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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-[(1-Oxoheptyl)amino]benzoic acid ethyl ester chemical structure

4-[(1-Oxoheptyl)amino]benzoic acid ethyl ester

CAS: 86927-24-4
Formula: C₁₆H₂₃NO₃
MW: 277.36 g/mol

VQ-043970

Reference Standard

4-[(2-Butyl-5-formyl-1H-imidazol-1-yl)methyl]benzoic Acid chemical structure

4-[(2-Butyl-5-formyl-1H-imidazol-1-yl)methyl]benzoic Acid

CAS: 152146-59-3
Formula: C₁₆H₁₈N₂O₃
MW: 286.33 g/mol

VQ-022547

Reference Standard

4-[(2-Ethoxybenzoyl)amino]-1-methyl-5-propyl-1H-pyrazole-3-carboxamide chemical structure

4-[(2-Ethoxybenzoyl)amino]-1-methyl-5-propyl-1H-pyrazole-3-carboxamide

CAS: 501120-38-3
Formula: C₁₇H₂₂N₄O₃
MW: 330.4 g/mol

VQ-043166

Reference Standard

4-[(2,4-Dimethylphenyl)sulfanyl]aniline hydrochloride chemical structure

4-[(2,4-Dimethylphenyl)sulfanyl]aniline hydrochloride

CAS: 1049755-55-6
Formula: C₁₄H₁₆ClNS
MW: 265.8 g/mol

VQ-044809

Reference Standard

4-[(2,6-Dimethyl-3-nitro-4-pyridinyl)amino]benzeneethanol chemical structure

4-[(2,6-Dimethyl-3-nitro-4-pyridinyl)amino]benzeneethanol

CAS: 415908-90-6
Formula: C₁₅H₁₇N₃O₃
MW: 287.31 g/mol

VQ-044768

Reference Standard

4-[(4-Amino-2-ethoxy-5-nitrobenzoyl)amino]-1-piperidinecarboxylic Acid Ethyl Ester chemical structure

4-[(4-Amino-2-ethoxy-5-nitrobenzoyl)amino]-1-piperidinecarboxylic Acid Ethyl Ester

CAS: 952309-99-8
Formula: C₁₇H₂₄N₄O₆
MW: 380.4 g/mol

VQ-043473

Reference Standard

4-[(4-Chloro-2-pyrimidinyl)amino]benzonitrile chemical structure

4-[(4-Chloro-2-pyrimidinyl)amino]benzonitrile

CAS: 244768-32-9
Formula: C₁₁H₇ClN₄
MW: 230.65 g/mol

VQ-021331

Reference Standard

4-[(4-Methylpiperazin-1-yl)methyl]benzoic acid dihydrochloride chemical structure

4-[(4-Methylpiperazin-1-yl)methyl]benzoic acid dihydrochloride

CAS: 106261-49-8
Formula: C₁₃H₂₀Cl₂N₂O₂
MW: 307.21 g/mol

VQ-022834

Reference Standard

4-[(4-Oxo-1, 4-Dihydropyrimidin-2-yl)amino]-Benzonitrile chemical structure

4-[(4-Oxo-1, 4-Dihydropyrimidin-2-yl)amino]-Benzonitrile

CAS: 189956-45-4
Formula: C₁₁H₈N₄O
MW: 212.21 g/mol

VQ-027817

Reference Standard

4-[(5,6,7,8-Tetrahydro-3,5,5,8,8-pentamethyl-2-naphthalenyl)carbonyl]benzoic Acid chemical structure

4-[(5,6,7,8-Tetrahydro-3,5,5,8,8-pentamethyl-2-naphthalenyl)carbonyl]benzoic Acid

CAS: 153559-46-7
Formula: C₂₃H₂₆O₃
MW: 350.4 g/mol

VQ-028815

Reference Standard

4-[(7-Chloro-4-quinolinyl)imino]-2-[(diethylamino)methyl]-2,5-cyclohexadien-1-one chemical structure

4-[(7-Chloro-4-quinolinyl)imino]-2-[(diethylamino)methyl]-2,5-cyclohexadien-1-one

CAS: 112430-12-3
Formula: C₂₀H₂₀ClN₃O
MW: 353.8 g/mol

VQ-035350

Reference Standard

4-[(Aminocarbonyl)amino]-D-phenylalanine chemical structure

4-[(Aminocarbonyl)amino]-D-phenylalanine

CAS: 1808153-79-8
Formula: C₁₀H₁₃N₃O₃
MW: 223.23 g/mol

VQ-036610

Reference Standard

4-[[(2-Amino-3,5-dibromophenyl)methylene]amino]cyclohexanol chemical structure

4-[[(2-Amino-3,5-dibromophenyl)methylene]amino]cyclohexanol

CAS: 1445719-53-8
Formula: C₁₃H₁₆Br₂N₂O
MW: 376.09 g/mol

VQ-035674

Reference Standard

4-[[(Hexahydro-2,6-dioxo-4-pyrimidinyl)carbonyl]amino]-L-phenylalanine chemical structure

