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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

rac-Ibuprofen Carboxymethyl Ester chemical structure

rac-Ibuprofen Carboxymethyl Ester

CAS: 1797132-75-2
Formula: C₁₅H₂₀O₄
MW: 264.32 g/mol

VQ-037633

Reference Standard

Rac-Ivabradine Hydrochloride

Rac-Ivabradine Hydrochloride

CAS: 1796933-38-4
Formula: C₂₇H₃₇ClN₂O₅
MW: 505.05 g/mol

VQ-031321

Reference Standard

rac-Lavandulal chemical structure

CAS: 75697-98-2
Formula: C₁₀H₁₆O
MW: 152.23 g/mol

VQ-048809

Reference Standard

rac-Lavandulol chemical structure

CAS: 58461-27-1
Formula: C₁₀H₁₈O
MW: 154.25 g/mol

VQ-037913

Reference Standard

rac-Mirabegron chemical structure

CAS: 1330277-46-7
Formula: C₂₁H₂₄N₄O₂S
MW: 396.5 g/mol

VQ-026723

Reference Standard

rac-N-Methyl-Laudanosine Iodide chemical structure

rac-N-Methyl-Laudanosine Iodide

CAS: 24948-17-2
Formula: C₂₂H₃₀INO₄
MW: 499.4 g/mol

VQ-029278

Reference Standard

Rac-Nebivolol chemical structure

CAS: 99200-09-6
Formula: C₂₂H₂₅F₂NO₄
MW: 405.4 g/mol

VQ-026838

Reference Standard

rac-O-Benzyl N-Benzyl Formoterol (Mixture of Diastereomers) chemical structure

rac-O-Benzyl N-Benzyl Formoterol (Mixture of Diastereomers)

CAS: 43229-70-5
Formula: C₃₃H₃₆N₂O₄
MW: 524.6 g/mol

VQ-025907

Reference Standard

rac-Praziquanamine chemical structure

rac-Praziquanamine

CAS: 61196-37-0
Formula: C₁₂H₁₄N₂O
MW: 202.25 g/mol

VQ-023535

Reference Standard

rac-Pregabalin chemical structure

CAS: 128013-69-4
Formula: C₈H₁₇NO₂
MW: 159.23 g/mol

VQ-027610

Reference Standard

Rac-Pregabalin Amide dimer

Rac-Pregabalin Amide dimer

CAS: 1486961-58-3
Formula: C₁₆H₃₂N₂O₃
MW: 300.44 g/mol

VQ-044152

Reference Standard

Rac-Rasagiline Mesylate impurity

Rac-Rasagiline Mesylate impurity

CAS: 2997444-40-1
Formula: C₁₃H₁₅NO₂S
MW: 249.33 g/mol

VQ-044681

Reference Standard

Rac-Rivastigmine chemical structure

Rac-Rivastigmine

CAS: 105601-20-5
Formula: C₁₄H₂₂N₂O₂
MW: 250.34 g/mol

VQ-044951

Reference Standard

Rac-Rosuvastatin tert-butyl ester chemical structure

Rac-Rosuvastatin tert-butyl ester

CAS: 1005003-79-1
Formula: C₂₆H₃₆FN₃O₆S
MW: 537.6 g/mol

VQ-033670

Reference Standard

Rac-Ruxolitinib 5,6-dihydroxyimpurity chemical structure

Rac-Ruxolitinib 5,6-dihydroxyimpurity

CAS: 1289219-47-1
Formula: C₁₇H₂₀N₆O₂
MW: 340.4 g/mol

VQ-044958

Reference Standard

Rac-Silodosin chemical structure

CAS: 160970-64-9
Formula: C₂₅H₃₂F₃N₃O₄
MW: 495.5 g/mol

VQ-028027

Reference Standard

rac-Sitagliptin chemical structure

rac-Sitagliptin

CAS: 823817-56-7
Formula: C₁₆H₁₅F₆N₅O
MW: 407.31 g/mol

VQ-033878

Reference Standard

rac-Tenofovir chemical structure

CAS: 107021-12-5
Formula: C₉H₁₄N₅O₄P
MW: 287.21 g/mol

VQ-034116

Reference Standard

rac-trans-4-Defluoro-4-ethoxy Paroxetine Hydrochloride chemical structure

rac-trans-4-Defluoro-4-ethoxy Paroxetine Hydrochloride

CAS: 1346597-97-4
Formula: C₂₁H₂₆ClNO₄
MW: 391.9 g/mol

VQ-027398

Reference Standard

rac-Valsartan Ethyl Ester chemical structure

rac-Valsartan Ethyl Ester

CAS: 1894176-41-0
Formula: C₂₆H₃₃N₅O₃
MW: 463.6 g/mol

VQ-042804

Reference Standard

rac,cis-Milnacipran Hydrochloride chemical structure

rac,cis-Milnacipran Hydrochloride

CAS: 165259-91-6
Formula: C₁₆H₂₅ClN₂O
MW: 296.83 g/mol

VQ-026699

Reference Standard

Racemate Methyldopa chemical structure

Racemate Methyldopa

CAS: 55-40-3
Formula: C₁₀H₁₃NO₄
MW: 211.21 g/mol

VQ-038372

Reference Standard

Racemic Dapoxetine chemical structure

Racemic Dapoxetine

CAS: 119356-76-2
Formula: C₂₁H₂₃NO
MW: 305.4 g/mol

VQ-030031

Reference Standard

Racemic Iptacopan

Racemic Iptacopan

CAS: 1644671-21-5
Formula: C₂₅H₃₀N₂O₄
MW: 422.5 g/mol

VQ-045485

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