pemetrexed and its Impurities
Pemetrexed is used to treat certain types of cancer. Pemetrexed is a chemotherapy drug manufactured and marketed by Eli Lilly and Company.Reference standards of Pemetrexed API,and its pharmacopeial, non pharmacopeial impurities, and stable isotopes are listed below.


Pemetrexed Disodium Heptahydrate - Impurity A (Disodium Salt)
(2S)-2-[[4-[2-(2-Amino-1-methyl-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5- yl)ethyl]benzoyl]amino]pentanedioic Acid Disodium Salt
Catalogue No.:PA 16 09011
CAS :
NA
Molecular Formula : C21H21N5Na2O6
Molecular Weight : 485.4


Pemetrexed Disodium Heptahydrate - Impurity B
(2S,2′S)-2,2′-[[(5R)-2,2′-Diamino-4,4′,6-trioxo-1,4,4′,6,7,7′-hexahydro-1′H,5H-5,6′-bipyrrolo[2,3-d]pyrimidine-5,5′-diyl]bis(ethylenebenzene-4,1-diylcarbonylimino)]dipentanedioic Acid
Catalogue No.:PA 16 09020
CAS :
1802552-04-0
Molecular Formula : C40H40N10O13
Molecular Weight : 868.82


Pemetrexed Disodium Heptahydrate - Impurity C
(2S,2'S)-2,2'-[[(5S)-2,2'-Diamino-4,4',6-trioxo-1,4,4',6,7,7'-hexahydro-1'H,5H-5,6'-bipyrrolo[2,3-d]pyrimidine-5,5'-diyl]bis(ethylenebenzene-4,1-diylcarbonylimino)]dipentanedioic Acid
Catalogue No.:PA 16 09030
CAS :
1802552-16-4
Molecular Formula : C40H40N10O13
Molecular Weight : 868.8


Pemetrexed Disodium Heptahydrate - Impurity D
(2S)-2-[[(4S)-4-[[4-[2-(2-Amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoyl]amino]-4-carboxybutanoyl]amino]pentanedioic Acid
Catalogue No.:PA 16 09040
CAS :
144051-68-3
Molecular Formula : C25H28N6O9
Molecular Weight : 556.52


Pemetrexed Disodium Heptahydrate - Impurity D (Trisodium Salt)
(2S)-2-[[(4S)-4-[[4-[2-(2-Amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5- yl)ethyl]benzoyl]amino]-4-carboxybutanoyl]amino]pentanedioic Acid Trisodium Salt
Catalogue No.:PA 16 09041
CAS :
1265908-59-5
Molecular Formula : C25H25N6Na3O9
Molecular Weight : 622.47


{4-[2-(2-Amino-1-methyl-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoyl}-4-L-glutamyl-L-glutamic Acid
{4-[2-(2-Amino-1-methyl-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoyl}-4-L-glutamyl-L-glutamic Acid
Catalogue No.:PA 16 09540
CAS :
NA
Molecular Formula : C26H30N6O9
Molecular Weight : 570.55


Sodium (S)-2-(4-(2-(2-amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-methoxy-5-oxopentanoate
Sodium (S)-2-(4-(2-(2-amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-methoxy-5-oxopentanoate
Catalogue No.:PA 16 09570
CAS :
1265908-60-8
Molecular Formula : C21H22N5NaO6
Molecular Weight : 463.42


Sodium (4R)-4-{[4-(2-{2-Amino-4-oxo-1H,4H,7H- pyrrolo[2,3-d]pyrimidin-5- yl}ethyl)phenyl]formamido}-5-methoxy-5- oxopentanoate
Sodium (4R)-4-{[4-(2-{2-Amino-4-oxo-1H,4H,7H- pyrrolo[2,3-d]pyrimidin-5- yl}ethyl)phenyl]formamido}-5-methoxy-5- oxopentanoate
Catalogue No.:PA 16 09600
CAS :
1265908-61-9
Molecular Formula : C21H22N5NaO6
Molecular Weight : 463.42


