Four new phenolic amides,4-O-methylgrossamide(1),(E)-2-(4,5-dihydroxy-2-{3-[(4-hydrox-yphenethyl)amino]-3-oxopropyl}-phenyl)-3-(4-hydroxy-3-methoxyphenyl)-N-(4-hydroxyphenethyl)acryl-amide(2),(Z)-lyciumamide C(3),(Z)-...Four new phenolic amides,4-O-methylgrossamide(1),(E)-2-(4,5-dihydroxy-2-{3-[(4-hydrox-yphenethyl)amino]-3-oxopropyl}-phenyl)-3-(4-hydroxy-3-methoxyphenyl)-N-(4-hydroxyphenethyl)acryl-amide(2),(Z)-lyciumamide C(3),(Z)-thoreliamide B(4),together with thirteen known phenolic amides were identified from the stem of Lycium barbarum.The structures of the new compounds were determined by spectroscopic methods.All compounds were evaluated for their anti-cancer activities against human glioma stem cell lines.展开更多
One undescribedamide,pipermullesine A,twoundescribed isoquinoline alkaloids,pipermullesinesBand C,and six undescribed dipeptides,pipermullamides A–F,along with 28 known compounds,were isolated from the aerial parts o...One undescribedamide,pipermullesine A,twoundescribed isoquinoline alkaloids,pipermullesinesBand C,and six undescribed dipeptides,pipermullamides A–F,along with 28 known compounds,were isolated from the aerial parts of Piper mullesua.The structures of the undescribed compounds were elucidated based on the analysis of 1D and 2D NMR and MS data.Furthermore,the structures of pipermullesines A–Cwere confirmed by single crystal X-ray diffraction analysis.All isolates were evaluated for inhibitory activity against platelet aggregation induced by thrombin(IIa)or platelet-activating factor(PAF).(-)-Mangochinine,pellitorine,and(2E,4E)-N-isobutyl-2,4-dodecadienamide showed weak inhibitory activity against rabbit platelet aggregation induced by PAF,with IC_(50)values of 470.3μg/mL,614.9μg/mL,and 579.7μg/mL,respectively.展开更多
Indium(III) triflate, a trivalent indium reagent, was shown to be a highly-efficient catalyst for the conversion of primary amides to the corresponding nitriles. The successful reactions required 5 mol% of indium(III)...Indium(III) triflate, a trivalent indium reagent, was shown to be a highly-efficient catalyst for the conversion of primary amides to the corresponding nitriles. The successful reactions required 5 mol% of indium(III) triflate, and toluene was proved to be the most suitable solvent. Various amides were subjected to this method, and each produced the corresponding nitriles in excellent yields.展开更多
?β-Unsaturated amides with various substitution pattems at the carbon-carbon double And and nitrogen atom can be reduced to the corresponding saturated amides with high selectivity and yields with NaBH4/BiCl3 system.
Two new amides(E)-N-cinnamoyl-2-methoxypiperidine(1)and(R)-1-(2-oxopyrrolidin-3-yl)-5,6-dihydropyridin-2(1H)-one(2),four new amide glucosides,retrofractosides A-D(3-6),and two new phenylpropanoid glucosides,retrofract...Two new amides(E)-N-cinnamoyl-2-methoxypiperidine(1)and(R)-1-(2-oxopyrrolidin-3-yl)-5,6-dihydropyridin-2(1H)-one(2),four new amide glucosides,retrofractosides A-D(3-6),and two new phenylpropanoid glucosides,retrofractosides E(7)and F(8),together with 24 known compounds(9-32)were isolated from the fruits of Piper retrofractum.The chemical structures of these new compounds were elucidated based on extensive spectroscopic analysis.All of these isolates(1-32)were evaluated for inhibitory activity against mouse platelet aggregation induced by the peptide AYPGKF-NH2.(E)-N-(Tetrahydro-2H-pyran-2-yl)cinnamamide(9)showed a weak inhibitory efect,with an inhibition ratio of 52.0%at a concentration of 150μM.展开更多
A novel aromatic diamine, 1, 2-dihydro-2-(4-aminophenyl)-4-[3-methoxy-4-(4-aminophenoxy)]-2, 3-phthalazin-l-one (OO-DA) containing aza heterocyclic structure was synthesized from the bisphenol-like monomer in tw...A novel aromatic diamine, 1, 2-dihydro-2-(4-aminophenyl)-4-[3-methoxy-4-(4-aminophenoxy)]-2, 3-phthalazin-l-one (OO-DA) containing aza heterocyclic structure was synthesized from the bisphenol-like monomer in two steps and used for preparing new aromatic polyamides with high inherent viscosity of 0.89-1.03 dL.g^-1. The structures of diamine and polymers obtained were confirmed by MS, PT-IR, WAXD and ^1H-NMR. The synthesized polymers exhibited high glass transition temperature in the range of 281-307℃ and good solubility in polar solvents.展开更多
A convenient method for preparing unsaturated amides via telluro- nium salts employing solid potassium carbonate as a base with high stereo- selectivity in excellent yields has been developed.
