A series of novel N-[α-(isoflavone-7-O-)acetyl] amino acid methyl esters were prepared from the efficient and regioselective alkylation of isoflavones with chloroacetyl amino acid derivatives under mild condition.
Ethyl 2,3-diphthalimidoylpropanoate was effectively synthesized from ethyl propynoate with two equivalents of phthalimide catalyzed by triphenylphosphine in good yield. The choice of reaction media was important for s...Ethyl 2,3-diphthalimidoylpropanoate was effectively synthesized from ethyl propynoate with two equivalents of phthalimide catalyzed by triphenylphosphine in good yield. The choice of reaction media was important for selective synthesis of the desired 2,3-diaminocarboxylic acid derivatives. The reaction is considered to occur through a zwitterionic intermediate derived from the reaction of the α,β-unsaturated ester with triphenylphosphine.展开更多
Enantiomers of four amino alcohols were resolved by ion-pair chromatography with (+)-10-camphorsulphonic acid as chiral counter ion. Studies of the influence of the mobile phase composition, the solute structure and t...Enantiomers of four amino alcohols were resolved by ion-pair chromatography with (+)-10-camphorsulphonic acid as chiral counter ion. Studies of the influence of the mobile phase composition, the solute structure and the mobile phase flow-rate on separation are presented. Under the optimized conditions enantiomeric propanolol, norephedrine, metropolol and salbutamol were separated using dichloromethane-1-pentanol (97:3 v/v) as mobile phase on Lichrospher-100-DIOL column.展开更多
Chiral amino acids and their corresponding amino alcohols bearing camphoric backbone were prepared from D-（＋）-camphoric imide and characterized by infrared, elemental analysis, ESI-MS, and NMR measurements. Among t...Chiral amino acids and their corresponding amino alcohols bearing camphoric backbone were prepared from D-（＋）-camphoric imide and characterized by infrared, elemental analysis, ESI-MS, and NMR measurements. Among them, one intermediate （1S,3R）-3-amino-2,2,3- trimethyl cyclopentane-1-carboxylic acid hydrochloride 3 was structurally elucidated by X-ray diffraction techniques. Versatile intermolecular hydrogen bonding interactions observed in its packing structure result in a two-dimensional framework.展开更多
Purpose： This paper introduces an amino acids industry knowledge service platform, which integrates industry data, science literature, and technology knowledge from patents.Design/methodology/approach： From the pers...Purpose： This paper introduces an amino acids industry knowledge service platform, which integrates industry data, science literature, and technology knowledge from patents.Design/methodology/approach： From the perspective of knowledge organization, the amino acids industry knowledge service platform comprises a basic data layer, a knowledge representation layer, and a knowledge service layer. The platform integrates heterogeneous information sources by means of a multi-dimensional integration index. It enables users to find technology knowledge from patents by employing the semantic Theory of Inventive Problem Solving （TRIZ）.Findings： This paper constructs an integrated amino acids industry database, which offers a general service oriented to the public, and a technical innovation knowledge base, which offers a value-added service oriented to enterprises.Research limitations： The technical innovation knowledge base only includes parts of amino acids technology knowledge, making it suitable to meet certain specific needs.Practical implications： Semantic annotation of technical innovation knowledge from patents requires manual work by domain experts.Originality/value： The amino acids industry knowledge service platform offers not only an integrated search service for amino acids industry information, but also a deep tech mining service for technical innovation knowledge of amino acids. It will offer a more personalized knowledge service in the future.展开更多
A novel coordination polymer, namely [Zn2（CAPA）（DMA）（H2O）]2n·n（H2O）（1,H4CAPA = 5-（bis（4-carboxybenzyl） amino） isophthalic acid, DMA = N,N-dimethylacetamide） has been synthesized through a solvotherm...A novel coordination polymer, namely [Zn2（CAPA）（DMA）（H2O）]2n·n（H2O）（1,H4CAPA = 5-（bis（4-carboxybenzyl） amino） isophthalic acid, DMA = N,N-dimethylacetamide） has been synthesized through a solvothermal method and characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectra, and thermogravimetric analyses. The crystal structure is of monoclinic, space group P21/n with a = 8.0585（5）, b = 18.9733（10）, c = 20.2044（14） A^°3, β = 101.144（7）°, V = 3030.9（3） ？~3, C56H54Zn4N4O21, Mr = 1378.58, Z = 2）. The compound forms a three-dimensional（3D） supramolecular framework by linking adjacent layers via hydrogen bonds and π···π interactions. It is interesting that the crystal structure is much related to the flexibility and configuration of the ligand. In addition, the thermal stability and luminescence properties for the compound have also been investigated.展开更多
