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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-(2,3-Dichlorophenyl)-2,6-dimethyl-3-pyridinecarboxylic acid methyl ester chemical structure

4-(2,3-Dichlorophenyl)-2,6-dimethyl-3-pyridinecarboxylic acid methyl ester

CAS: 105383-68-4
Formula: C₁₅H₁₃Cl₂NO₂
MW: 310.2 g/mol

VQ-022214

Reference Standard

4-(2,3-Dichlorophenyl)-5-(methoxycarbonyl)-2,6-dimethylnicotinic acid chemical structure

4-(2,3-Dichlorophenyl)-5-(methoxycarbonyl)-2,6-dimethylnicotinic acid

CAS: 91854-02-3
Formula: C₁₆H₁₃Cl₂NO₄
MW: 354.2 g/mol

VQ-025010

Reference Standard

4-(2,3-Dichlorophenyl)-N,N-dimethylpiperazine-1-carboxamide chemical structure

4-(2,3-Dichlorophenyl)-N,N-dimethylpiperazine-1-carboxamide

CAS: 2327471-74-7
Formula: C₁₃H₁₇Cl₂N₃O
MW: 302.2 g/mol

VQ-022021

Reference Standard

4-(2,4-Diaminophenyl)-3-morpholinone chemical structure

4-(2,4-Diaminophenyl)-3-morpholinone

CAS: 482308-13-4
Formula: C₁₀H₁₃N₃O₂
MW: 207.23 g/mol

VQ-027853

Reference Standard

4-(2,4-Dichloro-5-methoxyphenylamino)-6,7-dimethoxyquinoline-3-carbonitrile chemical structure

4-(2,4-Dichloro-5-methoxyphenylamino)-6,7-dimethoxyquinoline-3-carbonitrile

CAS: 380843-12-9
Formula: C₁₉H₁₅Cl₂N₃O₃
MW: 404.2 g/mol

VQ-024626

Reference Standard

4-(2,4-Dichlorophenyl)-3,4-dihydronaphthalen-1(2H)-one chemical structure

4-(2,4-Dichlorophenyl)-3,4-dihydronaphthalen-1(2H)-one

CAS: 127293-50-9
Formula: C₁₆H₁₂Cl₂O
MW: 291.2 g/mol

VQ-042146

Reference Standard

4-(3-((3,4-Dimethoxyphenethyl)amino)butyl)phenol chemical structure

4-(3-((3,4-Dimethoxyphenethyl)amino)butyl)phenol

CAS: 140165-60-2
Formula: C₂₀H₂₇NO₃
MW: 329.4 g/mol

VQ-045163

Reference Standard

4-(3-((4-Chloro-7-methoxyquinazolin-6-yl)oxy)propyl)morpholine chemical structure

4-(3-((4-Chloro-7-methoxyquinazolin-6-yl)oxy)propyl)morpholine

CAS: 199327-59-8
Formula: C₁₆H₂₀ClN₃O₃
MW: 337.8 g/mol

VQ-037492

Reference Standard

4-(3-(1-(4-Cyano-3-(trifluoromethyl)phenyl)-3-methyl-4-oxo-2-thioxo-1,2,3,4-tetrahydroquinazolin-7-yl)-4,4-dimethyl-5-oxo-2-thioxoimidazolidin-1-yl)-2-(trifluoromethyl)benzonitrile chemical structure

4-(3-(1-(4-Cyano-3-(trifluoromethyl)phenyl)-3-methyl-4-oxo-2-thioxo-1,2,3,4-tetrahydroquinazolin-7-yl)-4,4-dimethyl-5-oxo-2-thioxoimidazolidin-1-yl)-2-(trifluoromethyl)benzonitrile

CAS: 2810090-73-2
Formula: C₃₀H₁₈F₆N₆O₂S₂
MW: 672.6 g/mol

VQ-021219

Reference Standard

4-(3-(2,5-Dichloro-4,6-dimethylpyridin-3-yl)-1,2,4-oxadiazol-5-yl)-2-methoxy-6-nitrophenol chemical structure

4-(3-(2,5-Dichloro-4,6-dimethylpyridin-3-yl)-1,2,4-oxadiazol-5-yl)-2-methoxy-6-nitrophenol

CAS: 1391712-50-7
Formula: C₁₆H₁₂Cl₂N₄O₅
MW: 411.2 g/mol

VQ-023339

Reference Standard

4-(3-(3,5-Dichlorophenyl)-4,4,4-trifluorobut-2-enoyl)-2-methylbenzoic acid chemical structure

