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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-Bromomethylphenyl)benzonitrile chemical structure

4-(4-Bromomethylphenyl)benzonitrile

CAS: 50670-51-4
Formula: C₁₄H₁₀BrN
MW: 272.14 g/mol

VQ-026215

Reference Standard

4-(4-Bromophenyl)-1,2,3,6-tetrahydropyridine chemical structure

4-(4-Bromophenyl)-1,2,3,6-tetrahydropyridine

CAS: 91347-99-8
Formula: C₁₁H₁₂BrN
MW: 238.12 g/mol

VQ-037573

Reference Standard

4-(4-Carbamoyl-2-methoxyphenyl)-5-ethoxy-2,8-dimethyl-1,4-dihydro-1,6-naphthyridine-3-carboxamide chemical structure

4-(4-Carbamoyl-2-methoxyphenyl)-5-ethoxy-2,8-dimethyl-1,4-dihydro-1,6-naphthyridine-3-carboxamide

CAS: 3046142-41-7
Formula: C₂₁H₂₄N₄O₄
MW: 396.4 g/mol

VQ-030742

Reference Standard

4-(4-Chlorophenyl)-1-(1H-imidazol-1-yl)-2-butanol mononitrate chemical structure

4-(4-Chlorophenyl)-1-(1H-imidazol-1-yl)-2-butanol mononitrate

CAS: 67085-12-5
Formula: C₁₃H₁₄Cl₂N₂
MW: 269.17 g/mol

VQ-021943

Reference Standard

4-(4-Chlorophenyl)-1-(1H-imidazol-1-yl)butan-2-ol chemical structure

4-(4-Chlorophenyl)-1-(1H-imidazol-1-yl)butan-2-ol

CAS: 67085-11-4
Formula: C₁₃H₁₅ClN₂O
MW: 250.72 g/mol

VQ-021033

Reference Standard

4-(4-Chlorophenyl)-1,2,3,6-tetrahydropyridine Monohydrochloride chemical structure

4-(4-Chlorophenyl)-1,2,3,6-tetrahydropyridine Monohydrochloride

CAS: 51304-61-1
Formula: C₁₁H₁₃Cl₂N
MW: 230.13 g/mol

VQ-037571

Reference Standard

4-(4-Chlorophenyl)-1H-2,3-benzoxazin-1-one chemical structure

4-(4-Chlorophenyl)-1H-2,3-benzoxazin-1-one

CAS: 2224-83-1
Formula: C₁₄H₈ClNO₂
MW: 257.67 g/mol

VQ-029328

Reference Standard

4-(4-Chlorophenyl)-2-(4-ethylpiperazin-1-yl)-5,6,7,8,9,10-hexahydrocycloocta[b]pyridine chemical structure

4-(4-Chlorophenyl)-2-(4-ethylpiperazin-1-yl)-5,6,7,8,9,10-hexahydrocycloocta[b]pyridine

CAS: 132810-87-8
Formula: C₂₃H₃₀ClN₃
MW: 384 g/mol

VQ-029467

Reference Standard

4-(4-Chlorophenyl)cyclohexane-1-carboxylic Acid chemical structure

4-(4-Chlorophenyl)cyclohexane-1-carboxylic Acid

CAS: 95233-37-7
Formula: C₁₃H₁₅ClO₂
MW: 238.71 g/mol

VQ-044232

Reference Standard

4-(4-Chlorophenyl)piperidine-2,6-dione chemical structure

4-(4-Chlorophenyl)piperidine-2,6-dione

CAS: 84803-46-3
Formula: C₁₁H₁₀ClNO₂
MW: 223.65 g/mol

VQ-021729

Reference Standard

4-(4-Chlorothiophen-2-yl)thiazol-2-amine chemical structure

4-(4-Chlorothiophen-2-yl)thiazol-2-amine

CAS: 570407-10-2
Formula: C₇H₅ClN₂S₂
MW: 216.7 g/mol

VQ-024445

Reference Standard

4-(4-Cyano-2-methoxyphenyl)-5-ethoxy-2,8-dimethyl-1,4-dihydro-1,6-naphthyridine-3-carboxylic Acid chemical structure

