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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

1-(2-((4,6-Dichloro-2-methylpyrimidin-5-yl)amino)-4,5-dihydro-1H-imidazol-1-yl)ethan-1-one chemical structure

1-(2-((4,6-Dichloro-2-methylpyrimidin-5-yl)amino)-4,5-dihydro-1H-imidazol-1-yl)ethan-1-one

CAS: 75438-54-9
Formula: C₁₀H₁₁Cl₂N₅O
MW: 288.13 g/mol

VQ-038522

Reference Standard

1-(2-((5-Bromoquinoxalin-6-yl)amino)-4,5-dihydro-1H-imidazol-1-yl)ethan-1-one chemical structure

1-(2-((5-Bromoquinoxalin-6-yl)amino)-4,5-dihydro-1H-imidazol-1-yl)ethan-1-one

CAS: 1158184-23-6
Formula: C₁₃H₁₂BrN₅O
MW: 334.17 g/mol

VQ-029505

Reference Standard

1-(2-((5-Chloro-2,4-dimethylphenyl)thio)phenyl)piperazine chemical structure

1-(2-((5-Chloro-2,4-dimethylphenyl)thio)phenyl)piperazine

CAS: 1240670-87-4
Formula: C₁₈H₂₁ClN₂S
MW: 332.9 g/mol

VQ-034697

Reference Standard

1-(2-(4-(Chloromethyl)phenoxy)ethyl)azepane hydrochloride chemical structure

1-(2-(4-(Chloromethyl)phenoxy)ethyl)azepane hydrochloride

CAS: 223251-25-0
Formula: C₁₅H₂₃Cl₂NO
MW: 304.3 g/mol

VQ-020897

Reference Standard

1-(2-(4-Formyl-N-methylbenzamido)ethyl)piperidin-4-yl [1,1'-biphenyl]-2-ylcarbamate chemical structure

1-(2-(4-Formyl-N-methylbenzamido)ethyl)piperidin-4-yl [1,1'-biphenyl]-2-ylcarbamate

