Esterification reactions on syndiotactic poly(2‐methallyl alcohol). V. Homopolymers of 2‐methallyl‐(L)‐dipeptidates and dipeptides cleaved from them

Abstract

Syndiotactic poly(2‐methallyl alcohol) (sPMA) is esterified with Nα‐protected (L)‐α‐amino acids by the DCC/HOBT method. The resulting polymer is deprotected by HBr/glacial acetic acid. A second Nα‐protected (L)‐α‐amino acid is condensed to the free α‐NH2 of the amino acid already bound to the sPMA by a water‐soluble carbodiimide in mixed aqueous/organic solution. The formed Nα‐protected dipeptide polymers were hydrazinolized to yield the Nα‐protected dipeptide hydrazides. Alternatively, the dipeptidate polymers were Nα‐deprotected and then hydrolyzed by aqueous KOH at pH = 11.0 to yield the deprotected dipeptides. All polymers and the dipeptides were characterized by 1H‐ and 13C‐NMR and the water‐soluble Nα‐deprotected polymers in addition by potentiometry. The synthetic procedures open a path to defined tactic polymers with chiral oligopeptide side chains and, after their cleavage, also to oligopeptides. During synthesis, the oligopeptide is bound to a dissolved polymer chain of relatively extended macroconformation which facilitates both the accessibility and reactivity of the reaction centers as well as the precipitation and filtration after each synthesis step. © 1995 John Wiley & Sons, Inc.

Inulin polysaccharide having pendant amino acids: Synthesis and characterization

“…Covalent bonding of amino acids to polymers in the main chain 16 -22 or in the side chain [23][24][25] are another example of chemical modification of polymers for biomedical use. Because amino acids are naturally occurring compounds, polymers based on amino acids are expected to be nontoxic, biocompatible, and biodegradable.…”