A new and convenient visible-light-induced method has been developed for the synthesis of sulfonylated benzofurans via oxidative cyclization reaction of 1,6-enynes and arylsulfinic acids.This reaction was carried out ...A new and convenient visible-light-induced method has been developed for the synthesis of sulfonylated benzofurans via oxidative cyclization reaction of 1,6-enynes and arylsulfinic acids.This reaction was carried out under metal-free and mild conditions,in which the C-S,C-C and C=O bonds could be sequentially formed in one pot operation.展开更多
A catalytic asymmetric brominative dearomatization reaction of benzofuran derivatives was achieved by using hydroquinidine 1,4-phthalazinediyl diether [（DHQ）_2PHAL] as the catalyst and N-bromoacetamide（NBAc） as th...A catalytic asymmetric brominative dearomatization reaction of benzofuran derivatives was achieved by using hydroquinidine 1,4-phthalazinediyl diether [（DHQ）_2PHAL] as the catalyst and N-bromoacetamide（NBAc） as the brominating reagent. A series of brominated spiro[benzofuran-2,5＇-oxazoles] bearing two contiguous stereogenic centers were obtained in high yields（up to 99%） with excellent enantioselectivity（up to 97% ee）.展开更多
Herein,the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO)complex catalyze asymmetric formal[3+2]cycloaddition between quinones and ynamides is explored,producing ...Herein,the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO)complex catalyze asymmetric formal[3+2]cycloaddition between quinones and ynamides is explored,producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities.Furthermore,density functional theory calculations were applied to explain the possible reaction mechanism.展开更多
Chemodivergent synthesis of benzofurans and 2,3-dihydrobenzofurans has been realized.Under a reaction system consisting of DBDMH and K_(2)CO_(3) as promotors,controlled conditions enabled the formation of two sets of ...Chemodivergent synthesis of benzofurans and 2,3-dihydrobenzofurans has been realized.Under a reaction system consisting of DBDMH and K_(2)CO_(3) as promotors,controlled conditions enabled the formation of two sets of valuable heterocycles from the tandem transformation of enaminones and salicylaldehydes.The key to success was the identification of the reaction parameters,in which the imine intermediate which was formed by transient halogenation coupling and substitution processes underwent either aldol condensation/annulation or imine hydrolysis/aldol condensation.The additives NH_(4)Cl or Fe_(2)(SO_(4))_(3) controlled the unique selectivity of this reaction.A broad substrate scope of enaminones and salicylaldehydes has been employed in this reaction,demonstrating excellent functional group tolerance and versatility.展开更多
A one-pot three-component method for the synthesis of 2-methyl-3-aminobenzofurans using calcium carbide as a concise solid alkyne source,and salicylaldehydes and secondary amines as starting materials is described.Thi...A one-pot three-component method for the synthesis of 2-methyl-3-aminobenzofurans using calcium carbide as a concise solid alkyne source,and salicylaldehydes and secondary amines as starting materials is described.This protocol has salient feature of the use of inexpensive,abundant and easy-to-handle alkyne source,avoiding the use of inflammable and explosive acetylene gas as an original alkyne source.In addition,step economy,satisfactory yield,and simple work-up procedure are also advantages of this route.展开更多
In this paper,we developed an electrophilic ring-opening reaction,which is beyond the strained small ring system.Under reductive nickel catalysis,ring-opening of diverse benzofurans via endocyclic inert carbon–oxygen...In this paper,we developed an electrophilic ring-opening reaction,which is beyond the strained small ring system.Under reductive nickel catalysis,ring-opening of diverse benzofurans via endocyclic inert carbon–oxygen bond cleavage can be achieved with an array of inactivated secondary and tertiary alkyl halides as coupling partners,allowing for the preparation of a series of(E)-o-alkenylphenols with excellent E/Z-selectivity and high functional tolerance.The utility of this method was further demonstrated through derivatizations of the ring-opening products using the o-hydroxyl group as a functional handle,providing various organic compounds in good to high efficiency.展开更多
