US 11,667,642 B2
Method for producing 3,6-disubstituted-imidazo[1,2-b]pyridazine derivative
Ryoji Koike, Yokohama (JP); Yoshifumi Hachisu, Yokohama-sh (JP); Takafumi Kitawaki, Sagamihara (JP); and Shohei Shiraishi, Chigasaki (JP)
Assigned to Daiichi Sankyo Company, Limited, Tokyo (JP)
Filed by Daiichi Sankyo Company, Limited, Tokyo (JP)
Filed on Feb. 1, 2021, as Appl. No. 17/164,684.
Application 17/164,684 is a division of application No. 16/494,116, granted, now 11,028,091, previously published as PCT/JP2018/009596, filed on Mar. 13, 2018.
Claims priority of application No. JP2017-049138 (JP), filed on Mar. 14, 2017.
Prior Publication US 2021/0171532 A1, Jun. 10, 2021
Int. Cl. C07D 487/04 (2006.01)
CPC C07D 487/04 (2013.01) 15 Claims
 
1. A method for producing a compound represented by Formula (V) or a salt thereof:

OG Complex Work Unit Chemistry
the method comprising:
a step of reacting a compound represented by Formula (III) or a salt thereof:

OG Complex Work Unit Chemistry
wherein PG represents a protecting group for a nitrogen atom, with a compound represented by Formula (IV) or a salt thereof:

OG Complex Work Unit Chemistry
and a step of deprotecting PG on the nitrogen atom.