Domain-based protein-protein interactions( PPIs) is a problem that has drawn the attentions of many researchers in recent years and it has been studied using lots of computational approaches from many different perspe...Domain-based protein-protein interactions( PPIs) is a problem that has drawn the attentions of many researchers in recent years and it has been studied using lots of computational approaches from many different perspectives. Existing domain-based methods to predict PPIs typically infer domain interactions from known interacting sets of proteins. However,these methods are costly and complex to implement. In this paper, a simple and effective prediction model is proposed. In this model,an improved multiinstance learning( MIL) algorithm( MilCaA) is designed that doesn't need to take the domain interactions into consideration to construct MIL bags. Then, the pseudo-amino acid composition( PseAAC) transformation method is used to encode the instances in a multi-instance bag and the principal components analysis( PCA) is also used to reduce the feature dimension. Finally, several traditional machine learning and MIL methods are used to verify the proposed model. Experimental results demonstrate that MilCaA performs better than state-of-the-art techniques including the traditional machine learning methods which are widely used in PPIs prediction.展开更多
Hydrogels formed by gelators have attracted growing attention for their promising application in biomaterials and biotechnology, We describe in this paper the generation and characterization of a novel photo-, thermal...Hydrogels formed by gelators have attracted growing attention for their promising application in biomaterials and biotechnology, We describe in this paper the generation and characterization of a novel photo-, thermal- and pH-responsive hydrogel based on an amino acid gelator AA-Azo-EG6. Specifically, the gelator bears an amino acid head, an azobenzene （Azo） linker, and a short oligoethylene glycol tail （EG6）. The resulting AA-Azo-EG6 hydrogel is injectable and exhibits interesting helical self-assembled structures, Meanwhile, the hydrogel is able to experience a gel-sol or gel-precipitate phase transition responding to external stimuli. Thus, this AA-Azo-EG6 gelator is a promising building block for intelligent materials and drug delivery.展开更多
Toll-like receptor 5 （TLR5） signaling in response to flagellin is dispensable for inducing humoral immunity, but alterations of aa 89-96, the TLR5 binding site, significantly reduced the adjuvanticity of flagellin. ...Toll-like receptor 5 （TLR5） signaling in response to flagellin is dispensable for inducing humoral immunity, but alterations of aa 89-96, the TLR5 binding site, significantly reduced the adjuvanticity of flagellin. These observations indicate that the underlying mechanism remains incompletely understood. Here, we found that the native form of Salmonella typhimurium aa 89-96-mutant flagellin extracted from flagella retains some TLR5 recognition activity, indicating that aa 89-96 is the primary, but not the only site that imparts TLR5 activity. Additionally, this mutation impaired the production of IL-lp and IL-18. Using TLR5KO mice, we found that aa 89-96 is critical for the humoral adjuvant effect, but this effect was independent of TLR5 activation triggered by this region of flageUin. In summary, our findings suggest that aa 89-96 of flagellin is not only the crucial site responsible for TLR5 recognition, but is also important for humoral immune adjuvanticity through a TLR5-independent pathway.展开更多
文摘A series of novel N-[α-(isoflavone-7-O-)acetyl] amino acid methyl esters were prepared from the efficient and regioselective alkylation of isoflavones with chloroacetyl amino acid derivatives under mild condition.
文摘Ethyl 2,3-diphthalimidoylpropanoate was effectively synthesized from ethyl propynoate with two equivalents of phthalimide catalyzed by triphenylphosphine in good yield. The choice of reaction media was important for selective synthesis of the desired 2,3-diaminocarboxylic acid derivatives. The reaction is considered to occur through a zwitterionic intermediate derived from the reaction of the α,β-unsaturated ester with triphenylphosphine.
文摘Enantiomers of four amino alcohols were resolved by ion-pair chromatography with (+)-10-camphorsulphonic acid as chiral counter ion. Studies of the influence of the mobile phase composition, the solute structure and the mobile phase flow-rate on separation are presented. Under the optimized conditions enantiomeric propanolol, norephedrine, metropolol and salbutamol were separated using dichloromethane-1-pentanol (97:3 v/v) as mobile phase on Lichrospher-100-DIOL column.
基金This work was funded by the National Natural Science Foundation of China (No. 20301009)
文摘Chiral amino acids and their corresponding amino alcohols bearing camphoric backbone were prepared from D-（＋）-camphoric imide and characterized by infrared, elemental analysis, ESI-MS, and NMR measurements. Among them, one intermediate （1S,3R）-3-amino-2,2,3- trimethyl cyclopentane-1-carboxylic acid hydrochloride 3 was structurally elucidated by X-ray diffraction techniques. Versatile intermolecular hydrogen bonding interactions observed in its packing structure result in a two-dimensional framework.
