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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

Ezetimibe Ring-opening Dehydrate Impurity chemical structure

Ezetimibe Ring-opening Dehydrate Impurity

CAS: 1292292-63-7
Formula: C₂₄H₂₁F₂NO₃
MW: 409.4 g/mol

VQ-030658

Reference Standard

Ezetimibe Trihydroxy Impurity

Ezetimibe Trihydroxy Impurity

Formula: C₂₄H₂₃F₂NO₃
MW: 411.5 g/mol

In stock

Reference Standard

Ezetimibe Triol Impurity chemical structure

Ezetimibe Triol Impurity

CAS: 2363086-22-8
Formula: C₃₃H₃₀F₂N₂O₅
MW: 572.6 g/mol

VQ-004965

Reference Standard

Falcarindiol 3-acetate chemical structure

Falcarindiol 3-acetate

CAS: 111264-34-7
Formula: C₁₉H₂₆O₃
MW: 302.4 g/mol

VQ-040262

Reference Standard

Falcarinolone chemical structure

CAS: 18089-23-1
Formula: C₁₇H₂₂O₂
MW: 258.35 g/mol

VQ-040260

Reference Standard

Falcarinone chemical structure

CAS: 4117-11-7
Formula: C₁₇H₂₂O
MW: 242.36 g/mol

VQ-040261

Reference Standard

Famciclovir Malonate chemical structure

Famciclovir Malonate

CAS: 122497-20-5
Formula: C₁₂H₁₅N₅O₄
MW: 293.28 g/mol

VQ-030663

Reference Standard

Famotidine Adduct Impurity

Famotidine Adduct Impurity

CAS: 1994267-84-3
Formula: C₁₅H₁₉N₇O₂S₃
MW: 425.55 g/mol

VQ-030671

Reference Standard

Famotidine Cyclic Impurity chemical structure

Famotidine Cyclic Impurity

CAS: 2169078-41-3
Formula: C₃H₇N₃O₂S
MW: 149.17 g/mol

VQ-037198

Reference Standard

Faropenem Related Compound 4 chemical structure

Faropenem Related Compound 4

CAS: 106559-80-2
Formula: C₁₅H₁₉NO₅S
MW: 325.4 g/mol

VQ-037202

Reference Standard

Fazarabine chemical structure

CAS: 65886-71-7
Formula: C₈H₁₂N₄O₅
MW: 244.2 g/mol

VQ-035885

Reference Standard

Febuxostat (n-1) chemical structure

Febuxostat (n-1)

CAS: 1346238-13-8
Formula: C₂₄H₂₈N₂O₅S₂
MW: 488.6 g/mol

In stock

Reference Standard

Febuxostat (stage-I) chemical structure

Febuxostat (stage-I)

CAS: 208665-95-6
Formula: C₁₁H₁₂BrNO
MW: 254.12 g/mol

In stock

Reference Standard

Febuxostat (stage-II) chemical structure

Febuxostat (stage-II)

CAS: 208665-96-7
Formula: C₁₁H₁₄BrNOS
MW: 288.21 g/mol

In stock

Reference Standard

Febuxostat (stage-III) chemical structure

Febuxostat (stage-III)

CAS: 144060-96-8
Formula: C₁₇H₂₀BrNO₃S
MW: 398.3 g/mol

In stock

Reference Standard

Febuxostat (stage-IV)

Febuxostat (stage-IV)

Formula: C₁₈H₂₂N₂O₃S₂
MW: 378.51 g/mol

In stock

Reference Standard

Febuxostat 2-Butyl Isomer Ethyl Ester chemical structure

Febuxostat 2-Butyl Isomer Ethyl Ester

CAS: 2375033-35-3
Formula: C₁₈H₂₀N₂O₃S
MW: 344.4 g/mol

VQ-030693

Reference Standard

Febuxostat Amide Impurity chemical structure

Febuxostat Amide Impurity

CAS: 1239233-86-3
Formula: C₁₆H₁₈N₂O₄S
MW: 334.4 g/mol

VQ-025734

Reference Standard

Febuxostat Bromo Impurity chemical structure

Febuxostat Bromo Impurity

CAS: 144060-40-2
Formula: C₁₅H₁₆BrNO₃S
MW: 370.3 g/mol

VQ-025729

Reference Standard

Febuxostat Descarboxy Impurity chemical structure

Febuxostat Descarboxy Impurity

CAS: 1335202-60-2
Formula: C₁₅H₁₆N₂OS
MW: 272.4 g/mol

In stock

Reference Standard

Febuxostat Diacid Impurity chemical structure

Febuxostat Diacid Impurity

CAS: 1239233-87-4
Formula: C₁₆H₁₇NO₅S
MW: 335.4 g/mol

VQ-025733

Reference Standard

Febuxostat Dimethylthiazole Ethyl Ester Impurity chemical structure

Febuxostat Dimethylthiazole Ethyl Ester Impurity

CAS: 7210-77-7
Formula: C₈H₁₁NO₂S
MW: 185.25 g/mol

VQ-048344

Reference Standard

Febuxostat Dithiazole Acid Impurity chemical structure

Febuxostat Dithiazole Acid Impurity

CAS: 1330632-48-8
Formula: C₂₀H₂₀N₂O₅S₂
MW: 432.5 g/mol

In stock

Reference Standard

Febuxostat ethylester Amide impurity chemical structure

Febuxostat ethylester Amide impurity

CAS: 1346238-15-0
Formula: C₁₈H₂₂N₂O₄S
MW: 362.4 g/mol

VQ-048350

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