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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

3beta-Hydroxy-delta5-cholenic acid chemical structure

3beta-Hydroxy-delta5-cholenic acid

CAS: 5255-17-4
Formula: C₂₄H₃₈O₃
MW: 374.6 g/mol

VQ-039586

Reference Standard

3H,6H-2a,5,6,8a-Tetraazaacenaphthylene, octahydro-5a,8b-dimethyl-, cis chemical structure

3H,6H-2a,5,6,8a-Tetraazaacenaphthylene, octahydro-5a,8b-dimethyl-, cis

CAS: 214195-92-3
Formula: C₁₀H₂₀N₄
MW: 196.29 g/mol

VQ-030927

Reference Standard

3N-Benzyl Biotin chemical structure

3N-Benzyl Biotin

CAS: 57229-92-2
Formula: C₁₇H₂₂N₂O₃S
MW: 334.4 g/mol

VQ-021837

Reference Standard

3R 5s 6 chloro 3 5 dihydroxyhexanoic acid chemical structure

3R 5s 6 chloro 3 5 dihydroxyhexanoic acid

CAS: 958358-67-3
Formula: C₆H₁₁ClO₄
MW: 182.6 g/mol

VQ-033667

Reference Standard

3β-17-Imino-androst-5-en-3-ol dimer chemical structure

3β-17-Imino-androst-5-en-3-ol dimer

CAS: 491873-45-1
Formula: C₃₈H₅₆N₂O₂
MW: 572.9 g/mol

VQ-024113

Reference Standard

3β,5-Dihydroxy-15β,16β-methylene-5β-androst-6-en-17-one chemical structure

3β,5-Dihydroxy-15β,16β-methylene-5β-androst-6-en-17-one

CAS: 82543-15-5
Formula: C₂₀H₂₈O₃
MW: 316.4 g/mol

VQ-043034

Reference Standard

4 1 2 Cyano 1 cyclopentylethyl 1h pyrazol 4 yl 7h pyrrolo 2 3 d pyrimidin 7 yl methyl pivalate chemical structure

4 1 2 Cyano 1 cyclopentylethyl 1h pyrazol 4 yl 7h pyrrolo 2 3 d pyrimidin 7 yl methyl pivalate

