Patent 11318212 was granted and assigned to Daiichi Sankyo on May, 2022 by the United States Patent and Trademark Office.
A method for producing a compound represented by formula (C) wherein R1 represents an amino group protected with a protecting group, the method comprising a step of subjecting a compound represented by formula (B) wherein R1 represents the same meaning as above, to intramolecular cyclization to convert the compound into the compound represented by formula (C).