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Impurities & Reference Standards

API Impurities

Source 1942 api impurities for research, QC and production, documented with COA and SDS.

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Reference Standard

Erythromycin Ethyl Fumarate chemical structure

Erythromycin Ethyl Fumarate

CAS: 122293-08-7
Formula: C₄₃H₇₃NO₁₆
MW: 860 g/mol

VQ-025603

Reference Standard

Erythromycin Ethyl Succinate chemical structure

Erythromycin Ethyl Succinate

CAS: 1264-62-6
Formula: C₄₃H₇₅NO₁₆
MW: 862.1 g/mol

VQ-030539

Reference Standard

Erythromycin Impurity 2

Erythromycin Impurity 2

CAS: 200802-92-2
Formula: C₃₈H₆₉NO₁₃
MW: 747.96 g/mol

VQ-044754

Reference Standard

Erythromycin Impurity E chemical structure

Erythromycin Impurity E

CAS: 857839-61-3
Formula: C₃₇H₆₅NO₁₂
MW: 715.9 g/mol

VQ-048260

Reference Standard

Erythromycin Impurity G chemical structure

Erythromycin Impurity G

CAS: 147702-49-6
Formula: C₃₉H₆₉NO₁₄
MW: 776 g/mol

VQ-030544

Reference Standard

Erythromycin Phthalyl Ester

Erythromycin Phthalyl Ester

CAS: 121057-86-1
Formula: C₄₅H₇₁NO₁₆
MW: 882.1 g/mol

VQ-045148

Reference Standard

Erythronolide B chemical structure

Erythronolide B

CAS: 3225-82-9
Formula: C₂₁H₃₈O₇
MW: 402.5 g/mol

VQ-037070

Reference Standard

Erythrosine chemical structure

CAS: 16423-68-0
Formula: C₂₀H₈I₄O₅
MW: 835.9 g/mol

VQ-019493

Reference Standard

Esaxerenone Diamine Impurity

Esaxerenone Diamine Impurity

CAS: 1632002-10-8
Formula: C₃₁H₂₈F₃N₃O₈S₂
MW: 691.69 g/mol

VQ-037077

Reference Standard

Escitalopram Acid impurity chemical structure

Escitalopram Acid impurity

CAS: 1133881-04-5
Formula: C₂₀H₂₂FNO₃
MW: 343.4 g/mol

VQ-030552

Reference Standard

Escitalopram Butyryl Impurity chemical structure

Escitalopram Butyryl Impurity

CAS: 1803244-58-7
Formula: C₂₅H₃₃FN₂O₂
MW: 412.5 g/mol

VQ-030553

Reference Standard

Escitalopram Impurity K chemical structure

Escitalopram Impurity K

CAS: 128196-02-1
Formula: C₂₀H₂₁FN₂O
MW: 324.4 g/mol

VQ-004928

Reference Standard

Escitalopram Impurity K (Oxalate Salt) chemical structure

Escitalopram Impurity K (Oxalate Salt)

CAS: 219861-53-7
Formula: C₂₂H₂₃FN₂O₅
MW: 414.4 g/mol

In stock

Reference Standard

Eslicarbazepine Propionate chemical structure

Eslicarbazepine Propionate

CAS: 952740-36-2
Formula: C₁₈H₁₈N₂O₃
MW: 310.3 g/mol

VQ-041262

Reference Standard

Esmolol Acid HCl chemical structure

Esmolol Acid HCl

CAS: 83356-60-9
Formula: C₁₅H₂₄ClNO₄
MW: 317.81 g/mol

VQ-044513

Reference Standard

Esmolol Dimer chemical structure

CAS: 98903-89-0
Formula: C₃₁H₄₆N₂O₇
MW: 558.7 g/mol

VQ-022558

Reference Standard

Esmolol Isopropyl Amine chemical structure

Esmolol Isopropyl Amine

CAS: 83356-59-6
Formula: C₁₈H₃₀N₂O₃
MW: 322.4 g/mol

VQ-025612

Reference Standard

Esomeprazole Impurity 11 chemical structure

Esomeprazole Impurity 11

CAS: 2924835-55-0
Formula: C₂₆H₃₀N₄O₃S
MW: 478.6 g/mol

VQ-048271

Reference Standard

Esomeprazole Impurity 12 chemical structure

Esomeprazole Impurity 12

CAS: 143016-68-6
Formula: C₈H₁₀Cl₃N
MW: 226.5 g/mol

VQ-037084

Reference Standard

Esomeprazole Impurity 2 chemical structure

Esomeprazole Impurity 2

CAS: 2512216-37-2
Formula: C₁₆H₁₇N₃O₂
MW: 283.32 g/mol

VQ-004930

Reference Standard

Esomeprazole Impurity 3

Esomeprazole Impurity 3

CAS: 2819805-13-3
Formula: C₃₂H₂₈N₆O₇
MW: 608.6 g/mol

VQ-030564

Reference Standard

Esomeprazole Impurity 9

Esomeprazole Impurity 9

CAS: 2586079-06-1
Formula: C₁₀H₁₅NO₅S
MW: 261.29 g/mol

VQ-048270

Reference Standard

Esomeprazole Impurity B chemical structure

Esomeprazole Impurity B

CAS: 110374-16-8
Formula: C₁₆H₁₇N₃O₂S
MW: 315.4 g/mol

In stock

Reference Standard

Esorubicin Hydrochloride chemical structure

Esorubicin Hydrochloride

CAS: 63950-06-1
Formula: C₂₇H₃₀ClNO₁₀
MW: 564 g/mol

VQ-030309

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