Synthesis, spectral analysis and bioactivity of new coumarin derivatives are described in this paper. Eight new coumarin derivatives were synthesized in moderate to good yields by condensation of 4-chloro-3-nitrocoumarin and the corresponding heteroarylamine. The synthesized compounds were tested for their in vitro antimicrobial activity, in a standard disk diffusion assay, against thirteen str...

The mass spectrometry of a number of 6-substituted coumarins was studied in the context of correlating fragmentation pathways and electronic charges of atoms performed by AM1 semiempirical method. The atomic charges of atoms are found to be good predictors of the fragmentation pathways.

nano sulfated titania was tested as solid acid heterogeneous catalyst for the synthesis of 4-(trifluoromethyl) coumarin and coumarin derivatives under solvent-free condition. factorial design evidenced a positive effect of reaction temperature, amount of catalyst, and solvents.  this nano-sized sulfated titania has been prepared by a sol-gel hydrothermal process. the prepared sulfated titania s...

Coumarin belongs to the family of benzopyrone found to have lot of biologically important. The present investigation focused on the synthesis of four derivatives from 4-Hydroxy-chromen-2-one and characterized using spectral (FTIR, H and C-NMR), Thermal (TGA) and morphological studies (SEM).

The microbial transformation of coumarin (1) and 6-methyl coumarin (2) using Colletotrichum capsici gave 2-(3'-hydroxypropyl) phenol (3) and 2-(3'-hydroxypropyl)-4-methyl phenol (4). The phytopathogenic fungi effectively reduced the 2H-pyran-2-one moiety of both parent coumarins to respective alcohols.

The cytotoxicity of 22 natural and semi-synthetic simple coumarins was evaluated in GLC4, a human small cell lung carcinoma cell line, and in COLO 320, a human colorectal cancer cell line, using the microculture tetrazolium (MTT) assay. With IC50 values > 100 microM, following a continuous (96 h) incubation, most coumarins exhibited only low cytotoxicity. Several compounds, however, displayed s...

In this article we describe a new methodology for the total synthesis of 3,4-unsubstituted coumarins from commercially available starting materials. Six examples were prepared, including five naturally occurring coumarins--7-hydroxy-6,8-dimethoxy-coumarin (isofraxidin), 7-hydroxy-6-methoxycoumarin (scopoletin), 6,7,8-trimethoxy-coumarin, 6,7-dimethoxycoumarin (scoparone), and 7,8-dihydroxycouma...

A new regioselective α-arylation of coumarins with unactivated simple arenes via a palladium-catalyzed twofold C-H functionalization is devised. This method offers an attractive new approach to synthesis of a wide variety of 3-arylcoumarins from readily accessible starting materials.

A mild and efficient method has been developed for the preparation of substituted coumarins from reaction of various phenols with different β-ketoesters via Pechmann condensation in the presence of Brønsted acidic ionic liquid (N-(4-sulfonic acid) butyl triethylammonium hydrogen sulfate) as an effective catalyst under solvent-free conditions. Different phenols reacted with ethyl acetoacetate to...