Total synthesis of nstx-3, spider toxin of nephila maculata
摘要:
A spider toxin NSTX-3 obtained from the venom of Papua New Guinean spider, Nephila maculata was synthesized in order to confirm its proposed structure and to supply the sample for the biological tests. The structure of NSTX-3 is now established as 2,4-dihydroxyphenylacetyl-L-Asn-->Cad<--Pua<--L-Arg, where Cad stands for cadaverine and Pua for putreanine.
linking guanidine moiety and core, and modification of the guanidine mimetic. These efforts led to the identification of novel alpha(V)beta(3) inhibitors displaying potency in the subnanomolar range, selectivity versus alpha(IIb)beta(3) and functional efficacy in relevant cellular assays. A method for the preparation of enantiomericallypure derivatives was developed, and respective enantiomers evaluated
The discovery of allyltyrosine based tripeptides as selective inhibitors of the HIV-1 integrase strand-transfer reaction
作者:Neal Dalton、Christopher P. Gordon、Timothy P. Boyle、Nicholas Vandegraaf、John Deadman、David I. Rhodes、Jonathan A. Coates、Stephen G. Pyne、Paul A. Keller、John B. Bremner
DOI:10.1039/c6ob00950f
日期:——
amino acids. Resulting SAR analysis revealed the allyltyrosine residue was a key feature for IN inhibitory activity whilst incorporation of a lysineresidue and extended hydrophilic chains bearing a terminal methyl ester was advantageous. Addition of hydrophobic aromatic moieties to the N-terminal of the scaffold afforded compounds with improved inhibitory activity. Consolidation of these functionalities
multimolecular crowding conditions of live cells is highly desirable for the analysis and engineering of proteins without using genetic manipulation. N‐Sulfonyl pyridone (SP) is reported as a new reactive group for protein sulfonylation. The ligand‐directed SP chemistry was able to modify not only purified proteins in vitro, but also endogenous ones on the surface of and inside live cells selectively and rapidly
The invention relates to novel compounds which bind to integrin receptors, their use as ligands of integrin receptors, in particular as ligands of the &agr;
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integrin receptor, their use, and pharmaceutical preparations comprising these compounds.
Caged enzymes whose activities can be controlled by light represent a powerful tool for various biological analyses. However, limited methods are available for the construction of caged proteins and enzymes. We recently developed a novel protein labeling method termed ligand-directed acyl imidazole (LDAI) chemistry, which allows us to selectively modify natural dihydrofolate reductase and folate receptor in a test tube and in live cell contexts. In this work, we have examined in detail the reaction characteristics of the LDAI chemistry using carbonic anhydrase I (CAI) as a model enzyme. In addition to modifying Lys residues with a carbamate bond, the LDAI method modified Ser and Tyr residues with a carbonate bond. Owing to the relatively labile carbonate bond formed, the LDAI chemistry was demonstrated to be applicable for a rational one-step construction of caged enzymes. This method is simple and based on the transient tethering of an inhibitor with moderate activity that is directed to the active site on an enzyme surface. We successfully showed that the activity of the caged CAI was almost completely suppressed by LDAI-based labeling and fully recovered by photoirradiation in the crude conditions (such as cell lysates) as well as in test tube settings.
笼状酶的活性可受光控制,是进行各种生物分析的有力工具。然而,目前用于构建笼式蛋白质和酶的方法有限。我们最近开发了一种新的蛋白质标记方法,称为配体定向酰基咪唑(LDAI)化学,它使我们能够在试管和活细胞环境中选择性地修饰天然二氢叶酸还原酶和叶酸受体。在这项工作中,我们以碳酸酐酶 I(CAI)为模型酶,详细研究了 LDAI 化学的反应特性。除了用氨基甲酸酯键修饰 Lys 残基外,LDAI 方法还用碳酸键修饰 Ser 和 Tyr 残基。由于形成的碳酸键相对易变,LDAI 化学方法被证明适用于一步构建笼状酶。这种方法非常简单,其基础是将具有中等活性的抑制剂瞬时拴系在酶表面的活性位点上。我们成功地证明,基于 LDAI 的标记几乎完全抑制了笼状 CAI 的活性,而在粗略条件下(如细胞裂解液)和试管环境中,光照射则可完全恢复其活性。