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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

5-trans-Cloprostenol chemical structure

5-trans-Cloprostenol

CAS: 57968-81-7
Formula: C₂₂H₂₉ClO₆
MW: 424.9 g/mol

VQ-025065

Reference Standard

5-Trityl-4,5,6,7-tetrahydrothieno[3,2-c]pyridine chemical structure

5-Trityl-4,5,6,7-tetrahydrothieno[3,2-c]pyridine

CAS: 109904-25-8
Formula: C₂₆H₂₃NS
MW: 381.5 g/mol

VQ-032345

Reference Standard

5-Trityl-5,6,7,7a-tetrahydrothieno[3,2-c]pyridin-2(4H)-one chemical structure

5-Trityl-5,6,7,7a-tetrahydrothieno[3,2-c]pyridin-2(4H)-one

CAS: 109904-26-9
Formula: C₂₆H₂₃NOS
MW: 397.5 g/mol

VQ-033285

Reference Standard

5,10-Methenyltetrahydrofolic Acid Impurity chemical structure

5,10-Methenyltetrahydrofolic Acid Impurity

CAS: 7444-29-3
Formula: C₂₀H₂₁N₇O₆
MW: 455.4 g/mol

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Reference Standard

5,16-Androstadien-3-ol chemical structure

5,16-Androstadien-3-ol

CAS: 1224-94-8
Formula: C₁₉H₂₈O
MW: 272.4 g/mol

VQ-028987

Reference Standard

5,5-Dibenzylimidazolidine-2,4-dione chemical structure

5,5-Dibenzylimidazolidine-2,4-dione

CAS: 23186-94-9
Formula: C₁₇H₁₆N₂O₂
MW: 280.32 g/mol

VQ-035498

Reference Standard

5,5'-(Oxybis(methylene))bis(benzo[d][1,3]dioxole)

5,5'-(Oxybis(methylene))bis(benzo[d][1,3]dioxole)

CAS: 109600-72-8
Formula: C₁₆H₁₄O₅
MW: 286.3 g/mol

VQ-033217

Reference Standard

5,5'-Methylenebis(2-((1-(1-(4-fluorobenzyl)-1H-benzo[d]imidazol-2-yl)piperidin-4-yl)(methyl)amino)pyrimidin-4(3H)-one) chemical structure

5,5'-Methylenebis(2-((1-(1-(4-fluorobenzyl)-1H-benzo[d]imidazol-2-yl)piperidin-4-yl)(methyl)amino)pyrimidin-4(3H)-one)

CAS: 935860-13-2
Formula: C₄₉H₅₀F₂N₁₂O₂
MW: 877 g/mol

VQ-038463

Reference Standard

5,5'-Methylenebis(3-isopropyl-6-(((S)-1-phenylethyl)amino)pyrimidine-2,4(1H,3H)-dione)

5,5'-Methylenebis(3-isopropyl-6-(((S)-1-phenylethyl)amino)pyrimidine-2,4(1H,3H)-dione)

CAS: 3067752-16-0
Formula: C₃₁H₃₈N₆O₄
MW: 558.67 g/mol

VQ-049020

Reference Standard

5,6-Dehydro-N-methyl Desloratadine chemical structure

5,6-Dehydro-N-methyl Desloratadine

CAS: 117811-18-4
Formula: C₂₀H₁₉ClN₂
MW: 322.8 g/mol

VQ-036628

Reference Standard

5,6-Diamino-1-methylpyrimidine-2,4(1H,3H)-dione chemical structure

5,6-Diamino-1-methylpyrimidine-2,4(1H,3H)-dione

CAS: 6972-82-3
Formula: C₅H₈N₄O₂
MW: 156.14 g/mol

VQ-038054

Reference Standard

5,6-Diamino-1,3-dimethyl Uracil chemical structure

5,6-Diamino-1,3-dimethyl Uracil

CAS: 5440-00-6
Formula: C₆H₁₀N₄O₂
MW: 170.17 g/mol

VQ-025848

Reference Standard

5,6-Dichloro-2,4-Pyrimidinediamine chemical structure

5,6-Dichloro-2,4-Pyrimidinediamine

CAS: 89033-89-6
Formula: C₄H₄Cl₂N₄
MW: 179 g/mol

VQ-023147

Reference Standard

5,6-Dichloro-N-(4-(4-chlorothiophen-2-yl)-5-(4-cyclohexylpiperazin-1-yl)thiazol-2-yl)nicotinamide chemical structure

5,6-Dichloro-N-(4-(4-chlorothiophen-2-yl)-5-(4-cyclohexylpiperazin-1-yl)thiazol-2-yl)nicotinamide

CAS: 570403-04-2
Formula: C₂₃H₂₄Cl₃N₅OS₂
MW: 557 g/mol

VQ-047492

Reference Standard

5,6-Dichloro-N-isopropyl-1H-benzo[d]imidazol-2-amine chemical structure

5,6-Dichloro-N-isopropyl-1H-benzo[d]imidazol-2-amine

CAS: 176161-55-0
Formula: C₁₀H₁₁Cl₂N₃
MW: 244.12 g/mol

VQ-028966

Reference Standard

5,6-Dichloronicotinic acid chemical structure

5,6-Dichloronicotinic acid

CAS: 41667-95-2
Formula: C₆H₃Cl₂NO₂
MW: 192 g/mol

VQ-026899

Reference Standard

5,6-Dichloropyrimidine-4-carboxylic Acid chemical structure

5,6-Dichloropyrimidine-4-carboxylic Acid

CAS: 914916-97-5
Formula: C₅H₂Cl₂N₂O₂
MW: 192.98 g/mol

VQ-042633

Reference Standard

5,6-Diethyl-2,3-dihydro-1H-inden-1-one chemical structure

5,6-Diethyl-2,3-dihydro-1H-inden-1-one

CAS: 312753-51-8
Formula: C₁₃H₁₆O
MW: 188.26 g/mol

VQ-032619

Reference Standard

5,6-Diethyl-2,3-dihydro-1H-Inden-2-Amine Hydrochloride chemical structure

5,6-Diethyl-2,3-dihydro-1H-Inden-2-Amine Hydrochloride

CAS: 312753-53-0
Formula: C₁₃H₂₀ClN
MW: 225.76 g/mol

VQ-022842

Reference Standard

5,6-Dihydro Tofacitinib chemical structure

5,6-Dihydro Tofacitinib

CAS: 1640972-35-5
Formula: C₁₆H₂₂N₆O
MW: 314.39 g/mol

VQ-028416

Reference Standard

5,6-Dihydro-6-methyluracil chemical structure

5,6-Dihydro-6-methyluracil

CAS: 2434-49-3
Formula: C₅H₈N₂O₂
MW: 128.13 g/mol

VQ-044497

Reference Standard

5,6-Dihydroabiraterone chemical structure

5,6-Dihydroabiraterone

CAS: 219843-75-1
Formula: C₂₄H₃₃NO
MW: 351.5 g/mol

VQ-024111

Reference Standard

5,6-Dihydrobiopterin chemical structure

5,6-Dihydrobiopterin

CAS: 251310-15-3
Formula: C₉H₁₃N₅O₃
MW: 239.23 g/mol

VQ-027983

Reference Standard

5,6-Dihydrouridine chemical structure

5,6-Dihydrouridine

CAS: 5627-05-4
Formula: C₉H₁₄N₂O₆
MW: 246.22 g/mol

VQ-042765

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