The synthesis of [23,24]-(13)C(2)-labeled bile salts is achieved through a steroidal side chain degradation and isotopic regeneration strategy. Three common bile acids were degraded to the corresponding C(22 )aldehyde by an oxidative decarboxylation followed by ozonolysis. The side chain was subsequently regenerated via a Horner-Emmons reaction using an ylide generated from (13)C(2)-labeled bromoacetic acid. These compounds were used as probes of protein-bile salt interactions using two- and three-dimensional NMR techniques.
[Question from NMRWiki Q&A forum] About paragnetic impurities, inorganic salts, bad workups, etc. and their impact on small-molecule NMR spectra
About paragnetic impurities, inorganic salts, bad workups, etc. and their impact on small-molecule NMR spectra
I sometimes face the challenge of explaining to my organic chemists that, even if no impurity signals are visible in their 1H spectrum, other signs (like FID shape, very poor s/n compared to what could be expected with the sample qty, broad peaks, bad resolution...) indicate that clearly, something is wrong with their sample.
Everybody would agree that it's way much easier to convince an invidual based on concrete facts ("look, here we can see solvent/starting material/side...
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03-31-2011 09:21 PM
[NMR paper] Cell-free synthesis of 15N-labeled proteins for NMR studies.
Cell-free synthesis of 15N-labeled proteins for NMR studies.
Related Articles Cell-free synthesis of 15N-labeled proteins for NMR studies.
IUBMB Life. 2005 Sep;57(9):615-22
Authors: Ozawa K, Dixon NE, Otting G
Modern cell-free in vitro protein synthesis systems present powerful tools for the synthesis of isotope-labeled proteins in high yields. The production of selectively 15 N-labeled proteins from 15 N-labeled amino acids is particularly economic and yields are often sufficient to analyze the proteins very quickly by two-dimensional NMR...
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12-01-2010 06:56 PM
[NMR paper] Synthesis of [3,4-(13)c(2)]-enriched bile salts as NMR probes of protein-ligand inter
Synthesis of -enriched bile salts as NMR probes of protein-ligand interactions.
Related Articles Synthesis of -enriched bile salts as NMR probes of protein-ligand interactions.
J Org Chem. 2002 Sep 20;67(19):6764-71
Authors: Tochtrop GP, DeKoster GT, Cistola DP, Covey DF
Synthetic methodology that allows for incorporation of isotopic carbon at the C-3 and C-4 positions of bile salts is reported. Three -enriched bile salts were synthesized from either deoxycholic or lithocholic acid. The steroid 3alpha-OH group was oxidized and the A-ring was...
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11-24-2010 08:58 PM
[NMR paper] 19F NMR of trifluoroacetyl-labeled cysteine mutants of myoglobin: structural probes o
19F NMR of trifluoroacetyl-labeled cysteine mutants of myoglobin: structural probes of nitric oxide bound to the H93G cavity mutant.
Related Articles 19F NMR of trifluoroacetyl-labeled cysteine mutants of myoglobin: structural probes of nitric oxide bound to the H93G cavity mutant.
Biochemistry. 2001 Jul 24;40(29):8588-96
Authors: Thomas MR, Boxer SG
Nitric oxide (NO) binds to the myoglobin (Mb) cavity mutant, H93G, forming either a 5- or 6-coordinate Fe--NO heme complex. The H93G mutation replaces the proximal histidine of Mb with glycine,...
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11-19-2010 08:44 PM
[NMR paper] Efficient solid-phase synthesis of Vpr from HIV-1 using low quantities of uniformly 1
Efficient solid-phase synthesis of Vpr from HIV-1 using low quantities of uniformly 13C-, 15N-labeled amino acids for NMR structural studies.
Related Articles Efficient solid-phase synthesis of Vpr from HIV-1 using low quantities of uniformly 13C-, 15N-labeled amino acids for NMR structural studies.
J Pept Res. 1999 Nov;54(5):427-35
Authors: Cornille F, Wecker K, Loffet A, Genet R, Roques B
The 96-amino acid protein Vpr functions as a regulator of cellular processes involved in the human immunodeficiency virus, type 1 (HIV-1) life cycle,...
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11-18-2010 08:31 PM
[NMR paper] Efficient enzymatic synthesis of 13C,15N-labeled DNA for NMR studies.
Efficient enzymatic synthesis of 13C,15N-labeled DNA for NMR studies.
Related Articles Efficient enzymatic synthesis of 13C,15N-labeled DNA for NMR studies.
J Biomol NMR. 1997 Oct;10(3):245-53
Authors: Smith DE, Su JY, Jucker FM
The power of heteronuclear NMR spectroscopy to study macromolecules and their complexes has been amply demonstrated over the last decade. The obstacle to routinely applying these techniques to the study of DNA has been the synthesis of 13C,15N-labeled DNA. Here we present a simple and efficient method to generate...
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08-22-2010 05:08 PM
[NMR paper] Synthesis and interaction studies of 13C labeled lactone derivatives with a model pro
Synthesis and interaction studies of 13C labeled lactone derivatives with a model protein using 13C NMR.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--linkinghub.elsevier.com-ihub-images-PubMedLink.gif Related Articles Synthesis and interaction studies of 13C labeled lactone derivatives with a model protein using 13C NMR.
Bioorg Med Chem. 1993 Nov;1(5):389-97
Authors: Franot C, Benezra C, Lepoittevin JP
Two molecules 9 and 14, representatives of two series of electrophilic lactone derivatives, have been synthesized, and labeled with...
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08-22-2010 03:01 AM
[NMR paper] Synthesis of isotope labeled oligonucleotides and their use in an NMR study of a prot
Synthesis of isotope labeled oligonucleotides and their use in an NMR study of a protein-DNA complex.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www.pubmedcentral.nih.gov-corehtml-pmc-pmcgifs-pubmed-pmc.gif Related Articles Synthesis of isotope labeled oligonucleotides and their use in an NMR study of a protein-DNA complex.
Nucleic Acids Res. 1992 Feb 25;20(4):653-7
Authors: Kellenbach ER, Remerowski ML, Eib D, Boelens R, van der Marel GA, van den Elst H, van Boom JH, Kaptein R
The synthesis of an oligonucleotide labeled with 13C...