amlodipine and its Impurities
Amlodipine is commonly used in the treatment of high blood pressure and angina. Amlodipine, initially approved by the FDA in 1987, is a popular antihypertensive drug belonging to the group of drugs called dihydropyridine calcium channel blockers. Reference standards of Amlodipine API, and its pharmacopeial, non pharmacopeial impurities, and stable isotopes are listed below.


2-((2-Aminoethoxy)methyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylic Acid
2-((2-Aminoethoxy)methyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylic Acid
Catalogue No.:PA 01 49550
CAS :
1821498-25-2
Molecular Formula : C17H19ClN2O5
Molecular Weight : 366.8


4-(2-Chlorophenyl)-1,4-dihydro-2-(hydroxymethyl)-6-methyl-3,5-pyridinedicarboxylic Acid 3-Ethyl 5-Methyl Ester
4-(2-Chlorophenyl)-1,4-dihydro-2-(hydroxymethyl)-6-methyl-3,5-pyridinedicarboxylic Acid 3-Ethyl 5-Methyl Ester
Catalogue No.:PA 01 49590
CAS :
79781-21-8
Molecular Formula : C18H20ClNO5
Molecular Weight : 365.81


3-Ethyl 5-Methyl 2-((2-acetamidoethoxy)methyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
3-Ethyl 5-Methyl 2-((2-acetamidoethoxy)methyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PA 01 49600
CAS :
93848-82-9
Molecular Formula : C22H27ClN2O6
Molecular Weight : 450.91


3-Ethyl 5-methyl 4-(2-chlorophenyl)-6-methyl-2-((2-((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)amino)ethoxy)methyl)-1,4-dihydropyridine-3,5-dicarboxylate
3-Ethyl 5-methyl 4-(2-chlorophenyl)-6-methyl-2-((2-((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)amino)ethoxy)methyl)-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PA 01 49610
CAS :
NA
Molecular Formula : C26H35ClN2O10
Molecular Weight : 571.02


Amlodipine Related Compound E (Diethyl 2-[(2-aminoethoxy)methyl]-4-(2-chlorophenyl)-6-methyl-1,4-di (1029556)
Amlodipine Related Compound E (Diethyl 2-[(2-aminoethoxy)methyl]-4-(2-chlorophenyl)-6-methyl-1,4-di (1029556)
Catalogue No.:PA USP1029556
CAS :
140171-65-9
Molecular Formula : NA
Molecular Weight : NA


Amlodipine Related Compound F (Dimethyl 2-[(2-aminoethoxy)methyl]-4-(2-chlorophenyl)-6-methyl-1,4-d (1029567)
Amlodipine Related Compound F (Dimethyl 2-[(2-aminoethoxy)methyl]-4-(2-chlorophenyl)-6-methyl-1,4-d (1029567)
Catalogue No.:PA USP1029567
CAS :
140171-66-0
Molecular Formula : NA
Molecular Weight : NA


Amlodipine Related Compound D (3-Ethyl 5-methyl 4-(2-chlorophenyl)-2-{[2-(1,3-dioxoisoindolin-2-yl) (1029545)
Amlodipine Related Compound D (3-Ethyl 5-methyl 4-(2-chlorophenyl)-2-{[2-(1,3-dioxoisoindolin-2-yl) (1029545)
Catalogue No.:PA USP1029545
CAS :
88150-62-3
Molecular Formula : NA
Molecular Weight : NA


Amlodipine Related Compound K (Ethyl 6-(2-chlorophenyl)-8-methyl-3,4,6,7-tetrahydro-2H-benzo[b][1,4 (1029614)
Amlodipine Related Compound K (Ethyl 6-(2-chlorophenyl)-8-methyl-3,4,6,7-tetrahydro-2H-benzo[b][1,4 (1029614)
Catalogue No.:PA USP1029614
CAS :
NA
Molecular Formula : NA
Molecular Weight : NA


Amlodipine Related Compound A (3-Ethyl, 5-methyl [2-(2-aminoethoxymethyl)-4-(2-chlorophenyl)-6-meth (1029512)
Amlodipine Related Compound A (3-Ethyl, 5-methyl [2-(2-aminoethoxymethyl)-4-(2-chlorophenyl)-6-meth (1029512)
Catalogue No.:PA USP1029512
CAS :
113994-41-5
Molecular Formula : NA
Molecular Weight : NA


