Prodendronic polyamines from stable or labile methacrylates obtained by selective Michael addition onto asymmetric diacrylic compounds

Abstract

A new synthetic strategy for the preparation of methacrylic monomers and polymers carrying acyl β‐amino groups is presented. The approach is based on the Michael addition of aliphatic amines onto asymmetric acrylic/methacrylic compounds, reacting the amine highly selectively with the acrylic unit while leaving the methacrylic moiety unreacted. The corresponding polymers are then obtained by conventional radical polymerization. The use of N,N,N′,N′‐tetraethyldiethylenetriamine (TEDETA) as the secondary amine leads to TEDETA moieties supported on polymeric chains. The new aminopolymers are sensitive to pH and to temperature exhibiting a lower critical solution temperature of between 50 and 90 °C. A further interesting feature of the new approach is that the stability toward hydrolysis of the side β‐amino acyl compounds was found to be dependent on whether an acrylamide or an acrylate is employed as the acrylic group of the asymmetric starting material. The esters exhibit an enhanced sensitivity to hydrolysis, compared to standard aliphatic esters, and decompose releasing a derivative of the amine precursor, within hours or weeks, depending on the pH and temperature conditions. The use of the amides leads to stable polymers when the same experimental conditions are applied. The novel dendronic polyamines have been proven to interact with DNA and to transfect cells with efficiency close to that obtained with polyethyleneimine vectors used as positive controls. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 2297–2305

Dual stimuli-responsive polyamines derived from modifiedN-vinylpyrrolidones through CuAAC click chemistry

“…On the other hand and for a given composition, the higher the pH, the lower is the LCST. This behavior has also been found in similar alkylated tertiary amines and is related to the protonation, which increases the hydrophilia and hinders the polymer–polymer interactions responsible for the phase separation. Selected turbidimetric graphs have been depicted in Figure showing these dependences on composition and pH: the upper graphs show the turbidimetric studies of copolymers with different compositions for a selected pH (8), while the lower graphs show the influence of the pH for a selected composition ( F VPcpx = 0.8).…”

Understanding the regioselectivity of Michael addition reactions to asymmetric divinylic compounds

“…Thus, this synthetic strategy has allowed for the easy preparation of polymethacrylates bearing pendant special groups such as phosphonate, 2,3 hydroxyl, 4 stearyl, 5 or prodendronic amine moieties. 6 The latest example, described by us, reported the successful use of this strategy with an asymmetric acrylamide/methacrylate divinylic compound. Some of these monomers could be prepared in bulk.…”

“…In addition, the formed b-aminoesters exhibit an enhanced sensitivity to hydrolysis, compared to standard aliphatic esters. 6 Very recently, Armes et al have described for the rst time the usefulness of this facile strategy using thiol-type nucleophiles to obtain cysteineor glutathione-containing methacrylates 7 in water and on a multi-gram scale. Besides, our group has also shown the effectiveness of this facile strategy using thiol-type nucleophiles to obtain cysteine-or glutathione-containing methacrylates 7 in water and on a multi-gram scale.…”

Potential of prodendronic polyamines with modulated segmental charge density as novel coating for fast and efficient analysis of peptides and basic proteins by CE and CE‐MS

“…This behavior was different to that observed previously with other synthesized copolymers in which both anodic and cathodic EOF were observed depending on the pH, most probably due to the involvement of both the amine groups of the polymers (positive charge) and the remaining silanol groups onto the silica wall (negative charge). By using poly‐(TEDETAMA) and poly‐(TEDETAMA‐ co ‐HPMA) the measured EOF was anodal when pH was below 8.1, and tends toward zero at higher pHs, which is related to the deprotonation of the amines (as mentioned above, the p K a has been described to be close to 8.5 ). In addition to this general behavior, more detailed comparison between different polymer coatings was carried out at each pH.…”

“…The amine groups belonging to the unit labeled as TEDETAMA (which is common to all four synthesized polymers) will provide cationic character that will depend on the pH, being the p K a of the tertiary aliphatic amines in an interval centered at 8.5 . It is also expected that different molar percentages of HPMA units will provide to the poly‐(TEDETAMA‐ co ‐HPMA) copolymer different behavior due to the extent of the shielding on the electrostatic interactions and the modulation of the charge density, as indicated in Fig.…”