Sequential insertion of three different organometallics into a versatile building block containing a PNA backbone

Abstract

In the view of developing a synthetic route for the controlled insertion of distinct organometallic moieties into peptide nucleic acid (PNA) oligomers, a proof-of-principle study of the chemoselective insertion of three different organometallics into a building block containing both a PNA backbone and an alkyne side-chain is presented in this study.

Preparation, 99mTc-labeling and biodistribution studies of a PNA oligomer containing a new ligand derivative of 2,2′-dipicolylamine

“…Interestingly, the log D o/w value of [ 99m Tc(CO) 3 (Dpa-PNA)] is practically constant in the pH range investigated, indicating that the protonation state of the PNA remained unchanged. All together, these results show that these compounds should be predestined to give rapid blood clearance and preferential renal excretion as recently found for 68 Ga-and 86 Y-labeled L-RNA oligonucleotides [84,85].…”

“…The presence of Dpa-N 3 was notably ascertained by IR spectroscopy with a strong vibration at 2094 cm − 1 corresponding to the azide function. We then employed the so-called "Click Chemistry" synthetic methodology to derivatize the PNA oligomers with the Dpa moiety, as previously undertaken by our group to efficiently attach organometallics to peptides [67], PNA monomers [68,69] and PNA oligomers [69,70]. It must be noted that "Click Chemistry" has been extensively used to attach metal chelating systems to various entities for rabiolabelling purposes [71][72][73][74][75].…”

Metal–Carbon Bonds in Biopolymer Conjugates: Bioorganometallic Nucleic Acid Chemistry

“…55 Recently, the synthesis of monomers with multiple organometallic moieties has also been reported. 56 However, incorporating these monomers into the center of a PNA strand has proved to be more challenging than end functionalization or postsynthetic labeling, presumably as a result of their instability under oligomerization conditions.…”

Synthesis, characterisation and bioimaging of a fluorescent rhenium-containing PNA bioconjugate

“…9 In this work, we capitalize on our recent discoveries to efficiently attach organometallic complexes to peptides and PNA oligomers using the copper(I)-catalysed Huisgen 1,3-dipolar cycloaddition reaction, often referred to as "Click Chemistry". 29,40,[44][45][46][47][48] In order to label the PNA oligomer with Table S1 and Figures S11-12 in the SI for IR spectra and analytical HPL chromatograms). Thermal stability studies.…”