Amlodipine Related Compound C (Dimethyl 4-(2-chlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dic (1029534)
Amlodipine Related Compound C (Dimethyl 4-(2-chlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dic (1029534)
Catalogue No.:PA USP1029534
CAS :
43067-01-2
Molecular Formula : NA
Molecular Weight : NA


Amlodipine Related Compound B (3-Ethyl 5-methyl 4-(2-chlorophenyl)-6-methyl-2-({2-[2-(methylcarbamo (1029523)
Amlodipine Related Compound B (3-Ethyl 5-methyl 4-(2-chlorophenyl)-6-methyl-2-({2-[2-(methylcarbamo (1029523)
Catalogue No.:PA USP1029523
CAS :
721958-72-1
Molecular Formula : NA
Molecular Weight : NA


3-Ethyl 5-methyl 2-((2-aminoethoxy)methyl)-4-(2-chlorophenyl)-6-methylpyridine-3,5-dicarboxylate
3-Ethyl 5-methyl 2-((2-aminoethoxy)methyl)-4-(2-chlorophenyl)-6-methylpyridine-3,5-dicarboxylate
Catalogue No.:PAI 01 003010
CAS :
113994-41-5
Molecular Formula : C20H23ClN2O5
Molecular Weight : 406.90


2-((Z)-tert-Butyl 2-(2-chlorobenzylidene)-4-(2-(1,3-dioxoisoindolin-2-yl)ethoxy)-3-oxobutanoate
2-((Z)-tert-Butyl 2-(2-chlorobenzylidene)-4-(2-(1,3-dioxoisoindolin-2-yl)ethoxy)-3-oxobutanoate
Catalogue No.:PAI 01 003020
CAS :
NA
Molecular Formula : C23H20ClNO6
Molecular Weight : 441.90


3-tert-Butyl 5-ethyl 4-(2-chlorophenyl)-2-((2-(1,3-dioxoisoindolin-2-yl)ethoxy)methyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
3-tert-Butyl 5-ethyl 4-(2-chlorophenyl)-2-((2-(1,3-dioxoisoindolin-2-yl)ethoxy)methyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PAI 01 003040
CAS :
NA
Molecular Formula : C13H16O2
Molecular Weight : 581.10


3-tert-Butyl 5-ethyl 2-((2-aminoethoxy)methyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
3-tert-Butyl 5-ethyl 2-((2-aminoethoxy)methyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PAI 01 003050
CAS :
NA
Molecular Formula : C23H31ClN2O5
Molecular Weight : 451.00


3-Benzyl 5-ethyl 4-(2-chlorophenyl)-2-((2-(1,3-dioxoisoindolin-2-yl)ethoxy)methyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
3-Benzyl 5-ethyl 4-(2-chlorophenyl)-2-((2-(1,3-dioxoisoindolin-2-yl)ethoxy)methyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PAI 01 003070
CAS :
NA
Molecular Formula : C34H31ClN2O7
Molecular Weight : 615.07


3-Benzyl 5-ethyl 2-((2-aminoethoxy)methyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
3-Benzyl 5-ethyl 2-((2-aminoethoxy)methyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PAI 01 003080
CAS :
NA
Molecular Formula : C26H29ClN2O5
Molecular Weight : 484.97


Diethyl 4-(2-chlorophenyl)-2-((2-(1,3-dioxoisoindolin-2-yl)ethoxy)methyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
Diethyl 4-(2-chlorophenyl)-2-((2-(1,3-dioxoisoindolin-2-yl)ethoxy)methyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PAI 01 003100
CAS :
140171-49-9
Molecular Formula : C29H29ClN2O7
Molecular Weight : 553

