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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

4-(4-Morpholinyl)-1,2,5-Thiadiazol-3(2H)-one 1-Oxide Potassium Salt chemical structure

4-(4-Morpholinyl)-1,2,5-Thiadiazol-3(2H)-one 1-Oxide Potassium Salt

CAS: 79844-78-3
Formula: C₆H₈KN₃O₃S
MW: 241.31 g/mol

VQ-034916

Reference Standard

4-(4-Nitrophenyl) morpholine chemical structure

4-(4-Nitrophenyl) morpholine

CAS: 10389-51-2
Formula: C₁₀H₁₂N₂O₃
MW: 208.21 g/mol

VQ-038067

Reference Standard

4-(4-Nitrophenyl)Butanoic Acid chemical structure

4-(4-Nitrophenyl)Butanoic Acid

CAS: 5600-62-4
Formula: C₁₀H₁₁NO₄
MW: 209.2 g/mol

VQ-029740

Reference Standard

4-(4-Nitrophenyl)morpholin-3-one chemical structure

4-(4-Nitrophenyl)morpholin-3-one

CAS: 446292-04-2
Formula: C₁₀H₁₀N₂O₄
MW: 222.2 g/mol

VQ-033591

Reference Standard

4-(4-Nitrophenyl)sulfinylaniline chemical structure

4-(4-Nitrophenyl)sulfinylaniline

CAS: 5461-23-4
Formula: C₁₂H₁₀N₂O₃S
MW: 262.29 g/mol

VQ-039842

Reference Standard

4-(4-Oxobutyl)benzoic Acid Methyl Ester chemical structure

4-(4-Oxobutyl)benzoic Acid Methyl Ester

CAS: 106200-41-3
Formula: C₁₂H₁₄O₃
MW: 206.24 g/mol

VQ-041373

Reference Standard

4-(4-Pyridinyl)thiazole-2-thiol chemical structure

4-(4-Pyridinyl)thiazole-2-thiol

CAS: 77168-63-9
Formula: C₈H₆N₂S₂
MW: 194.3 g/mol

VQ-045361

Reference Standard

4-(4,4-Dimethyl-5-oxo-2-thioxo-1-imidazolidinyl)-2-trifluoromethylbenzonitril chemical structure

4-(4,4-Dimethyl-5-oxo-2-thioxo-1-imidazolidinyl)-2-trifluoromethylbenzonitril

CAS: 143782-28-9
Formula: C₁₃H₁₀F₃N₃OS
MW: 313.3 g/mol

VQ-048225

Reference Standard

4-(4,4-Dimethylthiochroman-6-yl)-2-methylbut-3-yn-2-ol

4-(4,4-Dimethylthiochroman-6-yl)-2-methylbut-3-yn-2-ol

CAS: 3026553-74-9
Formula: C₁₆H₂₀OS
MW: 260.39 g/mol

VQ-042375

Reference Standard

4-(4,5-Dichlorothiophen-2-yl)thiazol-2-amine chemical structure

4-(4,5-Dichlorothiophen-2-yl)thiazol-2-amine

CAS: 959042-70-7
Formula: C₇H₄Cl₂N₂S₂
MW: 251.2 g/mol

VQ-047494

Reference Standard

4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)morpholine chemical structure

4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)morpholine

CAS: 241483-00-1
Formula: C₉H₁₄N₄O₃
MW: 226.23 g/mol

VQ-036500

Reference Standard

4-(5-(2-Cyanopyridin-4-yl)-1H-1,2,4-triazol-3-yl)pyridine 1-oxide chemical structure

4-(5-(2-Cyanopyridin-4-yl)-1H-1,2,4-triazol-3-yl)pyridine 1-oxide

CAS: 577778-82-6
Formula: C₁₃H₈N₆O
MW: 264.24 g/mol

VQ-042614

Reference Standard

4-(5-Bromo-4-chlorothiophen-2-yl)thiazol-2-amine chemical structure

4-(5-Bromo-4-chlorothiophen-2-yl)thiazol-2-amine

CAS: 1534575-19-3
Formula: C₇H₄BrClN₂S₂
MW: 295.6 g/mol

VQ-029297

Reference Standard

4-(5-Chloro-2-thienyl)-1,3-thiazol-2-amine chemical structure

4-(5-Chloro-2-thienyl)-1,3-thiazol-2-amine

CAS: 123971-45-9
Formula: C₇H₅ClN₂S₂
MW: 216.7 g/mol

VQ-029299

Reference Standard

4-(5-Ethoxy-2,8-dimethyl-1,4-dihydro-1,6-naphthyridin-4-yl)-3-methoxybenzonitrile chemical structure

