Ring-opening polymerization of an O-carboxyanhydride monomer derived from l-malic acid

Synthesis of Water-Soluble Poly(α-hydroxy acids) from Living Ring-Opening Polymerization of O-Benzyl-l-serine Carboxyanhydrides

“…Pd/C mediated deprotection of polyester side chains is known to be mild enough that does not lead to degradation of polyester backbones even at elevated temperature. 5d After hydrogenolysis, a 50-mer Ser(Bn)-PAHA with an M n value of 11.6 × 10 3 g/mol resulted in a deprotected polymer Ser-PAHA with an M n value of 6.3 × 10 3 g/mol (Figure S7), which is in excellent agreement with the expected M n (5.7 × 10 3 g/mol). To further evaluate whether the catalytic hydrogenolysis condition has deleterious effect on PAHA, we went on to treat the Ser-PAHA for an additional 24 hours in the identical condition used for deprotection.…”

“…Most of the prior work on ROP of OCAs has focused on developing hydrophilic, charged polymers. 2r,5c However, when used in vivo, charged, hydrophilic polymers tend to show non-specific tissue interaction and reduced circulation half-lives. Hydrophilic, non-charged polymers are often more useful materials in drug delivery, exemplified by polyethylene glycol 8 and cyclodextrin-based polymers.…”

“…1a) under conditions similar to those reported by Bourissou and coworkers. 5a DMAP/IB showed remarkable control for the ROP of Ser(Bn)-OCA and gave Ser(Bn)-PAHA with the expected molecular weights (MWs) and very narrow molecular weight distributions (MWDs, around 1.05–1.15) over a broad range of M/I ratios (50–800; Fig. 1a).…”

“…The ROP of Ser(Bn)-OCA likely proceeded via the similar mechanism suggested by Bourissou for the ROP of Lac-OCA. 5a …”

Photo‐responsive amphiphilic poly(α‐hydroxy acids) with pendent o‐nitrobenzyl ester constructed via copper‐catalyzed azide‐alkyne cycloaddition reaction

“…[39][40][41][42][43][44][45][46] Well-controlled poly (α-hydroxy acids) featuring pendant carboxylic acid groups were obtained via ROP of OCAs derived from glutamic acid or malic acid, followed by deprotection of the benzyl ester side groups. [40,41] In 2012, Cheng reported the synthesis of Tyr (alkynyl)-OCA, an OCA bearing alkynyl group derived from tyrosine. [43] A side-chain aminated poly(α-hydroxy acids) was achieved through the ROP of Tyr(alkynyl)-OCA, followed by thiol-yne "click" photochemistry with 2-aminoethanethiol hydrochloride(AET).…”