3303-55-7Relevant articles and documents
Multifunctional ionic liquid-bound polystyrene resin with high loading capacity as support in solid-phase peptide synthesis
Patra, Tanmoy,Karmakar, Sandip,Upadhyayula, Sreedevi
, p. 1531 - 1534 (2017)
Polystyrene resin-bound ionic liquids (PSILs) with high loading capacities were prepared by immobilizing multifunctional ionic liquids (ILs) on modified polystyrene (PS) resin and used in the solid phase peptide synthesis. Introduction of hydrophobic anio
γ-Valerolactone (GVL): An eco-friendly anchoring solvent for solid-phase peptide synthesis
Al Musaimi, Othman,El-Faham, Ayman,Basso, Alessandra,de la Torre, Beatriz G.,Albericio, Fernando
, (2019/08/26)
Due to the hazardous nature of CH2Cl2, regulatory authorities have imposed restrictions to minimize or even stop its use. It has therefore become imperative to identify environmentally benign solvents to replace it. Here we report on a bio derived solvent, γ-valerolactone, for the incorporation of the first amino acid onto p-alkoxybenzyl alcohol resin in solid-phase peptide synthesis. Satisfactory loading values (by a spectrophotometric method) were achieved. Furthermore, racemization and dipeptide formation were also checked and found to be acceptable.
Layer-assembled 3D Bi2WO6 hierarchical architectures by Ti-doping for enhanced visible-light driven photocatalytic and photoelectrochemical performance
Arif, Muhammad,Zhang, Min,Yao, Jiacheng,Yin, Hongfei,Li, Pengfei,Hussain, Ijaz,Liu, Xiaoheng
, p. 878 - 893 (2019/04/17)
Layer-assembled three-dimensional (3D) catalysis gain substantial attention and widespread application in the field of photocatalysis and solar energy conversion. The 3D hierarchical architecture possesses large surface area and plenty reactive sites which contribute highly in catalysis performance. In this work we report a tetrabutyl titanate (TBT) assisted simultaneous approach of layer-assembled single-unit-cell 3D Bi2WO6 hierarchical architecture by Ti-doping. The Ti-doping beside its morphological effect can also generate crystal defects in the crystal lattice of Bi2WO6, resulting in highly enhanced visible-light driven photocatalytic performance towards highly stable refractory pollutants and profound photoelectrochemical ability. Moreover, the crystal defects mediated by Ti-doping can generate abundant oxygen vacancies which remarkably improve the selective adsorption towards different charges pollutants. Furthermore, the Ti-doping beside its great influence on the electron dynamic and band structure can also introduce the redox couples (Ti3+/Ti4+), resulting in significance enhancement in reactive oxygen species during photocatalytic reaction. The present work provides a valid route for constructing simultaneous approach of layer-assembled 3D hierarchical architecture and Ti-substitution in the crystal structure of Bi2WO6 with great improvement in photocatalytic and photoelectrochemical performance.
Microbial enantioselective removal of the N-benzyloxycarbonyl amino protecting group
Maurs, Michele,Acher, Francine,Azerad, Robert
, p. 22 - 26 (2012/10/29)
In order to deprotect N-carbobenzoxy-l-aminoacids (Cbz-AA) and related compounds, a series of microorganisms was selected from soil by enrichment cultures with Cbz-l-Glu as sole nitrogen source. A lyophilized whole-cell preparation of two Arthrobacter sp. strains grown on Cbz-Glu or Cbz-Gly exhibited a high cleavage activity. The conditions of hydrolysis have been optimized and a quantitative enantioselective deprotection of several Cbz-dl-amino acids was obtained, as well as the deprotection of N-carbamoylester derivatives of several synthetic amino compounds. The preparation of Cbz-d-allylglycine and l-allylglycine in high yield and high optical purity is described as an application of this method.
Peptide bond formation by aminolysin-A catalysis: A simple approach to enzymatic synthesis of diverse short oligopeptides and biologically active puromycins
Usuki, Hirokazu,Yamamoto, Yukihiro,Arima, Jiro,Iwabuchi, Masaki,Miyoshi, Shozo,Nitoda, Teruhiko,Hatanaka, Tadashi
, p. 2327 - 2335 (2011/05/02)
A new S9 family aminopeptidase derived from the actinobacterial thermophile Acidothermus cellulolyticus was cloned and engineered into a transaminopeptidase by site-directed mutagenesis of catalytic Ser491 into Cys. The engineered biocatalyst, designated aminolysin-A, can catalyze the formation of peptide bonds to give linear homo-oligopeptides, hetero-dipeptides, and cyclic dipeptides using cost-effective substrates in a one-pot reaction. Aminolysin-A can recognize several C-terminal-modified amino acids, including the l- and d-forms, as acyl donors as well as free amines, including amino acids and puromycin aminonucleoside, as acyl acceptors. The absence of amino acid esters prevents the formation of peptides; therefore, the reaction mechanism involves aminolysis and not a reverse reaction of hydrolysis. The aminolysin system will be a beneficial tool for the preparation of structurally diverse peptide mimetics by a simple approach.
