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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-((7-Chloro-2-methoxybenzo[b][1,5]naphthyridin-10-yl)amino)phenol chemical structure

4-((7-Chloro-2-methoxybenzo[b][1,5]naphthyridin-10-yl)amino)phenol

CAS: 81935-60-6
Formula: C₁₉H₁₄ClN₃O₂
MW: 351.8 g/mol

VQ-044926

Reference Standard

4-((Methylsulfonyl)oxy)butyl Acetate chemical structure

4-((Methylsulfonyl)oxy)butyl Acetate

CAS: 19859-00-8
Formula: C₇H₁₄O₅S
MW: 210.25 g/mol

VQ-021941

Reference Standard

4-((Tert-Butoxycarbonyl)amino)benzoic acid chemical structure

4-((Tert-Butoxycarbonyl)amino)benzoic acid

CAS: 66493-39-8
Formula: C₁₂H₁₅NO₄
MW: 237.25 g/mol

VQ-038449

Reference Standard

4-((tert-Butoxycarbonyl)amino)piperidine-4-carboxylic acid chemical structure

4-((tert-Butoxycarbonyl)amino)piperidine-4-carboxylic acid

CAS: 252720-31-3
Formula: C₁₁H₂₀N₂O₄
MW: 244.29 g/mol

VQ-024754

Reference Standard

4-([1,2,4]Triazolo[1,5-a]pyridin-7-yloxy)-3-methylaniline chemical structure

4-([1,2,4]Triazolo[1,5-a]pyridin-7-yloxy)-3-methylaniline

CAS: 937263-71-3
Formula: C₁₃H₁₂N₄O
MW: 240.26 g/mol

VQ-034470

Reference Standard

4-(1-(2,3-Dimethylphenyl)vinyl)-1-trityl-1H-imidazole chemical structure

4-(1-(2,3-Dimethylphenyl)vinyl)-1-trityl-1H-imidazole

CAS: 1375519-40-6
Formula: C₃₂H₂₈N₂
MW: 440.6 g/mol

VQ-049026

Reference Standard

4-(1-(2,4-Diaminopteridin-6-yl)pent-4-yn-2-yl)benzoic Acid chemical structure

4-(1-(2,4-Diaminopteridin-6-yl)pent-4-yn-2-yl)benzoic Acid

CAS: 146464-93-9
Formula: C₁₈H₁₆N₆O₂
MW: 348.4 g/mol

VQ-027563

Reference Standard

4-(1-Bromoethyl)-5-fluoropyrimidine chemical structure

4-(1-Bromoethyl)-5-fluoropyrimidine

CAS: 188416-47-9
Formula: C₆H₆BrFN₂
MW: 205.03 g/mol

VQ-042941

Reference Standard

4-(1-Carboxyethyl)-δ-oxo-benzenehexanoic Acid chemical structure

4-(1-Carboxyethyl)-δ-oxo-benzenehexanoic Acid

CAS: 1091621-61-2
Formula: C₁₅H₁₈O₅
MW: 278.3 g/mol

VQ-026530

Reference Standard

4-(1-Cyclohexyl-1H-tetrazol-5-yl)butan-1-ol chemical structure

4-(1-Cyclohexyl-1H-tetrazol-5-yl)butan-1-ol

CAS: 934533-78-5
Formula: C₁₁H₂₀N₄O
MW: 224.3 g/mol

VQ-028944

Reference Standard

4-(1-Methoxy-1-methylethyl)-2-propyl-1H-imidazole-5-carboxylic Acid Ethyl Ester chemical structure

4-(1-Methoxy-1-methylethyl)-2-propyl-1H-imidazole-5-carboxylic Acid Ethyl Ester

CAS: 1092980-84-1
Formula: C₁₃H₂₂N₂O₃
MW: 254.33 g/mol

VQ-023328

Reference Standard

4-(1-Methoxy-2-(methylamino)ethyl)benzene-1,2-diol chemical structure

4-(1-Methoxy-2-(methylamino)ethyl)benzene-1,2-diol

CAS: 2947-02-6
Formula: C₁₀H₁₅NO₃
MW: 197.23 g/mol

VQ-024150

Reference Standard

4-(1-Methyl-1H-indol-3-yl)pyrimidin-2-amine chemical structure

4-(1-Methyl-1H-indol-3-yl)pyrimidin-2-amine

CAS: 199865-36-6
Formula: C₁₃H₁₂N₄
MW: 224.26 g/mol

VQ-049364

Reference Standard

4-(1-Methyl-4-piperidinyl)-4H-benzo[4,5]cyclohepta[1,2-b]thiophene-4-ol chemical structure

