BOC-D-GLU-OH

White to light yellow solid

Add three bottles, into which DMF / H2O (volume ratio of 3: 2) mixed solvent 1.55 liters, stirring state, slowly adding to the system of D-glutamic acid 142 grams, stirring 10 minutes to clarify the system, The system was kept at 20 ° C to 30 ° C and 161 g of di-tert-butyl dicarbonate was added dropwise and stirred for 1 hour. 55The reaction mixture was washed with 200 ml of ethyl acetate, and the organic phase was combined with 200 ml of ethyl acetate. The organic phase was extracted with 200 ml of ethyl acetate, The organic phase was washed with 300 ml of water and then with 300 ml of saturated brine. The organic phase was separated and dried over anhydrous sodium sulfate for 1 hour. The filtrate was dried to give (R) -2- (tert-butoxycarbonyl) Diacid, weighing 157 grams, 90percent yield.General procedure: To a stirredsolution of DCC (9.2 g, 44 mmol), DIPEA (10.5 mL, 80 mmol)and NHS (5.1 g, 44 mmol) in dry DCM (30 mL) at 0 C undernitrogen atmosphere, was added N-Boc protected L-glutamic acid (5 g, 20 mmol). After stirring for 30 min the solution of chiral aminoalcohol 16 (5 g, 20 mmol) in 15 mL DCM wasadded drop-wise viasyringe. The resulting mixture was stirred overnight. After the reaction is completed (TLC), the mixture was filtered through suction filtration. The filtrate is, diluted with DCM (20 mL) and washed with 1 M HCl (3 × 10mL) followed by 5 % NaHCO3(3 × 10 mL) and brine (1 × 15mL), dried over anhydrous MgSO4 and concentrated in vacuo.The crude residues were purified by column chromatographyto afford compound 17 (6.5 g, 85 %) as a white solid.General procedure: To a stirredsolution of DCC (9.2 g, 44 mmol), DIPEA (10.5 mL, 80 mmol)and NHS (5.1 g, 44 mmol) in dry DCM (30 mL) at 0 C undernitrogen atmosphere, was added N-Boc protected L-glutamic acid (5 g, 20 mmol). After stirring for 30 min the solution of chiral aminoalcohol 16 (5 g, 20 mmol) in 15 mL DCM wasadded drop-wise viasyringe. The resulting mixture was stirred overnight. After the reaction is completed (TLC), the mixture was filtered through suction filtration. The filtrate is, diluted with DCM (20 mL) and washed with 1 M HCl (3 × 10mL) followed by 5 % NaHCO3(3 × 10 mL) and brine (1 × 15mL), dried over anhydrous MgSO4 and concentrated in vacuo.The crude residues were purified by column chromatographyto afford compound 17 (6.5 g, 85 %) as a white solid.