Synthesis and Enzymatic Degradation of Dendrimers from (R)‐3‐Hydroxybutanoic Acid and Trimesic Acid

Abstract

The coupling of 6 with the desilylated branches 7 and 10 finally gave the dendrimers of the first (green circle in formula 11/12) and of the second generation (ll), respectively. The selective hydrogenolysis of the terminal benzyl groups of the dendrimers was achieved by catalytic transfer hydrogenation[61 and gave the polyanionic dendrimers of the first and second generation (12a).The dendritic compounds were obtained in To study the biodegradability['' of the dendrimers, we tested their stability in the presence of various hydrolases. ' 0 x o t + n depicts the degradation of three dendritic compounds 6a, 6b, and llb with a PHB-depolymerase.[81 The linear tetrameric HB 2b was used as the standard substrate for the depolymerase. The protected dendrimers with dimeric HB-elongation units were not degraded by the depolymerase. whereas the free acids were moderately good substrates for this enzyme.['] This observation is surprising as the simple dimeric H B 2a is not a substrate for the depolymerase. 'H N M R spectroscopic investigations of the degradation products of the deprotected, first-generation dendrimer with dimeric HB-elongation units (green circle in formula 11/12) revealed free HB, the triester of 1.3,Sbenzenetricarboxylic acid with HB, and also compound 13.['01 The enzymatic hydrolysis of the deprotected, first-generation dendrimer, which has dimeric HB-elongation units, was followed by ti-

Synthesis of Spacer-Armed Glucodendrimers Based on the Modification of Poly(propylene Imine) Dendrimers

“…Analogous results have been obtained by Seebach et al [27] when studying the enzymatic hydrolysis of a series of dendrimers incorporating ester bonds susceptible to the action of enzymes: enzyme-catalyzed hydrolysis was only possible in the case of the lower generation dendrimers.…”

MALDI-TOF mass spectrometry in the analysis of synthetic polymers

“…of carbosiloxane dendrimers is described by Sheiko et al [104]. Seebach et al [105] use the method for the identification of dendrimers from (R)-3-hydroxybutanoic acid and trimesic acid.…”

The Therapeutic Potential of Microencapsulate Implants: Patents and Clinical Trials

“…Most dendrimers reported so far have been constructed as a branched skeleton that incorporates functional molecules both covalently or noncovalently. Biologically active substances that are attached to the termini of dendritic structures [16] can be liberated by chemical or biological methods [17]. Several branched constructs have been reported to contain covalently linked doxorubicin molecules as end groups [18][19][20].…”