Uses
Nα-Cbz-L-asparagine is an N-Cbz-protected form of L-Asparagine (A790005). L-Asparagine was first isolated by Robiquet and Vauquelin from asparagus juice (a high source of L-asparagine). L-Asparagine is often incorporated into proteins, and is a basis for some cancer therapies as certain cancerous cells require L-asparagine for growth.
Synthesis
At 0 °C, 6.05 g (45 mmol) of L-asparagine was dissolved in 100 mL of 10% Na2CO3 aqueous solution, followed by the addition of 56 mL of 1,4-dioxane and 6.9 mL (40 mmol) of benzyl chloroformate. The reaction mixture was stirred overnight at room temperature and poured into 300 mL of water. The aqueous phase was extracted three times with ether. The aqueous phase was acidified with 2N HCl aqueous solution until a white precipitate precipitated. The precipitate was collected by filtration and washed well with ether to give Cbz-L-asparagine (Compound 14) as an off-white solid (9 g, 84% yield); Mass Spectra (ESI): m/z = 267 [M + H]+, 289 [M + Na]+.
References
[1] Tetrahedron Asymmetry, 2015, vol. 26, # 21-22, p. 1273 - 1280
[2] Tetrahedron, 2000, vol. 56, # 16, p. 2513 - 2522
[3] Tetrahedron Letters, 2015, vol. 56, # 26, p. 3999 - 4001
[4] European Journal of Organic Chemistry, 2014, vol. 2014, # 31, p. 7015 - 7022
[5] Chemical Communications, 2016, vol. 52, # 60, p. 9438 - 9441
