A series of 3,3-arylidene bis(4-hydroxycoumarins) were synthesized by the reaction of aromatic aldehydes with 4-hydroxycoumarin using dodecylbenzenesulfonic acid as Br?nsted acid-surfactant catalyst in aqueous media a...A series of 3,3-arylidene bis(4-hydroxycoumarins) were synthesized by the reaction of aromatic aldehydes with 4-hydroxycoumarin using dodecylbenzenesulfonic acid as Br?nsted acid-surfactant catalyst in aqueous media and under microwave irradiation. The present method is operationally simple and the use of water as the reaction medium makes the process environmentally benign.展开更多
α, α＇-Benzylidene bis（4-hydroxycoumarin） derivatives were readily prepared in a few minutes with good yields through the reaction of an aromatic aldehyde and 4-hydroxycoumarin in aqueous media in the presence of ...α, α＇-Benzylidene bis（4-hydroxycoumarin） derivatives were readily prepared in a few minutes with good yields through the reaction of an aromatic aldehyde and 4-hydroxycoumarin in aqueous media in the presence of catalytic tris（hydrogensulfato） boron [B（HSO_4）_3].展开更多
A series of novel 3-substituted-4-hydroxycoumarin derivatives 6（a-1） were synthesized in high yield using one-pot three component coupling reaction catalyzed by ceric ammonium nitrate. These compounds were evaluated...A series of novel 3-substituted-4-hydroxycoumarin derivatives 6（a-1） were synthesized in high yield using one-pot three component coupling reaction catalyzed by ceric ammonium nitrate. These compounds were evaluated for antileishmanial activity against Leishmania donovani promastigotes and antioxidant activity（DPPH-radical scavenging activity）. Two compounds, 6h（IC50= 9.90 μmol/L） and 6i（IC50= 6.90 μmol/L） displayed potent antileishmanial activity when compared with standard antileishmanial agents pentamidine（IC50= 16.15 μmol/L） and miltefosine（IC50= 12.50 μmol/L）. Three compounds, 6c（IC50= 10.79 μmol/L）, 6h（IC50= 10.60 μmol/L）, and 6i（IC50= 10.73 μmol/L） showed significant antioxidant activity favorably with the antioxidant standards butylated hydroxy toluene（IC50= 16.47 μmol/L） and ascorbic acid（IC50= 12.69 μmol/L）. A molecular docking study of compounds 6（a-1） suggested a possible mode of binding with the Adenine phosphoribosyltransferase enzyme of L.donovani. ADME properties were predicted in silico and support the potential of 6（a-1） to show favorable drug-like properties.展开更多
n-Dodecylbenzene sulfonic acid (DBSA) as a novel, biodegradable, and efficient Br?nsted acid catalyst used for the reaction of indoles/4-hydroxy coumarin with aldehydes to obtain a bis(indolyl)methanes/bis(4-hydroxyco...n-Dodecylbenzene sulfonic acid (DBSA) as a novel, biodegradable, and efficient Br?nsted acid catalyst used for the reaction of indoles/4-hydroxy coumarin with aldehydes to obtain a bis(indolyl)methanes/bis(4-hydroxycoumarin-3-yl)methanes, respectively. The catalyst exhibited remarkable activity, and tolerated a wide variety of functional groups providing the desired bis(indolyl)methanes and bis(4-hydroxycoumarin-3-yl)methanes in good to excellent yield (70%-96%) in water.展开更多
Sulfated tin oxide (STO) has been found to be an efficient reusable solid superacid catalyst for C3-alkylation and O-alkylation of 4-hydroxycoumarins with benzylic, allylic alcohols/and corresponding acetates respecti...Sulfated tin oxide (STO) has been found to be an efficient reusable solid superacid catalyst for C3-alkylation and O-alkylation of 4-hydroxycoumarins with benzylic, allylic alcohols/and corresponding acetates respectively, in acetic acid under reflux conditions with good yield of products.展开更多
文摘A series of 3,3-arylidene bis(4-hydroxycoumarins) were synthesized by the reaction of aromatic aldehydes with 4-hydroxycoumarin using dodecylbenzenesulfonic acid as Br?nsted acid-surfactant catalyst in aqueous media and under microwave irradiation. The present method is operationally simple and the use of water as the reaction medium makes the process environmentally benign.
文摘α, α＇-Benzylidene bis（4-hydroxycoumarin） derivatives were readily prepared in a few minutes with good yields through the reaction of an aromatic aldehyde and 4-hydroxycoumarin in aqueous media in the presence of catalytic tris（hydrogensulfato） boron [B（HSO_4）_3].
文摘A series of novel 3-substituted-4-hydroxycoumarin derivatives 6（a-1） were synthesized in high yield using one-pot three component coupling reaction catalyzed by ceric ammonium nitrate. These compounds were evaluated for antileishmanial activity against Leishmania donovani promastigotes and antioxidant activity（DPPH-radical scavenging activity）. Two compounds, 6h（IC50= 9.90 μmol/L） and 6i（IC50= 6.90 μmol/L） displayed potent antileishmanial activity when compared with standard antileishmanial agents pentamidine（IC50= 16.15 μmol/L） and miltefosine（IC50= 12.50 μmol/L）. Three compounds, 6c（IC50= 10.79 μmol/L）, 6h（IC50= 10.60 μmol/L）, and 6i（IC50= 10.73 μmol/L） showed significant antioxidant activity favorably with the antioxidant standards butylated hydroxy toluene（IC50= 16.47 μmol/L） and ascorbic acid（IC50= 12.69 μmol/L）. A molecular docking study of compounds 6（a-1） suggested a possible mode of binding with the Adenine phosphoribosyltransferase enzyme of L.donovani. ADME properties were predicted in silico and support the potential of 6（a-1） to show favorable drug-like properties.
文摘n-Dodecylbenzene sulfonic acid (DBSA) as a novel, biodegradable, and efficient Br?nsted acid catalyst used for the reaction of indoles/4-hydroxy coumarin with aldehydes to obtain a bis(indolyl)methanes/bis(4-hydroxycoumarin-3-yl)methanes, respectively. The catalyst exhibited remarkable activity, and tolerated a wide variety of functional groups providing the desired bis(indolyl)methanes and bis(4-hydroxycoumarin-3-yl)methanes in good to excellent yield (70%-96%) in water.
文摘Sulfated tin oxide (STO) has been found to be an efficient reusable solid superacid catalyst for C3-alkylation and O-alkylation of 4-hydroxycoumarins with benzylic, allylic alcohols/and corresponding acetates respectively, in acetic acid under reflux conditions with good yield of products.
