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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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COA + SDSwith every lot

Reference Standard

Cetirizine Lactose Ester Impurity

Cetirizine Lactose Ester Impurity

Formula: C₃₃H₄₅ClN₂O₁₃
MW: 713.17 g/mol

VQ-004634

Reference Standard

Cetirizine Methyl Ester Impurity chemical structure

Cetirizine Methyl Ester Impurity

CAS: 83881-46-3
Formula: C₂₂H₂₇ClN₂O₃
MW: 402.9 g/mol

In stock

Reference Standard

Cetirizine Phenylsulfone chemical structure

Cetirizine Phenylsulfone

CAS: 1391052-52-0
Formula: C₂₃H₂₃ClN₂O₂S
MW: 427 g/mol

VQ-022135

Reference Standard

Cetirizine S-Isomer chemical structure

Cetirizine S-Isomer

CAS: 130018-89-2
Formula: C₂₁H₂₆Cl₂N₂O₃
MW: 425.3 g/mol

VQ-031521

Reference Standard

Cevimeline Thiol Impurity chemical structure

Cevimeline Thiol Impurity

CAS: 107220-26-8
Formula: C₈H₁₅NOS
MW: 173.28 g/mol

VQ-024917

Reference Standard

Cevimeline trans-Isomer chemical structure

Cevimeline trans-Isomer

CAS: 1462862-74-3
Formula: C₂₀H₃₈Cl₂N₂O₃S₂
MW: 489.6 g/mol

VQ-036230

Reference Standard

Charantin

CAS: 57126-62-2
Formula: C₇₀H₁₁₈O₁₂
MW: 1151.68 g/mol

VQ-040281

Reference Standard

Chenodeoxycholic Acid Methyl Ester chemical structure

Chenodeoxycholic Acid Methyl Ester

CAS: 3057-04-3
Formula: C₂₅H₄₂O₄
MW: 406.6 g/mol

VQ-036232

Reference Standard

Chicoric Acid chemical structure

CAS: 70831-56-0
Formula: C₂₂H₁₈O₁₂
MW: 474.4 g/mol

VQ-036289

Reference Standard

Chlordiazepoxide oxaziridine chemical structure

Chlordiazepoxide oxaziridine

CAS: 17953-23-0
Formula: C₁₆H₁₄ClN₃O
MW: 299.75 g/mol

VQ-044830

Reference Standard

Chlorhexidine Digluconate Impurity N chemical structure

Chlorhexidine Digluconate Impurity N

CAS: 152504-10-4
Formula: C₁₅H₂₅ClN₈
MW: 352.86 g/mol

VQ-021129

Reference Standard

Chlormadinone Acetate (Reference Standard) chemical structure

Chlormadinone Acetate (Reference Standard)

CAS: 302-22-7
Formula: C₂₃H₂₉ClO₄
MW: 404.9 g/mol

In stock

Reference Standard

Chlormadinone Impurity 1

Chlormadinone Impurity 1

CAS: 2133-50-8
Formula: C₂₃H₃₀O₅
MW: 386.48 g/mol

VQ-047754

Reference Standard

Chlormethyl 17a-ethoxycarbonyloxy-3-oxoandrosta-1,4,9(11)-triene-17beta-carboxylate chemical structure

Chlormethyl 17a-ethoxycarbonyloxy-3-oxoandrosta-1,4,9(11)-triene-17beta-carboxylate

CAS: 207670-55-1
Formula: C₂₄H₂₉ClO₆
MW: 448.9 g/mol

VQ-031654

Reference Standard

Chloro Cephalexin chemical structure

Chloro Cephalexin

CAS: 22039-59-4
Formula: C₁₆H₁₆ClN₃O₄S
MW: 381.8 g/mol

VQ-021128

Reference Standard

Chloro Fluticasone Furoate chemical structure

Chloro Fluticasone Furoate

CAS: 1374153-88-4
Formula: C₂₇H₂₉ClF₂O₆S
MW: 555 g/mol

VQ-025883

Reference Standard

Chloro Propanyl Dimer Impurity of Ibrutinib (PCI-7547) chemical structure

Chloro Propanyl Dimer Impurity of Ibrutinib (PCI-7547)

CAS: 2031255-23-7
Formula: C₅₀H₄₈N₁₂O₄
MW: 881 g/mol

In stock

Reference Standard

Chloro Sofosbuvir chemical structure

Chloro Sofosbuvir

CAS: 1496552-51-2
Formula: C₂₂H₂₉ClN₃O₉P
MW: 545.9 g/mol

VQ-023776

Reference Standard

Chloro Trilaciclib Impurity chemical structure

Chloro Trilaciclib Impurity

CAS: 1374635-90-1
Formula: C₁₄H₁₅ClN₄O
MW: 290.75 g/mol

VQ-045358

Reference Standard

Chloro(1,5-cyclooctadiene)rhodium(I)dimer chemical structure

Chloro(1,5-cyclooctadiene)rhodium(I)dimer

CAS: 12092-47-6
Formula: C₁₆H₂₄Cl₂Rh₂-2
MW: 493.1 g/mol

VQ-052342

Reference Standard

Chlorodenafil chemical structure

CAS: 1058653-74-9
Formula: C₁₉H₂₁ClN₄O₃
MW: 388.8 g/mol

VQ-043586

Reference Standard

Chlorodiphenylmethane chemical structure

Chlorodiphenylmethane

CAS: 90-99-3
Formula: C₁₃H₁₁Cl
MW: 202.68 g/mol

VQ-032701

Reference Standard

Chlorofurantoin

Chlorofurantoin

CAS: 2620835-29-0
Formula: C₈H₆ClN₃O₃
MW: 227.6 g/mol

VQ-038671

Reference Standard

Chloromethyl Diethylcarbamate chemical structure

Chloromethyl Diethylcarbamate

CAS: 133217-92-2
Formula: C₆H₁₂ClNO₂
MW: 165.62 g/mol

VQ-042420

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