Patent ID: 11891455
Assignee: GALIMEDIX THERAPEUTICS INC
Field: Pharmaceuticals (Chemistry)
Classification: CPC C  A | IPC A  C

Claim 12:
13. A process for preparing Form II of (R)-2-[2-amino-3-(indol-3-yl)propionylamino]-2-methylpropionic acid of claim 1, comprising
(a) reacting compound (2), with tert-butyl-2-aminoisobutyrate (3) in the presence of 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine chloride (DMTMM) to give compound (4), (b) removing the Boc group from compound (4) with hydrogen chloride gas to give compound (5);, (c) providing a solution of compound (5) in water and adjusting the pH of the solution to about 5.5-5.7 to give a precipitate;
(d) mixing the precipitate from step (c) with an aqueous HCl to provide a solution;
(e) cooling the solution of step (d) to about 0-5° C., followed by adjusting the pH of the solution to about 5.6 with a 20% NaOH aqueous solution
(f) stirring the solution at about 0-5° C. until precipitation is complete; and
(g) isolating the resulting precipitate to give Form II of compound (R)-2-[2-amino-3-(indol-3-yl)propionylamino]-2-methylpropionic acid.
(h) optionally drying the isolated precipitate at 0-5° C. by a drying agent.