Ethane, 1-chloro-1-ethoxy- → (2R,3S)-N-benzoyl-O-(1-ethoxyethyl)-3-phenyl-isoserine

Beteiligte Stoffe

Reaktionsschritte

The N-benzoyl-(2R,3S)-3-phenyl-isoserine, as prepared in Example 34, is treated with 1-chloroethyl ethyl-ether in the presence of a tertiary amine to produce optically pure (2R,3S)-N-benzoyl-O-(1-ethoxyethyl)-3-phenyl-isoserine (2). 7-tri-ethylsilyl baccatin III (1), as synthesized according to Denis et at. (J. Amer. Chem. Soc. 110:5417, 1988), is added to 6 equiv of optically pure (2R,3S)-N-benzoyl-O-(1-ethoxyethyl)-3-phenyl-isoserine (2), 6 equiv of di-2-pyridyl carbonate (DPC), and 2 equiv of 4-(dimethylamino) pyridine (DMAP) in toluene solution (0.02M). This mixture reacts at 73° C. for 100 hours to produce the C-2', C-7-protected taxol derivative (3).

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