反应详情

By a method similar to that of Synthetic Example 4, poly-γ-benzyl-L-glutamic acid was obtained and dissolved in 1,2-dichloroethane. Thereto were added an equivalent amount of norbornane-2-methanol (manufactured by Tokyo Chemical Industry Co., Ltd.) relative to the glutamic acid unit of poly-γ-benzyl-L-glutamic acid and a catalytic amount of p-toluenesulfonic acid monohydrate, and the mixture was stirred at 65° C. for 4 days to give a γ-benzyl-L-glutamic acid/γ-2-norbornylmethyl-L-glutamic acid copolymer. The weight average molecular weight, Mw, of the obtained copolymer was measured by Measurement Method 1 described below. In addition, the composition of the polymer after transesterification reaction was measured by Measurement Method 2 described below.