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Impurities & Reference Standards

API Impurities

Source 1942 api impurities for research, QC and production, documented with COA and SDS.

14,098products

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Reference Standard

((2R,3S,4R,5R)-5-(2,4-Dioxo-3,4-dihydropyrimidin-1(2H)-yl)-3,4-dihydroxytetrahydrofuran-2-yl)methyl hydrogen phosphate anhydride, disodium chemical structure

((2R,3S,4R,5R)-5-(2,4-Dioxo-3,4-dihydropyrimidin-1(2H)-yl)-3,4-dihydroxytetrahydrofuran-2-yl)methyl hydrogen phosphate anhydride, disodium

CAS: 221169-12-6
Formula: C₁₈H₂₂N₄Na₂O₁₇P₂
MW: 674.3 g/mol

VQ-036740

Reference Standard

((2R,3S,5R)-3-Acetoxy-5-(5-methyl-2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl)tetrahydrofuran-2-yl)methyl acetate chemical structure

((2R,3S,5R)-3-Acetoxy-5-(5-methyl-2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl)tetrahydrofuran-2-yl)methyl acetate

CAS: 6979-97-1
Formula: C₁₄H₁₈N₂O₇
MW: 326.3 g/mol

VQ-021892

Reference Standard

((2R,3S,5S)-3-Acetoxy-5-(4-amino-2-oxo-1,3,5-triazin-1(2H)-yl)tetrahydrofuran-2-yl)methyl acetate chemical structure

((2R,3S,5S)-3-Acetoxy-5-(4-amino-2-oxo-1,3,5-triazin-1(2H)-yl)tetrahydrofuran-2-yl)methyl acetate

CAS: 1254186-96-3
Formula: C₁₂H₁₆N₄O₆
MW: 312.28 g/mol

VQ-030098

Reference Standard

((2R,3S)-3-(Benzoyloxy)-4,4-difluoro-5-oxotetrahydrofuran-2-yl)methyl Benzoate chemical structure

((2R,3S)-3-(Benzoyloxy)-4,4-difluoro-5-oxotetrahydrofuran-2-yl)methyl Benzoate

CAS: 122111-02-8
Formula: C₁₉H₁₄F₂O₆
MW: 376.3 g/mol

VQ-030960

Reference Standard

((2R,5S)-5-(4-Amino-5-fluoro-2-oxopyrimidin-1(2H)-yl)-1,3-oxathiolan-2-yl)methyl hydrogen ((((R)-1-(6-amino-9H-purin-9-yl)propan-2-yl)oxy)methyl)phosphonate chemical structure

((2R,5S)-5-(4-Amino-5-fluoro-2-oxopyrimidin-1(2H)-yl)-1,3-oxathiolan-2-yl)methyl hydrogen ((((R)-1-(6-amino-9H-purin-9-yl)propan-2-yl)oxy)methyl)phosphonate

CAS: 1962114-95-9
Formula: C₁₇H₂₂FN₈O₆PS
MW: 516.4 g/mol

VQ-036980

Reference Standard

((2S,3R)-3-(Benzoyloxy)-4,4-difluoro-5-oxotetrahydrofuran-2-yl)methyl benzoate chemical structure

((2S,3R)-3-(Benzoyloxy)-4,4-difluoro-5-oxotetrahydrofuran-2-yl)methyl benzoate

CAS: 1217452-91-9
Formula: C₁₉H₁₄F₂O₆
MW: 376.3 g/mol

VQ-037498

Reference Standard

((2S,4R)-2-((1H-1,2,4-Triazol-1-yl)methyl)-2-(2,4-dichlorophenyl)-1,3-dioxolan-4-yl)methanol chemical structure

((2S,4R)-2-((1H-1,2,4-Triazol-1-yl)methyl)-2-(2,4-dichlorophenyl)-1,3-dioxolan-4-yl)methanol

CAS: 172587-60-9
Formula: C₁₃H₁₃Cl₂N₃O₃
MW: 330.16 g/mol

VQ-031311

Reference Standard

((2S,4R)-2-((1H-Imidazol-1-yl)methyl)-2-(2,4-dichlorophenyl)-1,3-dioxolan-4-yl)methanol chemical structure

