Miyazaki A, Asanuma M, Dodo K, Egami H, Sodeoka M * ERATO, Japan Science and Technology
Agency, Wako and RIKEN Center for Sustainable Resource Science, Wako, Japan
A ‘Catch-and-Release’ Protocol for Alkyne-Tagged Molecules Based on a Resin-Bound
Cobalt Complex for Peptide Enrichment in Aqueous Media.
Chem. Eur. J. 2014;
20: 8116-8128
Key words
alkynes - peptides - Nicholas reaction - solid-phase synthesis - cobalt
Significance
A ‘catch-and-release’ protocol for the enrichment of alkyne-tagged biomolecules using
a resin-supported phosphine cobalt carbonyl complex in aqueous media was developed.
The reaction of a PS-PEG resin (TentaGel) supported cobalt complex 7 with a propargyloxycarbonyl-functionalized peptide 6 (prepared from a dipeptide 1 over four steps) proceeded in 30% EtOH/HEPES buffer solution to give the corresponding
dicobalt alkyne complex 8. The following Nicholas-type reaction–decarboxylation sequence of 8 afforded the free amine 4 in 77% yield.
Comment
The reaction of the alkyne-tagged dipeptide 6 with the solid-supported cobalt complex 7 was performed under high-dilution conditions (50 μM of 6). After the complexation of 6 with 7, the resulting polymeric peptide complex was treated with 5% TFA to release the free
amine 4 as a single product, where an alkyne 6 was not detected in the solution by mass spectrometry.
