Cephalosporin compositions and methods of manufacture

A method for preparing a compound of formula (II), or a salt thereof,

• comprising the step of reacting a compound of formula (III), or a salt thereof,
• with a compound of formula (IV), or a salt thereof,
• in a mixture comprising an organic solvent and water, to form a compound of formula (II), or a salt thereof;
• wherein:
• R1 is selected from the group consisting of:
• wherein Z′ is independently hydrogen or an oxygen protecting group;
• Y is selected from the group consisting of:
• wherein R′ is selected from the group consisting of hydrogen and an oxygen protecting group;
• R2 is hydrogen;
• R3 is selected from the group consisting of hydrogen and an oxygen protecting group;
• and
• R4 and R4′, are each independently selected from the group consisting of:
• and —CH═CH2,
• wherein each occurrence of A{circle around (−)} is independently an anion, and
• X is —OSO2R8, wherein R8 is methyl.