((2S,4R)-2-((1H-Imidazol-1-yl)methyl)-2-(2,4-dichlorophenyl)-1,3-dioxolan-4-yl)methanol

CAS: 170210-49-8
Formula: C₁₄H₁₄Cl₂N₂O₃
MW: 329.2 g/mol

VQ-026288

Reference Standard

((2S,4S)-2-(Bromomethyl)-2-(2,4-dichlorophenyl)-1,3-dioxolan-4-yl)methyl benzoate chemical structure

((2S,4S)-2-(Bromomethyl)-2-(2,4-dichlorophenyl)-1,3-dioxolan-4-yl)methyl benzoate

CAS: 170210-46-5
Formula: C₁₈H₁₅BrCl₂O₄
MW: 446.1 g/mol

VQ-044517

Reference Standard

((2S)-3-((1-Ethyl-2,5-dioxopyrrolidin-3-yl)thio)-2-methylpropanoyl)-L-proline chemical structure

((2S)-3-((1-Ethyl-2,5-dioxopyrrolidin-3-yl)thio)-2-methylpropanoyl)-L-proline

CAS: 185804-96-0
Formula: C₁₅H₂₂N₂O₅S
MW: 342.4 g/mol

VQ-044051

Reference Standard

((3-Methyl-1,2,3,4-tetrahydroquinolin-8-yl)sulfonyl)-L-arginine chemical structure

((3-Methyl-1,2,3,4-tetrahydroquinolin-8-yl)sulfonyl)-L-arginine

CAS: 184043-01-4
Formula: C₁₆H₂₅N₅O₄S
MW: 383.5 g/mol

VQ-043749

Reference Standard

((3AR,4R,6R,6aR)-6-(2,4-dioxo-3,4-Dihydropyrimidin-1(2H)-yl)-2,2-dimethyltetrahydrofuro[3,4-d][1,3]dioxol-4-yl)methyl isobutyrate chemical structure

((3AR,4R,6R,6aR)-6-(2,4-dioxo-3,4-Dihydropyrimidin-1(2H)-yl)-2,2-dimethyltetrahydrofuro[3,4-d][1,3]dioxol-4-yl)methyl isobutyrate

CAS: 2346620-53-7
Formula: C₁₆H₂₂N₂O₇
MW: 354.35 g/mol

VQ-038472

Reference Standard

((3R,5R)-5-((1H-1,2,4-Triazol-1-yl)methyl)-5-(2,4-difluorophenyl)tetrahydrofuran-3-yl)methyl 4-methylbenzenesulfonate chemical structure

((3R,5R)-5-((1H-1,2,4-Triazol-1-yl)methyl)-5-(2,4-difluorophenyl)tetrahydrofuran-3-yl)methyl 4-methylbenzenesulfonate

CAS: 159811-30-0
Formula: C₂₁H₂₁F₂N₃O₄S
MW: 449.5 g/mol

VQ-033246

Reference Standard

((3R,5R)-5-((1H-1,2,4-Triazol-1-yl)methyl)-5-(2,4-difluorophenyl)tetrahydrofuran-3-yl)methyl 4-methylbenzenesulfonate chemical structure

((3R,5R)-5-((1H-1,2,4-Triazol-1-yl)methyl)-5-(2,4-difluorophenyl)tetrahydrofuran-3-yl)methyl 4-methylbenzenesulfonate

CAS: 149809-42-7
Formula: C₂₁H₂₁F₂N₃O₄S
MW: 449.5 g/mol

VQ-033247

Reference Standard

((3S,4S)-4-(4-Fluorophenyl)-1-methylpiperidin-3-yl)methanol chemical structure

((3S,4S)-4-(4-Fluorophenyl)-1-methylpiperidin-3-yl)methanol

CAS: 100332-20-5
Formula: C₁₃H₁₈FNO
MW: 223.29 g/mol

VQ-043513

Reference Standard

((3S,5R)-5-(2,4-Difluorophenyl)-5-(iodomethyl)tetrahydrofuran-3-yl)methyl Isobutyrate chemical structure

