58160-95-5Relevant academic research and scientific papers
Carbon-13 Nuclear Magnetic Resonance Studies of Creatine, Creatinine and some of their Analogs
Dietrich, Robert F.,Marletta, Michael A.,Kenyon, George L.
, p. 79 - 88 (1980)
Creatine (N-methyl-N-amidinoglycine), creatinine (1-methyl-2-aminoimidazolin-4-one) and a series of 38 of their close structural analogs have been examined using natural abundance 13C NMR spectroscopy at 25.16 MHz.Both proton-coupled and proton noise-decoupled spectra were recorded.Unequivocal assignments of the carbon resonances could be made in the vast majority of cases.Both 13C NMR chemical shifts and 1J(CH) values can be used to characterize and to differentiate readily between analogs of creatine and analogs of creatinine.For example, the 1J(CH) coupling constants for the α-carbons of the acyclic creatine analogs were all in the 140-142 Hz range, whereas the corresponding coupling constants for the related, cyclized creatinine analogs were all in the 150-152 Hz range.
An Electrochemical Approach to Designer Peptide α-Amides Inspired by α-Amidating Monooxygenase Enzymes
Lin, Yutong,Malins, Lara R.,Malins, Lara R.
supporting information, p. 11811 - 11819 (2021/08/16)
Designer C-terminal peptide amides are accessed in an efficient and epimerization-free approach by pairing an electrochemical oxidative decarboxylation with a tandem hydrolysis/reduction pathway. Resembling Nature's dual enzymatic approach to bioactive primary α-amides, this method delivers secondary and tertiary amides bearing high-value functional motifs, including isotope labels and handles for bioconjugation. The protocol leverages the inherent reactivity of C-terminal carboxylates, is compatible with the vast majority of proteinogenic functional groups, and proceeds in the absence of epimerization, thus addressing major limitations associated with conventional coupling-based approaches. The utility of the method is exemplified through the synthesis of natural product acidiphilamide A via a key diastereoselective reduction, as well as bioactive peptides and associated analogues, including an anti-HIV lead peptide and blockbuster cancer therapeutic leuprolide.
On-resin click-glycoconjugation of peptoids
Norgren, Anna S.,Budke, Carsten,Majer, Zsuzsa,Heggemann, Carolin,Koop, Thomas,Sewald, Norbert
experimental part, p. 488 - 494 (2009/08/16)
Peptoids are unnatural peptide-like oligomers having the side-chain attached to the glycine nitrogen. In order to investigate how such oligomers are affected upon glycoconjugation, a series of glycosylated peptoids has been synthesized. The conjugation be
Click-to-chelate : Design and incorporation of triazole-containing metal-chelating systems into biomolecules of diagnostic and therapeutic interest
Struthers, Harriet,Spingler, Bernhard,Mindt, Thomas L.,Schibli, Roger
experimental part, p. 6173 - 6183 (2009/05/27)
The site-specific conjugation of metal chelating systems to biologically relevant molecules is an important contemporary topic in bioinorganic and bioorganometallic chemistry. In this work, we have used the Cu'-catalyzed cycloaddition of azides and terminal alkynes to synthesise novel ligand systems, in which the 1,2,3-triazole is an integral part of the metal chelating system. A diverse set of bidentate alkyne building blocks with different aliphatic and aromatic backbones and various donor groups were prepared. The bidentate alkynes were reacted with benzyl azide in the presence of a catalytic amount of Cu 1 to form tridentate model ligands. The chelators were reacted with [ReBr3(CO)3]2- to form well-defined and stable complexes with different overall charges, structures and hydrophilicities. In all cases tridentate coordination of the ligands, including through N3 of the 1,2,3-triazole ring, was observed. The ligand systems could also be quantitatively radiolabelled with the precursor [99mTc (H 2O)3(CO)3]+ at low ligand concentrations. Similarly the alkynes were reacted with an azido thymidine derivative to form a series of compounds, which could be radiolabeled in situ to form single products. Subsequent incubation of the neutral and cationic organometallic 99mTc thymidine derivatives with human cytosolic thymidine kinase, a key enzyme in tumour proliferation, revealed that only the neutral compounds maintained substrate activity towards the enzyme. Bioconjugation, radiolabelling and enzymatic reactions were successfully performed in a matter of hours. Thus, click chemistry provides an elegant method for rapidly functionalising a biologically relevant molecule with a variety of efficient metal chelators suitable for (radiolabelling with the M(CO) 3 core (M = 99mTc, Re), to offer new potential for technetium-99m in clinical and preclinical tracer development.