Benzofuran is an essential structural component found in a wide range of natural products,agrochemicals and drugs,possessing a range of biological activities.In recent years,there have been numerous reports of success...Benzofuran is an essential structural component found in a wide range of natural products,agrochemicals and drugs,possessing a range of biological activities.In recent years,there have been numerous reports of successful syntheses of benzofuran derivatives via intra-and inter-molecular cyclizations using diverse catalysts.This review gives an exhaustive and methodical survey of the procedures for making benzofurans.展开更多
Flavonoids are by far the most dominant class of phenolic compounds isolated from Morus alba leaves(MAL). Other classes of compounds are benzofurans, phenolic acids, alkaloids, coumarins, chalcones and stilbenes. Majo...Flavonoids are by far the most dominant class of phenolic compounds isolated from Morus alba leaves(MAL). Other classes of compounds are benzofurans, phenolic acids, alkaloids, coumarins, chalcones and stilbenes. Major flavonoids are kuwanons, moracinflavans, moragrols and morkotins. Other major compounds include moracins(benzofurans), caffeoylquinic acids(phenolic acids) and morachalcones(chalcones). Research on the anticancer properties of MAL entailed in vitro and in vivo cytotoxicity of extracts or isolated compounds. Flavonoids, benzofurans, chalcones and alkaloids are classes of compounds from MAL that have been found to be cytotoxic towards human cancer cell lines. Further studies on the phytochemistry and anticancer of MAL are suggested. Sources of information were Pub Med,Pub Med Central, Science Direct, Google, Google Scholar, J-Stage, Pub Chem and China National Knowledge Infrastructure.展开更多
The root bark of Morus alba L. or white mulberry is widely used as traditional medicine in China, Japan and Korea. Major classes and types of phenolic compounds isolated from the root bark are flavonoids(kuwanons, mor...The root bark of Morus alba L. or white mulberry is widely used as traditional medicine in China, Japan and Korea. Major classes and types of phenolic compounds isolated from the root bark are flavonoids(kuwanons, morusin, cyclomorusin and sanggenons), benzofurans(moracins and mulberrofurans), and stilbenoids(mulberrosides). Some of the flavonoids and benzofurans are products of Diel-Alder type adducts. Other classes of compounds include triterpenes, phenolic acids and coumarins. Morusin, a prenylated flavonoid, was first isolated from the root bark of M. alba, and later from the leaf, stem bark and twig of the plant. The potent anti-cancer properties of morusin have attracted much attention with research on-going and new findings being published. The compound inhibits angiogenesis, tumour progression and tumour migration, and triggers apoptosis, cell cycle arrest and autophagy in colorectal, cervical, prostate, breast, hepatoma, pancreatic, glioblastoma, gastric, ovarian and lung cancer cell lines. The anti-cancer activities of morusin are executed via various molecular targets and signalling pathways. It is anticipated that on-going in vitro studies will progress gradually to in vivo studies using animal models before efforts towards drug development can be initiated for clinical trials.展开更多
AIM:To investigate the pathway(s)mediating rat antral circular smooth muscle contractile responses to the cholinomimetic agent,bethanechol and the subtypes of muscarinic receptors mediating the cholinergic contraction...AIM:To investigate the pathway(s)mediating rat antral circular smooth muscle contractile responses to the cholinomimetic agent,bethanechol and the subtypes of muscarinic receptors mediating the cholinergic contraction. METHODS:Circular smooth muscle strips from the antrum of Sprague-Dawley rats were mounted in muscle baths in Krebs buffer.Isometric tension was recorded.Cumulative concentration-response curves were obtained for(+)-cis- dioxolane(cD),a nonspecific muscarinic agonist,at 10^(-8)- 10^(-4)mol/L,in the presence of tetrodotoxin(TTX,10^(-7)mol/L). Results were normalized to cross sectional area.A repeat concentration-response curve was obtained after incubation of the muscle for 90 min with