((3S,5R)-5-(2,4-Difluorophenyl)-5-(iodomethyl)tetrahydrofuran-3-yl)methyl Isobutyrate

CAS: 1042398-26-4
Formula: C₁₆H₁₉F₂IO₃
MW: 424.22 g/mol

VQ-033255

Reference Standard

((4-(3-(3-Fluorophenyl)-5,5-dimethyl-4-oxo-4,5-dihydrofuran-2-yl)phenyl)sulfonyl)methyl acetate chemical structure

((4-(3-(3-Fluorophenyl)-5,5-dimethyl-4-oxo-4,5-dihydrofuran-2-yl)phenyl)sulfonyl)methyl acetate

CAS: 1778703-66-4
Formula: C₂₁H₁₉FO₆S
MW: 418.4 g/mol

VQ-027548

Reference Standard

((4R,5R)-2-(Dichloromethyl)-5-(4-(methylsulfonyl)phenyl)-4,5-dihydrooxazol-4-yl)methanol chemical structure

((4R,5R)-2-(Dichloromethyl)-5-(4-(methylsulfonyl)phenyl)-4,5-dihydrooxazol-4-yl)methanol

CAS: 126813-11-4
Formula: C₁₂H₁₃Cl₂NO₄S
MW: 338.2 g/mol

VQ-025806

Reference Standard

((5-Acetamido-2,4,6-triiodoisophthaloyl)bis(azanediyl))bis(propane-3,1,2-triyl) tetraacetate chemical structure

((5-Acetamido-2,4,6-triiodoisophthaloyl)bis(azanediyl))bis(propane-3,1,2-triyl) tetraacetate

CAS: 174416-65-0
Formula: C₂₄H₂₈I₃N₃O₁₁
MW: 915.2 g/mol

VQ-037720

Reference Standard

((5-Thiazolyl)methyl)-(4-nitrophenyl)carbonate chemical structure

((5-Thiazolyl)methyl)-(4-nitrophenyl)carbonate

CAS: 144163-97-3
Formula: C₁₁H₈N₂O₅S
MW: 280.26 g/mol

VQ-025072

Reference Standard

((7-(4-(4-(2,3-Dichlorophenyl)piperazin-1-yl)butoxy)-2-oxo-3,4-dihydroquinolin-1(2H)-yl)methoxy)methyl Dodecanoate

((7-(4-(4-(2,3-Dichlorophenyl)piperazin-1-yl)butoxy)-2-oxo-3,4-dihydroquinolin-1(2H)-yl)methoxy)methyl Dodecanoate

CAS: 1870867-21-2
Formula: C₃₇H₅₃Cl₂N₃O₅
MW: 690.7 g/mol

VQ-043049

Reference Standard

((7S,9AS)-Octahydropyrazino[2,1-c][1,4]oxazin-7-yl)methanol chemical structure

((7S,9AS)-Octahydropyrazino[2,1-c][1,4]oxazin-7-yl)methanol

CAS: 929047-53-0
Formula: C₈H₁₆N₂O₂
MW: 172.22 g/mol

VQ-036953

Reference Standard

((8R,9S,10R,13S,14S)-10,13-Dimethyl-3,17-dioxo-6,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-3H-cyclopenta[a]phenanthren-6-yl)methyl methanesulfonate chemical structure

((8R,9S,10R,13S,14S)-10,13-Dimethyl-3,17-dioxo-6,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-3H-cyclopenta[a]phenanthren-6-yl)methyl methanesulfonate

CAS: 861395-77-9
Formula: C₂₁H₂₈O₅S
MW: 392.5 g/mol

VQ-037172

Reference Standard

((R)-2-(2-Morpholinoacetamido)-4-phenylbutanoyl)-L-leucyl-L-phenylalanine chemical structure

((R)-2-(2-Morpholinoacetamido)-4-phenylbutanoyl)-L-leucyl-L-phenylalanine

CAS: 2049024-77-1
Formula: C₃₁H₄₂N₄O₆
MW: 566.7 g/mol

VQ-043761

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