Hyperpolarization of Amino Acids in Water Utilizing Parahydrogen on a Rhodium Nanocatalyst
作者:Lukas Kaltschnee、Anil P. Jagtap、Jeffrey McCormick、Shawn Wagner、Louis‐S. Bouchard、Marcel Utz、Christian Griesinger、Stefan Glöggler
DOI:10.1002/chem.201902878
日期:2019.8.22
spectroscopies main drawbacks is low sensitivity. Hyperpolarization techniques enhance NMR signals by more than four orders of magnitude allowing the design of new contrastagents. Parahydrogen induced polarization that utilizes the para-hydrogen's singlet state to create enhanced signals is of particular interest since it allows to produce molecular imaging agents within seconds. Herein, we present
Determination of the mutual orientation of the 15N and 13C NMR chemical shift tensors of 13-15N double labeled model peptides for silk fibroin from the dipolar-coupled powder patterns
C]Gly[ 15 N]AlaGlyAla-OPac and Boc-[1- 13 C]Gly[ 15 N]ValGlyAla-OPac, where Boc is t-butoxycarbonyl, OMe is methyl ester, OPac is phenacyl ester, Ala is alanine, Gly is glycine and Val is valine. From the comparisons of the 15 N chemicalshifttensors and the orientations of the principal axis system relative to the molecular symmetry axes among three compounds having [1- 13 C]Ala[ 15 N]Gly units, it
The anti-epileptic agent remacemide hydrochloride has been prepared labelled with 14C, from [carbonyl-14C]acetophenone, and with 13C from [13C6]benzene, [1,2-13C]acetyl chloride and [1-13C]glycine. [2-3H]Glycine was utilised to prepare remacemide labelled with tritium at low specific activity. In addition other 2H- and high specific activity 3H-isotopomers of the drug, and of an active metabolite of
The biosynthesis of pyrrocidines was investigated using a double (18O,13C) labelling of l-tyrosine. It shows that the phenolic 18O is incorporated during aryl ether bond formation.
Boc-derivatives of the six 13C-labelled glycines with or without 15N have been prepared by a direct approach from the corresponding bromoacetates and three of them converted into 15N-labelled amides by an efficient procedure to give isotopomers with 2–4 adjacent 13C and 15N nuclei; their coupling constants have been recorded.