N-substituted furfurylamines(FAs)are valuable precursors for producing pharmacologically active compounds and polymers.However,enzymatic synthesis of the type of chemicals is still in its infancy.Here we report an imi...N-substituted furfurylamines(FAs)are valuable precursors for producing pharmacologically active compounds and polymers.However,enzymatic synthesis of the type of chemicals is still in its infancy.Here we report an imine reductase from Streptomyces albidoflavus(SaIRED)for the reductive amination of biobased furans.A simple,fast and interference-resistant high-throughput screening(HTS)method was developed,based on the coloration reaction of carbonyl compounds with 2,4-dinitrophenylhydrazine.The reductive amination activity of IREDs can be directly indicated by a colorimetric assay.With the reductive amination of furfural with allylamine as the model reaction,SaIRED with the activity of 4.8 U mg^(-1) was subjected to three rounds of protein engineering and screening by this HTS method,affording a high-activity tri-variant I127V/D241A/A242T(named M3,20.2 U mg^(-1)).The variant M3 showed broad substrate scope,and enabled efficient reductive amination of biobased furans with a variety of amines including small aliphatic amines and sterically hindered amines,giving the target FAs in yields up to>99%.In addition,other variants were identified for preparative-scale synthesis of commercially interesting amines such as N-2-(methylsulfonyl)ethyl-FA by the screen method,with isolated yields up to 87%and turnover numbers up to 9700 for enzyme.Gram-scale synthesis of N-allyl-FA,a valuable building block and potential polymer monomer,was implemented at 0.25 mol L^(-1) substrate loading by a whole-cell catalyst incorporating variant M3,with 4.7 g L^(-1) h^(-1) space-time yield and 91%isolated yield.展开更多
We report the highly efficient conversion of readily available biomass-derived polyols with amines to valuable furfurylamines orβ-amino alcohols compounds using ruthenium catalysis.The reaction outcome is readily tun...We report the highly efficient conversion of readily available biomass-derived polyols with amines to valuable furfurylamines orβ-amino alcohols compounds using ruthenium catalysis.The reaction outcome is readily tuned by the simple addition of 4Åmolecular sieves(furfurylamines vs.β-amino alcohols)with high chemo-selectivity.The proposed reaction mechanism involves ruthenium-catalyzed hydrogen borrowing for the reduction of the imine intermediate and C–C bond cleavage of polyols via a retro-aldol process.A series of arylamines was suc-cessfully transformed into the desired products with moderate to good yields.展开更多
A Schiff base ligand（H2CSF,C13H11NO4,1） derived from 3-carboxylsalicylaldehyde and furfurylamine,and its trinuclear complex [Ni3（CSF）2（CH3COO）2（DMF）2（H2O）2]（2） were synthesized.Compound 1 was characterized...A Schiff base ligand（H2CSF,C13H11NO4,1） derived from 3-carboxylsalicylaldehyde and furfurylamine,and its trinuclear complex [Ni3（CSF）2（CH3COO）2（DMF）2（H2O）2]（2） were synthesized.Compound 1 was characterized by elemental analysis,1H NMR,IR,MS and X-ray diffraction analysis.The crystal of 1 belongs to the monoclinic system,space group P21/c with a = 8.472（2）,b = 19.743（5）,c = 7.2300（18） ,β = 110.278（4）°,V = 1134.4（5） 3,Z = 4,Mr = 245.23,Dc = 1.436 g·cm-3,μ = 0.108 mm-1,F（000） = 512,λ = 0.71073 ,the final R = 0.0440 and wR = 0.1199 for 1426 observed reflections（I 2σ（I））.In the crystal of 1,there exist intramolecular hydrogen bonds and weak intermolecular C-H···O hydrogen bonds.Compound 2 was characterized by elemental analysis,IR,TG and X-ray diffraction analysis.The crystal of 2 is of triclinic system,space group P1 with a = 10.1237（17）,b = 10.4086（18）,c = 10.4884（18） ,α = 82.528（2）,β = 67.339（2）,γ = 83.010（2）°,V = 1008.1（3） 3,Z = 1,Mr = 962.87,Dc = 1.586 g·cm-3,μ = 1.463 mm-1,F（000） = 498,λ = 0.71073 ,the final R = 0.0517 and wR = 0.0805 for 2065 observed reflections（I 2σ（I））.The geometry of the trinuclear molecule is centrosymmetric,in which every Ni（Ⅱ） ion is coordinated in a slightly distorted octahedron.The three Ni（Ⅱ） ions are arranged in a straight line.The two CSF2-ions act as NOO tridentate ligands with the phenolate and carboxylate oxygen as bridging atoms.The coordination atoms of CSF2-anions and water molecules are coordinated on the equatorial plane,while the two bridging acetate ions and two DMF are trans-coordinated on the apical sites.展开更多
