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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

Estra-5(10),9(11)-diene-3,17-dione Cyclic 3,17-Bis(1,2-ethanediyl acetal) chemical structure

Estra-5(10),9(11)-diene-3,17-dione Cyclic 3,17-Bis(1,2-ethanediyl acetal)

CAS: 57905-07-4
Formula: C₂₂H₃₀O₄
MW: 358.5 g/mol

VQ-036687

Reference Standard

Estradiol 17-Hexanoate chemical structure

Estradiol 17-Hexanoate

CAS: 71764-18-6
Formula: C₂₄H₃₄O₃
MW: 370.5 g/mol

VQ-037094

Reference Standard

Estradiol 17-octanoate chemical structure

Estradiol 17-octanoate

CAS: 63042-22-8
Formula: C₂₆H₃₈O₃
MW: 398.6 g/mol

VQ-048294

Reference Standard

Estradiol 3-Enanthate chemical structure

Estradiol 3-Enanthate

CAS: 55540-97-1
Formula: C₂₅H₃₆O₃
MW: 384.6 g/mol

VQ-030593

Reference Standard

Estradiol 3-propyl ether chemical structure

Estradiol 3-propyl ether

CAS: 22034-63-5
Formula: C₂₁H₃₀O₂
MW: 314.5 g/mol

VQ-022564

Reference Standard

Estradiol 3-sulfate chemical structure

Estradiol 3-sulfate

CAS: 481-96-9
Formula: C₁₈H₂₄O₅S
MW: 352.4 g/mol

VQ-044943

Reference Standard

Estradiol Dicypionate chemical structure

Estradiol Dicypionate

CAS: 633-36-3
Formula: C₃₄H₄₈O₄
MW: 520.7 g/mol

VQ-037126

Reference Standard

Estradiol Dimer 3

Estradiol Dimer 3

CAS: 55870-08-1
Formula: C₂₂H₂₆O₃
MW: 338.44 g/mol

VQ-048295

Reference Standard

Estradiol Hexahydrobenzoate chemical structure

Estradiol Hexahydrobenzoate

CAS: 15140-27-9
Formula: C₂₅H₃₄O₃
MW: 382.5 g/mol

VQ-037125

Reference Standard

Estriol 3-sulfate chemical structure

Estriol 3-sulfate

CAS: 481-95-8
Formula: C₁₈H₂₄O₆S
MW: 368.4 g/mol

VQ-037097

Reference Standard

Estriol Impurity 2 chemical structure

Estriol Impurity 2

CAS: 1426679-35-7
Formula: C₂₅H₃₀O₄
MW: 394.5 g/mol

VQ-030572

Reference Standard

Estriol Impurity 3 chemical structure

Estriol Impurity 3

CAS: 58001-91-5
Formula: C₁₈H₂₄O₄
MW: 304.4 g/mol

VQ-030571

Reference Standard

Estrone 17-Ethylene Ketal chemical structure

Estrone 17-Ethylene Ketal

CAS: 900-83-4
Formula: C₂₀H₂₆O₃
MW: 314.4 g/mol

VQ-025649

Reference Standard

Estrone-3-Methyl Ether chemical structure

Estrone-3-Methyl Ether

CAS: 1624-62-0
Formula: C₁₉H₂₄O₂
MW: 284.4 g/mol

VQ-025640

Reference Standard

Etelcalcetide Impurity 1 chemical structure

Etelcalcetide Impurity 1

CAS: 1262781-26-9
Formula: C₃₈H₇₃N₂₁O₁₀S₂
MW: 1048.3 g/mol

VQ-048284

Reference Standard

Ethacrynic Acid Epoxide chemical structure

Ethacrynic Acid Epoxide

CAS: 27223-10-5
Formula: C₁₃H₁₂Cl₂O₅
MW: 319.13 g/mol

VQ-037115

Reference Standard

Ethacrynic Acid impurity E

Ethacrynic Acid impurity E

CAS: 55507-91-0
Formula: C₁₂H₁₀Cl₂O₄
MW: 289.11 g/mol

VQ-037116

Reference Standard

Ethacrynic Acid Impurity F Hydrochloride

Ethacrynic Acid Impurity F Hydrochloride

CAS: 1592-83-2
Formula: C₁₅H₂₀Cl₃NO₄
MW: 384.68 g/mol

VQ-030584

Reference Standard

Ethacrynic Acid Impurity G

Ethacrynic Acid Impurity G

CAS: 55507-81-8
Formula: C₁₄H₁₄Cl₂O₄
MW: 317.16 g/mol

VQ-037117

Reference Standard

Ethacrynic Acid Mercapturate (Mixture of diastereomers) chemical structure

Ethacrynic Acid Mercapturate (Mixture of diastereomers)

CAS: 54546-23-5
Formula: C₁₈H₂₁Cl₂NO₇S
MW: 466.3 g/mol

VQ-048287

Reference Standard

Ethane-1,2-diyl bis(4-phenylbutanoate) chemical structure

Ethane-1,2-diyl bis(4-phenylbutanoate)

CAS: 127324-78-1
Formula: C₂₂H₂₆O₄
MW: 354.4 g/mol

VQ-048542

Reference Standard

Ethanone, 1-(2',4'-difluoro[1,1'-biphenyl]-4-yl) chemical structure

Ethanone, 1-(2',4'-difluoro[1,1'-biphenyl]-4-yl)

CAS: 53591-79-0
Formula: C₁₄H₁₀F₂O
MW: 232.22 g/mol

VQ-036700

Reference Standard

Ethenoflucytosine chemical structure

Ethenoflucytosine

CAS: 1353100-75-0
Formula: C₆H₄FN₃O
MW: 153.11 g/mol

VQ-030777

Reference Standard

Ethinyl Estradiol Dimer Impurity 1 chemical structure

Ethinyl Estradiol Dimer Impurity 1

CAS: 303014-90-6
Formula: C₄₀H₄₆O₄
MW: 590.8 g/mol

VQ-030597

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