Engineered transaminopeptidase, aminolysin-S for catalysis of peptide bond formation to give linear and cyclic dipeptides by one-pot reaction
Usuki, Hirokazu,Uesugi, Yoshiko,Arima, Jiro,Yamamoto, Yukihiro,Iwabuchi, Masaki,Hatanaka, Tadashi
supporting information; experimental part, p. 580 - 582 (2010/05/01)
Aminopeptidase from Streptomyces thermocyaneoviolaceus NBRC14271 was engineered into transaminopeptidase and used to catalyze an aminolysis reaction to give linear and cyclic dipeptides from cost-effective substrates such as the ester derivatives of amino
DPP4 INHIBITOR AND PHARMACEUTICAL APPLICATION THEREOF
-
Page/Page column 8-9, (2008/06/13)
The present invention provides a Dpp4 inhibitor which comprises a leucine derivative of the following formula (1) or a methionine derivative of the following formula (2): wherein each R1 and R3 represents a hydrogen atom (H) and an L-amino acid residue; R2 represents a hydroxyl group (OH), alkoxy group having 1 to 6 carbon atoms, amino group (NH2), alkylamino group having 1 to 6 carbon atoms, glycine residue, β-alanine residue, L-amino acid (except for proline, alanine and phenylalanine) residue or L-amino-acid amide (except for proline amide, alanine amide and phenylalanine amide) residue; and R4 represents a hydroxyl group (OH), alkoxy group having 1 to 6 carbon atoms, amino group (NH2), alkylamino group having 1 to 6 carbon atoms, glycine residue, β-alanine residue, L-amino acid (except for proline and alanine) residue or L-amino-acid amide (except for proline amide and alanine amide) residue. These derivatives also act as autophagy regulators.
The molecular basis for the selection of captopril cis and trans conformations by angiotensin I converting enzyme
Tzakos, Andreas G.,Naqvi, Nawazish,Comporozos, Konstantinos,Pierattelli, Roberta,Theodorou, Vassiliki,Husain, Ahsan,Gerothanassis, Ioannis P.
, p. 5084 - 5087 (2007/10/03)
Enzyme-inhibitor recognition is considered one of the most fundamental aspects in the area of drug discovery. However, the molecular mechanism of this recognition process (induced fit or prebinding and adaptive selection among multiple conformers) in several cases remains unexplored. In order to shed light toward this step of the recognition process in the case of human angiotensin I converting enzyme (hACE) and its inhibitor captopril, we have established a novel combinatorial approach exploiting solution NMR, flexible docking calculations, mutagenesis, and enzymatic studies. We provide evidence that an equimolar ratio of the cis and trans states of captopril exists in solution and that the enzyme selects only the trans state of the inhibitor that presents architectural and stereoelectronic complementarity with its substrate binding groove.
Convenient solid-phase synthesis of oligopeptides using pentacoordinated phosphoranes with amino acid residue as building blocks
Li, Zhaolong,Fu, Hua,Gong, Hegui,Zhao, Yufen
, p. 170 - 177 (2007/10/03)
The reactive intermediates of pentacoordinated phosphoranes with amino acids (P(5)-AA) as building blocks, which were obtained by the reaction of O-phenylene phosphorochloridate with N,O-bis(trimethylsilyl)amino acids, were linked to a solid-phase support containing a hydroxymethyl polystyrene functional group. The first amino acid residue was coupled to the solid-phase support after washing the resin with organic solvent. Repeating the procedure led to oligopeptides linked on the resin. A series of free oligopeptides including tetra-Gly, di-Val, tri-Val, di-Leu, di-Phe, and Phe-Leu were obtained after cleavage from solid-phase support. The structure of these oligopeptides were determined by IR, 1H NMR, FAB-MS, and HPLC.
Enantioselective Enzymatic Cleavage of N-Benzyloxycarbonyl Groups
Patel, Ramesh N.,Nanduri, Venkata,Brzozowski, David,McNamee, Clyde,Banerjee, Amit
, p. 830 - 834 (2007/10/03)
A new enzymatic process for the enantioselective cleavage of N-benzyloxycarbonyl (Cbz) groups from protected amino acids and related compounds has been developed. The Cbz-deprotecting enzyme was isolated from cell extracts of Sphingomonas paucimobilis SC 16113 and purified to homogeneity. The purified protein has a molecular weight of 155,000 daltons and a subunit size of 44,000 daltons.