Developing mild and efficient catalytic methods for the selective synthesis of amines is a longstanding research objective.In this respect,catalytic deoxygenative amide reduction has proven to be promising but challen...Developing mild and efficient catalytic methods for the selective synthesis of amines is a longstanding research objective.In this respect,catalytic deoxygenative amide reduction has proven to be promising but challenging,as this approach necessitates selective C-O bond cleavage.Herein,we report the selective hydroboration of primary,secondary,and tertiary amides at room temperature catalyzed by an earth-abundant-metal catalyst,Zr-H,for accessing diverse amines.Various readily reducible functional groups,such as esters,alkynes,and alkenes,were well tolerated.Furthermore,the methodology was extended to the synthesis of bio-and drug-derived amines.Detailed mechanistic studies revealed a reaction pathway entailing aldehyde and amido complex formation via an unusual C-N bond cleavage-reformation process,followed by C-O bond cleavage.展开更多
The methanolysis of amides,which is widely employed in the synthetic organic chemistry,hardly occurs under mild conditions.To safely and controllably intensify the methanolysis reaction with hightemperature and high-p...The methanolysis of amides,which is widely employed in the synthetic organic chemistry,hardly occurs under mild conditions.To safely and controllably intensify the methanolysis reaction with hightemperature and high-pressure environment,a continuous tubular reaction technology is developed,whose space-time yield is over twice of that of the conventional batch reaction.The methanolysis of acetanilide is selected as the representative reaction,and the influences of temperature,pressure,reactant and catalyst concentration,and residence time on the reaction performances are systematically investigated.Taking the advantages of precise temperature and reaction time control by the tubular reactor,the kinetics of acetanilide methanolysis are determined and compared to the kinetics of acetanilide hydrolysis reaction.The tubular reaction method is also employed to test a variety of other amides to show the effects of substituents,steric hindrance,and alkalinity on the reaction rate of methanolysis.展开更多
An interesting reaction procedure for the cross-coupling of potassium styryltrifluoroborates and amides has been developed by using PdCl2(dtbpf)-CuI dual catalyst system. By applying this method, good numbers of amide...An interesting reaction procedure for the cross-coupling of potassium styryltrifluoroborates and amides has been developed by using PdCl2(dtbpf)-CuI dual catalyst system. By applying this method, good numbers of amide styrylation products are formed in 85% - 92% yields.展开更多
A new robust heterogeneous, versatile, an environmentally benign, eco-friendly, recyclable CuFAP catalyst has been developed for the direct synthesis of nitriles and amides from aldehydes at 100°C for 6 h and 4 h...A new robust heterogeneous, versatile, an environmentally benign, eco-friendly, recyclable CuFAP catalyst has been developed for the direct synthesis of nitriles and amides from aldehydes at 100°C for 6 h and 4 h, respectively, under neat reaction condition using hydroxylamine hydrochloride in the presence and the absence of tosyl chloride, respectively. Also the recyclability of catalyst as well as influence of solvents, additives on catalysts performance was investigated. The protocol can be considered as an alternative to conventional method for the synthesis of nitriles and amides in good to excellent yields. A highlight of our protocol is the easy separation of catalyst from reaction mixture, hence the catalyst is reused several times without significant loss of its catalytic activity.展开更多
