The present invention relates to a processing method for preparing lovastatin
and simvastatin which comprises the steps of (1) performing lactonization of mevinic
acid and its homologous compounds in the presence of a mixed organic solvent without
an acid catalyst through nitrogen sweep; and (2) making crystals. In the process
of the present invention, lovastatin and simvastatin highly purified can be produced
in a high yield and especially, heterodimers formed as a by-product can be reduced
remarkably. Therefore, the processing method of the present invention can be convenient
and economical.
