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Impurities & Reference Standards

API Impurities

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

14,252products

1,516in stock

COA + SDSwith every lot

Reference Standard

Citalopram Alkene Dimer Chloride chemical structure

Citalopram Alkene Dimer Chloride

CAS: 1370643-27-8
Formula: C₄₀H₄₁ClF₂N₄O
MW: 667.2 g/mol

VQ-025000

Reference Standard

Citalopram Carboxylic Acid Impurity chemical structure

Citalopram Carboxylic Acid Impurity

CAS: 440121-09-5
Formula: C₂₀H₂₂FNO₃
MW: 343.4 g/mol

In stock

Reference Standard

Citalopram Descyano Impurity chemical structure

Citalopram Descyano Impurity

CAS: 390817-87-5
Formula: C₁₉H₁₆F₃N₃O₄
MW: 407.3 g/mol

VQ-035010

Reference Standard

Citalopram Diol-Desfluoro Impurity chemical structure

Citalopram Diol-Desfluoro Impurity

CAS: 1187671-15-3
Formula: C₂₀H₂₄N₂O₂
MW: 324.4 g/mol

VQ-029828

Reference Standard

Citalopram Impurity A chemical structure

Citalopram Impurity A

CAS: 64372-56-1
Formula: C₂₀H₂₃FN₂O₂
MW: 342.4 g/mol

VQ-004652

Reference Standard

Citalopram Related Compound II chemical structure

Citalopram Related Compound II

CAS: 488787-59-3
Formula: C₂₀H₂₃FN₂O₂
MW: 342.4 g/mol

In stock

Reference Standard

Citicoline IP Impurity C chemical structure

Citicoline IP Impurity C

CAS: 52448-10-9
Formula: C₁₀H₁₆N₃O₈P
MW: 337.22 g/mol

VQ-022291

Reference Standard

Citicoline IP Impurity D chemical structure

Citicoline IP Impurity D

CAS: 76742-17-1
Formula: C₁₃H₂₁N₄O₈P
MW: 392.3 g/mol

VQ-036351

Reference Standard

Citicoline IP Impurity D (Dicyclohexylcarboxamidine Salt) chemical structure

Citicoline IP Impurity D (Dicyclohexylcarboxamidine Salt)

CAS: 76742-18-2
Formula: C₃₀H₅₂N₇O₉P
MW: 685.7 g/mol

VQ-035264

Reference Standard

Citraconic acid chemical structure

Citraconic acid

CAS: 498-23-7
Formula: C₅H₆O₄
MW: 130.1 g/mol

VQ-032710

Reference Standard

Cladribine 5′-(4-methylbenzoate) chemical structure

Cladribine 5′-(4-methylbenzoate)

CAS: 152463-97-3
Formula: C₁₈H₁₈ClN₅O₄
MW: 403.8 g/mol

VQ-036353

Reference Standard

Cladribine Mono Benzoate Impurity chemical structure

Cladribine Mono Benzoate Impurity

CAS: 152463-98-4
Formula: C₁₈H₁₈ClN₅O₄
MW: 403.8 g/mol

VQ-029834

Reference Standard

Clarithromycin_EDO

Clarithromycin_EDO

CAS: 119665-78-0
Formula: C₄₈H₉₄N₂O₁₄Si₂
MW: 979.44 g/mol

VQ-030540

Reference Standard

Clavulanate Impurity 2 chemical structure

Clavulanate Impurity 2

CAS: 295796-12-2
Formula: C₆H₁₈Cl₂N₂O
MW: 205.12 g/mol

VQ-044161

Reference Standard

Clavulanic Acid Impurity 7 DiHCl chemical structure

Clavulanic Acid Impurity 7 DiHCl

CAS: 75804-28-3
Formula: C₆H₁₈Cl₂N₂
MW: 189.12 g/mol

VQ-035207

Reference Standard

Clebopride Malate chemical structure

Clebopride Malate

CAS: 57645-91-7
Formula: C₂₄H₃₀ClN₃O₇
MW: 508 g/mol

VQ-036357

Reference Standard

Clemastine Fumarate Impurity B chemical structure

Clemastine Fumarate Impurity B

CAS: 61771-18-4
Formula: C₂₁H₂₆ClNO
MW: 343.9 g/mol

VQ-036359

Reference Standard

Cleomycin A2 chemical structure

CAS: 754137-61-6
Formula: C₅₆H₈₃N₁₇O₂₁S₃
MW: 1426.6 g/mol

VQ-047603

Reference Standard

Clethodim Bis oxime impurity

Clethodim Bis oxime impurity

CAS: 111031-48-2
Formula: C₁₇H₂₆Cl₂N₂O₂S
MW: 393.37 g/mol

VQ-036369

Reference Standard

Clethodim Impurity 2 chemical structure

Clethodim Impurity 2

CAS: 29560-84-7
Formula: C₃H₅ClO
MW: 92.52 g/mol

VQ-047816

Reference Standard

Clethodim Impurity 6

Clethodim Impurity 6

CAS: 111031-45-9
Formula: C₂₃H₃₄Cl₃N₃O₃S
MW: 538.96 g/mol

VQ-047819

Reference Standard

Clethodim Oxazole chemical structure

Clethodim Oxazole

CAS: 111059-49-5
Formula: C₁₄H₂₁NO₂S
MW: 267.39 g/mol

VQ-036364

Reference Standard

Clevidipine Butyrate chemical structure

Clevidipine Butyrate

CAS: 167221-71-8
Formula: C₂₁H₂₃Cl₂NO₆
MW: 456.3 g/mol

VQ-025009

Reference Standard

Clevidipine butyrate Impurity CLE 04

Clevidipine butyrate Impurity CLE 04

CAS: 1346550-33-1
Formula: C₁₆H₁₆Cl₂O₅
MW: 359.2 g/mol

VQ-021191

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