| abstract |
The objective of the present invention is to provide a tyrosine derivative which is useful as a melatonin receptor 1 MT 1 antagonist, and a method for efficiently manufacturing a specific m-tyrosine derivative in which an iodine atom is introduced to the paraposition of a phenolic hydroxl group on the benzene ring of m-tyrosine with excellent regioselectivity and high yield. This tyrosine derivative is characterized by being represented by formula (I). [In the formula, R 1 represents an amino group protecting group or the like, R 2 represents a carboxy group protecting group or the like, R 3 represents a hydrogen atom or the like, R 4 represents a halogen atom or the like, A represents -(CH 2 ) l -[Z(CH 2 ) m ] n -, and X represents a leaving group.] |