Synthesis of a photo-caged aminooxy alkane thiol

Abstract

A photo-caged aminooxyalkanethiol synthesized in 7 steps and 15% overall yield was used to form a self-assembled monolayer (SAM). Photo-deprotection on the surface was confirmed by FT-IR spectroscopy and contact angle goniometry. Conjugation of a small molecule ketone, ethyl levulinate, further confirmed the presence of aminooxy groups on the surface.

Tunable Aminooxy‐Functionalized Monolayer‐Protected Gold Clusters for Nonpolar and Aqueous Oximation Reactions

“…All efforts to directly incorporate the AOT ligand during Au MPC formation uniformly failed due to problems with aggregation and cluster precipitation, likely due to the strong interparticle hydrogen bonding that increases as AOT loading increases. Indeed, this challenge is evident from examination of the literature, which indicates that aminooxy‐containing ligands are widely incorporated as aminooxy‐protected ligands followed by deprotection of the resultant functionalized surfaces to reveal the aminooxy groups . We were gratified to discover that a ligand place exchange reaction smoothly incorporates AOT to deliver aminooxy‐functionalized Au MMPCs with less hydrogen bonding interactions, which lead to stable and soluble clusters.…”

“…Thygesen et al developed a bifunctional thiol–aminooxy oligo(ethylene glycol) ligand for preparation of aminooxy‐conjugated gold glycanoparticles . Maynard and co‐workers synthesized a photocaged aminooxy alkane thiol for conjugating carbonyl substrates to gold surfaces following photolysis . Given the rapidly growing interests in using gold monolayer‐protected clusters (Au MPCs) and Au NPs for applications in catalysis, sensing volatile organic compounds, analyzing small molecule mixtures using NP‐mediated Raman and laser desorption/ionization spectroscopy, and drug delivery, the development of aminooxy‐functionalized thiol ligands to improve ease of carbonyl ligation as well as to provide flexibility in addressing solubility and adduct loading considerations would enable new applications.…”

Genetically Directed Production of Recombinant, Isosteric and Nonhydrolysable Ubiquitin Conjugates

“…We next designed and synthesised a photocaged variant of aminooxy‐ l ‐lysine, 3 (Scheme A). This would allow mild photo‐deprotection of the aminooxy group (Scheme B), as has been demonstrated in live cells with the analogous lysine derivative . Not only would this broaden the scope for forming nonhydrolysable Ub conjugates of recombinant proteins in vitro, but it also paves the way for photoactivated bioorthogonal labelling of proteins in live cells.…”

Spatiotemporal hydrogel biomaterials for regenerative medicine

“…2-(2-nitrophenyl)propoxycarbonyl (NPPOC) is an appropriate photocage for this purpose because its uncaging does not form a carbonyl group that would undergo condensation with the liberated alkoxyamine (Figure 12c). 94,95 DeForest and Tirrell adopted this strategy for the reversible photopatterning of full-length proteins. 96 A hydrogel network containing pendant NPPOC-caged alkoxyamines was created, and proteins were modified with aldehydes through a photocleavable o -NB linkage (Figure 13).…”