Synthesis of echinocandin antifungal agent
The present invention relates to echinocandin cyclopeptides and to methods for preparing echinocandin cyclopeptides.
1. A method of synthesizing compound 1:
said method comprising hydrolyzing a compound of formula (IIa):
wherein X − is an anion, to form compound 1, or a salt or neutral form thereof.
2. The method of claim 1 , wherein the hydrolyzing comprises contacting the compound of formula (IIa) with an aqueous base.
3. The method of claim 2 , wherein the hydrolyzing comprises diluting with at least 5 volumes relative to anidulafungin of water:acetonitrile mixture of about 80:20 to 50:50 and adjusting the pH with base to a pH of from 2 to 5.
4. The method of claim 2 , wherein the hydrolyzing is performed at a temperature of less than 15° C.
5. The method of any one of claims 1-4 , wherein after hydrolyzing the compound of formula (IIa) to form compound 1, compound 1 is separated from 3,4-dimethoxyphenylboronic acid by passage across an ion exchange column.