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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-Piperidinopiperidine-1-carbonyl Chloride chemical structure

4-Piperidinopiperidine-1-carbonyl Chloride

CAS: 103816-19-9
Formula: C₁₁H₁₉ClN₂O
MW: 230.73 g/mol

VQ-043718

Reference Standard

4-Piperidyl n-(2-biphenyl)carbamate chemical structure

4-Piperidyl n-(2-biphenyl)carbamate

CAS: 171722-92-2
Formula: C₁₈H₂₀N₂O₂
MW: 296.4 g/mol

VQ-033515

Reference Standard

4-Pregnen-17alpha,20alpha-diol-3-one chemical structure

4-Pregnen-17alpha,20alpha-diol-3-one

CAS: 652-69-7
Formula: C₂₁H₃₂O₃
MW: 332.5 g/mol

VQ-041695

Reference Standard

4-Propyldihydrofuran-2(3H)-one chemical structure

4-Propyldihydrofuran-2(3H)-one

CAS: 72397-60-5
Formula: C₇H₁₂O₂
MW: 128.17 g/mol

VQ-027483

Reference Standard

4-Pyridylacetic acid hydrochloride chemical structure

4-Pyridylacetic acid hydrochloride

CAS: 6622-91-9
Formula: C₇H₈ClNO₂
MW: 173.6 g/mol

VQ-041929

Reference Standard

4-Tert-Butylbenzenesulfonic acid chemical structure

4-Tert-Butylbenzenesulfonic acid

CAS: 1133-17-1
Formula: C₁₀H₁₄O₃S
MW: 214.28 g/mol

VQ-029479

Reference Standard

4-tert-Butylbenzyl Chloride chemical structure

4-tert-Butylbenzyl Chloride

CAS: 19692-45-6
Formula: C₁₁H₁₅Cl
MW: 182.69 g/mol

VQ-024710

Reference Standard

4-Thiazolidinecarboxylic acid, 5,5-dimethyl-2-[[[(5-methyl-3-phenyl-4-isoxazolyl)carbonyl]amino]methyl]-, (4S) chemical structure

4-Thiazolidinecarboxylic acid, 5,5-dimethyl-2-[[[(5-methyl-3-phenyl-4-isoxazolyl)carbonyl]amino]methyl]-, (4S)

CAS: 1642559-63-4
Formula: C₁₈H₂₁N₃O₄S
MW: 375.4 g/mol

VQ-027321

Reference Standard

4-Tolyl Disulfide chemical structure

4-Tolyl Disulfide

CAS: 103-19-5
Formula: C₁₄H₁₄S₂
MW: 246.4 g/mol

VQ-028756

Reference Standard

4,4`-Diaminobibenzyl chemical structure

4,4`-Diaminobibenzyl

CAS: 621-95-4
Formula: C₁₄H₁₆N₂
MW: 212.29 g/mol

VQ-039709

Reference Standard

4,4-Dibromo-2,4-dihydro-5-methyl-3H-pyrazol-3-one chemical structure

4,4-Dibromo-2,4-dihydro-5-methyl-3H-pyrazol-3-one

CAS: 33549-66-5
Formula: C₄H₄Br₂N₂O
MW: 255.9 g/mol

VQ-041090

Reference Standard

4,4-Dichlorobutanoic acid chemical structure

4,4-Dichlorobutanoic acid

CAS: 151675-58-0
Formula: C₄H₆Cl₂O₂
MW: 156.99 g/mol

VQ-039623

Reference Standard

4,4-Dichlorodiphenyl Sulfone chemical structure

4,4-Dichlorodiphenyl Sulfone

CAS: 80-07-9
Formula: C₁₂H₈Cl₂O₂S
MW: 287.2 g/mol

VQ-025186

Reference Standard

4,4-Difluoro-1-(3-fluoro-4-methoxyphenyl)butane-1,3-dione chemical structure

4,4-Difluoro-1-(3-fluoro-4-methoxyphenyl)butane-1,3-dione

CAS: 170570-77-1
Formula: C₁₁H₉F₃O₃
MW: 246.18 g/mol

VQ-036617

Reference Standard

4,4-Difluorocyclohexanecarboxylic acid chemical structure

4,4-Difluorocyclohexanecarboxylic acid

CAS: 122665-97-8
Formula: C₇H₁₀F₂O₂
MW: 164.15 g/mol

VQ-031724

Reference Standard

4,4-Dimethyl-2-pentynal chemical structure

4,4-Dimethyl-2-pentynal

CAS: 2579-21-7
Formula: C₇H₁₀O
MW: 110.15 g/mol

VQ-032608

Reference Standard

4,4-Dimethyldihydrofuran-2,3-dione chemical structure

4,4-Dimethyldihydrofuran-2,3-dione

CAS: 13031-04-4
Formula: C₆H₈O₃
MW: 128.13 g/mol

VQ-030155

Reference Standard

4,4-Thiobis(2-(tert-butyl)-5-methylphenol) chemical structure

4,4-Thiobis(2-(tert-butyl)-5-methylphenol)

CAS: 96-69-5
Formula: C₂₂H₃₀O₂S
MW: 358.5 g/mol

VQ-032506

Reference Standard

4,4,4-Trifluoro-1-[2-(methyl)phenyl]-butane-1,3-dione chemical structure

4,4,4-Trifluoro-1-[2-(methyl)phenyl]-butane-1,3-dione

CAS: 163266-02-2
Formula: C₁₁H₉F₃O₂
MW: 230.18 g/mol

VQ-029722

Reference Standard

4,4,4-Trifluoro-1-[3-(methyl)phenyl]-butane-1,3-dione chemical structure

4,4,4-Trifluoro-1-[3-(methyl)phenyl]-butane-1,3-dione

CAS: 53764-99-1
Formula: C₁₁H₉F₃O₂
MW: 230.18 g/mol

VQ-024896

Reference Standard

4,4,5,5,5-Pentafluoropentanol chemical structure

4,4,5,5,5-Pentafluoropentanol

CAS: 148043-73-6
Formula: C₅H₇F₅O
MW: 178.1 g/mol

VQ-025934

Reference Standard

4,4,5,5,5-Pentafluoropentyl Methanesulfonate chemical structure

4,4,5,5,5-Pentafluoropentyl Methanesulfonate

CAS: 252947-01-6
Formula: C₆H₉F₅O₃S
MW: 256.19 g/mol

VQ-025932

Reference Standard

4,4'-((2S,3S,5S,8R,9S,10S,13S,14S,16S,17R)-3,17-Dihydroxy-10,13-dimethylhexadecahydro-1H-cyclopenta[a]phenanthrene-2,16-diyl)bis(1,1-dimethylpiperazin-1-ium) Bromide chemical structure

4,4'-((2S,3S,5S,8R,9S,10S,13S,14S,16S,17R)-3,17-Dihydroxy-10,13-dimethylhexadecahydro-1H-cyclopenta[a]phenanthrene-2,16-diyl)bis(1,1-dimethylpiperazin-1-ium) Bromide

CAS: 74133-45-2
Formula: C₃₁H₅₈Br₂N₄O₂
MW: 678.6 g/mol

VQ-033201

Reference Standard

4,4'-([1,1'-Biphenyl]-4,4'-diylbis(methylene))bis(thiomorpholine 1,1-dioxide)

4,4'-([1,1'-Biphenyl]-4,4'-diylbis(methylene))bis(thiomorpholine 1,1-dioxide)

CAS: 2756973-43-8
Formula: C₂₂H₂₈N₂O₄S₂
MW: 448.6 g/mol

VQ-037262

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