| 摘要 |
<p>A synthetic method for the preparation of the anti-tumor drug Etoposide. In one embodiment, the method includes the direct condensation of 4'-demethyl epipodophylloxin with 2,3-di-O-dichloroacetyl-(4,6-O-ethylidene)-β-D-glucopyranose in the presence of trimethylsilyl trifluoromethane sulfonate (TMSOTf) to yield 4'-demethylepipodophyllotoxin-4-(2,3-di-O-dichloroacetyl-4,6-0-ethylidene)-β-D-glucopyranoside, followed by conversion of the same to etoposide. Other methods include use of different Lewis acids as catalyst, as well as different substituted glucopyranosides. This method provides enhanced yields over existing synthetic techniques, reduced reaction times and permits more favorable isolation reaction procedures.</p> |