antagonists for M1(pirenzepine), M2(methoctramine)and M3(darifenadn)muscarinic receptor subtypes.The sensitivity to PTX was tested by the ip injection of 100 mg/kg of PTX 5 d before the experiment.The antral circular smooth muscles were removed from PTX-treated and non-treated rats as strips and dispersed smooth muscle cells to identify whether PTX-linked pathway mediated the contractility to bethanechol. RESULTS:A dose-dependent contractile response observed with bethanechol,was not affected by TTx.The pretreatment of rats with pertussis toxin decreased the contraction induced by bethanechol.Lack of calcium as well as the presence of the L-type calcium channel blocker,nifedipine,also inhibited the cholinergic contraction,with a reduction in response from 2.5±0.4 g/mm^2 to 1.2±0.4 g/mm^2(P<0.05).The dose- response curves were shifted to the right by muscarinic antagonists in the following order of affinity:darifenacin (M_3)>methocramine(M_2)>pirenzepine(M_1). CONCLUSION:The muscarinic receptors-dependent contraction of rat antral circular smooth muscles was linked to the signal transduction pathway(s)involving pertussis-toxin sensitive GTP-binding proteins and to extracellular calcium via L-type voltage gated calcium channels.The presence of the residual contractile response after the treatment with nifedipine,suggests that an additional pathway could mediate the cholinergic contraction.The involvement of more than one muscarinic receptor(functionally predominant type 3 over type 2)also suggests more than one pathway mediating the cholinergic contraction in rat antrum.展开更多
The deconstructive reorganization strategy for the synthesis of benzene-containing products from the kojic acid-and maltol-derived alkynes has been recently reported.In this strategy,kojic acid and maltol are analogou...The deconstructive reorganization strategy for the synthesis of benzene-containing products from the kojic acid-and maltol-derived alkynes has been recently reported.In this strategy,kojic acid and maltol are analogous to the"Transformers",which can transform into benzofurans and benzaldehydes via annulation reactions.Under the synthetic standpoint,this deconstructive reorganization strategy features high atom economy,innate scalability and functional group tolerance.In the near future,we believe that this unique method will be widely investigated a nd other novel transformations of kojic acid and maltol will be discovered.展开更多
Two new benzofuran lignan glycosides, gelsemiunoside A and B, were isolated from the whole plant of Gelsemium elegans Benth. Their structures were elucidated on the basis of spectroscopic evidence. Furthermore, gelsem...Two new benzofuran lignan glycosides, gelsemiunoside A and B, were isolated from the whole plant of Gelsemium elegans Benth. Their structures were elucidated on the basis of spectroscopic evidence. Furthermore, gelsemiunoside A and B were shown a potent cytotoxic activity by suppressing the proliferation of A375-S2 cells.展开更多
Objective:To find out the in vitro antipalsmodial activities of mangrove leaf extracts.Methods: In vitro antiplasmodial assay was carried out with 13 different mangrove plants.Column chromatography was performed with ...Objective:To find out the in vitro antipalsmodial activities of mangrove leaf extracts.Methods: In vitro antiplasmodial assay was carried out with 13 different mangrove plants.Column chromatography was performed with the most potent Agecerious corniculatum（A.corniculatum） by using various solvent extractions.GC-MS was also preformed with the most potent ethanolic fraction of the A.corniculatum extract.Results:Of the 13 mangroves plants, A.corniculatum showed maximum percentage of parasitemia suppression（94.98±1.16）%.Column chromatography was performed with A.corniculatum with different solvents and the methanolic extract showed maximum percentage（99.73±1.63）%of parasitemia inhibition at 150μg/mL concentration with the IC<sub>50</sub> value of（29.28±3.23）μg/mL concentration.The results of the GC-MS analysis observed that,the most potent methanolic extract showed maximum retention time（30.687 RT） and the chemical class was identified as Spiro[benzofuran-2（3 H）,1’-（3 cyclohexane）-2’,3- dione,7-chloro-4’,6]which was responsible for the antiplasmodial activity.Conclusions:It is concluded from the present study that,the chemical constituents of A.corniculatum collected from Pichavaram mangrove forest can be used as a putative antiplasmodial drugs in future.展开更多
