p-methoxybenzyl (6R,7R)-7-[(Z)-2-ethoxyimino-2-(2-tritylaminothiazol-4-yl)acetamido]-3-chloromethyl-3-cephem-4-carboxylate                                                                                                                                                                                                                                                                                                          以73%的产率得到p-methoxybenzyl (6R,7R)-7-[(Z)-2-ethoxyimino-2-(2-tritylaminothiazol-4-yl)acetamido]-3-[2-(3-methylimidazo[5,1-b]thiazol-2-yl)vinyl]-3-cephem-4-carboxylate