4-(4-Cyano-2-methoxyphenyl)-5-ethoxy-2,8-dimethyl-1,4-dihydro-1,6-naphthyridine-3-carboxylic Acid

CAS: 1050477-45-6
Formula: C₂₁H₂₁N₃O₄
MW: 379.4 g/mol

VQ-022647

Reference Standard

4-(4-Cyanobenzyl)-1,2,4-triazole chemical structure

4-(4-Cyanobenzyl)-1,2,4-triazole

CAS: 112809-27-5
Formula: C₁₀H₈N₄
MW: 184.2 g/mol

VQ-048844

Reference Standard

4-(4-Ethyl-2,6-diiodophenoxy)-2,6-diiodo-phenol chemical structure

4-(4-Ethyl-2,6-diiodophenoxy)-2,6-diiodo-phenol

CAS: 176258-89-2
Formula: C₁₄H₁₀I₄O₂
MW: 717.84 g/mol

VQ-043506

Reference Standard

4-(4-Ethyl-3-iodophenyl)-4-methyl-3-oxopentanoic Acid

4-(4-Ethyl-3-iodophenyl)-4-methyl-3-oxopentanoic Acid

CAS: 2234855-03-7
Formula: C₁₄H₁₇IO₃
MW: 360.19 g/mol

VQ-035651

Reference Standard

4-(4-Fluoro-2-methylphenyl)-5-nitropyridin-2(1H)-one chemical structure

4-(4-Fluoro-2-methylphenyl)-5-nitropyridin-2(1H)-one

CAS: 2642577-27-1
Formula: C₁₂H₉FN₂O₃
MW: 248.21 g/mol

VQ-030439

Reference Standard

4-(4-Fluorobenzoyl)-Butyric acid chemical structure

4-(4-Fluorobenzoyl)-Butyric acid

CAS: 149437-76-3
Formula: C₁₁H₁₁FO₃
MW: 210.2 g/mol

VQ-027202

Reference Standard

4-(4-Fluorophenyl)-5,6,7,8,9,10-hexahydrocycloocta[b]pyridin-2(1H)-one chemical structure

4-(4-Fluorophenyl)-5,6,7,8,9,10-hexahydrocycloocta[b]pyridin-2(1H)-one

CAS: 132812-72-7
Formula: C₁₇H₁₈FNO
MW: 271.33 g/mol

VQ-047604

Reference Standard

4-(4-Fluorophenyl)-6-(1-methylethyl)-2-[methyl(methylsulfonyl)amino]-5-pyrimidinecarboxylic acid chemical structure

4-(4-Fluorophenyl)-6-(1-methylethyl)-2-[methyl(methylsulfonyl)amino]-5-pyrimidinecarboxylic acid

CAS: 1263475-93-9
Formula: C₁₆H₁₈FN₃O₄S
MW: 367.4 g/mol

VQ-027906

Reference Standard

4-(4-Methoxybenzamido)butanoic Acid chemical structure

4-(4-Methoxybenzamido)butanoic Acid

CAS: 72432-14-5
Formula: C₁₂H₁₅NO₄
MW: 237.25 g/mol

VQ-024303

Reference Standard

4-(4-Methoxyphenyl)butyric acid chemical structure

4-(4-Methoxyphenyl)butyric acid

CAS: 4521-28-2
Formula: C₁₁H₁₄O₃
MW: 194.23 g/mol

VQ-024171

Reference Standard

4-(4-Methylphenyl)-4-oxobutyric Acid chemical structure

4-(4-Methylphenyl)-4-oxobutyric Acid

CAS: 4619-20-9
Formula: C₁₁H₁₂O₃
MW: 192.21 g/mol

VQ-034763

Reference Standard

4-(4-Methylpiperazinomethyl)-3-(trifluoromethyl)aniline chemical structure

4-(4-Methylpiperazinomethyl)-3-(trifluoromethyl)aniline

CAS: 694499-26-8
Formula: C₁₃H₁₈F₃N₃
MW: 273.3 g/mol

VQ-023514

Reference Standard

4-(4-Methylpiperazinomethyl)benzonitrile chemical structure

4-(4-Methylpiperazinomethyl)benzonitrile

CAS: 125743-63-7
Formula: C₁₃H₁₇N₃
MW: 215.29 g/mol

VQ-027177

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