A chloro-bridged dinuclear copper（H） complex with ligand 2-pyridylme-thylene- furfurylamine has been synthesized and characterized by single-crystal X-ray diffraction, and its inhibitory activity on xanthine oxidase...A chloro-bridged dinuclear copper（H） complex with ligand 2-pyridylme-thylene- furfurylamine has been synthesized and characterized by single-crystal X-ray diffraction, and its inhibitory activity on xanthine oxidase （XO） was also evaluated. It crystallizes in the triclinic system, space group P 1 with a = 8.0441（16）, b = 8.5663（17）, c = 10.060（2）A, α = 77.52（3）, β = 72.04（3）, γ = 70.12（3）°, V = 615.3（2）A^3, Z = 1, Dc = 1.731 g/cm^3, F（000） = 322, the final R = 0.0401 and wR = 0.0934 for 1971 observed reflections with I 〉 2σ（I）. X-ray analysis reveals that the Cu（II） cation is five-coordinated by two N atoms of Schiff base and three Cl anions. The C-H…Cl intermolecular and intramolecular hydrogen bonds connect the molecules to form a three-dimensional network. This copper（II） complex shows more potent inhibitory activity against XO with IC50 = 3.48μM than the standard inhibitor allopurinol.展开更多
The synthesis of primary amines via reductive amination in the presence of NH_(3)and H_(2),as a green and sustainable process,has attracted much attention.In this paper,we prepared series of Ni/SiO_(2)catalysts with d...The synthesis of primary amines via reductive amination in the presence of NH_(3)and H_(2),as a green and sustainable process,has attracted much attention.In this paper,we prepared series of Ni/SiO_(2)catalysts with deposition-precipitation and impregnation methods,and their catalytic performances on the reductive amination of a biomass derived compound of furfural to produce furfurylamine were studied.The catalytic activity and the yield were correlated to the structure and the surface properties of catalysts largely.The Ni/SiO_(2)is of high Lewis acidity and small Ni particle with numerous large Ni flat step surface showed high activity and selectivity,it afforded a reaction rate of 12.8 h^(−1)and a high yield to furfurylamine around 98%.These results are superior to the most non-noble metal catalysts reported so far.Moreover,the reaction route was examined with the unit control reactions of the intermediate.To produce furfurylamine selectively,the most suitable catalyst should have the moderate but not the highest activity in activation of hydrogen and hydrogenation in the reductive amination of furfural.This work provides some useful information for the catalytic reductive amination of aldehydes both in the design of catalyst and the reaction route.展开更多
文摘N-substituted furfurylamines(FAs)are valuable precursors for producing pharmacologically active compounds and polymers.However,enzymatic synthesis of the type of chemicals is still in its infancy.Here we report an imine reductase from Streptomyces albidoflavus(SaIRED)for the reductive amination of biobased furans.A simple,fast and interference-resistant high-throughput screening(HTS)method was developed,based on the coloration reaction of carbonyl compounds with 2,4-dinitrophenylhydrazine.The reductive amination activity of IREDs can be directly indicated by a colorimetric assay.With the reductive amination of furfural with allylamine as the model reaction,SaIRED with the activity of 4.8 U mg^(-1) was subjected to three rounds of protein engineering and screening by this HTS method,affording a high-activity tri-variant I127V/D241A/A242T(named M3,20.2 U mg^(-1)).The variant M3 showed broad substrate scope,and enabled efficient reductive amination of biobased furans with a variety of amines including small aliphatic amines and sterically hindered amines,giving the target FAs in yields up to>99%.In addition,other variants were identified for preparative-scale synthesis of commercially interesting amines such as N-2-(methylsulfonyl)ethyl-FA by the screen method,with isolated yields up to 87%and turnover numbers up to 9700 for enzyme.Gram-scale synthesis of N-allyl-FA,a valuable building block and potential polymer monomer,was implemented at 0.25 mol L^(-1) substrate loading by a whole-cell catalyst incorporating variant M3,with 4.7 g L^(-1) h^(-1) space-time yield and 91%isolated yield.
基金support from the National Natural Science Foundation of China(NSFC,Nos.21633013,22022204).
文摘We report the highly efficient conversion of readily available biomass-derived polyols with amines to valuable furfurylamines orβ-amino alcohols compounds using ruthenium catalysis.The reaction outcome is readily tuned by the simple addition of 4Åmolecular sieves(furfurylamines vs.β-amino alcohols)with high chemo-selectivity.The proposed reaction mechanism involves ruthenium-catalyzed hydrogen borrowing for the reduction of the imine intermediate and C–C bond cleavage of polyols via a retro-aldol process.A series of arylamines was suc-cessfully transformed into the desired products with moderate to good yields.
