A four-step synthesis of allylic trichloroacetimidates bearing a 2-proparyloxyaryl group has been developed from readily available 2-hydroxybenzaldehydes, and these have been used for the preparation of allylic amide derived 2H-chromenes using an Overman rearrangement and a 6-endo-dig hydroarylation. High yields of the 2H-chromenes were achieved using a stepwise approach involving an Overman re...

Conditions enabling the single-step preparative synthesis of chiral 4-fluoropolyhydro-2H-chromenes in good yields through a reaction between monoterpenoid alcohols with para-menthane skeleton and aldehydes were developed for the first time. The BF3·Et2O/H2O system is used both as a catalyst and as a fluorine source. The reaction can involve aliphatic aldehydes as well as aromatic aldehydes cont...

(7-Hydroxy-2-oxo-2H-chromen-4-yl)-acetic acid hydrazide (2) was prepared from (7-hydroxy-2-oxo-2H-chromen-4-yl)-acetic acid ethyl ester (1) and 100% hydrazine hydrate. Compound 2, is the key intermediate for the synthesis of several series of new compounds such as Schiff's bases 3a-l, formic acid N'-[2-(7-hydroxy-2-oxo-2H- chromen-4-yl)acetyl] hydrazide (4), acetic acid N'-[2-(7-hydroxy-2-oxo-2...

Starting from 2-imino-N-phenyl-2H-chromene-3-carbox-amide, (1) a series of functionalized chromenes were achieved; such as, 2-ethoxy-2,3-dihydro-3-phenylchromeno[2,3-d]pyrimidin-4-one (2), and 2-hydrazinyl-2,3-dihydro-3-phenylchromeno-[2,3-d]pyrimidin-4-one (3). Furthermore, reactions of (3) with some of laboratory available compounds gave pyrazoles (4 9, 12, 13a, 13b), tetrazoles (11), 2-(2-be...

Gold nanoparticles supported on TiO(2) (~1%) catalyse in high yields the selective cycloisomerisation of aryl propargyl ethers into the corresponding 2H-chromenes, under heterogeneous conditions. 2H,2'H-3,3'-Bichromenes resulting from a catalytic oxidative dimerization pathway are also formed as by-products.

An enantioselective Pd-catalyzed 6-endo-trig reaction for the synthesis of 2-aryl-chromenes has been developed. A systematic optimization of a TADDOL-derived ligand set resulted in the identification of a novel monodentate phosphoramidite-palladium catalyst that accesses 2-aryl-2H-chromenes with high yield and enantioselectivity under mild conditions. The products obtained from this method can ...

Bismuth triflate (Bi(OTf)3) is identified as an efficient catalyst for the direct addition of isocyanides to 2H-chromene acetals. The large scope of isocyanides and chromene acetals makes them suitable substrates in this catalytic system. By this synthetic strategy, a polyfunctional molecular scaffold, 2-carboxamide-2H-chromenes could be prepared efficiently in one step up to 95% yield. In addi...

A series of 3-substituted-2-thioxoquinazolin-4(3H)-one derivatives have been synthesized and their structures have been elucidated on the basis of IR, (1)H-NMR, elemental analysis and mass spectroscopic studies. Anti-inflammatory and analgesic activity of the synthesized compounds was evaluated by Carrageenan induced rat paw edema method and Eddy's hot plate method respectively. Among the synth...

New coumarin derivatives, namely (2-(4-methyl-2-oxo-2H-chromen-7-yloxy)-N-(4-oxo-2-phenylthiazolidin-3-yl)acetamide, N-(2-(3-methoxyphenyl)-4-oxothiazolidin-3-yl)-2-(4-methyl-2-oxo-2H-chromen-7-yloxy)acetamide, 2-(4-methyl-2-oxo-2H-chromen-7-yloxy)-N-(4-oxo-2-(2,3,4trimethoxyphenyl)thiazolidin-3-yl)acetamide and N-(2-(4-bromophenyl)-4-oxothiazolidin-3-yl)-2-(4-methyl-2-oxo-2H-chromen-7-yloxy)ac...

BACKGROUND Coumarin and their derivatives are important and useful compounds with diverse pharmacological properties. In the present study, we evaluated the in vitro cytotoxic activity of new acetoxycoumarin derivatives: 4-(7-methoxy-4-methyl-2-oxo-2H-chromen-3-yl)phenyl acetate (1), 4-(1-methyl-3-oxo-3H-benzo[f]chromen-2-yl)phenyl acetate (2), 4-(6-propionamido-4-methyl-2-oxo-2H-chromen-3-yl) ...