A salt composed of a compound represented by the formula (4) and a compound represented by the formula (5) is obtained by mixing the compound represented by the formula (4) and the compound represented by the formula (5) And reacting the protecting group P1And a step of deprotecting the compound represented by the formula (6). Embedded image (Wherein P1Represents a protecting group, and P2Represents a protecting group. )式(4)で表される化合物と、式(5)で表される化合物とを混合して、式(4)で表される化合物と式(5)で表される化合物とからなる塩を生成させる工程と、前記塩の保護基P1を脱保護させる工程と、を含む、式(6)で表される化合物の製造方法を提供する。 【化1】(式中、P1は保護基を示し、P2は保護基を示す。)