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
3-（4-Hydroxyphenyl）-4-methyl-6-methoxy-7-hydroxycoumarin （2a） and its analogues with different substituents at the p-position of 3-phenyl group were designed and synthesized as the non-steroidal analogues of 2-met...3-（4-Hydroxyphenyl）-4-methyl-6-methoxy-7-hydroxycoumarin （2a） and its analogues with different substituents at the p-position of 3-phenyl group were designed and synthesized as the non-steroidal analogues of 2-methoxyestradiol （2-ME 1）. The desired compounds were synthesized via a novel and simple route and the effects of specific substituents on their antiangiogenesis activities were investigated with Human umbilical vein endothelial cells （HUVECs） proliferation assays. Preliminary biological screening showed that compounds 2a and 2d （IC50 = 61.0 and 76.7 ktM, respectively） have potential anti-angiogenesis activities. The bulk of the group at the p-position of 3-phenyl group likely play an important role in their activities.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
A novel one-pot synthesis of furo[3,2-c]coumarins has been developed from readily available starting materials 4-hydroxycoumarin and arylglyoxal. This method is simple, rapid and good yielding.
A new enantioselective aldol-type reaction of 4-hydroxycoumarins and ethyl trifluoropyruvate has been developed. In the presence of (DHQD)2PHAL (5 mol%), ethyl trifluoropyruvate could react with various 4-hydroxycouma...A new enantioselective aldol-type reaction of 4-hydroxycoumarins and ethyl trifluoropyruvate has been developed. In the presence of (DHQD)2PHAL (5 mol%), ethyl trifluoropyruvate could react with various 4-hydroxycoumarins to afford novel 4-hydroxycoumarin derivatives containing a tertiary trifluoromethyl alcohol center in good yields with moderate enantioselectivities.展开更多
The condensation reaction of 4-hydroxycoumarin with each of ah substituted benzalacetones in（absolute） ethanol gave coumarin analogues which were subsequently converted to their ethyl ethers（cyclocou-（marin））.Th...The condensation reaction of 4-hydroxycoumarin with each of ah substituted benzalacetones in（absolute） ethanol gave coumarin analogues which were subsequently converted to their ethyl ethers（cyclocou-（marin））.The ethers can be quantitatively converted back to the coumarin analogues by acid hydrolysis.Four of them are new substances.The reaction mechanism is discussed in detail.All the products were characterized by HPLC,IR and 1H NMR.Compared with the present process in the literature,the process for the synthesis of the coumarin analogues is obviously improved on the reaction time,temperature,solvent,（catalyst）,and post-treatment.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3-（4-Hydroxyphenyl）-4-methyl-6-methoxy-7-hydroxycoumarin （2a） and its analogues with different substituents at the p-position of 3-phenyl group were designed and synthesized as the non-steroidal analogues of 2-methoxyestradiol （2-ME 1）. The desired compounds were synthesized via a novel and simple route and the effects of specific substituents on their antiangiogenesis activities were investigated with Human umbilical vein endothelial cells （HUVECs） proliferation assays. Preliminary biological screening showed that compounds 2a and 2d （IC50 = 61.0 and 76.7 ktM, respectively） have potential anti-angiogenesis activities. The bulk of the group at the p-position of 3-phenyl group likely play an important role in their activities.
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A novel one-pot synthesis of furo[3,2-c]coumarins has been developed from readily available starting materials 4-hydroxycoumarin and arylglyoxal. This method is simple, rapid and good yielding.
基金supported by Sichuan Provincial Government (07ZQ026027)
文摘A new enantioselective aldol-type reaction of 4-hydroxycoumarins and ethyl trifluoropyruvate has been developed. In the presence of (DHQD)2PHAL (5 mol%), ethyl trifluoropyruvate could react with various 4-hydroxycoumarins to afford novel 4-hydroxycoumarin derivatives containing a tertiary trifluoromethyl alcohol center in good yields with moderate enantioselectivities.
文摘The condensation reaction of 4-hydroxycoumarin with each of ah substituted benzalacetones in（absolute） ethanol gave coumarin analogues which were subsequently converted to their ethyl ethers（cyclocou-（marin））.The ethers can be quantitatively converted back to the coumarin analogues by acid hydrolysis.Four of them are new substances.The reaction mechanism is discussed in detail.All the products were characterized by HPLC,IR and 1H NMR.Compared with the present process in the literature,the process for the synthesis of the coumarin analogues is obviously improved on the reaction time,temperature,solvent,（catalyst）,and post-treatment.
