Preparation of tris-based dendrimer-grafted core-shell type resin for solid-phase peptide synthesis

Dendrons and dendritic catalysts immobilized on solid support: Synthesis and dendritic effects in catalysis

“…The dendrimer growth involved the attachment of the monomer to a resin-bound primary amine (thus converting the isocyanate into urea) followed by an ester reaction with a propane 1,3-diamine spacer, which formed an amide and restored a primary amine terminus. Contrary to the reports of Chan et al 34 and Lee et al, 35 the synthesis was monitored by both on-resin and cleavage analysis, and this ensured the clean and uniform growth of dendritic wedges. Although the dendrons were constructed on aminomethyl polystyrene or diamine-linker-bearing polystyrene only to the second generation, their triply branched nature and the large size of the starting resin beads resulted in dendronized beads with a terminal group loading as high as 230 nmol/bead.…”

“…In a number of cases, PAMAM dendrons were also prepared from other polymer particle cores. 32,33 Additional polyamidodendrons were prepared by Chan et al 34 and Lee et al 35 Both dendrons were based on a trifurcated branching unit (all the aforementioned dendrons were based on a bifurcated monomer), and as a consequence, each generation multiplied the terminal group loading by a factor of 3. The dendrons were prepared by Chan et al on polystyrene with a nonsymmetric triamino acid; first-and second-generation peptide-like dendrons were prepared, which could effectively be further functionalized (Fig.…”

“…In both cases, the dendrons were not cleaved from the support, but rather the analysis of the terminal groups (e.g., the spectrophotometric determination of Fmoc release from the molecules attached to dendritic termini) was used to deduce the efficiency of dendron growth. Thus, the characterization of the den- 35 HIGHLIGHTdrons was rather limited and did not contain any indication of the dendron homogeneity.…”

Dendritic Molecules on Solid Support: Solid‐Phase Synthesis and Applications

“…The dendrons prepared divergently by Lee and coworkers on TentaGel and PS-co-PEG-NH 2 resins were based on symmetric, TRIS-derived triamino acid monomer and were constructed up to the formal fifth and seventh generations, respectively, using the BOP/HOBt coupling method (Scheme 15.8). 29 Since only the spectrophotometric determination of Fmoc release from the molecules, attached to the dendritic termini, was used to deduce the efficiency of the dendron growth, the characterization of the dendrons was rather limited and no indication as to the dendron homogeneity was provided. Chan and coworkers used a nonsymmetric triamino acid, 4-azalysine, to prepare (via divergent growth) first-and second-generation peptide-like dendrons on polystyrene using Boc-protected monomer and DIC/HOAt (first generation) and HATU (second generation) coupling protocols (Figure 15.5).…”

“…102 The utility and versatility of other polyamide dendron-modified high-loading supports were demonstrated by Chan and coworkers in SPOS of sulfonamides, carboxamides, and other small molecules, 30 as well as by Lee and coworkers in SPOS of pentapeptides. 29 …”