![(EZ)-2-[(2-Chlorophenyl)methylene]-4-[2-(1,3-dihyd PAI 01 003140](https://pharmaffiliates.com/public/pimages/PAI01003140.jpg)
(EZ)-2-[(2-Chlorophenyl)methylene]-4-[2-(1,3-dihydro-1,3-dioxo-2H-isoindol-2-yl)ethoxy]-3-oxobutanoic Acid Methyl Ester
(EZ)-2-[(2-Chlorophenyl)methylene]-4-[2-(1,3-dihydro-1,3-dioxo-2H-isoindol-2-yl)ethoxy]-3-oxobutanoic Acid Methyl Ester
Catalogue No.:PAI 01 003140
CAS :
NA
Molecular Formula : C22H18ClNO6
Molecular Weight : 427.83


4-(2-Chlorophenyl)-2-[[2-(1,3-dihydro-1,3-dioxo-2H-isoindol-2-yl)ethoxy]methyl]-1,4-dihydro-6-methyl-3,5-pyridinedicarboxylic Acid 3,5-Dimethyl Ester
4-(2-Chlorophenyl)-2-[[2-(1,3-dihydro-1,3-dioxo-2H-isoindol-2-yl)ethoxy]methyl]-1,4-dihydro-6-methyl-3,5-pyridinedicarboxylic Acid 3,5-Dimethyl Ester
Catalogue No.:PAI 01 003150
CAS :
140171-50-2
Molecular Formula : C27H25ClN2O7
Molecular Weight : 524.95


3-Ethyl 5-methyl 2-((2-((tert-butoxycarbonyl)amino)ethoxy)methyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
3-Ethyl 5-methyl 2-((2-((tert-butoxycarbonyl)amino)ethoxy)methyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PAI 01 003180
CAS :
143290-24-8
Molecular Formula : C25H33ClN2O7
Molecular Weight : 509


3-Ethyl 5-methyl 1-benzyl-4-(2-chlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate
3-Ethyl 5-methyl 1-benzyl-4-(2-chlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PAI 01 003200
CAS :
423771-19-1
Molecular Formula : C25H26ClNO4
Molecular Weight : 439.94


Ethyl 6-(2-chlorophenyl)-8-methyl-3,4,6,7-tetrahydro-2H-benzo[b][1,4]oxazine-5-carboxylate
Ethyl 6-(2-chlorophenyl)-8-methyl-3,4,6,7-tetrahydro-2H-benzo[b][1,4]oxazine-5-carboxylate
Catalogue No.:PA 01 49620
CAS :
1621516-91-3
Molecular Formula : C18H20ClNO3
Molecular Weight : 333.81


5-Ethyl 7-methyl 6-(2-chlorophenyl)-8-methyl-3,4,6,7-tetrahydro-2H-benzo[b][1,4]oxazine-5,7-dicarboxylate
5-Ethyl 7-methyl 6-(2-chlorophenyl)-8-methyl-3,4,6,7-tetrahydro-2H-benzo[b][1,4]oxazine-5,7-dicarboxylate
Catalogue No.:PA 01 50580
CAS :
496024-43-2
Molecular Formula : C20H22ClNO5
Molecular Weight : 391.85


3-Ethyl 5-methyl 2-(chloromethyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
3-Ethyl 5-methyl 2-(chloromethyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PAI 01 003270
CAS :
107812-86-2
Molecular Formula : C18H19Cl2NO4
Molecular Weight : 384.25


3-Ethyl 5-methyl 2-((2-bromoethoxy)methyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
3-Ethyl 5-methyl 2-((2-bromoethoxy)methyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PAI 01 003300
CAS :
2889481-02-9
Molecular Formula : C20H23BrClNO5
Molecular Weight : 472.76


Diethyl 4-(2-chlorophenyl)-2-((2-(2-((2-((4-(2-chlorophenyl)-3-(ethoxycarbonyl)-5-(methoxycarbonyl)-6-methyl-1,4-dihydropyridin-2-yl)methoxy)ethyl)carbamoyl)benzamido)ethoxy)methyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
Diethyl 4-(2-chlorophenyl)-2-((2-(2-((2-((4-(2-chlorophenyl)-3-(ethoxycarbonyl)-5-(methoxycarbonyl)-6-methyl-1,4-dihydropyridin-2-yl)methoxy)ethyl)carbamoyl)benzamido)ethoxy)methyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PA 01 49630
CAS :
NA
Molecular Formula : C49H54Cl2N4O12
Molecular Weight : 961.89

