Diphenylmethyl(6R,7R)-8-oxo-7-(phenylacetyl)amino-3-vinyl-5-thia-l-azabicyclo[4.2.0] oct-2-ene-2-carboxylate(8) were synthesized according to Wittig Reaction via fractional step method and one-pot process separately.

• a、C-3位直接与双键相连的头孢菌素衍生物：分别以“分步法”与“一锅法”采用魏悌锡(Wittig)反应合成了(6R；7R)-7-苯乙酰氨基-8-氧代-5-硫-1-氮杂双环[4.；2