34404-28-9

White to light yellow solid

N-Boc-D-glutamic Acid is an N-Boc-protected form of D-Glutamic acid (G596965). D-Glutamic acid is an unnatural isomer of L-Glutamic acid (G596960), and is found in bacterial cell wall peptidoglycan of gram-positive and gram-negative bacteria. D-Glutamic acid also occurs as poly-gamma-Glutamic acid, which is a weak immunogen but is capable of acting as a hapten (a small molecule that induces the production of antibodies, as well as binding to them).

General procedure for the synthesis of (R)-2-((tert-butoxycarbonyl)amino)glutaric acid from D-glutamic acid and di-tert-butyl dicarbonate: 1.55 liters of a solvent mixture of DMF/H2O (3:2, v/v) was added to a reaction flask and stirring was turned on. Slowly add 142 g of D-glutamic acid to the system and stir for 10 minutes until the system is clarified. Maintaining the temperature of the system between 20°C and 30°C, 161 g of di-tert-butyl dicarbonate was slowly added dropwise, and the reaction was continued with stirring for 1 hour after the dropwise addition. Upon completion of the reaction, the reaction mixture was washed with 200 mL of ethyl acetate and the organic phases were combined. The organic phase was extracted once more with 200 ml of ethyl acetate and subsequently washed sequentially with 300 ml of water and 300 ml of saturated saline. The organic phase was separated and dried with anhydrous sodium sulfate for 1 hour. The drier was removed by filtration and the filtrate was concentrated and dried to give 157 g of (R)-2-((tert-butoxycarbonyl)amino)glutaric acid in 90% yield.

[1] Journal of the American Chemical Society, 2011, vol. 133, # 51, p. 20942 - 20950
[2] Patent: CN103980186, 2016, B. Location in patent: Paragraph 0044-0046