The first asymmetric hydrogenation of acyclic tetrasubstitutedα,β-unsaturated amides has been achieved by using Rh/DuanPhos complex as a catalyst,delivering chiralβ-amino amides with two contiguous chiral centers i...The first asymmetric hydrogenation of acyclic tetrasubstitutedα,β-unsaturated amides has been achieved by using Rh/DuanPhos complex as a catalyst,delivering chiralβ-amino amides with two contiguous chiral centers in excellent yields and high enantioselectivities(up to 99%yield,96%ee),which provides efficient and concise access to valuableβ-amino amide derivatives.The gram-scale reaction and efficient transformation ofβ-amino amide toβ-amino acid andβ-amino cyanide demonstrated the utility of this methodology.展开更多
Herein,we report a condition-controlled divergent synthesis of spiro indene-2,1'-isoindolinones and spiro isochroman-3,1'-isoindolinones through cobalt-catalyzed formal[4+1]and[4+1+1]spirocyclization of aromat...Herein,we report a condition-controlled divergent synthesis of spiro indene-2,1'-isoindolinones and spiro isochroman-3,1'-isoindolinones through cobalt-catalyzed formal[4+1]and[4+1+1]spirocyclization of aromatic amides with 2-diazo-1H-indene-1,3(2H)-dione.When the reaction is carried out under air in ethyl acetate,spiro indene-2,1'-isoindolinones are formed through Co(II)-catalyzed C—H/N—H[4+1]spirocyclization.When the reaction is run under O2 in CH3CN,on the other hand,spiro isochroman-3,1'-isoindolinones are generated through Baeyer-Villiger oxidation of the in situ formed spiro indene-2,1'-isoindolinones with O2 as a cheaper and environmental-friendly oxygen source.In general,these protocols have advantages such as using non-precious and earth-abundant metal catalyst,no extra additive,high efficiency and regioselectivity.A gram-scale synthesis and the removal of the directing group further highlight its utility.展开更多
Catalytic Michael addition reaction represents a fundamental importance in organic synthetic chemistry.Whereas corresponding conversions toward intrinsically low reactive enamide remains an ongoing challenging.We here...Catalytic Michael addition reaction represents a fundamental importance in organic synthetic chemistry.Whereas corresponding conversions toward intrinsically low reactive enamide remains an ongoing challenging.We herein report a copper-catalyzed conjugate addition of allenes toβ-substituted alkenyl amides,one of the most challenging Michael acceptors.The present method utilizes readily available allenes as the latent carbon-based nucleophiles and simple,commonβ-substituted alkenyl amides as starting materials,unlike previous methods that usually preinstall an activating group to improve the reactivity of amide or uses highly reactive stoichiometric quantities of organometallics.Hence,this approach shows good functional group compatibility and can be implemented under mild reaction conditions with excellent level of chemo-and regioselectivities.展开更多
In sharp contrast to the well researched and well developed aminocarbonylation of alkenes,the dearomative carbamoylation of abundant areneπ-systems has scarcely been studied despite its great potential to enrich the ...In sharp contrast to the well researched and well developed aminocarbonylation of alkenes,the dearomative carbamoylation of abundant areneπ-systems has scarcely been studied despite its great potential to enrich the diversity-oriented synthesis of high-value amides.The formidable challenges associated with such dearomatization include the low reactivity of stable aromaticπ-systems and intricate selectivity issues.Herein,we disclose a general approach toward highly selective dearomative carbamoylations of areneπ-bonds under CO-gas-free conditions.Its extraordinary versatility was demonstrated by tolerating a broad range of nucleophilic partners with high yields and excellent selectivities,thus providing modular access to the divergent synthesis ofβ-functionalized primary amides.In addition,diverse downstream derivatizations including a formal C–H 1,2-olefination/carbamoylation reaction were conducted,exhibiting great potential in synthetic and medicinal chemistry.展开更多