文摘A Schiff base ligand（H2CSF,C13H11NO4,1） derived from 3-carboxylsalicylaldehyde and furfurylamine,and its trinuclear complex [Ni3（CSF）2（CH3COO）2（DMF）2（H2O）2]（2） were synthesized.Compound 1 was characterized by elemental analysis,1H NMR,IR,MS and X-ray diffraction analysis.The crystal of 1 belongs to the monoclinic system,space group P21/c with a = 8.472（2）,b = 19.743（5）,c = 7.2300（18） ,β = 110.278（4）°,V = 1134.4（5） 3,Z = 4,Mr = 245.23,Dc = 1.436 g·cm-3,μ = 0.108 mm-1,F（000） = 512,λ = 0.71073 ,the final R = 0.0440 and wR = 0.1199 for 1426 observed reflections（I 2σ（I））.In the crystal of 1,there exist intramolecular hydrogen bonds and weak intermolecular C-H···O hydrogen bonds.Compound 2 was characterized by elemental analysis,IR,TG and X-ray diffraction analysis.The crystal of 2 is of triclinic system,space group P1 with a = 10.1237（17）,b = 10.4086（18）,c = 10.4884（18） ,α = 82.528（2）,β = 67.339（2）,γ = 83.010（2）°,V = 1008.1（3） 3,Z = 1,Mr = 962.87,Dc = 1.586 g·cm-3,μ = 1.463 mm-1,F（000） = 498,λ = 0.71073 ,the final R = 0.0517 and wR = 0.0805 for 2065 observed reflections（I 2σ（I））.The geometry of the trinuclear molecule is centrosymmetric,in which every Ni（Ⅱ） ion is coordinated in a slightly distorted octahedron.The three Ni（Ⅱ） ions are arranged in a straight line.The two CSF2-ions act as NOO tridentate ligands with the phenolate and carboxylate oxygen as bridging atoms.The coordination atoms of CSF2-anions and water molecules are coordinated on the equatorial plane,while the two bridging acetate ions and two DMF are trans-coordinated on the apical sites.
基金the National Natural Science Foundation of China (No. 649620)
文摘A chloro-bridged dinuclear copper（H） complex with ligand 2-pyridylme-thylene- furfurylamine has been synthesized and characterized by single-crystal X-ray diffraction, and its inhibitory activity on xanthine oxidase （XO） was also evaluated. It crystallizes in the triclinic system, space group P 1 with a = 8.0441（16）, b = 8.5663（17）, c = 10.060（2）A, α = 77.52（3）, β = 72.04（3）, γ = 70.12（3）°, V = 615.3（2）A^3, Z = 1, Dc = 1.731 g/cm^3, F（000） = 322, the final R = 0.0401 and wR = 0.0934 for 1971 observed reflections with I 〉 2σ（I）. X-ray analysis reveals that the Cu（II） cation is five-coordinated by two N atoms of Schiff base and three Cl anions. The C-H…Cl intermolecular and intramolecular hydrogen bonds connect the molecules to form a three-dimensional network. This copper（II） complex shows more potent inhibitory activity against XO with IC50 = 3.48μM than the standard inhibitor allopurinol.
基金the financial support from the National Natural Science Foundation of China(Nos.22172155 and 22072142)the Youth Innovation Promotion Association CAS(No.2016206).
文摘The synthesis of primary amines via reductive amination in the presence of NH_(3)and H_(2),as a green and sustainable process,has attracted much attention.In this paper,we prepared series of Ni/SiO_(2)catalysts with deposition-precipitation and impregnation methods,and their catalytic performances on the reductive amination of a biomass derived compound of furfural to produce furfurylamine were studied.The catalytic activity and the yield were correlated to the structure and the surface properties of catalysts largely.The Ni/SiO_(2)is of high Lewis acidity and small Ni particle with numerous large Ni flat step surface showed high activity and selectivity,it afforded a reaction rate of 12.8 h^(−1)and a high yield to furfurylamine around 98%.These results are superior to the most non-noble metal catalysts reported so far.Moreover,the reaction route was examined with the unit control reactions of the intermediate.To produce furfurylamine selectively,the most suitable catalyst should have the moderate but not the highest activity in activation of hydrogen and hydrogenation in the reductive amination of furfural.This work provides some useful information for the catalytic reductive amination of aldehydes both in the design of catalyst and the reaction route.
