tofacitinib citrate and its Impurities
A janus kinase (JAK) inhibitor class of drug used for the treatment of rheumatoid arthritis (RA)Reference standards of Tofacitinib Citrate API,and its pharmacopeial, non pharmacopeial impurities, and stable isotopes are listed below.

![3-((3R,4R)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyr PA 47 13600](https://pharmaffiliates.com/public/pimages/PA4713600.jpg)
3-((3R,4R)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanoic Acid
3-((3R,4R)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanoic Acid
Catalogue No.:PA 47 13600
CAS :
2328165-36-0
Molecular Formula : C16H21N5O3
Molecular Weight : 331.37

![3-((3R,4R)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyr PA 47 13610](https://pharmaffiliates.com/public/pimages/PA4713610.jpg)
3-((3R,4R)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanamide
3-((3R,4R)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanamide
Catalogue No.:PA 47 13610
CAS :
1675248-19-7
Molecular Formula : C16H22N6O2
Molecular Weight : 330.38

![3-(4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4 PA 47 13660](https://pharmaffiliates.com/public/pimages/PA4713660.jpg)
3-(4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile
3-(4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile
Catalogue No.:PA 47 13660
CAS :
344418-92-4
Molecular Formula : C16H20N6O
Molecular Weight : 312.37

![1-((3R,4R)-4-Methyl-3-(methyl(1H-pyrrolo[2,3-d]pyr PA 47 13710](https://pharmaffiliates.com/public/pimages/PA4713710.jpg)
1-((3R,4R)-4-Methyl-3-(methyl(1H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)ethan-1-one
1-((3R,4R)-4-Methyl-3-(methyl(1H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)ethan-1-one
Catalogue No.:PA 47 13710
CAS :
477600-76-3
Molecular Formula : C15H21N5O
Molecular Weight : 287.37

![3-((3R,4R)-3-((6,7-Dihydro-5H-pyrrolo[2,3-d]pyrimi PA 47 13740](https://pharmaffiliates.com/public/pimages/PA4713740.jpg)
3-((3R,4R)-3-((6,7-Dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)(methyl)amino)-4-methylpiperidin-1-yl)-3-oxopropanenitrile 2-hydroxypropane-1,2,3-tricarboxylate
3-((3R,4R)-3-((6,7-Dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)(methyl)amino)-4-methylpiperidin-1-yl)-3-oxopropanenitrile 2-hydroxypropane-1,2,3-tricarboxylate
Catalogue No.:PA 47 13740
CAS :
1809002-40-1
Molecular Formula : C22H30N6O8
Molecular Weight : 506.52

![3-(4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4 PA 47 13750](https://pharmaffiliates.com/public/pimages/PA4713750.jpg)
3-(4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile 2-hydroxypropane-1,2,3-tricarboxylate
3-(4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile 2-hydroxypropane-1,2,3-tricarboxylate
Catalogue No.:PA 47 13750
CAS :
2664002-63-3
Molecular Formula : C22H28N6O8
Molecular Weight : 504.5

![3-((3S,4S)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyr PA 47 13760](https://pharmaffiliates.com/public/pimages/PA4713760.jpg)
3-((3S,4S)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile 2-Hydroxypropane-1,2,3-tricarboxylate
3-((3S,4S)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile 2-Hydroxypropane-1,2,3-tricarboxylate
Catalogue No.:PA 47 13760
CAS :
2174011-55-1
Molecular Formula : C22H28N6O8
Molecular Weight : 504.5


3-((3R,4R)-3-(((5S,6R)-5,6-Dihydroxy-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)(methyl)amino)-4-methylpiperidin-1-yl)-3-oxopropanenitrile
3-((3R,4R)-3-(((5S,6R)-5,6-Dihydroxy-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)(methyl)amino)-4-methylpiperidin-1-yl)-3-oxopropanenitrile
Catalogue No.:PA 47 13780
CAS :
2101951-13-5
Molecular Formula : C16H22N6O3
Molecular Weight : 346.39


3-((3R,4R)-3-(((5R,6S)-5,6-Dihydroxy-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)(methyl)amino)-4-methylpiperidin-1-yl)-3-oxopropanenitrile
3-((3R,4R)-3-(((5R,6S)-5,6-Dihydroxy-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)(methyl)amino)-4-methylpiperidin-1-yl)-3-oxopropanenitrile
Catalogue No.:PA 47 13790
CAS :
2101958-24-9
Molecular Formula : C16H22N6O3
Molecular Weight : 346.39


3-((3R,4R)-4-Methyl-3-(methyl((5R,6S)-2,5,6-trihydroxy-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile
3-((3R,4R)-4-Methyl-3-(methyl((5R,6S)-2,5,6-trihydroxy-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile
Catalogue No.:PA 47 13800
CAS :
NA
Molecular Formula : C16H22N6O4
Molecular Weight : 362.39