4-(3-(3,5-Dichlorophenyl)-4,4,4-trifluorobut-2-enoyl)-2-methylbenzoic acid

CAS: 1095275-26-5
Formula: C₁₈H₁₁Cl₂F₃O₃
MW: 403.2 g/mol

VQ-048436

Reference Standard

4-(3-(4-(Cyclopropanecarbonyl)piperazine-1-carbonyl)-4-fluorobenzoyl)phthalazin-1(2H)-one chemical structure

4-(3-(4-(Cyclopropanecarbonyl)piperazine-1-carbonyl)-4-fluorobenzoyl)phthalazin-1(2H)-one

CAS: 1460272-52-9
Formula: C₂₄H₂₁FN₄O₄
MW: 448.4 g/mol

VQ-032232

Reference Standard

4-(3-(4-(tert-Butyl)phenyl)-2-methylpropyl)-2,6-dimethylmorpholine chemical structure

4-(3-(4-(tert-Butyl)phenyl)-2-methylpropyl)-2,6-dimethylmorpholine

CAS: 67306-03-0
Formula: C₂₀H₃₃NO
MW: 303.5 g/mol

VQ-035710

Reference Standard

4-(3-(4-Cyano-3-(trifluoromethyl)phenyl)-5,5-dimethyl-2,4-dioxoimidazolidin-1-yl)-2-fluorobenzamide chemical structure

4-(3-(4-Cyano-3-(trifluoromethyl)phenyl)-5,5-dimethyl-2,4-dioxoimidazolidin-1-yl)-2-fluorobenzamide

CAS: 1242137-17-2
Formula: C₂₀H₁₄F₄N₄O₃
MW: 434.3 g/mol

VQ-022543

Reference Standard

4-(3-(4-Cyano-3-(trifluoromethyl)phenyl)thioureido)-2-fluoro-N-methylbenzamide chemical structure

4-(3-(4-Cyano-3-(trifluoromethyl)phenyl)thioureido)-2-fluoro-N-methylbenzamide

CAS: 1798807-39-2
Formula: C₁₇H₁₂F₄N₄OS
MW: 396.4 g/mol

VQ-025549

Reference Standard

4-(3-(Dimethylamino)-1-(pyridin-2-yl)propyl)-N,N-dimethylaniline chemical structure

4-(3-(Dimethylamino)-1-(pyridin-2-yl)propyl)-N,N-dimethylaniline

CAS: 694490-86-3
Formula: C₁₈H₂₅N₃
MW: 283.4 g/mol

VQ-027456

Reference Standard

4-(3-Aminophenyl)-2-methyl-3-butyn-2-ol chemical structure

4-(3-Aminophenyl)-2-methyl-3-butyn-2-ol

CAS: 69088-96-6
Formula: C₁₁H₁₃NO
MW: 175.23 g/mol

VQ-037054

Reference Standard

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

4-(3-Aminophenyl)morpholin-3-one

CAS: 1082495-22-4
Formula: C₁₀H₁₂N₂O₂
MW: 192.21 g/mol

VQ-027848

Reference Standard

4-(3-Bromopropyl)-3,5-dimethyl-1H-pyrazole chemical structure

4-(3-Bromopropyl)-3,5-dimethyl-1H-pyrazole

CAS: 2167368-32-1
Formula: C₈H₁₃BrN₂
MW: 217.11 g/mol

VQ-040591

Reference Standard

4-(3-Bromopropyl)morpholine Hydrochloride chemical structure

4-(3-Bromopropyl)morpholine Hydrochloride

CAS: 134187-43-2
Formula: C₇H₁₅BrClNO
MW: 244.56 g/mol

VQ-044578

Reference Standard

4-(3-Carbamimidoylguanidino)benzoic acid chemical structure

4-(3-Carbamimidoylguanidino)benzoic acid

CAS: 22817-15-8
Formula: C₉H₁₁N₅O₂
MW: 221.22 g/mol

VQ-038346

Reference Standard

4-(3-Chlorophenyl)piperidine hydrochloride chemical structure

4-(3-Chlorophenyl)piperidine hydrochloride

CAS: 99329-70-1
Formula: C₁₁H₁₅Cl₂N
MW: 232.15 g/mol

VQ-044629

Reference Standard

4-(3-Chloropropyl)morpholine chemical structure

4-(3-Chloropropyl)morpholine

CAS: 7357-67-7
Formula: C₇H₁₄ClNO
MW: 163.64 g/mol

VQ-032804

Reference Standard

4-(3-Chlorothiophen-2-yl)thiazol-2-amine chemical structure

4-(3-Chlorothiophen-2-yl)thiazol-2-amine

CAS: 339114-12-4
Formula: C₇H₅ClN₂S₂
MW: 216.7 g/mol

VQ-035868

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