N-[4-[2-(2-Amino-4,7-dihydro-4-oxo-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoyl]-L-glutamic Acid 1,5-Diethyl Ester 4-Methylbenzenesulfonate
N-[4-[2-(2-Amino-4,7-dihydro-4-oxo-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoyl]-L-glutamic Acid 1,5-Diethyl Ester 4-Methylbenzenesulfonate
Catalogue No.:PAI 16 014010
CAS :
165049-28-5
Molecular Formula : C31H37N5O9S
Molecular Weight : 655.72


(S)-Diethyl 2-(4-(2-(2-amino-1-methyl-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)pentanedioate
(S)-Diethyl 2-(4-(2-(2-amino-1-methyl-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)pentanedioate
Catalogue No.:PAI 16 014020
CAS :
NA
Molecular Formula : C25H31N5O6
Molecular Weight : 497.54


(S)-2-(4-(2-(2-Amino-1-methyl-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-(((S)-1,5-diethoxy-1,5-dioxopentan-2-yl)amino)-5-oxopentanoic Acid
(S)-2-(4-(2-(2-Amino-1-methyl-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-(((S)-1,5-diethoxy-1,5-dioxopentan-2-yl)amino)-5-oxopentanoic Acid
Catalogue No.:PAI 16 014030
CAS :
NA
Molecular Formula : C30H38N6O9
Molecular Weight : 626.66


(S)-2-((S)-4-(4-(2-(2-Amino-1-methyl-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-4-carboxybutanamido)pentanedioic Acid
(S)-2-((S)-4-(4-(2-(2-Amino-1-methyl-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-4-carboxybutanamido)pentanedioic Acid
Catalogue No.:PAI 16 014040
CAS :
NA
Molecular Formula : C26H30N6O9
Molecular Weight : 570.55


(S)-Diethyl 2-((S)-4-(4-(2-(2-amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-methoxy-5-oxopentanamido)pentanedioate
(S)-Diethyl 2-((S)-4-(4-(2-(2-amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-methoxy-5-oxopentanamido)pentanedioate
Catalogue No.:PAI 16 014090
CAS :
NA
Molecular Formula : C30H38N6O9
Molecular Weight : 626.66


(S)-Diethyl 2-((S)-4-(4-(2-(2-amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-methoxy-5-oxopentanamido)pentanedioate 4-methylbenzenesulfonate
(S)-Diethyl 2-((S)-4-(4-(2-(2-amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-methoxy-5-oxopentanamido)pentanedioate 4-methylbenzenesulfonate
Catalogue No.:PAI 16 014100
CAS :
NA
Molecular Formula : C37H46N6O12S
Molecular Weight : 798.86


(S)-Diethyl 2-((S)-4-(4-(2-(2-amino-1-methyl-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-methoxy-5-oxopentanamido)pentanedioate
(S)-Diethyl 2-((S)-4-(4-(2-(2-amino-1-methyl-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-methoxy-5-oxopentanamido)pentanedioate
Catalogue No.:PAI 16 014110
CAS :
NA
Molecular Formula : C31H40N6O9
Molecular Weight : 640.68


Di lithium (4-(2-(2-amino-4,6-dioxo-4,5,6,7-tetrahydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-L-glutamate
Di lithium (4-(2-(2-amino-4,6-dioxo-4,5,6,7-tetrahydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-L-glutamate
Catalogue No.:PA 16 09610
CAS :
NA
Molecular Formula : C20H19Li2N5O7
Molecular Weight : 455.28


(4-(2-(2-Amino-6-hydroxy-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-L-glutamic Acid
(4-(2-(2-Amino-6-hydroxy-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-L-glutamic Acid
Catalogue No.:PA 16 09620
CAS :
NA
Molecular Formula : C20H21N5O7
Molecular Weight : 443.42


