| abstract |
The present invention precipitates crystals of the compound represented by the formula (E) -I under acid coexistence, thereby shifting the equilibrium of isomerization of the compound represented by the formula (Z) -I. The manufacturing method of the compound represented by I is related. (Wherein R represents a protecting group of carboxylic acid, R 1 represents a hydrogen atom or a halogen atom, R 2 represents a halogen atom, cycloalkylsulfonyl, substituted or unsubstituted alkylsulfonyl, substituted or unsubstituted alkylthio, Substituted or unsubstituted aminosulfonyl, substituted or unsubstituted non-aromatic heterocyclic thio, substituted or unsubstituted non-aromatic heterocyclic sulfonyl, substituted or unsubstituted heteroarylsulfonyl, alkenyloxy, substituted or unsubstituted alkoxy, or substituted Or unsubstituted heteroarylthio) |