4-(1-Methyl-4-piperidinyl)-4H-benzo[4,5]cyclohepta[1,2-b]thiophene-4-ol

CAS: 4506-57-4
Formula: C₁₉H₂₁NOS
MW: 311.4 g/mol

VQ-037822

Reference Standard

4-(1-Methyl-5-nitro-1H-benzo[d]imidazol-2-yl)butanoic Acid chemical structure

4-(1-Methyl-5-nitro-1H-benzo[d]imidazol-2-yl)butanoic Acid

CAS: 31349-48-1
Formula: C₁₂H₁₃N₃O₄
MW: 263.25 g/mol

VQ-029381

Reference Standard

4-(1-Methylpyridin-1-ium-4-yl) thiazole-2-thiolate chemical structure

4-(1-Methylpyridin-1-ium-4-yl) thiazole-2-thiolate

CAS: 1427207-46-2
Formula: C₉H₈N₂S₂
MW: 208.3 g/mol

VQ-024870

Reference Standard

4-(1,1-Dimethyl-2-oxo-1,2-dihydro-3H-benzo[e]indol-3-yl)butane-1-sulfonic Acid chemical structure

4-(1,1-Dimethyl-2-oxo-1,2-dihydro-3H-benzo[e]indol-3-yl)butane-1-sulfonic Acid

CAS: 906772-02-9
Formula: C₁₈H₂₁NO₄S
MW: 347.4 g/mol

VQ-031202

Reference Standard

4-(1,2,4-Oxadiazol-3-yl)aniline chemical structure

4-(1,2,4-Oxadiazol-3-yl)aniline

CAS: 59908-70-2
Formula: C₈H₇N₃O
MW: 161.16 g/mol

VQ-047377

Reference Standard

4-(1,3,2-Dioxaborinan-2-yl)benzonitrile chemical structure

4-(1,3,2-Dioxaborinan-2-yl)benzonitrile

CAS: 152846-62-3
Formula: C₁₀H₁₀BNO₂
MW: 187 g/mol

VQ-041408

Reference Standard

4-(1a,10b-Dihydro-6H-dibenzo[3,4:6,7]cyclohepta[1,2-b]oxiren-6-ylidene)-1-methylpiperidine chemical structure

4-(1a,10b-Dihydro-6H-dibenzo[3,4:6,7]cyclohepta[1,2-b]oxiren-6-ylidene)-1-methylpiperidine

CAS: 54191-04-7
Formula: C₂₁H₂₁NO
MW: 303.4 g/mol

VQ-035173

Reference Standard

4-(1H-1,2,4-Triazol-l-yl Methyl) Phenyl Hydrazine Dihydrochloride chemical structure

4-(1H-1,2,4-Triazol-l-yl Methyl) Phenyl Hydrazine Dihydrochloride

CAS: 212248-62-9
Formula: C₉H₁₂ClN₅
MW: 225.68 g/mol

VQ-027865

Reference Standard

4-(2-((4-(4-Methoxyphenyl)butan-2-yl)amino)ethyl)benzene-1,2-diol Hydrochloride chemical structure

4-(2-((4-(4-Methoxyphenyl)butan-2-yl)amino)ethyl)benzene-1,2-diol Hydrochloride

CAS: 82473-36-7
Formula: C₁₉H₂₆ClNO₃
MW: 351.9 g/mol

VQ-030243

Reference Standard

4-(2-((4-Acetamidophenyl)amino)pyrimidin-4-yl)-N-(cyanomethyl)benzamide chemical structure

4-(2-((4-Acetamidophenyl)amino)pyrimidin-4-yl)-N-(cyanomethyl)benzamide

CAS: 1841094-22-1
Formula: C₂₁H₁₈N₆O₂
MW: 386.4 g/mol

VQ-031975

Reference Standard

4-(2-((4-Morpholinophenyl)amino)pyrimidin-4-yl)benzoic Acid chemical structure

4-(2-((4-Morpholinophenyl)amino)pyrimidin-4-yl)benzoic Acid

CAS: 945749-71-3
Formula: C₂₁H₂₀N₄O₃
MW: 376.4 g/mol

VQ-026757

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