CAS: 864760-28-1
Formula: C₂₉H₃₁N₃O₄
MW: 485.6 g/mol

VQ-041890

Reference Standard

1-(2-(Benzylthio)-5-chlorothiophen-3-yl)ethanone chemical structure

1-(2-(Benzylthio)-5-chlorothiophen-3-yl)ethanone

CAS: 160982-09-2
Formula: C₁₃H₁₁ClOS₂
MW: 282.8 g/mol

VQ-036025

Reference Standard

1-(2-(Ethylsulfinyl)ethyl)-2-methyl-5-nitro-1H-imidazole chemical structure

1-(2-(Ethylsulfinyl)ethyl)-2-methyl-5-nitro-1H-imidazole

CAS: 2376335-05-4
Formula: C₈H₁₃N₃O₃S
MW: 231.27 g/mol

VQ-034283

Reference Standard

1-(2-(Ethylthio)ethyl)-2-methyl-4-nitro-1H-imidazole chemical structure

1-(2-(Ethylthio)ethyl)-2-methyl-4-nitro-1H-imidazole

CAS: 13230-19-8
Formula: C₈H₁₃N₃O₂S
MW: 215.28 g/mol

VQ-035182

Reference Standard

1-(2-(m-Tolylthio)phenyl)piperazine chemical structure

1-(2-(m-Tolylthio)phenyl)piperazine

CAS: 1293489-69-6
Formula: C₁₇H₂₀N₂S
MW: 284.4 g/mol

VQ-042945

Reference Standard

1-(2-(o-Tolylthio)phenyl)piperazine chemical structure

1-(2-(o-Tolylthio)phenyl)piperazine

CAS: 1293489-71-0
Formula: C₁₇H₂₀N₂S
MW: 284.4 g/mol

VQ-034691

Reference Standard

1-(2-(p-Tolylthio)phenyl)piperazine chemical structure

1-(2-(p-Tolylthio)phenyl)piperazine

CAS: 508233-82-7
Formula: C₁₇H₂₀N₂S
MW: 284.4 g/mol

VQ-028758

Reference Standard

1-(2-Aminophenyl)-3-morpholino-5,6-dihydropyridin-2(1H)-one chemical structure

1-(2-Aminophenyl)-3-morpholino-5,6-dihydropyridin-2(1H)-one

CAS: 2444918-46-9
Formula: C₁₅H₁₉N₃O₂
MW: 273.33 g/mol

VQ-035761

Reference Standard

1-(2-Bromo-1-methyl-vinyl)-2,4-difluoro-benzene chemical structure

1-(2-Bromo-1-methyl-vinyl)-2,4-difluoro-benzene

CAS: 159276-59-2
Formula: C₉H₇BrF₂
MW: 233.05 g/mol

VQ-041565

Reference Standard

1-(2-Bromo-6-chlorophenyl)indolin-2-one chemical structure

1-(2-Bromo-6-chlorophenyl)indolin-2-one

CAS: 1219112-85-2
Formula: C₁₄H₉BrClNO
MW: 322.58 g/mol

VQ-048009

Reference Standard

1-(2-Bromoethyl)-2-(2-nitrovinyl)benzene chemical structure

1-(2-Bromoethyl)-2-(2-nitrovinyl)benzene

CAS: 120427-94-3
Formula: C₁₀H₁₀BrNO₂
MW: 256.1 g/mol

VQ-041998

Reference Standard

1-(2-Bromophenyl)piperazine chemical structure

1-(2-Bromophenyl)piperazine

CAS: 1011-13-8
Formula: C₁₀H₁₃BrN₂
MW: 241.13 g/mol

VQ-028755

Reference Standard

1-(2-Chloroethoxy)-2-methoxy benzene chemical structure

1-(2-Chloroethoxy)-2-methoxy benzene

CAS: 53815-60-4
Formula: C₉H₁₁ClO₂
MW: 186.63 g/mol

VQ-029672

Reference Standard

1-(2-Chlorophenyl)-2-(1H-tetrazol-1-yl)ethan-1-one chemical structure

1-(2-Chlorophenyl)-2-(1H-tetrazol-1-yl)ethan-1-one

CAS: 1259059-68-1
Formula: C₉H₇ClN₄O
MW: 222.63 g/mol

VQ-042737

Reference Standard

1-(2-Chlorophenyl)-2-(1H-tetrazol-1-yl)ethyl carbamate chemical structure

1-(2-Chlorophenyl)-2-(1H-tetrazol-1-yl)ethyl carbamate

CAS: 913088-45-6
Formula: C₁₀H₁₀ClN₅O₂
MW: 267.67 g/mol

VQ-036219

Reference Standard

1-(2-Chlorophenyl)-2-(2H-tetrazol-2-yl)ethan-1-one chemical structure

1-(2-Chlorophenyl)-2-(2H-tetrazol-2-yl)ethan-1-one

CAS: 1259059-71-6
Formula: C₉H₇ClN₄O
MW: 222.63 g/mol

VQ-024900

Reference Standard

1-(2-Chlorophenyl)piperazine chemical structure

1-(2-Chlorophenyl)piperazine

CAS: 39512-50-0
Formula: C₁₀H₁₃ClN₂
MW: 196.67 g/mol

VQ-027521

Reference Standard

1-(2-Chlorophenyl)Piperazine Hydrochloride chemical structure

1-(2-Chlorophenyl)Piperazine Hydrochloride

CAS: 41202-32-8
Formula: C₁₀H₁₄Cl₂N₂
MW: 233.13 g/mol

VQ-041513

Reference Standard

1-(2-Chlorophenyl)propan-1-one chemical structure

1-(2-Chlorophenyl)propan-1-one

CAS: 6323-18-8
Formula: C₉H₉ClO
MW: 168.62 g/mol

VQ-029549

Reference Standard

1-(2-Deoxy-β-D-erythro-pentopyranosyl)-3-guanyl-urea chemical structure

1-(2-Deoxy-β-D-erythro-pentopyranosyl)-3-guanyl-urea

CAS: 570410-70-7
Formula: C₇H₁₄N₄O₄
MW: 218.21 g/mol

VQ-025220

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