A series of novel benzofuran-isatin-hydroxylimine/thiosemicarbazide hybrids were designed, synthesized and evaluated for their in vitro anti-TB activities against drug-sensitive MTB H_(37)Rv and MDR-TB isolates as wel...A series of novel benzofuran-isatin-hydroxylimine/thiosemicarbazide hybrids were designed, synthesized and evaluated for their in vitro anti-TB activities against drug-sensitive MTB H_(37)Rv and MDR-TB isolates as well as cytotoxicity. All benzofuran-isatin-hydroxylimine/thiosemicarbazide hybrids exhibited considerable in vitro anti-mycobacterial activities against the tested three MTB strains, and all of them also showed acceptable cytotoxicity. The most active hybrid 7f was >4.8 and >51 folds more potent than the first line anti-TB agents RIF and INH against both drug-sensitive MTB H_(37)Rv and MDR-TB isolates, respectively. The results demonstrated the potential utility of benzofuran-isatin-hydroxylimine/-thiosemicarbazide hybrids as anti-TB agents.展开更多
A new bisbenzofuran analogue Ⅶ was achieved unexpectedly in one step procedure from 1-（4-methoxyphenoxy）acetone Ⅰ by using Amberlyst 15 resin as catalyst in excellent yield. The structure was elucidated by spectro...A new bisbenzofuran analogue Ⅶ was achieved unexpectedly in one step procedure from 1-（4-methoxyphenoxy）acetone Ⅰ by using Amberlyst 15 resin as catalyst in excellent yield. The structure was elucidated by spectroscopy analysis including ^1H-NMR, ^13C-NMR, DEPT, ESI-MS, element analysis.展开更多
The Al-doped Ni2P/AI-SBA-15 catalyst with high hydrodeoxygenation （HDO） activity was synthesized by tem- perature programmed reduction at a relatively low reduction temperature of 400 ℃. The as-prepared catalyst wa...The Al-doped Ni2P/AI-SBA-15 catalyst with high hydrodeoxygenation （HDO） activity was synthesized by tem- perature programmed reduction at a relatively low reduction temperature of 400 ℃. The as-prepared catalyst was characterized by X-ray diffraction （XRD）, H2 temperature-programmed reduction （H2-TPR）, X-ray photoelectron spectroscopy （XPS）, transmission electron microscope （TEM）, NH3 temperature programmed desorption （NH3-TPD）, N2 adsorption-desorption and CO uptake. The effect of AI on benzofuran （BF） HDO performance was investigated. The result indicates that the incorporation of AI into the SBA-15 support can promote the formation of much uniform, smaller, highly dispersed N2P particles on the catalyst. The AI also contrib- utes to suppress the enrichment of P and promote more exposed Ni sites on the surface. In addition, the incorporation of AI can enhance the acid strength. The total deoxygenated product yield over Ni2P/AI-SBA-15 reached 90.3%, which is an increase of 19.4%, when compared with that found for Ni2P/SBA-15 （70.9%）.展开更多
l-Methyl-3-ethyl imidazolium bromide[meim]Br/basic alumina（Al2O3） has been found to promote the cyclocondensation of chloroacetone/chloroethyl acetate with salicylaldehydes under conventional as well as microwave ir...l-Methyl-3-ethyl imidazolium bromide[meim]Br/basic alumina（Al2O3） has been found to promote the cyclocondensation of chloroacetone/chloroethyl acetate with salicylaldehydes under conventional as well as microwave irradiation to yield benzofuran derivatives.展开更多
Plant-parasitic nematodes are major threat for crop protection.The lack of nematicides with new mode of action and increasing resistance raises the need for novel nematicides.In order to seek new nematicidal lead,orig...Plant-parasitic nematodes are major threat for crop protection.The lack of nematicides with new mode of action and increasing resistance raises the need for novel nematicides.In order to seek new nematicidal lead,originating from the structure of chalcone,a series of fused ring compounds was obtained by ring closure design strategy.These compounds were modified further.The nematicidal activity against M.incognita of synthesized compounds was evaluated.The bioassay showed that compound 3 and some of its derivatives such as compounds 18,19,21,22,23,24 and 26 exhibited excellent nematicidal activity.Among them,compound 23 exhibited significant bioactivity.The LC50/72 hvalue reached 3.20 mg/L in vitro and the inhibition rate was 100.00%at 40 mg/L in the matrix.The structure-activity relationship of synthesized compounds was discussed in details.The influence of compound 23 on egg hatching,motility,and feeding behavior of C.elegans was also evaluated.展开更多
