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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

Fosaprepitant Enantiomer (Dimeglumine) chemical structure

Fosaprepitant Enantiomer (Dimeglumine)

CAS: 1523569-87-0
Formula: C₃₇H₅₆F₇N₆O₁₆P
MW: 1004.8 g/mol

VQ-030873

Reference Standard

Fosaprepitant Ester Impurity

Fosaprepitant Ester Impurity

CAS: 1803189-49-2
Formula: C₂₄H₂₅F₇N₄O₄
MW: 566.48 g/mol

VQ-030871

Reference Standard

Fosaprepitant Impurity 1

Fosaprepitant Impurity 1

CAS: 1185503-00-7
Formula: C₂₃H₂₂F₇N₄O₆P
MW: 614.4 g/mol

VQ-043798

Reference Standard

Fosaprepitant Impurity 10 chemical structure

Fosaprepitant Impurity 10

CAS: 172673-19-7
Formula: C₂₃H₂₂F₇N₄O₆P
MW: 614.4 g/mol

VQ-048464

Reference Standard

Foscarnet Sodium Hexahydrate chemical structure

Foscarnet Sodium Hexahydrate

CAS: 34156-56-4
Formula: CH₁₂Na₃O₁₁P
MW: 300.04 g/mol

VQ-030874

Reference Standard

Fosfomycin (R)-1-phenethylamine chemical structure

Fosfomycin (R)-1-phenethylamine

CAS: 25383-07-7
Formula: C₁₁H₁₈NO₄P
MW: 259.24 g/mol

VQ-048467

Reference Standard

Fosfomycin Diastereomer 1 chemical structure

Fosfomycin Diastereomer 1

CAS: 27357-50-2
Formula: C₃H₇O₄P
MW: 138.06 g/mol

VQ-030877

Reference Standard

Fosfomycin Diastereomer 2 chemical structure

Fosfomycin Diastereomer 2

CAS: 45629-00-3
Formula: C₃H₇O₄P
MW: 138.06 g/mol

VQ-025919

Reference Standard

Fosfomycin enantiomer chemical structure

Fosfomycin enantiomer

CAS: 25030-76-6
Formula: C₃H₇O₄P
MW: 138.06 g/mol

VQ-037427

Reference Standard

Fosravuconazole Amide Impurity

Fosravuconazole Amide Impurity

CAS: 942415-34-1
Formula: C₂₇H₃₀F₂N₅O₆PS
MW: 621.6 g/mol

VQ-025923

Reference Standard

Fosravuconazole L-Lysine Ethanolate chemical structure

Fosravuconazole L-Lysine Ethanolate

CAS: 914361-45-8
Formula: C₃₁H₄₀F₂N₇O₈PS
MW: 739.7 g/mol

VQ-030885

Reference Standard

Fostemsavir bromophenylsulfonyl Impurity chemical structure

Fostemsavir bromophenylsulfonyl Impurity

CAS: 1449413-27-7
Formula: C₂₀H₁₇BrN₂O₆S₂
MW: 525.4 g/mol

VQ-037435

Reference Standard

Fostemsavir Ter-Butyl Phosphate chemical structure

Fostemsavir Ter-Butyl Phosphate

CAS: 864953-38-8
Formula: C₃₃H₄₂N₇O₈P
MW: 695.7 g/mol

VQ-037436

Reference Standard

Framycetin sulfate chemical structure

Framycetin sulfate

CAS: 28002-70-2
Formula: C₂₃H₄₈N₆O₁₇S
MW: 712.7 g/mol

VQ-026864

Reference Standard

Frovatriptan Impurity 28 chemical structure

Frovatriptan Impurity 28

CAS: 147009-31-2
Formula: C₁₃H₁₂N₂O
MW: 212.25 g/mol

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Reference Standard

Fruquintinib 2-Formyl-benzofuran Impurity

Fruquintinib 2-Formyl-benzofuran Impurity

CAS: 2858589-70-3
Formula: C₂₁H₁₇N₃O₆
MW: 407.4 g/mol

VQ-037445

Reference Standard

Fruquintinib Benzofuran Acid Impurity chemical structure

Fruquintinib Benzofuran Acid Impurity

CAS: 103986-33-0
Formula: C₁₁H₁₀O₄
MW: 206.19 g/mol

VQ-030893

Reference Standard

Fruquintinib chloro impurity chemical structure

Fruquintinib chloro impurity

CAS: 13790-39-1
Formula: C₁₀H₉ClN₂O₂
MW: 224.64 g/mol

VQ-043703

Reference Standard

Fruquintinib Impurity 12 chemical structure

Fruquintinib Impurity 12

CAS: 574745-97-4
Formula: C₉H₇ClN₂O₂
MW: 210.62 g/mol

VQ-037443

Reference Standard

Fruquintinib Impurity 13 chemical structure

Fruquintinib Impurity 13

CAS: 263400-68-6
Formula: C₉H₇ClN₂O₂
MW: 210.62 g/mol

VQ-048473

Reference Standard

Fulvestrant Impurity 14

Fulvestrant Impurity 14

CAS: 1428539-56-3
Formula: C₃₁H₄₅BrO₄
MW: 561.59 g/mol

VQ-048477

Reference Standard

Fulvestrant Impurity 17

Fulvestrant Impurity 17

CAS: 66263-02-3
Formula: C₂₀H₂₆O₃
MW: 314.42 g/mol

VQ-048478

Reference Standard

Fulvestrant Impurity 19 chemical structure

Fulvestrant Impurity 19

CAS: 6728-21-8
Formula: C₄H₈O₃S
MW: 136.17 g/mol

VQ-048479

Reference Standard

Fulvestrant Impurity 21 chemical structure

Fulvestrant Impurity 21

CAS: 23433-07-0
Formula: C₉H₂₀O₂
MW: 160.25 g/mol

VQ-048480

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