Patent ID: 6228423
Filing Date: 2001-05-08
Classification: A61K,C08G,Y10S,Y10T

Abstract:
A process for making a biodegradable, biocompatible polymer of the formula: ##STR3##wherein:R.sub.1, R.sub.2 and R.sub.5 are selected independently and are selected from H, linear or branched alkyl groups;R.sub.3 and R.sub.4 are H;R.sub.6 is selected from H, an amine protecting group, a spacer molecule or a biologically active species;X is selected from an O or S group; andX and y are integers such that at least about 95% of the polymer is comprised of .alpha.-hydroxy acid residues, which comprises:forming a mixture of monomers comprising at least one .alpha.-hydroxy acid and at least one .alpha.-amino acid having an amine protecting group with an organic solvent solution of an esterification catalyst under inert atmospheric conditions;copolymerizing said monomers; andisolating the resultant polymer.