The chiral N-heterocyclic carbene-catalyzed [4 ＋ 2] annulation of a-chloroaldehydes and aurones was developed, giving the corresponding benzofuran–fused dihydropyranones in good to high yields with good diastereosel...The chiral N-heterocyclic carbene-catalyzed [4 ＋ 2] annulation of a-chloroaldehydes and aurones was developed, giving the corresponding benzofuran–fused dihydropyranones in good to high yields with good diastereoselectivities and excellent enantioselectivities. The catalytic cycle features with the generation of enolate from chloroaldehdye and its following [4 ＋ 2] cycloaddtion with aurones.展开更多
基金supported by the Natural Science Foundation of Shandong Province (No. ZR2018MB009)the International Cooperation Project of Qinghai Province (No. 2018-HZ-806)+1 种基金the Qinghai Key Laboratory of Tibetan Medicine Research (No. 2017-ZJ-Y11)the National Natural Science Foundation of China (No. 21302109)
文摘A new and convenient visible-light-induced method has been developed for the synthesis of sulfonylated benzofurans via oxidative cyclization reaction of 1,6-enynes and arylsulfinic acids.This reaction was carried out under metal-free and mild conditions,in which the C-S,C-C and C=O bonds could be sequentially formed in one pot operation.
基金the National Key R&D Program of China (No. 2016YFA0202900)National Basic Research Program of China (No.2015CB856600)+1 种基金the National Natural Science Foundation of China (Nos. 21332009, 21421091)the Chinese Academy of Sciences (Nos. XDB20000000, QYZDY-SSW-SLH012) for generous financial support
文摘A catalytic asymmetric brominative dearomatization reaction of benzofuran derivatives was achieved by using hydroquinidine 1,4-phthalazinediyl diether [（DHQ）_2PHAL] as the catalyst and N-bromoacetamide（NBAc） as the brominating reagent. A series of brominated spiro[benzofuran-2,5＇-oxazoles] bearing two contiguous stereogenic centers were obtained in high yields（up to 99%） with excellent enantioselectivity（up to 97% ee）.
基金supported by the National Natural Science Foundation of China(22278200,21971095,21502080,21772019,21772076,21871117,91956203)the National Key R&D Program of China(2023YFA1506400)+3 种基金the Science and Technology Major Program of Gansu Province of China(22ZD6FA006,23ZDFA015)the“111”Program of Ministry of Education of Chinathe Major Project of the Ministry of Science and Technology of China(2018ZX09711001-005-002)the Science and Technology Commission of Shanghai Municipality(19JC1430100)。
文摘Herein,the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO)complex catalyze asymmetric formal[3+2]cycloaddition between quinones and ynamides is explored,producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities.Furthermore,density functional theory calculations were applied to explain the possible reaction mechanism.
基金the Science and Technology Foundation of Henan Province(222102310580)Innovation and Entrepreneurship Training Program for College StudentsHenan University of Science and Technology(2023180).
文摘Chemodivergent synthesis of benzofurans and 2,3-dihydrobenzofurans has been realized.Under a reaction system consisting of DBDMH and K_(2)CO_(3) as promotors,controlled conditions enabled the formation of two sets of valuable heterocycles from the tandem transformation of enaminones and salicylaldehydes.The key to success was the identification of the reaction parameters,in which the imine intermediate which was formed by transient halogenation coupling and substitution processes underwent either aldol condensation/annulation or imine hydrolysis/aldol condensation.The additives NH_(4)Cl or Fe_(2)(SO_(4))_(3) controlled the unique selectivity of this reaction.A broad substrate scope of enaminones and salicylaldehydes has been employed in this reaction,demonstrating excellent functional group tolerance and versatility.
基金The authors thank the National Natural Science Foundation of China(21462038)Key Laboratory of Eco-Environment-Related Polymer Materials of the Ministry of Education of China for their financial support for this work.