4-[[(Hexahydro-2,6-dioxo-4-pyrimidinyl)carbonyl]amino]-L-phenylalanine

CAS: 1808153-80-1
Formula: C₁₄H₁₆N₄O₅
MW: 320.3 g/mol

VQ-036609

Reference Standard

4-[[2-(Octyloxy)benzoyl]amino]benzoic Acid 2-(Diethylamino)ethyl Ester chemical structure

4-[[2-(Octyloxy)benzoyl]amino]benzoic Acid 2-(Diethylamino)ethyl Ester

CAS: 26090-29-9
Formula: C₂₈H₄₀N₂O₄
MW: 468.6 g/mol

VQ-041250

Reference Standard

4-[[2-Ethoxy-5-[(4-methyl-1-piperazinyl)- sulfonyl]benzoyl]amino]-1-methyl-3-propyl- 1H-pyrazole-5-carboxamide chemical structure

4-[[2-Ethoxy-5-[(4-methyl-1-piperazinyl)- sulfonyl]benzoyl]amino]-1-methyl-3-propyl- 1H-pyrazole-5-carboxamide

CAS: 200575-15-1
Formula: C₂₂H₃₂N₆O₅S
MW: 492.6 g/mol

VQ-028022

Reference Standard

4-[[3-(4-Methylphenyl)-3-oxo-1-(trifluoromethyl)propylidene]amino]benzenesulfonamide chemical structure

4-[[3-(4-Methylphenyl)-3-oxo-1-(trifluoromethyl)propylidene]amino]benzenesulfonamide

CAS: 1061214-09-2
Formula: C₁₇H₁₅F₃N₂O₃S
MW: 384.4 g/mol

VQ-021121

Reference Standard

4-[[3-[2-(3-Chlorophenyl)ethyl]-2-pyridinyl]carbonyl]-1-piperidinecarboxylic Acid Ethyl Ester chemical structure

4-[[3-[2-(3-Chlorophenyl)ethyl]-2-pyridinyl]carbonyl]-1-piperidinecarboxylic Acid Ethyl Ester

CAS: 107256-32-6
Formula: C₂₂H₂₅ClN₂O₃
MW: 400.9 g/mol

VQ-031634

Reference Standard

4-[[5-[[(Cyclopentyloxy)carbonyl]amino]-1-methyl-1H-indol-3-yl]methyl]-3-methoxy-benzoic acid methyl ester chemical structure

4-[[5-[[(Cyclopentyloxy)carbonyl]amino]-1-methyl-1H-indol-3-yl]methyl]-3-methoxy-benzoic acid methyl ester

CAS: 107754-19-8
Formula: C₂₅H₂₈N₂O₅
MW: 436.5 g/mol

VQ-028769

Reference Standard

4-[[5-[[(Cyclopentyloxy)carbonyl]amino]-1-methyl-1H-indol-3-yl]methyl]-3-methoxybenzoic acid chemical structure

4-[[5-[[(Cyclopentyloxy)carbonyl]amino]-1-methyl-1H-indol-3-yl]methyl]-3-methoxybenzoic acid

CAS: 107754-20-1
Formula: C₂₄H₂₆N₂O₅
MW: 422.5 g/mol

VQ-034719

Reference Standard

4-[2-(1-Azepanyl)ethoxy]benzaldehyde chemical structure

4-[2-(1-Azepanyl)ethoxy]benzaldehyde

CAS: 223251-09-0
Formula: C₁₅H₂₁NO₂
MW: 247.33 g/mol

VQ-020898

Reference Standard

4-[2-(2-Amino-4,5,6,7-tetrahydro-4,6-dioxo-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoic Acid chemical structure

4-[2-(2-Amino-4,5,6,7-tetrahydro-4,6-dioxo-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoic Acid

CAS: 193265-47-3
Formula: C₁₅H₁₄N₄O₄
MW: 314.3 g/mol

VQ-041374

Reference Standard

4-[2-(2-Amino-4,7-dihydro-4-oxo-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoic Acid Methyl Ester chemical structure

4-[2-(2-Amino-4,7-dihydro-4-oxo-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoic Acid Methyl Ester

CAS: 155405-80-4
Formula: C₁₆H₁₆N₄O₃
MW: 312.32 g/mol

VQ-027415

Reference Standard

4-[2-(4-Nitro-1H-imidazol-1-yl)ethyl]morpholine chemical structure

4-[2-(4-Nitro-1H-imidazol-1-yl)ethyl]morpholine

CAS: 6497-78-5
Formula: C₉H₁₄N₄O₃
MW: 226.23 g/mol

VQ-032169

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