(4-(2-(2,2'-Diamino-5-(4-((1-carboxy-4-(2-carboxyethoxy)-4-oxobutyl)carbamoyl)phenethyl)-6-hydroxy-4,4'-dioxo-4,4',5,6,7,7'-hexahydro-3H,3'H-[5,6'-bipyrrolo[2,3-d]pyrimidin]-5'-yl)ethyl)benzoyl)glutamic Acid
(4-(2-(2,2'-Diamino-5-(4-((1-carboxy-4-(2-carboxyethoxy)-4-oxobutyl)carbamoyl)phenethyl)-6-hydroxy-4,4'-dioxo-4,4',5,6,7,7'-hexahydro-3H,3'H-[5,6'-bipyrrolo[2,3-d]pyrimidin]-5'-yl)ethyl)benzoyl)glutamic Acid
Catalogue No.:PA 16 09630
CAS :
NA
Molecular Formula : C43H46N10O15
Molecular Weight : 942.9

![4-[2-(2-Amino-4,7-dihydro-4-oxo-3H-pyrrolo[2,3-d]p PA 16 09640](https://www.pharmaffiliates.com/pimages/PA1609640.jpg)
4-[2-(2-Amino-4,7-dihydro-4-oxo-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoic Acid Methyl Ester
4-[2-(2-Amino-4,7-dihydro-4-oxo-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoic Acid Methyl Ester
Catalogue No.:PA 16 09640
CAS :
155405-80-4
Molecular Formula : C16H16N4O3
Molecular Weight : 312.32


Methyl 4-(2-(2-amino-4,6-dioxo-4,5,6,7-tetrahydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoate
Methyl 4-(2-(2-amino-4,6-dioxo-4,5,6,7-tetrahydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoate
Catalogue No.:PA 16 0091004
CAS :
1320346-43-7
Molecular Formula : C16H16N4O4
Molecular Weight : 328.33


4-[2-(2-Amino-4,5,6,7-tetrahydro-4,6-dioxo-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoic Acid
4-[2-(2-Amino-4,5,6,7-tetrahydro-4,6-dioxo-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoic acid
Catalogue No.:PA 16 0091007
CAS :
193265-47-3
Molecular Formula : C15H14N4O4
Molecular Weight : 314.3


(S)-2-(4-(2-(2-Amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-methoxy-5-oxopentanoic acid
(S)-2-(4-(2-(2-Amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-methoxy-5-oxopentanoic acid
Catalogue No.:PA 16 0091008
CAS :
1265908-64-2
Molecular Formula : C21H23N5O6
Molecular Weight : 441.44


N2-(4-(2-(2-Amino-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-N5-(1,3-dihydroxy-2-(hydroxymethyl)propan-2-yl)-L-glutamine
N2-(4-(2-(2-Amino-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-N5-(1,3-dihydroxy-2-(hydroxymethyl)propan-2-yl)-L-glutamine
Catalogue No.:PA 16 0091011
CAS :
NA
Molecular Formula : C24H30N6O8
Molecular Weight : 530.54


(4-{2-[(RS)-2-Amino-4,6-dioxo-4,5,6,7-tetrahydro-3H -pyrrolo[2,3-d]pyrimidin-5-yl]ethyl}benzoyl)-l-glutamic acid
(4-{2-[(RS)-2-Amino-4,6-dioxo-4,5,6,7-tetrahydro-3H -pyrrolo[2,3-d]pyrimidin-5-yl]ethyl}benzoyl)-l-glutamic acid
Catalogue No.:PA 16 0091013
CAS :
1644287-27-3
Molecular Formula : C20H21N5O7
Molecular Weight : 443.42


Diethyl (4-(2-(2-(((dimethylamino)methylene)amino)-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-L-glutamate
Diethyl (4-(2-(2-(((dimethylamino)methylene)amino)-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-L-glutamate
Catalogue No.:PA 16 0091015
CAS :
1802552-05-1
Molecular Formula : C27H34N6O6
Molecular Weight : 538.61