3-((3R,4R)-4-Methyl-3-(methyl((5S,6R)-2,5,6-trihydroxy-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile
3-((3R,4R)-4-Methyl-3-(methyl((5S,6R)-2,5,6-trihydroxy-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile
Catalogue No.:PA 47 13810
CAS :
NA
Molecular Formula : C16H22N6O4
Molecular Weight : 362.39


3-((3R,4R)-4-Methyl-3-(methyl(5-oxo-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile
3-((3R,4R)-4-Methyl-3-(methyl(5-oxo-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile
Catalogue No.:PA 47 13820
CAS :
2101951-20-4
Molecular Formula : C16H20N6O2
Molecular Weight : 328.38


Ethyl 4-cyano-3-imino-5-((3R,4R)-4-methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-5-oxopentanoate
Ethyl 4-cyano-3-imino-5-((3R,4R)-4-methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-5-oxopentanoate
Catalogue No.:PA 47 13830
CAS :
2102039-99-4
Molecular Formula : C21H27N7O3
Molecular Weight : 425.49


3-Imino-5-((3S,4R)-4-methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)cyclohexyl)-2-((3R,4R)-4-methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidine-1-carbonyl)-5-oxopentanenitrile
3-Imino-5-((3S,4R)-4-methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)cyclohexyl)-2-((3R,4R)-4-methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidine-1-carbonyl)-5-oxopentanenitrile
Catalogue No.:PA 47 13840
CAS :
NA
Molecular Formula : C33H41N11O2
Molecular Weight : 623.77

![3-((3R,4R)-3-((2-Chloro-7H-pyrrolo[2,3-d]pyrimidin PA 47 13850](https://pharmaffiliates.com/public/pimages/PA4713850.jpg)
3-((3R,4R)-3-((2-Chloro-7H-pyrrolo[2,3-d]pyrimidin-4-yl)(methyl)amino)-4-methylpiperidin-1-yl)-3-oxopropanenitrile
3-((3R,4R)-3-((2-Chloro-7H-pyrrolo[2,3-d]pyrimidin-4-yl)(methyl)amino)-4-methylpiperidin-1-yl)-3-oxopropanenitrile
Catalogue No.:PA 47 13850
CAS :
1616761-00-2
Molecular Formula : C16H19ClN6O
Molecular Weight : 346.82


N-((3R,4R)-1-Benzyl-4-methylpiperidin-3-yl)-N-methyl-7-tosyl-7H-pyrrolo[2,3-d]pyrimidin-4-amine
N-((3R,4R)-1-Benzyl-4-methylpiperidin-3-yl)-N-methyl-7-tosyl-7H-pyrrolo[2,3-d]pyrimidin-4-amine
Catalogue No.:PA 47 0131000
CAS :
923036-30-0
Molecular Formula : C27H31N5O2S
Molecular Weight : 489.64


Butyl 3-((3R,4R)-4-methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanoate
Butyl 3-((3R,4R)-4-methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanoate
Catalogue No.:PA 47 0131002
CAS :
2227199-31-5
Molecular Formula : C20H29N5O3
Molecular Weight : 387.48


3-(4-(((3R,4R)-1-(2-Cyanoacetyl)-4-methylpiperidin-3-yl)(methyl)amino)-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-3-oxopropanenitrile
3-(4-(((3R,4R)-1-(2-Cyanoacetyl)-4-methylpiperidin-3-yl)(methyl)amino)-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-3-oxopropanenitrile
Catalogue No.:PA 47 0131003
CAS :
2459302-77-1
Molecular Formula : C19H21N7O2
Molecular Weight : 379.42

![1-((3R,4R)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyr PA 47 0131005](https://pharmaffiliates.com/public/pimages/PA470131005.jpg)
1-((3R,4R)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)ethan-1-one
1-((3R,4R)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)ethan-1-one
Catalogue No.:PA 47 0131005
CAS :
477600-76-3
Molecular Formula : C15H21N5O
Molecular Weight : 287.37


Ethyl 4-cyano-5-((3R,4R)-3-((6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)(methyl)amino)-4-methylpiperidin-1-yl)-3-imino-5-oxopentanoate
Ethyl 4-cyano-5-((3R,4R)-3-((6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)(methyl)amino)-4-methylpiperidin-1-yl)-3-imino-5-oxopentanoate
Catalogue No.:PAI 47 013001
CAS :
NA
Molecular Formula : C21H29N7O3
Molecular Weight : 427.51


4-Cyano-2-hydroxy-5-(4-methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-5-oxopentane-1,2,3-tricarboxylic Acid
4-Cyano-2-hydroxy-5-(4-methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-5-oxopentane-1,2,3-tricarboxylic Acid
Catalogue No.:PA 47 0131007
CAS :
NA
Molecular Formula : C22H26N6O8
Molecular Weight : 502.48