![2-[(Carboxymethoxy)methyl]-4-(2-chlorophenyl)-6-me PA 01 0491002](https://pharmaffiliates.com/public/pimages/PA010491002.jpg)
2-[(Carboxymethoxy)methyl]-4-(2-chlorophenyl)-6-methyl-3,5-Pyridinedicarboxylic acid 3-ethyl ester
2-[(Carboxymethoxy)methyl]-4-(2-chlorophenyl)-6-methyl-3,5-Pyridinedicarboxylic acid 3-ethyl ester
Catalogue No.:PA 01 0491002
CAS :
114018-75-6
Molecular Formula : C19H18ClNO7
Molecular Weight : 407.8


Amlodipine Di-Phthalimide Impurity
4-(2-Chlorophenyl)-6-[[2-(1,3-dihydro-1,3-dioxo-2h-isoindol-2-yl)ethoxy]methyl]-5-[4-(1,3-dihydro-1,3-dioxo-2h-isoindol-2-yl)-1-oxobutyl]-1,4-dihydro-2-methyl-3-pyridinecarboxylic acid methyl ester
Catalogue No.:PA 01 0491003
CAS :
223734-98-3
Molecular Formula : C37H32ClN3O8
Molecular Weight : 682.13

![2-[(2-Chlorophenyl)methylene]-4-[2-(1,3-dihydro-1, PA 01 0501000](https://pharmaffiliates.com/public/pimages/PA010501000.jpg)
2-[(2-Chlorophenyl)methylene]-4-[2-(1,3-dihydro-1,3-dioxo-2H-isoindol-2-yl)ethoxy]-3-oxobutanoic Acid Ethyl Ester
2-[(2-Chlorophenyl)methylene]-4-[2-(1,3-dihydro-1,3-dioxo-2H-isoindol-2-yl)ethoxy]-3-oxobutanoic Acid Ethyl Ester
Catalogue No.:PA 01 0501000
CAS :
400024-08-0
Molecular Formula : C23H20ClNO6
Molecular Weight : 441.86


5-Ethyl 7-methyl 6-(2-chlorophenyl)-8-methyl-3,4,6,8a-tetrahydro-2H-benzo[b][1,4]oxazine-5,7-dicarboxylate
5-Ethyl 7-methyl 6-(2-chlorophenyl)-8-methyl-3,4,6,8a-tetrahydro-2H-benzo[b][1,4]oxazine-5,7-dicarboxylate
Catalogue No.:PA 01 0501001
CAS :
949155-12-8
Molecular Formula : C20H22ClNO5
Molecular Weight : 391.85


9-Ethyl 7-methyl 8-(2-chlorophenyl)-6-methyl-3,4,8,9-tetrahydropyrido[2,1-c][1,4]oxazine-7,9-dicarboxylate
9-Ethyl 7-methyl 8-(2-chlorophenyl)-6-methyl-3,4,8,9-tetrahydropyrido[2,1-c][1,4]oxazine-7,9-dicarboxylate
Catalogue No.:PA 01 0501002
CAS :
949155-13-9
Molecular Formula : C20H22ClNO5
Molecular Weight : 391.85


5-Ethyl 7-methyl 6-(2-chlorophenyl)-8-methyl-3,4-dihydro-2H-benzo[b][1,4]oxazine-5,7-dicarboxylate
5-Ethyl 7-methyl 6-(2-chlorophenyl)-8-methyl-3,4-dihydro-2H-benzo[b][1,4]oxazine-5,7-dicarboxylate
Catalogue No.:PA 01 0501003
CAS :
2802443-91-8
Molecular Formula : C20H20ClNO5
Molecular Weight : 389.83


3-Ethyl 5-methyl 4-(2-chlorophenyl)-2-(ethoxymethyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
3-Ethyl 5-methyl 4-(2-chlorophenyl)-2-(ethoxymethyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PA 01 0501004
CAS :
2170104-02-4
Molecular Formula : C20H24ClNO5
Molecular Weight : 393.86


3-Ethyl 5-methyl 2-((2-aminoethoxy)methyl)-4-(2-chlorophenyl)-1,4-dihydropyridine-3,5-dicarboxylate
3-Ethyl 5-methyl 2-((2-aminoethoxy)methyl)-4-(2-chlorophenyl)-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PA 01 0501005
CAS :
2170111-18-7
Molecular Formula : C19H23ClN2O5
Molecular Weight : 394.85


