects of coumarin content in the bath on optical, structural and morphological properties were studied by means of (UV–vis) spectrophotometer, SEM and XRD analysis. The analysis showed that the band gaps, surface morphologies and XRD peak ...

The title compound, a bis-5,5'-triazole, C(38)H(28)N(6)O(4), was observed as a side-product from the Sharpless-Meldal click reaction of the corresponding coumarin alkyne and benzyl-azide. Although the compound was present as a minor component, it crystallized in preference to the major product. The two triazole rings are almost orthogonal to each other [dihedral angle = 83.8 (1)°]. However the ...

In the title mol-ecule, C(24)H(22)O(8), the mean planes of the two coumarin units are inclined to each other at a dihedral angle of 79.93 (3)°. The attached meth-oxy groups form torsion angles of 7.65 (19) and 78.36 (14)° with respect to one coumarin unit, and angles of 9.01 (16) and 99.08 (11)° with respect to the other coumarin unit. In the crystal structure, weak inter-molecular C-H⋯O hydrog...