Practical large scale synthesis of N-benzoyl-(2R, 3S)-phenylisoserine methyl ester of the Taxol side chain has been attained from the coupling of chiral imine of N-[(S)-methylbenzyl] benzaldimine with (Z)-α-methoxy trimethylsilyl ketene acetal followed by the sequential reactions of lactamization, demethylation, methanolysis and N-benzoylation.
![(3R,4S)-3-hydroxy-4-phenyl-1-[(1S)-1-phenylethyl]azetidin-2-one结构式](https://image.chemsrc.com/caspic/419/154306-81-7.png)