Process of preparing etoposide phosphate and etoposide

摘要

Etoposide phosphate is prepared by coupling dibenzyl 4'-demethyl-4-epipodophyllotoxin-4'-phosphate with 2,3-di-O-benzyl-4,6-O-ethylidene- alpha , beta -D-glucopyranose in a solvent and subsequently removing the protecting groups. The tetra-benzyl protected etoposide phosphate is recrystallized from methanol or directly crystallized from acetonitrile by adding methanol to yield substantially the pure C-1''- beta form. The benzyl protecting groups are simultaneously removed by hydrogenation to produce etoposide phosphate in high yields. In a further embodiment, etoposide phosphate is treated with a phosphatase enzyme to yield etoposide.