基金supported by the Chinese Academy of Sciences(Grant No.KFJ-EW-ZY-008)
文摘Purpose： This paper introduces an amino acids industry knowledge service platform, which integrates industry data, science literature, and technology knowledge from patents.Design/methodology/approach： From the perspective of knowledge organization, the amino acids industry knowledge service platform comprises a basic data layer, a knowledge representation layer, and a knowledge service layer. The platform integrates heterogeneous information sources by means of a multi-dimensional integration index. It enables users to find technology knowledge from patents by employing the semantic Theory of Inventive Problem Solving （TRIZ）.Findings： This paper constructs an integrated amino acids industry database, which offers a general service oriented to the public, and a technical innovation knowledge base, which offers a value-added service oriented to enterprises.Research limitations： The technical innovation knowledge base only includes parts of amino acids technology knowledge, making it suitable to meet certain specific needs.Practical implications： Semantic annotation of technical innovation knowledge from patents requires manual work by domain experts.Originality/value： The amino acids industry knowledge service platform offers not only an integrated search service for amino acids industry information, but also a deep tech mining service for technical innovation knowledge of amino acids. It will offer a more personalized knowledge service in the future.
基金supported by the “Strategic Priority Research Program” of the Chinese Academy of Sciences(XDA07070200,XDA09030102)the Science Foundation of Fujian Province(2006l2005)
文摘A novel coordination polymer, namely [Zn2（CAPA）（DMA）（H2O）]2n·n（H2O）（1,H4CAPA = 5-（bis（4-carboxybenzyl） amino） isophthalic acid, DMA = N,N-dimethylacetamide） has been synthesized through a solvothermal method and characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectra, and thermogravimetric analyses. The crystal structure is of monoclinic, space group P21/n with a = 8.0585（5）, b = 18.9733（10）, c = 20.2044（14） A^°3, β = 101.144（7）°, V = 3030.9（3） ？~3, C56H54Zn4N4O21, Mr = 1378.58, Z = 2）. The compound forms a three-dimensional（3D） supramolecular framework by linking adjacent layers via hydrogen bonds and π···π interactions. It is interesting that the crystal structure is much related to the flexibility and configuration of the ligand. In addition, the thermal stability and luminescence properties for the compound have also been investigated.
基金National Natural Science Foundations of China(Nos.61503116,61402007)Foundation for Young Talents in the Colleges of Anhui Province Committee,China(No.2013SQRL097ZD)+1 种基金Natural Science Foundation of Anhui Educational Committee,China(No.KJ2014A198)Natural Science Foundation of Anhui Province,China(No.1408085QF108)
文摘Domain-based protein-protein interactions( PPIs) is a problem that has drawn the attentions of many researchers in recent years and it has been studied using lots of computational approaches from many different perspectives. Existing domain-based methods to predict PPIs typically infer domain interactions from known interacting sets of proteins. However,these methods are costly and complex to implement. In this paper, a simple and effective prediction model is proposed. In this model,an improved multiinstance learning( MIL) algorithm( MilCaA) is designed that doesn't need to take the domain interactions into consideration to construct MIL bags. Then, the pseudo-amino acid composition( PseAAC) transformation method is used to encode the instances in a multi-instance bag and the principal components analysis( PCA) is also used to reduce the feature dimension. Finally, several traditional machine learning and MIL methods are used to verify the proposed model. Experimental results demonstrate that MilCaA performs better than state-of-the-art techniques including the traditional machine learning methods which are widely used in PPIs prediction.
基金supported by [18_TD$IF]State High-Tech Development Program of China (863 Program, No. 2015AA020941)the National Natural Science Foundation of China(Nos. NSFC21474004 and NSFC21434008)the Youth Thousand-Talents Program of China for support
文摘Hydrogels formed by gelators have attracted growing attention for their promising application in biomaterials and biotechnology, We describe in this paper the generation and characterization of a novel photo-, thermal- and pH-responsive hydrogel based on an amino acid gelator AA-Azo-EG6. Specifically, the gelator bears an amino acid head, an azobenzene （Azo） linker, and a short oligoethylene glycol tail （EG6）. The resulting AA-Azo-EG6 hydrogel is injectable and exhibits interesting helical self-assembled structures, Meanwhile, the hydrogel is able to experience a gel-sol or gel-precipitate phase transition responding to external stimuli. Thus, this AA-Azo-EG6 gelator is a promising building block for intelligent materials and drug delivery.
文摘Toll-like receptor 5 （TLR5） signaling in response to flagellin is dispensable for inducing humoral immunity, but alterations of aa 89-96, the TLR5 binding site, significantly reduced the adjuvanticity of flagellin. These observations indicate that the underlying mechanism remains incompletely understood. Here, we found that the native form of Salmonella typhimurium aa 89-96-mutant flagellin extracted from flagella retains some TLR5 recognition activity, indicating that aa 89-96 is the primary, but not the only site that imparts TLR5 activity. Additionally, this mutation impaired the production of IL-lp and IL-18. Using TLR5KO mice, we found that aa 89-96 is critical for the humoral adjuvant effect, but this effect was independent of TLR5 activation triggered by this region of flageUin. In summary, our findings suggest that aa 89-96 of flagellin is not only the crucial site responsible for TLR5 recognition, but is also important for humoral immune adjuvanticity through a TLR5-independent pathway.
