Synthesis of 4-hydroxycoumarin and 2,4-quinolinediol derivatives and evaluation of their effects on the viability of HepG2 cells and human hepatocytes culture

Reaction of Coumarin Derivatives with Nucleophiles in Aqueous Medium

“…The use of base required in such reactions was obviated by performing the reaction in water which not only avoided the use of base but also gave good yields (75 -90 %) within 4.0 -6.0 minutes of microwave irradiation (MWI). Products 3a-d were easily isolated from the reaction medium Scheme 1. as they precipitated as insoluble solids from water, and the structures of the known α,β -unsaturated carbonyl compounds were found to be in consistency with the spectroscopic data [24]. The reaction conditions of the second step (Scheme 1) were optimized for the cyclocondensation of 3a-d with the nitrogen containing nucleophiles (NH 2 -G) hydroxylamine hydrochloride, hydrazine, urea and thiourea to afford 3-(substituted aryl)-3,3a-dihydrochromeno [4,3- Different solvents such as ethanol, water or benzene with different combinations of temperature and reaction time were studied in order to achieve atom economy within shorter reaction time.…”

Synthesis and DFT study of the spectral behavior of new 4‐hydroxycoumarins

“…5). The newly synthesized compounds were characterized by IR, UV-vis, 1 H NMR, and mass-spectrometry, elemental analysis.…”

“…It was reported that 4-methoxycoumarin had specific vibration for ester carbonyl group at 1,710 cm Ϫ1 compared to its tautomeric form 2-methoxychromone, which had the same vibration at 1,635 cm Ϫ1 . 1 H NMR study of dicoumarol showed that there was a specific intramolecular hydrogen bond between 4-hydroxyl and lactone carbonyl group.…”

“…One group of differently 3-substituted benzylydenecoumarins was obtained after Knoevenagel condensation of 4-hydroxycoumarin and substituted aromatic aldehydes [1]. The reaction was carried out in pyridine in only one diastereomeric (Z-) form was obtained.…”

Synthesis of 5-Oxycoumarin and Fused Coumarin Derivatives and Evaluation of Their Antitumor Activity.

“…This addition was accompanied by the elimination of one molecule of water and conducted to a non-isolable enaminone intermediate [16]. Subject to a nucleophilic attack at the 6-position of the coumarin, the bis(o-aminophenyl) disulfide motif was cleaved and the enaminone led to the desired product 8 by an interamolecularcyclization.…”