(4-(3-(2-Amino-4-formamido-6-oxo-1,6-dihydropyrimidin-5-yl)-3-oxopropyl)benzoyl)-L-glutamic Acid
(4-(3-(2-Amino-4-formamido-6-oxo-1,6-dihydropyrimidin-5-yl)-3-oxopropyl)benzoyl)-L-glutamic Acid
Catalogue No.:PA 16 0091017
CAS :
1644286-35-0
Molecular Formula : C20H21N5O8
Molecular Weight : 459.42


Dimethyl (4-(2-(2-amino-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-L-glutamate 4-methylbenzenesulfonate
Dimethyl (4-(2-(2-amino-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-L-glutamate 4-methylbenzenesulfonate
Catalogue No.:PA 16 0091019
CAS :
1265908-56-2
Molecular Formula : C29H33N5O9S
Molecular Weight : 627.67


4,6-Dimethoxy-1,3,5-triazin-2-yl 4-(2-(2-amino-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoate
4,6-Dimethoxy-1,3,5-triazin-2-yl 4-(2-(2-amino-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoate
Catalogue No.:PA 16 0091020
CAS :
1209465-70-2
Molecular Formula : C20H19N7O5
Molecular Weight : 437.42


Methyl (S)-1-(4-(2-(2-amino-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-5-oxopyrrolidine-2-carboxylate
Methyl (S)-1-(4-(2-(2-amino-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-5-oxopyrrolidine-2-carboxylate
Catalogue No.:PA 16 0091026
CAS :
NA
Molecular Formula : C21H21N5O5
Molecular Weight : 423.43


(S)-1-(4-(2-(2-Amino-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-5-oxopyrrolidine-2-carboxylic acid
(S)-1-(4-(2-(2-Amino-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-5-oxopyrrolidine-2-carboxylic acid
Catalogue No.:PA 16 0091027
CAS :
NA
Molecular Formula : C20H19N5O5
Molecular Weight : 409.4


Dimethyl ((S)-2-(4-(2-(2-amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-methoxy-5-oxopentanoyl)-L-glutamate
Dimethyl ((S)-2-(4-(2-(2-amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-methoxy-5-oxopentanoyl)-L-glutamate
Catalogue No.:PA 16 0091030
CAS :
1265908-65-3
Molecular Formula : C28H34N6O9
Molecular Weight : 598.61


Dimethyl ((S)-4-(4-(2-(2-amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-methoxy-5-oxopentanoyl)-L-glutamate
Dimethyl ((S)-4-(4-(2-(2-amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-methoxy-5-oxopentanoyl)-L-glutamate
Catalogue No.:PA 16 0091031
CAS :
1265908-62-0
Molecular Formula : C28H34N6O9
Molecular Weight : 598.61


(4-(2-(2-Hydroxy-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-L-glutamic Acid
(4-(2-(2-Hydroxy-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-L-glutamic Acid
Catalogue No.:PA 16 0091033
CAS :
NA
Molecular Formula : C20H20N4O7
Molecular Weight : 428.4


(4-(2-(2-Amino-5-hydroxy-4,6-dioxo-4,5,6,7-tetrahydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-D-glutamic Acid
(4-(2-(2-Amino-5-hydroxy-4,6-dioxo-4,5,6,7-tetrahydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-D-glutamic Acid
Catalogue No.:PA 16 0091034
CAS :
NA
Molecular Formula : C20H21N5O8
Molecular Weight : 459.42


(4-(2-(2-amino-1,5,6-trihydroxy-4-oxo-4,5,6,7-tetrahydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-D-glutamic acid
(4-(2-(2-amino-1,5,6-trihydroxy-4-oxo-4,5,6,7-tetrahydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzoyl)-D-glutamic acid
Catalogue No.:PA 16 0091035
CAS :
1417656-72-4
Molecular Formula : C20H23N5O9
Molecular Weight : 477.43


Sodium (S)-4-(4-(2-(2-amino-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-ethoxy-5-oxopentanoate
Sodium (S)-4-(4-(2-(2-amino-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl)benzamido)-5-ethoxy-5-oxopentanoate
Catalogue No.:PA 16 0091036
CAS :
NA
Molecular Formula : C22H24N5NaO6
Molecular Weight : 477.45