3-Ethyl 5-methyl 4-(2-chlorophenyl)-6-methyl-2-(morpholin-2-yl)-1,4-dihydropyridine-3,5-dicarboxylate
3-Ethyl 5-methyl 4-(2-chlorophenyl)-6-methyl-2-(morpholin-2-yl)-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PA 01 0501007
CAS :
2387405-44-7
Molecular Formula : C21H25ClN2O5
Molecular Weight : 420.89


3-Ethyl 5-methyl (S)-2-((2-(1,3-dioxoisoindolin-2-yl)ethoxy)methyl)-6-methyl-4-phenyl-1,4-dihydropyridine-3,5-dicarboxylate
3-Ethyl 5-methyl (S)-2-((2-(1,3-dioxoisoindolin-2-yl)ethoxy)methyl)-6-methyl-4-phenyl-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PA 01 0491010
CAS :
NA
Molecular Formula : C28H28N2O7
Molecular Weight : 504.54


4-(2,3-Dichlorophenyl)-1,4-dihydro-2,6-dimethyl-3,5-pyridinedicarboxylic acid 3-(2-cyanoethyl) 5-methyl ester
4-(2,3-Dichlorophenyl)-1,4-dihydro-2,6-dimethyl-3,5-pyridinedicarboxylic acid 3-(2-cyanoethyl) 5-methyl ester
Catalogue No.:PA 01 0501008
CAS :
110962-94-2
Molecular Formula : C19H18Cl2N2O4
Molecular Weight : 409.26


Ethyl 2-((2-Chlorophenyl)(hydroxy)methyl)-4-(2-(1,3-dioxoisoindolin-2-yl)ethoxy)-3-oxobutanoate
Ethyl 2-((2-Chlorophenyl)(hydroxy)methyl)-4-(2-(1,3-dioxoisoindolin-2-yl)ethoxy)-3-oxobutanoate
Catalogue No.:PA 01 0501009
CAS :
NA
Molecular Formula : C23H22ClNO7
Molecular Weight : 459.88


3-Ethyl 5-methyl 4-(2-chlorophenyl)-6-methyl-2-((2-(phenylsulfonamido)ethoxy)methyl)-1,4-dihydropyridine-3,5-dicarboxylate
3-Ethyl 5-methyl 4-(2-chlorophenyl)-6-methyl-2-((2-(phenylsulfonamido)ethoxy)methyl)-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PA 01 0501010
CAS :
2832589-38-3
Molecular Formula : C26H29ClN2O7S
Molecular Weight : 549.04


2-((2-((4-(2-Chlorophenyl)-3-(ethoxycarbonyl)-5-(methoxycarbonyl)-6-methyl-1,4-dihydropyridin-2-yl)methoxy)ethyl)amino)-4-methoxy-4-oxobutanoic acid
2-((2-((4-(2-Chlorophenyl)-3-(ethoxycarbonyl)-5-(methoxycarbonyl)-6-methyl-1,4-dihydropyridin-2-yl)methoxy)ethyl)amino)-4-methoxy-4-oxobutanoic acid
Catalogue No.:PA 01 0501012
CAS :
NA
Molecular Formula : C25H31ClN2O9
Molecular Weight : 538.98


3-Ethyl 5-methyl 4-(2-chlorophenyl)-2-(methoxymethyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
3-Ethyl 5-methyl 4-(2-chlorophenyl)-2-(methoxymethyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
Catalogue No.:PA 01 0491011
CAS :
2170104-51-3
Molecular Formula : C19H22ClNO5
Molecular Weight : 379.84


Methyl 6-((2-aminoethoxy)methyl)-5-(ethoxymethyl)-4-(4-hydroxyphenyl)-2-methylnicotinate Hydrochloride
Methyl 6-((2-aminoethoxy)methyl)-5-(ethoxymethyl)-4-(4-hydroxyphenyl)-2-methylnicotinate Hydrochloride
Catalogue No.:PA 01 0491017
CAS :
NA
Molecular Formula : C20H27ClN2O5
Molecular Weight : 410.9