Disclosed is a method of preparing a compound represented by structural formula (II), and physiological salts thereof. R<1> is -H, an aliphatic group, a substituted aliphatic group, an aryl group or a substituted aryl group. R<2> is a substituted or unsubstituted 2-hydroxy-1-ethyl group. Ring A is a substituted or unsubstituted aryl group. Ring B is substituted or unsubstituted at position two. The method comprises reacting a substituted or unsubstituted aryl hydrazine or salt derived from a substituted or unsubstituted aryl hydrazine with a compound represented by structural formula (III).