CAS: 1236033-05-8
Formula: C₂₃H₂₈N₆O₂
MW: 420.5 g/mol

VQ-042045

Reference Standard

4 2 Chlorophenyl piperidine hydrochloride chemical structure

4 2 Chlorophenyl piperidine hydrochloride

CAS: 82211-92-5
Formula: C₁₁H₁₅Cl₂N
MW: 232.15 g/mol

VQ-044628

Reference Standard

4 4 2 Isopropoxyethoxy methyl phenoxy methyl phenol chemical structure

4 4 2 Isopropoxyethoxy methyl phenoxy methyl phenol

CAS: 2417155-10-1
Formula: C₁₉H₂₄O₄
MW: 316.4 g/mol

VQ-047600

Reference Standard

4 4 Methylamino phenyl morpholin 3 one chemical structure

4 4 Methylamino phenyl morpholin 3 one

CAS: 1224684-98-3
Formula: C₁₁H₁₄N₂O₂
MW: 206.24 g/mol

VQ-033605

Reference Standard

4 Bromo 1 benzothiophene 2 carboxylic acid chemical structure

4 Bromo 1 benzothiophene 2 carboxylic acid

CAS: 5194-37-6
Formula: C₉H₅BrO₂S
MW: 257.11 g/mol

VQ-036017

Reference Standard

4 Bromo 1 chloro 2 4 methoxybenzyl benzene chemical structure

4 Bromo 1 chloro 2 4 methoxybenzyl benzene

CAS: 333361-51-6
Formula: C₁₄H₁₂BrClO
MW: 311.6 g/mol

VQ-048200

Reference Standard

4 Ethyl 5 methyl 2 2 nitrophenyl amino isophthalonitrile chemical structure

4 Ethyl 5 methyl 2 2 nitrophenyl amino isophthalonitrile

CAS: 2554975-45-8
Formula: C₁₇H₁₄N₄O₂
MW: 306.32 g/mol

VQ-038722

Reference Standard

4 Iodomethyl 5 methyl 1 3 dioxol 2 one chemical structure

4 Iodomethyl 5 methyl 1 3 dioxol 2 one

CAS: 80841-79-8
Formula: C₅H₅IO₃
MW: 240 g/mol

VQ-035895

Reference Standard

4 Nitrophenyl ethyl methyl carbamate chemical structure

4 Nitrophenyl ethyl methyl carbamate

CAS: 90870-20-5
Formula: C₁₀H₁₂N₂O₄
MW: 224.21 g/mol

VQ-041971

Reference Standard

4 Phenoxybenzohydrazide chemical structure

4 Phenoxybenzohydrazide

CAS: 143667-36-1
Formula: C₁₃H₁₂N₂O₂
MW: 228.25 g/mol

VQ-048602

Reference Standard

4`-[[2-Butyl-4-chloro-5-(chloromethyl)-1H-imidazol-1-yl]methyl](1,1`-biphenyl)-2-carbonitrile chemical structure

4`-[[2-Butyl-4-chloro-5-(chloromethyl)-1H-imidazol-1-yl]methyl](1,1`-biphenyl)-2-carbonitrile

CAS: 757149-84-1
Formula: C₂₂H₂₁Cl₂N₃
MW: 398.3 g/mol

VQ-038146

Reference Standard

4`-Fluoro-Biphenyl-2-ylamine chemical structure

4`-Fluoro-Biphenyl-2-ylamine

CAS: 321-63-1
Formula: C₁₂H₁₀FN
MW: 187.21 g/mol

VQ-040038

Reference Standard

4- Fluoro Safinamide chemical structure

4- Fluoro Safinamide

CAS: 202825-43-2
Formula: C₁₇H₁₉FN₂O₂
MW: 302.34 g/mol

VQ-023713

Reference Standard

4-(((2S,4R)-1-([1,1'-Biphenyl]-4-yl)-5-isopropoxy-4-methyl-5-oxopentan-2-yl)amino)-4-oxobutanoic acid chemical structure

4-(((2S,4R)-1-([1,1'-Biphenyl]-4-yl)-5-isopropoxy-4-methyl-5-oxopentan-2-yl)amino)-4-oxobutanoic acid

CAS: 2514965-95-6
Formula: C₂₅H₃₁NO₅
MW: 425.5 g/mol

VQ-027960

Reference Standard

4-(((5-((2-Oxo-5-vinylpyrrolidin-1-yl)methyl)furan-2-yl)methylene)amino)hex-5-enoic Acid

4-(((5-((2-Oxo-5-vinylpyrrolidin-1-yl)methyl)furan-2-yl)methylene)amino)hex-5-enoic Acid

CAS: 158878-96-7
Formula: C₁₈H₂₂N₂O₄
MW: 330.38 g/mol

VQ-042876

Reference Standard

4-(((Benzyloxy)carbonyl)amino)benzoic acid chemical structure

4-(((Benzyloxy)carbonyl)amino)benzoic acid

CAS: 5330-71-2
Formula: C₁₅H₁₃NO₄
MW: 271.27 g/mol

VQ-038448

Reference Standard

4-((1-((6-Cyano-5-(trifluoromethyl)pyridin-3-yl)carbamoyl)cyclobutyl)amino)-2-fluoro-N-methylbenzamide chemical structure

4-((1-((6-Cyano-5-(trifluoromethyl)pyridin-3-yl)carbamoyl)cyclobutyl)amino)-2-fluoro-N-methylbenzamide

CAS: 1950587-20-8
Formula: C₂₀H₁₇F₄N₅O₂
MW: 435.4 g/mol

VQ-024309

Reference Standard

4-((1-Cyanocyclobutyl)amino)-2-fluoro-N-methylbenzamide chemical structure

4-((1-Cyanocyclobutyl)amino)-2-fluoro-N-methylbenzamide

CAS: 915087-26-2
Formula: C₁₃H₁₄FN₃O
MW: 247.27 g/mol

VQ-029171

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