“Click” Chemistry for the Functionalization of Graphene Oxide with Phosphorus Dendrons: Synthesis, Characterization and Preliminary Biological Properties

Abstract

Two families of phosphorhydrazone dendrons having either an azide or an alkyne linked to the core and diverse types of pyridine derivatives as terminal functions have been synthesized and characterized. These dendrons were grafted via click reaction to graphene oxide (GO) functionalized with either alkyne or azide functions, respectively. The resulting modified‐GO and GO‐dendrons materials have been characterized by Fourier Transform Infrared (FTIR), Raman spectroscopy (RS), and Magic Angle Spinning Nuclear Magnetic Resonance (MAS‐NMR) analyses. In addition, the free dendrons and the dendrons grafted to GO were tested toward cancerous (HCT116) and non‐cancerous (RPE1) cell lines.

A water-soluble polyphosphorhydrazone Janus dendrimer built by “click” chemistry as support for Ru-complexes in catalysis

“…Integration of “click” triazole chemistry holds tremendous potential as it could enable the generation of complex dendritic structures using straightforward methodologies. In this context, our research has focused on the synthesis of PPH Janus dendrimers by coupling of AB 5 -type dendrons decorated with azide or acetylene moieties (with similar traits as recently reported by Alami and co-workers 51 ), aiming the formation of a structure coupling a water-soluble modulation PEG-chain on the azide dendron, and an acetylene dendron bearing functional groups to allow the grafting of catalytic moieties.…”

“…It entailed the reaction of 13-[G 0 ′][G 1 ]-PEG with N -methyldichlorothiophosphorhydrazide 9 in the presence of anhydrous Na 2 SO 4 , as previously described for the growing of dendrons. 51 The synthesis of 14-[G 1 ][G 1 ]-PEG was confirmed once more by 31 P{ 1 H} NMR by the emergence of a new set of signals corresponding to the terminal –P(S)Cl 2 group, manifesting as two singlets at 62.5 ppm and 62.7 ppm.…”

“…Verification of the desired products was carried out through 31 P{ 1 H} NMR spectroscopy, revealing the formation of a singlet at 7.4 ppm for the azide derivative 7-[G 0 ′] and the emergence of a multiplet (8.7–6.9 ppm) for the acetylene counterpart 8-[G 0 ′] . 51 The final steps in dendron synthesis were dedicated to the growing of the azide dendron to the first-generation, and the subsequent modification of its surface by incorporating PEG chains to enhance the solubility in water. Firstly, the aldehyde-terminated dendron 7-[G 0 ′] was grown to the first-generation 10-[G 1 ] .…”

Dendritic Pyridine–Imine Copper Complexes as Metallo-Drugs

“…The functions at the core were chosen for their ability to react with functionalized graphene oxide (GO). Dendrons having a Boc-protected amine at the core (dendrons 6a,b,c-G1) were tentatively deprotected to generate a primary amine by the six dendrons was also tested against the HCT116 cell line, but none of them were really active [41]. Two other series of dendrons were synthesized, bearing either an alkyne or an azide at the core.…”

“…Four dendrons (7a-G 1 , 7b-G 1 , 8a-G 1 , and 8b-G 1 ) were active against the HCT116 cell line at a concentration of 10 −5 M but not at 10 −6 M. These four dendrons were then tested with the non-cancerous RPE1 cells and were deceptively found to be even more toxic, as shown in Figure 10. The GO functionalized by the six dendrons was also tested against the HCT116 cell line, but none of them were really active [41].…”