4-(5-Ethoxy-2,8-dimethyl-1,4-dihydro-1,6-naphthyridin-4-yl)-3-methoxybenzonitrile

CAS: 3046141-72-1
Formula: C₂₀H₂₁N₃O₂
MW: 335.4 g/mol

VQ-030743

Reference Standard

4-(5-Ethoxy-2,8-dimethyl-1,6-naphthyridin-4-yl)-3-methoxybenzonitrile chemical structure

4-(5-Ethoxy-2,8-dimethyl-1,6-naphthyridin-4-yl)-3-methoxybenzonitrile

CAS: 3078685-82-9
Formula: C₂₀H₁₉N₃O₂
MW: 333.4 g/mol

VQ-037280

Reference Standard

4-(5-Methyl-4-phenylisoxazol-3-yl)benzenesulfonamide chemical structure

4-(5-Methyl-4-phenylisoxazol-3-yl)benzenesulfonamide

CAS: 181696-12-8
Formula: C₁₆H₁₄N₂O₃S
MW: 314.4 g/mol

VQ-027391

Reference Standard

4-(6-Methoxynaphthalen-2-yl)benzoic Acid chemical structure

4-(6-Methoxynaphthalen-2-yl)benzoic Acid

CAS: 107430-57-9
Formula: C₁₈H₁₄O₃
MW: 278.3 g/mol

VQ-029027

Reference Standard

4-(6,8-Dibromo-1,4-dihydroquinazolin-3(2H)-yl)cyclohexan-1-ol

4-(6,8-Dibromo-1,4-dihydroquinazolin-3(2H)-yl)cyclohexan-1-ol

CAS: 1332582-28-1
Formula: C₁₄H₁₈Br₂N₂O
MW: 390.12 g/mol

VQ-035673

Reference Standard

4-(6,8-Dibromo-3(4H)-quinazolinyl)-cyclohexanol chemical structure

4-(6,8-Dibromo-3(4H)-quinazolinyl)-cyclohexanol

CAS: 1797894-71-3
Formula: C₁₄H₁₆Br₂N₂O
MW: 388.1 g/mol

VQ-024669

Reference Standard

4-(6'-Oxo-1'-phenyl-1',6'-dihydro-[2,3'-bipyridin]-5'-yl)benzonitrile chemical structure

4-(6'-Oxo-1'-phenyl-1',6'-dihydro-[2,3'-bipyridin]-5'-yl)benzonitrile

CAS: 380918-54-7
Formula: C₂₃H₁₅N₃O
MW: 349.4 g/mol

VQ-041410

Reference Standard

4-(7-(6-Cyano-5-(trifluoromethyl)pyridin-3-yl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]octan-5-yl)-N-(1-((6-cyano-5-(trifluoromethyl)pyridin-3-yl)carbamoyl)cyclobutyl)-2-fluoro-N-(3-fluoro-4-(methylcarbamoyl)phenyl)benzamide chemical structure

4-(7-(6-Cyano-5-(trifluoromethyl)pyridin-3-yl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]octan-5-yl)-N-(1-((6-cyano-5-(trifluoromethyl)pyridin-3-yl)carbamoyl)cyclobutyl)-2-fluoro-N-(3-fluoro-4-(methylcarbamoyl)phenyl)benzamide

CAS: 2894796-77-9
Formula: C₄₀H₂₇F₈N₉O₄S
MW: 881.8 g/mol

VQ-035748

Reference Standard

4-(7-(6-Cyano-5-(trifluoromethyl)pyridin-3-yl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]octan-5-yl)-N-methylbenzamide chemical structure

4-(7-(6-Cyano-5-(trifluoromethyl)pyridin-3-yl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]octan-5-yl)-N-methylbenzamide

CAS: 1332389-57-7
Formula: C₂₁H₁₆F₃N₅O₂S
MW: 459.4 g/mol

VQ-024306

Reference Standard

4-(Aminomethyl)pyridine chemical structure

4-(Aminomethyl)pyridine

CAS: 3731-53-1
Formula: C₆H₈N₂
MW: 108.14 g/mol

VQ-043870

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