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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-[2-(5-Ethyl-2-pyridinyl)ethoxy]benzenemethanol chemical structure

4-[2-(5-Ethyl-2-pyridinyl)ethoxy]benzenemethanol

CAS: 144842-17-1
Formula: C₁₆H₁₉NO₂
MW: 257.33 g/mol

VQ-033198

Reference Standard

4-[2-(Diethylamino)ethoxy]benzophenone chemical structure

4-[2-(Diethylamino)ethoxy]benzophenone

CAS: 796-77-0
Formula: C₁₉H₂₃NO₂
MW: 297.4 g/mol

VQ-021195

Reference Standard

4-[4-(3-Aminopropylamino)phenyl]morpholin-3-one chemical structure

4-[4-(3-Aminopropylamino)phenyl]morpholin-3-one

CAS: 1816946-19-6
Formula: C₁₃H₁₉N₃O₂
MW: 249.31 g/mol

VQ-045368

Reference Standard

4-[4-(4-Nitrophenyl)-1-piperazinyl]phenol chemical structure

4-[4-(4-Nitrophenyl)-1-piperazinyl]phenol

CAS: 112559-81-6
Formula: C₁₆H₁₇N₃O₃
MW: 299.32 g/mol

VQ-041566

Reference Standard

4-[4-(Trifluoromethoxy)phenoxy]piperidine chemical structure

4-[4-(Trifluoromethoxy)phenoxy]piperidine

CAS: 287952-67-4
Formula: C₁₂H₁₄F₃NO₂
MW: 261.24 g/mol

VQ-025240

Reference Standard

4-[8-Amino-3-(3,4-dihydro-2H-pyrrol-5-yl)imidazo[1,5-a]pyrazin-1-yl]-N-2-pyridinylbenzamide chemical structure

4-[8-Amino-3-(3,4-dihydro-2H-pyrrol-5-yl)imidazo[1,5-a]pyrazin-1-yl]-N-2-pyridinylbenzamide

