1st generation dendrimeric antioxidants containing Meldrum's acid moieties as surface groups

Abstract

Free radical-caused oxidative stress can be reduced by various antioxidants. A new and promising type of antioxidants is mono-substituted Meldrum`s acids. Herein first dendritic architectures with 1,3-dioxane-4,6-dione units as surface...

Vanillic and Meldrum’s Acid Containing Antioxidant

“…Although this reaction is relatively straightforward (it can be run even in water [27] and solid-state [28]), when rather complex aldehydes are screened, the reaction is limited by the aldehyde. Firstly, we observed insufficient solubility of compound 13 in some of the reaction conditions for the Knoevenagel condensation with Meldrum's acid (15), which was successful for other similar structures. In a heterogenic system (DMSO, r.t.), the reaction was slow and led to an excess of by-products.…”

“…The next step was the construction of the arylidene compound 14 through the Knoevenagel condensation between the aldehyde intermediate 13 and the Meldrum`s acid (15). Although this reaction is relatively straightforward (it can be run even in water [27] and solid-state [28]), when rather complex aldehydes are screened, the reaction is limited by the aldehyde.…”

“…Contrary, decoration of 4-hydroxyquinolin-2(1H)-one with vanillin or syringaldehyde led to compound 3 with slightly increased activity [13]. On the other hand, when 1,3-dioxane-4,6-dione was decorated with any arylmethyl moiety, all compounds 4 demonstrated moderate or high antiradical and antioxidant activity [14,15].…”

Antiradical and Antioxidant Activity of Compounds Containing 1,3-Dicarbonyl Moiety: An Overview

“…Some dendritic architectures 63 containing arylmethyl Meldrum's acid moieties as surface groups have also been studied. Among them, the derivatives with a flexible glycerol core were determined to be a promising scaffold for elaborating powerful antioxidants [180]. The role of C-centered radicals was proven via trapping the radicals with DPPH with di-substituted Meldrum's acid 65 [179].…”

Synthesis and Activity of Ionic Antioxidant-Functionalized PAMAMs and PPIs Dendrimers

“…Carbosilane, when functionalized by polyphenols, also presents antioxidant, antibacterial and anticancer properties [21,22]. The decoration of PAMAM [23][24][25], glycodendrimers [26] or original dendrimers (triazole-bridged, hyperbranched polyurethanes, with an enone or anthraquinone or melamine core) [27][28][29][30][31][32]; these are partnered with specific entities, such as polyphenols, Meldrum's acid derivatives, carbazole, fluorescein or Rhodamine that have also led to new dendritic molecules presenting, among others, good antioxidant properties. Decorated peptide dendrimers have also presented excellent antioxidant properties [33], as well as original radical dendrimers [34].…”