文摘A one-pot three-component method for the synthesis of 2-methyl-3-aminobenzofurans using calcium carbide as a concise solid alkyne source,and salicylaldehydes and secondary amines as starting materials is described.This protocol has salient feature of the use of inexpensive,abundant and easy-to-handle alkyne source,avoiding the use of inflammable and explosive acetylene gas as an original alkyne source.In addition,step economy,satisfactory yield,and simple work-up procedure are also advantages of this route.
基金supported by National Natural Science Foundation of China(grant no.21772183)the Fundamental Research Funds for the Central Universities(grant no.WK2060190086)“1000-Youth Talents Plan”start-up funding as well as the University of Science and Technology of China.
文摘In this paper,we developed an electrophilic ring-opening reaction,which is beyond the strained small ring system.Under reductive nickel catalysis,ring-opening of diverse benzofurans via endocyclic inert carbon–oxygen bond cleavage can be achieved with an array of inactivated secondary and tertiary alkyl halides as coupling partners,allowing for the preparation of a series of(E)-o-alkenylphenols with excellent E/Z-selectivity and high functional tolerance.The utility of this method was further demonstrated through derivatizations of the ring-opening products using the o-hydroxyl group as a functional handle,providing various organic compounds in good to high efficiency.
文摘Benzofuran is an essential structural component found in a wide range of natural products,agrochemicals and drugs,possessing a range of biological activities.In recent years,there have been numerous reports of successful syntheses of benzofuran derivatives via intra-and inter-molecular cyclizations using diverse catalysts.This review gives an exhaustive and methodical survey of the procedures for making benzofurans.
文摘Flavonoids are by far the most dominant class of phenolic compounds isolated from Morus alba leaves(MAL). Other classes of compounds are benzofurans, phenolic acids, alkaloids, coumarins, chalcones and stilbenes. Major flavonoids are kuwanons, moracinflavans, moragrols and morkotins. Other major compounds include moracins(benzofurans), caffeoylquinic acids(phenolic acids) and morachalcones(chalcones). Research on the anticancer properties of MAL entailed in vitro and in vivo cytotoxicity of extracts or isolated compounds. Flavonoids, benzofurans, chalcones and alkaloids are classes of compounds from MAL that have been found to be cytotoxic towards human cancer cell lines. Further studies on the phytochemistry and anticancer of MAL are suggested. Sources of information were Pub Med,Pub Med Central, Science Direct, Google, Google Scholar, J-Stage, Pub Chem and China National Knowledge Infrastructure.
文摘The root bark of Morus alba L. or white mulberry is widely used as traditional medicine in China, Japan and Korea. Major classes and types of phenolic compounds isolated from the root bark are flavonoids(kuwanons, morusin, cyclomorusin and sanggenons), benzofurans(moracins and mulberrofurans), and stilbenoids(mulberrosides). Some of the flavonoids and benzofurans are products of Diel-Alder type adducts. Other classes of compounds include triterpenes, phenolic acids and coumarins. Morusin, a prenylated flavonoid, was first isolated from the root bark of M. alba, and later from the leaf, stem bark and twig of the plant. The potent anti-cancer properties of morusin have attracted much attention with research on-going and new findings being published. The compound inhibits angiogenesis, tumour progression and tumour migration, and triggers apoptosis, cell cycle arrest and autophagy in colorectal, cervical, prostate, breast, hepatoma, pancreatic, glioblastoma, gastric, ovarian and lung cancer cell lines. The anti-cancer activities of morusin are executed via various molecular targets and signalling pathways. It is anticipated that on-going in vitro studies will progress gradually to in vivo studies using animal models before efforts towards drug development can be initiated for clinical trials.
