Synthesis, structure, toxicological and pharmacological investigations of 4-hydroxycoumarin derivatives

A Rapid, Efficient and Green Method for Synthesis of 3,3'-Arylmethylene-bis-4-hydroxycoumarins without Use of any Solvent, Catalyst or Solid Surface

“…3,3'-Arylmethylene-bis-4-hydroxycoumarins (3), commonly known as biscoumarins, are the bridge substituted dimers of 4-hydroxycoumarin. They have enormous potential as anticoagulants 1,8,9 and antioxidants 6 and some of them have also been found to be urease inhibitors 10 . The compound 3,3 ′ -methylene-bis-4-hydroxycoumarin, commonly known as dicoumarol, occurs naturally in moldy clover 11 .…”

“…It is the hemorrhagic agent responsible for the sweet clover disease of cattle and has also been employed for the prevention and treatment of thrombosis 12 . 3,3'-Arylmethylene-bis-4-hydroxycoumarins (3) are usually synthesized by condensing 4-hydroxycoumarin (1) with various aldehydes (aromatic, heterocyclic and α,β-unsaturated) (2) using different catalysts and media [8][9][10][13][14][15][16][17][18][19] . Some of these methods require long reaction time, use of expensive catalysts and organic solvents and tedious work up 8,10 .…”

A Convenient, Eco-friendly, and Efficient Method for Synthesis of 3,3'-Arylmethylene-bis-4-hydroxycoumarins "On-water"

“…They are also used as agrochemicals 11 and analytical reagents. 12 Biscoumarins (3), the bridge substituted dimers of 4-hydroxycoumarin, have enormous potential as anticoagulants 6,13,14 and antioxidants 11 and some of them have also been found to be urease inhibitors. 15 It may be mentioned here that 3,3'-methylenebis-4-hydroxycoumarin, commonly known as dicoumarol, occurs naturally in moldy clover.…”

“…16 3,3'-Arylmethylene-bis-4-hydroxycoumarins (3), commonly known as biscoumarins, are usually synthesized by condensing 4-hydroxycoumarin (1) with various aldehydes (aromatic, heterocyclic, and α,β-unsaturated) 2 using different catalysts and media. [13][14][15][17][18][19][20][21][22][23][24] Some of these methods require long reaction time, use of expensive catalysts and organic solvents and tedious work up. 13,15,24 In four recent papers, the said condensation has been reported to be performed in water by employing molecular iodine, 17 ruthenium(III) chloride hydrate 24 or surfactants like TBAB 18 or DDS 19 as catalyst.…”

An efficient synthesis of some new isolated and fused 2-oxo-2H-chromene derivatives as antimicrobial and antitumor agents

“…Fused and isolated 2-oxo-2H-chromenes (coumarins) comprise a very interesting class of compounds due to their significant antibacterial [1], antifungal [2][3][4], antimycobecterial [5,6], anticoagulants [7,8], inhibition of some enzymes [9,10] and antitumor [11][12][13] activities. With the expectations to find biological activity, we decided to investigate the synthesis of some novel systems of 2-oxo-2H-chromene derivatives bearing fused and isolated moieties.…”