All solvents were freshly distilled before use 合成的产物要说明具体合成方法 y-Benzylglutamate was prepared by the method of Gutmann and Boissinnas (101 was synthesized according to Ref. [4] were synthesized according to published procedures [1 Trimethylene carbonate was synthesized following a procedure described elsewhere. The product was recrystallized twice from diethyl ether. White crystal was obtained in 55% yield: mp 45C). The H-NMR spectrum(4H, 4.50 ppm; 2H, 2.21 ppm) was consistent with that reported previously. 25 Novozym-435(2.0 g)was suspended in 25 mL of nanopure water in a 100 mL round-bottomed flask fitted with a water cooled condenser. The lipase suspension was refluxed for 14 h. The suspension was then allowed to cool to room temperature, and water was removed by freeze drying.. The reaction vials were capped tightly and shaken vigorously for a few minutes. The reaction vials were then placed in a constant-temperature water bath maintained at 37C for 3 h with magnetic stirrin Pentaerythritol (50.0 g, 0.36 mol) and p-toluene-sulfonic acid monohydrate(0.61 g)were dissolved in 500 mL of N, N-dimethylformamide at about 80C, and then the mixture was allowed to cool undisturbed. When the solution cooled to about 40oC. stirring was starte and 55.4 mL of 2, 2-dimethoxypropane(0. 36 mol) was added. After stirring for 24 h at room temperature, the solution was stirred at room temperature with 9.0 g of based-treated DOWEX lXZ-100 ion exchange resin for I h and filtered, and then the solvent was evaporated under reduced pressure below 85C... After the treatment with this resin, the dry product was ground and extracted, first with light petroleum ether(bp 40-60C) for 6 h and then with diethyl ether for 12 h, collected and dried. Yield: 40.0 g, white crystals(61.9 of theory); mp 124.5-125.5°C.H-NMR(300MHz, DMSO-d6):1.28ppm(s,6H), Synthesis of Cyclic Carbonate Monomer<小标题> Triethylamine (84.0 g, 0.825 mol) was added dropwise to a solution of 1,3-propanediol (29.9 g, 0.393 mol) and ethyl chloroformate (85.4 g, 0.786 mol) in 2L of THF at0C over a period 30 min. The reaction mixture was stirred for 2h at room temperature. Precipitated triethylamine hydrochloride salt was filtered off, and the filtrate was concentrated under vacuum. The residue was recrystallized three times from THF-ether 1000 g of glycolic acid was placed in a three necked flask fitted with a stirrer, distillation head and condenser, a thermalmeter for monitoring the temperature of the melt, and a nitrogen bleed. I g of Sb2O3 was added and the vessel was heated to 120C. Polycondensation began and as the rate of water elimination fell, the temperature was increased to 180C and8 All solvents were freshly distilled before use. 合成的产物要说明具体合成方法 -Benzylglutamate was prepared by the method of Gutmann and Boissinnas [10]. …was synthesized according to Ref. [4]. …were synthesized according to published procedures [1]. Trimethylene carbonate was synthesized following a procedure described elsewhere.25 The product was recrystallized twice from diethyl ether. White crystal was obtained in 55% yield: mp 45°C). The 1 H-NMR spectrum (4H, 4.50 ppm; 2H, 2.21 ppm) was consistent with that reported previously. 25 Novozym-435 (2.0 g) was suspended in 25 mL of nanopure water in a 100 mL round-bottomed flask fitted with a water cooled condenser. The lipase suspension was refluxed for 14 h. The suspension was then allowed to cool to room temperature, and water was removed by freeze drying…. The reaction vials were capped tightly and shaken vigorously for a few minutes. The reaction vials were then placed in a constant-temperature water bath maintained at 37 °C for 3 h with magnetic stirring…. Pentaerythritol (50.0 g, 0.36 mol) and p-toluene-sulfonic acid monohydrate (0.61 g) were dissolved in 500 mL of N, N-dimethylformamide at about 80 °C, and then the mixture was allowed to cool undisturbed. When the solution cooled to about 40 °C, stirring was started and 55.4 mL of 2,2-dimethoxypropane (0.36 mol) was added. After stirring for 24 h at room temperature, the solution was stirred at room temperature with 9.0 g of based-treated DOWEX 1XZ-100 ion exchange resin for 1 h and filtered, and then the solvent was evaporated under reduced pressure below 85 °C. …After the treatment with this resin, the dry product was ground and extracted, first with light petroleum ether (bp 40-60 °C) for 6 h and then with diethyl ether for 12 h, collected and dried. Yield: 40.0 g, white crystals (61.9 % of theory); mp 124.5-125.5 °C. 1 H-NMR (300 MHz, DMSO-d6): 1.28 ppm (s, 6H), … Synthesis of Cyclic Carbonate Monomer <小标题> Triethylamine (84.0 g, 0.825 mol) was added dropwise to a solution of 1,3-propanediol (29.9 g, 0.393 mol) and ethyl chloroformate (85.4 g, 0.786 mol) in 2L of THF at 0 °C over a period 30 min. The reaction mixture was stirred for 2h at room temperature. Precipitated triethylamine hydrochloride salt was filtered off, and the filtrate was concentrated under vacuum. The residue was recrystallized three times from THF-ether. 1000 g of glycolic acid was placed in a three necked flask fitted with a stirrer, distillation head and condenser, a thermalmeter for monitoring the temperature of the melt, and a nitrogen bleed. 1 g of Sb2O3 was added and the vessel was heated to 120 °C. Polycondensation began and as the rate of water elimination fell, the temperature was increased to 180 °C and