Cephalosporin derivatives

An intermediate compound in the synthesis of cephalosporin derivatives represented by the formula (XV):

• ##STR173## or salts, solvates or salts of solvates thereof, wherein R.sup.1 represents a hydrogen atom or a amino-protecting group, R.sup.2 represents a hydrogen atom or a methyl group, R.sup.3 represents a carboxyl group or a protected carboxyl group, R.sup.7 represents a hydrogen atom, a chlorine atom, a carboxyl group, a protected carboxyl group, a methyl group, an isopropyl group, a hydroxy group, a methoxy group or an acetoxy group, R.sup.8 and R.sup.9 are the same or different and represent hydrogen atoms, hydroxy groups, methoxy groups, ethoxy groups, acetoxy groups, chloroacetoxy groups, butanoyloxy groups, methanesulfonyloxy groups;
• p-toluenesulfonyloxy groups, amino groups, acetamino groups, benzyloxycarabonylamino groups, methanesulfonyl groups, or together an ethylenedioxy group or a carbonyldioxy group, R.sup.10 represents a hydrogen atom, a hydroxy group, an acetoxy group, a methoxy group, or a chloracetoxy group, with the proviso that R.sup.7, R.sup.8, R.sup.9 and R.sup.10 do not represent hydrogen atoms at the same time, R.sup.15 represents a hydrogen atom or a carboxyl-protecting group, and the bond shown with a wavy line represents a bond of anti-form or syn-form.