167498-27-3Relevant academic research and scientific papers
Peptide fragment coupling using a continuous-flow photochemical rearrangement of nitrones
Zhang, Yuan,Blackman, Melissa L.,Leduc, Andrew B.,Jamison, Timothy F.
, p. 4251 - 4255 (2013/05/08)
Go with the flow: A general approach for amide bond formation by way of a continuous-flow photochemical rearrangement of nitrones was described (see scheme). Simple aryl-alkyl amide bonds as well as complex peptide bonds were constructed efficiently with a residence time less than 20minutes. A tetrapeptide was synthesized in this way and the method could be applied to peptide fragment coupling. Copyright
Evaluation of α,β-unsaturated ketone-based probes for papain-family cysteine proteases
Yang, Zhimou,Fonovic, Marko,Verhelst, Steven H.L.,Blum, Galia,Bogyo, Matthew
experimental part, p. 1071 - 1078 (2009/09/25)
The field of activity-based proteomics makes use of small molecule active site probes to monitor distinct subsets of enzymatic proteins. While a number of reactive functional groups have been applied to activity-based probes (ABPs) that target diverse families of proteases, there remains a continual need for further evaluation of new probe scaffolds and reactive functional groups for use in ABPs. In this study we evaluate the utility of the, α,β-unsaturated ketone reactive group for use in ABPs targeting the papain-family of cysteine proteases. We find that this reactive group shows highly selective labeling of cysteine cathepsins in both intact cells and total cell extracts. We observed a variable degree of background labeling that depended on the type of tag and linker used in the probe synthesis. The relative ease of synthesis of this class of compounds provides the potential for further derivatization to generate new families of cysteine protease ABPs with unique specificity and labeling properties.
Structure-based design, synthesis and evaluation of conformationally constrained cysteine protease inhibitors
Scheidt, Karl A.,Roush, William R.,McKerrow, James H.,Selzer, Paul M.,Hansell, Elizabeth,Rosenthal, Philip J.
, p. 2477 - 2494 (2007/10/03)
The inhibition of cysteine proteases is being studied as a strategy to combat parasitic diseases such as Chagas' disease, leishmaniasis, and malaria. Cruzain is the major cysteine protease of Trypanosoma cruzi, the etiologic agent of Chagas' disease. A crystal structure of cruzain, covalently inactivated by fluoromethyl ketone inhibitor 1 (Cbz-Phe-Ala-FMK), was used as a template to design potential inhibitors. Conformationally constrained γ-lactams containing electrophilic aldehyde (12, 17, 18, 25, 26, and 29) or vinyl sulfone (43, 44, and 46) units were synthesized. Constrained lactam 26 had IC50 values of ca. 20nM against the Leishmania major protease and ca. 50nM versus falcipain, an important cysteine protease isolated from Plasmodium falciparum. However, all of the conformationally constrained inhibitors were weak inhibitors of cruzain, compared to unconstrained peptide aldehyde (e.g. 5 ) and vinyl sulfone inhibitors (e.g. 48, which proved to be an excellent inhibitor of cruzain with an apparent second order inhibition rate constant (k(inact)/K(i)) of 634,000s-1M-1). A significant reduction in activity was also observed with acyclic inhibitors 30 and 51 containing α-methyl phenylalanine residues at the P2 position. These data indicate that the pyrrolidinone ring, especially the quarternary center at P2, interferes with the normal substrate binding mode with cruzain, but not with falcipain or the leishmania protease. Copyright (C) 1998 Elsevier Science Ltd.
Synthesis and stereoselective C-C bond-forming reactions of peptide aldehydes
Reetz, Manfred T.,Griebenow, Nils
, p. 335 - 348 (2007/10/03)
The reaction of the activated form of N-protected amino acids 6 and 10 or peptides 14 and 18 with chiral amino alcohols derived from the corresponding α-amino acids affords peptide alcohols which can be oxidized under Swern conditions to produce the corresponding peptide aldehydes 9, 12, 16 and 20. The rational synthesis of diastereomeric di- and tripeptide aldehydes, e.g., (S,S)- or (R,S)-dipeptides as well as (S,S,S)- or (R,S,S)-tripeptides is possible by proper choice of the respective building blocks [(S)- versus (R)-amino acids]. The compounds can be prepared without any undesired α-epimerization. However, the long-term configurational stability depends upon the configuration at the remote stereogenic center, e.g., (R,S)-dipeptide aldehydes epimerize faster than the (S,S) diastereomers. Di- and tripeptide aldehydes 9, 12, 16 and 20 undergo chelation-controlled Grignardtype additions with Me2CuLi that involve little or no undesired α-epimerization. The (S,S)- and (R,S)-dipeptide aldehydes 9 and 12 undergo chelation-controlled pinacol reactions induced by the low-valent vanadium reagent [V2Cl3(THF)6]2[Zn2Cl 6]. The major products in both cases are the corresponding C2-symmetric diols 33 and 36, respectively, which are of interest as potential HIV-protease inhibitors. The degree of stereoselectivity is significantly higher in the case of the (S,S)-dipeptide aldehydes relative to the (R,S) analogs, an observation which can be explained on the basis of three-point binding of the peptides to vanadium. VCH Verlagsgesellschaft mbH, 1996.