文摘AIM:To investigate the pathway(s)mediating rat antral circular smooth muscle contractile responses to the cholinomimetic agent,bethanechol and the subtypes of muscarinic receptors mediating the cholinergic contraction. METHODS:Circular smooth muscle strips from the antrum of Sprague-Dawley rats were mounted in muscle baths in Krebs buffer.Isometric tension was recorded.Cumulative concentration-response curves were obtained for(+)-cis- dioxolane(cD),a nonspecific muscarinic agonist,at 10^(-8)- 10^(-4)mol/L,in the presence of tetrodotoxin(TTX,10^(-7)mol/L). Results were normalized to cross sectional area.A repeat concentration-response curve was obtained after incubation of the muscle for 90 min with antagonists for M1(pirenzepine), M2(methoctramine)and M3(darifenadn)muscarinic receptor subtypes.The sensitivity to PTX was tested by the ip injection of 100 mg/kg of PTX 5 d before the experiment.The antral circular smooth muscles were removed from PTX-treated and non-treated rats as strips and dispersed smooth muscle cells to identify whether PTX-linked pathway mediated the contractility to bethanechol. RESULTS:A dose-dependent contractile response observed with bethanechol,was not affected by TTx.The pretreatment of rats with pertussis toxin decreased the contraction induced by bethanechol.Lack of calcium as well as the presence of the L-type calcium channel blocker,nifedipine,also inhibited the cholinergic contraction,with a reduction in response from 2.5±0.4 g/mm^2 to 1.2±0.4 g/mm^2(P<0.05).The dose- response curves were shifted to the right by muscarinic antagonists in the following order of affinity:darifenacin (M_3)>methocramine(M_2)>pirenzepine(M_1). CONCLUSION:The muscarinic receptors-dependent contraction of rat antral circular smooth muscles was linked to the signal transduction pathway(s)involving pertussis-toxin sensitive GTP-binding proteins and to extracellular calcium via L-type voltage gated calcium channels.The presence of the residual contractile response after the treatment with nifedipine,suggests that an additional pathway could mediate the cholinergic contraction.The involvement of more than one muscarinic receptor(functionally predominant type 3 over type 2)also suggests more than one pathway mediating the cholinergic contraction in rat antrum.
基金the National Natural Science Foundation of China(Nos.21871053 and 21532001)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(No.2019R01005)。
文摘The deconstructive reorganization strategy for the synthesis of benzene-containing products from the kojic acid-and maltol-derived alkynes has been recently reported.In this strategy,kojic acid and maltol are analogous to the"Transformers",which can transform into benzofurans and benzaldehydes via annulation reactions.Under the synthetic standpoint,this deconstructive reorganization strategy features high atom economy,innate scalability and functional group tolerance.In the near future,we believe that this unique method will be widely investigated a nd other novel transformations of kojic acid and maltol will be discovered.
基金sponsored by the Scientific Research Foundation for the doctoral Scholars (Q.C.Zhao,No.20031040),Liaoning,China.
文摘Two new benzofuran lignan glycosides, gelsemiunoside A and B, were isolated from the whole plant of Gelsemium elegans Benth. Their structures were elucidated on the basis of spectroscopic evidence. Furthermore, gelsemiunoside A and B were shown a potent cytotoxic activity by suppressing the proliferation of A375-S2 cells.
基金Indian Council of Medical Research,New Dclhi for financial assistance
文摘Objective:To find out the in vitro antipalsmodial activities of mangrove leaf extracts.Methods: In vitro antiplasmodial assay was carried out with 13 different mangrove plants.Column chromatography was performed with the most potent Agecerious corniculatum（A.corniculatum） by using various solvent extractions.GC-MS was also preformed with the most potent ethanolic fraction of the A.corniculatum extract.Results:Of the 13 mangroves plants, A.corniculatum showed maximum percentage of parasitemia suppression（94.98±1.16）%.Column chromatography was performed with A.corniculatum with different solvents and the methanolic extract showed maximum percentage（99.73±1.63）%of parasitemia inhibition at 150μg/mL concentration with the IC<sub>50</sub> value of（29.28±3.23）μg/mL concentration.The results of the GC-MS analysis observed that,the most potent methanolic extract showed maximum retention time（30.687 RT） and the chemical class was identified as Spiro[benzofuran-2（3 H）,1’-（3 cyclohexane）-2’,3- dione,7-chloro-4’,6]which was responsible for the antiplasmodial activity.Conclusions:It is concluded from the present study that,the chemical constituents of A.corniculatum collected from Pichavaram mangrove forest can be used as a putative antiplasmodial drugs in future.