A highly efficient copper-catalyzed approach to form amide bonds from formamides and carboxylic acids was developed. This protocol shows broad substrate scopes and high yields in the presence of 1 mol% catalyst and 4....A highly efficient copper-catalyzed approach to form amide bonds from formamides and carboxylic acids was developed. This protocol shows broad substrate scopes and high yields in the presence of 1 mol% catalyst and 4.0 equiv, formamides.展开更多
Background Gastric cancer (GC) is one of the most common types of cancer in the world. A change in the metabolism of lipids in tumor cells could lead to the pathogenesis of cancer. In this study, we investigated fat...Background Gastric cancer (GC) is one of the most common types of cancer in the world. A change in the metabolism of lipids in tumor cells could lead to the pathogenesis of cancer. In this study, we investigated fatty acid and fatty acid amide metabolic perturbations associated with GC morbidity.展开更多
The direct partial reduction of highly stable secondary amides to more reactive aldimines and aldehydes is a challenging yet highly demanding transformation. In this context, only three methods have been reported. We ...The direct partial reduction of highly stable secondary amides to more reactive aldimines and aldehydes is a challenging yet highly demanding transformation. In this context, only three methods have been reported. We report herein an improved version of the Charette's method. Our protocol consists of activation of secondary amides with triflic anhydride/2-fluoropyridine,and partial reduction of the resulting intermediates with 1,1,3,3-tetramethyldisiloxane(TMDS), which delivered aldimines or aldehydes upon acidic hydrolysis. Aromatic amides were reduced to the corresponding aldimines in 85%–100% NMR yields,and yields(NMR) from aliphatic amides were 72%–86%. Acidic hydrolysis of the aldimine intermediates afforded, in one-pot,the corresponding aldehydes in 80%–96% yields. A simple protocol was established to isolate labile aldimines in pure form in92%–96% yields. The improved method gave generally higher yields as compared to the known ones, and features the use of cheaper and more atom-economical TMDS as a chemoselective reducing agent. In addition, a convenient extraction protocol has been established to allow the isolation of amines, which constitutes a mild method for the N-deacylation of amides, another highly desirable transformation. The extended method retains the advantages of the original method of Charette in terms of mild conditions, good functional group tolerance, and excellent chemoselectivity.展开更多
基金The authors are grateful to agricultural com-prehensive development project of science and technology in Ningxia province(Research on Chinese wolfberry active substances and health products)STS project of Chinese Academy of Sciences for the financial support.
文摘Four new phenolic amides,4-O-methylgrossamide(1),(E)-2-(4,5-dihydroxy-2-{3-[(4-hydrox-yphenethyl)amino]-3-oxopropyl}-phenyl)-3-(4-hydroxy-3-methoxyphenyl)-N-(4-hydroxyphenethyl)acryl-amide(2),(Z)-lyciumamide C(3),(Z)-thoreliamide B(4),together with thirteen known phenolic amides were identified from the stem of Lycium barbarum.The structures of the new compounds were determined by spectroscopic methods.All compounds were evaluated for their anti-cancer activities against human glioma stem cell lines.
基金This work was funded by the Southeast Asia Biodiversity Research Institute,Chinese Academy of Sciences(Y4ZK111B01)the Natural Science Foundation of Yunnan Province,China(2011FZ205)+2 种基金the International Partneship Program of Chinese Academy of Sciences(153631KYSB20160004)the Key Laboratory of Ethnomedicine(Minzu University of China)of Ministry of Education of China(KLEM-ZZ201806)the National Natural Science Foundation of China(31761143001&31161140345).
