PROCESS FOR THE PREPARATION OF VERDIPERSTAT

1 . A process for preparing verdiperstat comprising the steps of:

reacting a compound having formula

or a salt thereof, wherein R is the same or different and is each independently a C1-C5 alkyl, with 3-(dimethylamino)acrylonitrile to obtain a compound having formula

and

converting the compound having formula

to verdiperstat.

2 . The process according to claim 1 , wherein the step of converting the compound having formula

to verdiperstat comprises:

converting the compound having formula

to a compound having formula

or a salt thereof; and

converting the compound having formula

or a salt thereof to verdiperstat.

3 . The process according to claim 1 , wherein the step of reacting a compound having formula

or a salt thereof, wherein R is a C1-C5 alkyl with 3-(dimethylamino)acrylonitrile is conducted in the presence of an acid.

4 . The process according to claim 3 , wherein the acid is a carboxylic acid.

5 . The process according to claim 2 , wherein the step of converting the compound having formula

to a compound having formula

or a salt thereof is conducted in the presence of a base.

6 . The process according to claim 5 , wherein the base is a metal alkoxide.

7 . The process according to claim 2 , wherein the step of converting the compound having formula

or a salt thereof to verdiperstat comprises reacting the compound having formula

or a salt thereof with a compound having formula

wherein X is a leaving group to obtain a compound having formula

or a salt thereof.

8 . The process according to claim 7 , wherein the leaving group is an organic sulfonate group.

9 . The process according to claim 7 , wherein the step of reacting the compound having fomula

or a salt thereof with a compound having formula

is conducted in the presence of a base, and optionally, a metal iodide.

10 . The process according to claim 9 , wherein the base is a salt of an inorganic acid, and wherein the metal is an alkali metal.

11 . The process according to claim 7 , wherein the step of converting the compound having formula

or a salt thereof to verdiperstat further comprises reacting the compound having formula

or a salt thereof with a compound having formula

wherein R′ is H or an organic group, to obtain a compound having formula

12 . The process according to claim 7 , wherein the step of converting the compound having formula

or a salt thereof to verdiperstat further comprises converting the compound having formula

to verdiperstat.

13 . The process according to claim 12 , wherein the step of converting the compound having formula

to verdiperstat is conducted in the presence of a base.

14 . The process according to claim 13 , wherein the base is a metal hydroxide.

15 . The process according to claim 1 , wherein the step of reacting a compound having formula

or a salt thereof, wherein R is a C1-C5 alkyl, with 3-(dimethylamino)acrylonitrile is preceded by reacting cyanoacetic acid with N, N-dimethylformamide dimethyl acetal to obtain 3-(dimethylamino)acrylonitrile.

16 . A process for preparing verdiperstat comprising:

Step (a): reacting cyanoacetic acid with N, N-dimethylformamide dimethyl acetal to obtain 3-(dimethylamino)acrylonitrile;

Step (b): reacting a compound having formula

or a salt thereof,

wherein R is the same or different and is each independently a C1-C5 alkyl, with 3-(dimethylamino)acrylonitrile to obtain a compound having formula

Step (c): converting the compound having formula

to a compound having formula

or a salt thereof;

Step (d): reacting the compound having formula

or a salt thereof with a compound having formula

wherein X is a leaving group to obtain a compound having formula

or a salt thereof;

Step (e): reacting the compound having formula

or a salt thereof with a compound having formula

wherein R′ is H or an organic group, to obtain a

compound having formula

and

Step (f): converting the compound having formula

to verdiperstat.

17 . A composition comprising:

a compound having formula

or a salt thereof, wherein R is the same or different and is each independently a C1-C5 alkyl; and

3-(dimethylamino)acrylonitrile.

18 . The composition according to claim 17 , further comprising a solvent, an acid, or a combination thereof.

19 . The composition according to claim 18 , wherein the solvent is a hydrocarbon solvent, a halogenated hydrocarbon solvent, or a combination thereof.

20 . The composition according to claim 19 , wherein the acid is a carboxylic acid.

21 . A composition comprising verdiperstat and a compound having formula

wherein R′ is H or an organic group.

22 . The composition of claim 21 , wherein the compound having formula

is present in an amount of 0.2 percent by weight or greater based on the total weight of the composition.

23 . The composition of claim 21 , wherein the compound having formula

is present in an amount of less than 0.2 percent by weight based on the total weight of the composition.