文摘A series of novel benzofuran-isatin-hydroxylimine/thiosemicarbazide hybrids were designed, synthesized and evaluated for their in vitro anti-TB activities against drug-sensitive MTB H_(37)Rv and MDR-TB isolates as well as cytotoxicity. All benzofuran-isatin-hydroxylimine/thiosemicarbazide hybrids exhibited considerable in vitro anti-mycobacterial activities against the tested three MTB strains, and all of them also showed acceptable cytotoxicity. The most active hybrid 7f was >4.8 and >51 folds more potent than the first line anti-TB agents RIF and INH against both drug-sensitive MTB H_(37)Rv and MDR-TB isolates, respectively. The results demonstrated the potential utility of benzofuran-isatin-hydroxylimine/-thiosemicarbazide hybrids as anti-TB agents.
基金supported by the National Natural Science Foundation of China(20472117,20272085)the Natural Science Foundation of Guangdong Province(031594).
文摘A new bisbenzofuran analogue Ⅶ was achieved unexpectedly in one step procedure from 1-（4-methoxyphenoxy）acetone Ⅰ by using Amberlyst 15 resin as catalyst in excellent yield. The structure was elucidated by spectroscopy analysis including ^1H-NMR, ^13C-NMR, DEPT, ESI-MS, element analysis.
文摘The Al-doped Ni2P/AI-SBA-15 catalyst with high hydrodeoxygenation （HDO） activity was synthesized by tem- perature programmed reduction at a relatively low reduction temperature of 400 ℃. The as-prepared catalyst was characterized by X-ray diffraction （XRD）, H2 temperature-programmed reduction （H2-TPR）, X-ray photoelectron spectroscopy （XPS）, transmission electron microscope （TEM）, NH3 temperature programmed desorption （NH3-TPD）, N2 adsorption-desorption and CO uptake. The effect of AI on benzofuran （BF） HDO performance was investigated. The result indicates that the incorporation of AI into the SBA-15 support can promote the formation of much uniform, smaller, highly dispersed N2P particles on the catalyst. The AI also contrib- utes to suppress the enrichment of P and promote more exposed Ni sites on the surface. In addition, the incorporation of AI can enhance the acid strength. The total deoxygenated product yield over Ni2P/AI-SBA-15 reached 90.3%, which is an increase of 19.4%, when compared with that found for Ni2P/SBA-15 （70.9%）.
文摘l-Methyl-3-ethyl imidazolium bromide[meim]Br/basic alumina（Al2O3） has been found to promote the cyclocondensation of chloroacetone/chloroethyl acetate with salicylaldehydes under conventional as well as microwave irradiation to yield benzofuran derivatives.
基金financial supported by the National Natural Science Foundation of China(No.21672061)National Key Research Program of China(No.2018YFD0200105)+1 种基金supported by Innovation Program of Shanghai Municipal Education Commission(No.201701070002E00037)the Fundamental Research Funds for the Central Universities。
文摘Plant-parasitic nematodes are major threat for crop protection.The lack of nematicides with new mode of action and increasing resistance raises the need for novel nematicides.In order to seek new nematicidal lead,originating from the structure of chalcone,a series of fused ring compounds was obtained by ring closure design strategy.These compounds were modified further.The nematicidal activity against M.incognita of synthesized compounds was evaluated.The bioassay showed that compound 3 and some of its derivatives such as compounds 18,19,21,22,23,24 and 26 exhibited excellent nematicidal activity.Among them,compound 23 exhibited significant bioactivity.The LC50/72 hvalue reached 3.20 mg/L in vitro and the inhibition rate was 100.00%at 40 mg/L in the matrix.The structure-activity relationship of synthesized compounds was discussed in details.The influence of compound 23 on egg hatching,motility,and feeding behavior of C.elegans was also evaluated.
基金The Financial support from the National Natural Science Foundation of China (Nos. 21425207, 21521002)the Chinese Academy of Sciences is greatly acknowledged
文摘The chiral N-heterocyclic carbene-catalyzed [4 ＋ 2] annulation of a-chloroaldehydes and aurones was developed, giving the corresponding benzofuran–fused dihydropyranones in good to high yields with good diastereoselectivities and excellent enantioselectivities. The catalytic cycle features with the generation of enolate from chloroaldehdye and its following [4 ＋ 2] cycloaddtion with aurones.