文摘One undescribedamide,pipermullesine A,twoundescribed isoquinoline alkaloids,pipermullesinesBand C,and six undescribed dipeptides,pipermullamides A–F,along with 28 known compounds,were isolated from the aerial parts of Piper mullesua.The structures of the undescribed compounds were elucidated based on the analysis of 1D and 2D NMR and MS data.Furthermore,the structures of pipermullesines A–Cwere confirmed by single crystal X-ray diffraction analysis.All isolates were evaluated for inhibitory activity against platelet aggregation induced by thrombin(IIa)or platelet-activating factor(PAF).(-)-Mangochinine,pellitorine,and(2E,4E)-N-isobutyl-2,4-dodecadienamide showed weak inhibitory activity against rabbit platelet aggregation induced by PAF,with IC_(50)values of 470.3μg/mL,614.9μg/mL,and 579.7μg/mL,respectively.
文摘Indium(III) triflate, a trivalent indium reagent, was shown to be a highly-efficient catalyst for the conversion of primary amides to the corresponding nitriles. The successful reactions required 5 mol% of indium(III) triflate, and toluene was proved to be the most suitable solvent. Various amides were subjected to this method, and each produced the corresponding nitriles in excellent yields.
文摘?β-Unsaturated amides with various substitution pattems at the carbon-carbon double And and nitrogen atom can be reduced to the corresponding saturated amides with high selectivity and yields with NaBH4/BiCl3 system.
基金supported by the Southeast Asia Biodiversity Research Institute,Chinese Academy of Sciences(2015CASEABRIRG001 and Y4ZK111B01)the open foundation of Key Laboratory of Ethnomedicine(Minzu University of China),Ministry of Education(KLEM-KF2018Z01)the International Partnership Program of Chinese Academy of Sciences(153631KYSB20160004).
文摘Two new amides(E)-N-cinnamoyl-2-methoxypiperidine(1)and(R)-1-(2-oxopyrrolidin-3-yl)-5,6-dihydropyridin-2(1H)-one(2),four new amide glucosides,retrofractosides A-D(3-6),and two new phenylpropanoid glucosides,retrofractosides E(7)and F(8),together with 24 known compounds(9-32)were isolated from the fruits of Piper retrofractum.The chemical structures of these new compounds were elucidated based on extensive spectroscopic analysis.All of these isolates(1-32)were evaluated for inhibitory activity against mouse platelet aggregation induced by the peptide AYPGKF-NH2.(E)-N-(Tetrahydro-2H-pyran-2-yl)cinnamamide(9)showed a weak inhibitory efect,with an inhibition ratio of 52.0%at a concentration of 150μM.
基金This project is financially supported by Hi-tech Research and Development Program(2003AA33g-030)the National Natural Science Foundation of China(Contract grant number:50143013).
文摘A novel aromatic diamine, 1, 2-dihydro-2-(4-aminophenyl)-4-[3-methoxy-4-(4-aminophenoxy)]-2, 3-phthalazin-l-one (OO-DA) containing aza heterocyclic structure was synthesized from the bisphenol-like monomer in two steps and used for preparing new aromatic polyamides with high inherent viscosity of 0.89-1.03 dL.g^-1. The structures of diamine and polymers obtained were confirmed by MS, PT-IR, WAXD and ^1H-NMR. The synthesized polymers exhibited high glass transition temperature in the range of 281-307℃ and good solubility in polar solvents.
文摘A convenient method for preparing unsaturated amides via telluro- nium salts employing solid potassium carbonate as a base with high stereo- selectivity in excellent yields has been developed.
文摘Developing mild and efficient catalytic methods for the selective synthesis of amines is a longstanding research objective.In this respect,catalytic deoxygenative amide reduction has proven to be promising but challenging,as this approach necessitates selective C-O bond cleavage.Herein,we report the selective hydroboration of primary,secondary,and tertiary amides at room temperature catalyzed by an earth-abundant-metal catalyst,Zr-H,for accessing diverse amines.Various readily reducible functional groups,such as esters,alkynes,and alkenes,were well tolerated.Furthermore,the methodology was extended to the synthesis of bio-and drug-derived amines.Detailed mechanistic studies revealed a reaction pathway entailing aldehyde and amido complex formation via an unusual C-N bond cleavage-reformation process,followed by C-O bond cleavage.
