US 12,234,209 B2
N-alkylation of acridans
Anand Natrajan, Manchester, NH (US)
Assigned to Siemens Healthcare Diagnostics Inc., Tarrytown, NY (US)
Filed by Siemens Healthcare Diagnostics Inc., Tarrytown, NY (US)
Filed on Nov. 15, 2021, as Appl. No. 17/454,916.
Application 17/454,916 is a continuation of application No. 17/250,131, granted, now 11,203,573, previously published as PCT/US2019/038955, filed on Jun. 25, 2019.
Claims priority of provisional application 62/689,811, filed on Jun. 25, 2018.
Prior Publication US 2022/0073468 A1, Mar. 10, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. C07D 219/06 (2006.01)
CPC C07D 219/06 (2013.01) 20 Claims
 
1. A method for the N-alkylation of an acridan compound comprising reacting said acridan compound with a protected sulfonate triflate compound having the structure of formula (R1):

OG Complex Work Unit Chemistry
wherein G is an acid-labile protecting group; and
—RL— is a C1-20 linear or branched bivalent hydrocarbon radicals; optionally substituted with one or more heteroatoms, and combinations thereof, and wherein RL optionally comprises a zwitterionic linker group;
wherein said acridan has the structure of formula (A1):

OG Complex Work Unit Chemistry
wherein “m” and “n” are independently 0-4 and at least one of “m” or “n” is greater than 0;
R1 and R2 are independently selected from electron donating groups; and
R3 is hydrogen or a C1-C45 hydrocarbon radical optionally substituted with one or more heteroatoms and wherein R3 may optionally comprise a zwitterionic group and/or a zwitterionic linker group.