基金the financial support from the National Natural Science Foundation of China(21991104)the Shandong Province Major Science and Technology Innovation Project(2019JZZY020401)。
文摘The methanolysis of amides,which is widely employed in the synthetic organic chemistry,hardly occurs under mild conditions.To safely and controllably intensify the methanolysis reaction with hightemperature and high-pressure environment,a continuous tubular reaction technology is developed,whose space-time yield is over twice of that of the conventional batch reaction.The methanolysis of acetanilide is selected as the representative reaction,and the influences of temperature,pressure,reactant and catalyst concentration,and residence time on the reaction performances are systematically investigated.Taking the advantages of precise temperature and reaction time control by the tubular reactor,the kinetics of acetanilide methanolysis are determined and compared to the kinetics of acetanilide hydrolysis reaction.The tubular reaction method is also employed to test a variety of other amides to show the effects of substituents,steric hindrance,and alkalinity on the reaction rate of methanolysis.
文摘An interesting reaction procedure for the cross-coupling of potassium styryltrifluoroborates and amides has been developed by using PdCl2(dtbpf)-CuI dual catalyst system. By applying this method, good numbers of amide styrylation products are formed in 85% - 92% yields.
文摘A new robust heterogeneous, versatile, an environmentally benign, eco-friendly, recyclable CuFAP catalyst has been developed for the direct synthesis of nitriles and amides from aldehydes at 100°C for 6 h and 4 h, respectively, under neat reaction condition using hydroxylamine hydrochloride in the presence and the absence of tosyl chloride, respectively. Also the recyclability of catalyst as well as influence of solvents, additives on catalysts performance was investigated. The protocol can be considered as an alternative to conventional method for the synthesis of nitriles and amides in good to excellent yields. A highlight of our protocol is the easy separation of catalyst from reaction mixture, hence the catalyst is reused several times without significant loss of its catalytic activity.
基金financial support from the National Natural Science Foundation of China(Grant Nos.22071188,22371217)Hubei Provincial Natural Science Foundation of China(2023AFA011).
文摘The first asymmetric hydrogenation of acyclic tetrasubstitutedα,β-unsaturated amides has been achieved by using Rh/DuanPhos complex as a catalyst,delivering chiralβ-amino amides with two contiguous chiral centers in excellent yields and high enantioselectivities(up to 99%yield,96%ee),which provides efficient and concise access to valuableβ-amino amide derivatives.The gram-scale reaction and efficient transformation ofβ-amino amide toβ-amino acid andβ-amino cyanide demonstrated the utility of this methodology.
基金the National Natural Science Foundation of China(22101075,U2004189)Central Plains Science and Technology Innovation Leader Project(224200510009)+1 种基金Postdoctoral Research Grant in Henan Province(202103085)Henan Key Laboratory of Organic Functional Molecules and Drug Innovation,and 111 Project(D17007)for financial support.
文摘Herein,we report a condition-controlled divergent synthesis of spiro indene-2,1'-isoindolinones and spiro isochroman-3,1'-isoindolinones through cobalt-catalyzed formal[4+1]and[4+1+1]spirocyclization of aromatic amides with 2-diazo-1H-indene-1,3(2H)-dione.When the reaction is carried out under air in ethyl acetate,spiro indene-2,1'-isoindolinones are formed through Co(II)-catalyzed C—H/N—H[4+1]spirocyclization.When the reaction is run under O2 in CH3CN,on the other hand,spiro isochroman-3,1'-isoindolinones are generated through Baeyer-Villiger oxidation of the in situ formed spiro indene-2,1'-isoindolinones with O2 as a cheaper and environmental-friendly oxygen source.In general,these protocols have advantages such as using non-precious and earth-abundant metal catalyst,no extra additive,high efficiency and regioselectivity.A gram-scale synthesis and the removal of the directing group further highlight its utility.
基金the financial support from the National Natural Science Foundation of China(NSFC,Nos.22171042,21831002,and 22193012)the Jilin Province Natural Science Foundation(No.20160520140JH)+1 种基金the Fundamental Research Funds for the Central Universitiesthe Ten Thousand Talents Program for generous financial support。
文摘Catalytic Michael addition reaction represents a fundamental importance in organic synthetic chemistry.Whereas corresponding conversions toward intrinsically low reactive enamide remains an ongoing challenging.We herein report a copper-catalyzed conjugate addition of allenes toβ-substituted alkenyl amides,one of the most challenging Michael acceptors.The present method utilizes readily available allenes as the latent carbon-based nucleophiles and simple,commonβ-substituted alkenyl amides as starting materials,unlike previous methods that usually preinstall an activating group to improve the reactivity of amide or uses highly reactive stoichiometric quantities of organometallics.Hence,this approach shows good functional group compatibility and can be implemented under mild reaction conditions with excellent level of chemo-and regioselectivities.
基金the National Natural Science Foundation of China(grant no.22271251)the Fundamental Research Funds for the Central Universities(grant nos.226-2023-00016,226-2023-00115,and 226-2022-00224).
文摘In sharp contrast to the well researched and well developed aminocarbonylation of alkenes,the dearomative carbamoylation of abundant areneπ-systems has scarcely been studied despite its great potential to enrich the diversity-oriented synthesis of high-value amides.The formidable challenges associated with such dearomatization include the low reactivity of stable aromaticπ-systems and intricate selectivity issues.Herein,we disclose a general approach toward highly selective dearomative carbamoylations of areneπ-bonds under CO-gas-free conditions.Its extraordinary versatility was demonstrated by tolerating a broad range of nucleophilic partners with high yields and excellent selectivities,thus providing modular access to the divergent synthesis ofβ-functionalized primary amides.In addition,diverse downstream derivatizations including a formal C–H 1,2-olefination/carbamoylation reaction were conducted,exhibiting great potential in synthetic and medicinal chemistry.
基金supported by the National Natural Science Foundation of China(No.21372176)Tongji University 985 Phase Ⅲ funds+1 种基金Pujiang Project of Shanghai Science and Technology Commission(No.11 J1409800)the Program for Professor of Special Appointment(Eastern Scholar) at Shanghai Institutions of Higher Learning
文摘A highly efficient copper-catalyzed approach to form amide bonds from formamides and carboxylic acids was developed. This protocol shows broad substrate scopes and high yields in the presence of 1 mol% catalyst and 4.0 equiv, formamides.
文摘Background Gastric cancer (GC) is one of the most common types of cancer in the world. A change in the metabolism of lipids in tumor cells could lead to the pathogenesis of cancer. In this study, we investigated fatty acid and fatty acid amide metabolic perturbations associated with GC morbidity.
基金supported by the National Natural Science Foundation of China(21332007)Xiamen University
文摘The direct partial reduction of highly stable secondary amides to more reactive aldimines and aldehydes is a challenging yet highly demanding transformation. In this context, only three methods have been reported. We report herein an improved version of the Charette's method. Our protocol consists of activation of secondary amides with triflic anhydride/2-fluoropyridine,and partial reduction of the resulting intermediates with 1,1,3,3-tetramethyldisiloxane(TMDS), which delivered aldimines or aldehydes upon acidic hydrolysis. Aromatic amides were reduced to the corresponding aldimines in 85%–100% NMR yields,and yields(NMR) from aliphatic amides were 72%–86%. Acidic hydrolysis of the aldimine intermediates afforded, in one-pot,the corresponding aldehydes in 80%–96% yields. A simple protocol was established to isolate labile aldimines in pure form in92%–96% yields. The improved method gave generally higher yields as compared to the known ones, and features the use of cheaper and more atom-economical TMDS as a chemoselective reducing agent. In addition, a convenient extraction protocol has been established to allow the isolation of amines, which constitutes a mild method for the N-deacylation of amides, another highly desirable transformation. The extended method retains the advantages of the original method of Charette in terms of mild conditions, good functional group tolerance, and excellent chemoselectivity.