CAS: 2230757-49-8
Formula: C₂₂H₁₉N₇O
MW: 397.4 g/mol

VQ-021392

Reference Standard

4-{(E)-[(2-Fluorophenyl)imino]methyl}phenol chemical structure

4-{(E)-[(2-Fluorophenyl)imino]methyl}phenol

CAS: 1829558-56-6
Formula: C₁₃H₁₀FNO
MW: 215.22 g/mol

VQ-030655

Reference Standard

4-{[(p-Fluorophenyl)imino]methyl}phenol chemical structure

4-{[(p-Fluorophenyl)imino]methyl}phenol

CAS: 3382-63-6
Formula: C₁₃H₁₀FNO
MW: 215.22 g/mol

VQ-037174

Reference Standard

4-Acetamido-3-chlorophenyl acetate chemical structure

4-Acetamido-3-chlorophenyl acetate

CAS: 60144-85-6
Formula: C₁₀H₁₀ClNO₃
MW: 227.64 g/mol

VQ-042576

Reference Standard

4-Acetamido-5-chloro-2-methoxybenzoic acid chemical structure

4-Acetamido-5-chloro-2-methoxybenzoic acid

CAS: 24201-13-6
Formula: C₁₀H₁₀ClNO₄
MW: 243.64 g/mol

VQ-049092

Reference Standard

4-Acetamido-5-chloro-2,3-dihydrobenzofuran-7-carboxylic Acid chemical structure

4-Acetamido-5-chloro-2,3-dihydrobenzofuran-7-carboxylic Acid

CAS: 338791-13-2
Formula: C₁₁H₁₀ClNO₄
MW: 255.65 g/mol

VQ-041752

Reference Standard

4-Acetoxy Midazolam chemical structure

4-Acetoxy Midazolam

CAS: 59468-84-7
Formula: C₂₀H₁₅ClFN₃O₂
MW: 383.8 g/mol

VQ-043693

Reference Standard

4-Acetyl Ramelteon chemical structure

4-Acetyl Ramelteon

CAS: 1346598-94-4
Formula: C₁₈H₂₃NO₃
MW: 301.4 g/mol

VQ-043272

Reference Standard

4-Acetyl-2-chlorobenzonitrile chemical structure

4-Acetyl-2-chlorobenzonitrile

CAS: 101667-74-7
Formula: C₉H₆ClNO
MW: 179.6 g/mol

VQ-036565

Reference Standard

4-Acetyl-2-methylbenzonitrile chemical structure

4-Acetyl-2-methylbenzonitrile

CAS: 1138444-80-0
Formula: C₁₀H₉NO
MW: 159.18 g/mol

VQ-045125

Reference Standard

4-Acetyl-2-propyl-1H-imidazole-5-carboxylic Acid Ethyl Ester chemical structure

4-Acetyl-2-propyl-1H-imidazole-5-carboxylic Acid Ethyl Ester

CAS: 144690-07-3
Formula: C₁₁H₁₆N₂O₃
MW: 224.26 g/mol

VQ-032234

Reference Standard

4-Amino -1-(4-nitrobenzyl)-1,2,4-triazolium bromide chemical structure

4-Amino -1-(4-nitrobenzyl)-1,2,4-triazolium bromide

CAS: 6085-99-0
Formula: C₉H₁₀BrN₅O₂
MW: 300.11 g/mol

VQ-032592

Reference Standard

4-Amino-1-(3,5-di-O-acetyl-2-deoxy-D-erythro-pentofuranosyl)-1,3,5-triazin-2(1H)-one chemical structure

4-Amino-1-(3,5-di-O-acetyl-2-deoxy-D-erythro-pentofuranosyl)-1,3,5-triazin-2(1H)-one

CAS: 22432-93-5
Formula: C₁₂H₁₆N₄O₆
MW: 312.28 g/mol

VQ-036595

Reference Standard

4-Amino-1-benzyl-piperidine-4-carboxylic acid chemical structure

4-Amino-1-benzyl-piperidine-4-carboxylic acid

CAS: 39143-25-4
Formula: C₁₃H₁₈N₂O₂
MW: 234.29 g/mol

VQ-021979

Reference Standard

4-Amino-1-methyl-3-(2-methylpropyl)-1H-pyrazole-5-carboxamide chemical structure

4-Amino-1-methyl-3-(2-methylpropyl)-1H-pyrazole-5-carboxamide

CAS: 268204-00-8
Formula: C₉H₁₆N₄O
MW: 196.25 g/mol

VQ-042164

Reference Standard

4-Amino-1-methyl-3-propyl-1H-pyrazole-5-carboxamide Hydrochloride chemical structure

4-Amino-1-methyl-3-propyl-1H-pyrazole-5-carboxamide Hydrochloride

CAS: 247584-10-7
Formula: C₈H₁₅ClN₄O
MW: 218.68 g/mol

VQ-033837

Reference Standard

4-Amino-1-methyl-5-propyl-1H-pyrazole-3-carboxamide chemical structure

4-Amino-1-methyl-5-propyl-1H-pyrazole-3-carboxamide

CAS: 247583-78-4
Formula: C₈H₁₄N₄O
MW: 182.22 g/mol

VQ-043296

Reference Standard

4-Amino-2-(1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethyl)isoindoline-1,3-dione chemical structure

4-Amino-2-(1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethyl)isoindoline-1,3-dione

CAS: 253168-83-1
Formula: C₂₀H₂₂N₂O₆S
MW: 418.5 g/mol

VQ-024335

Reference Standard

4-Amino-2-(2,6-dioxopiperidin-3-yl)-5,6,7-trihydroxyisoindoline-1,3-dione chemical structure

4-Amino-2-(2,6-dioxopiperidin-3-yl)-5,6,7-trihydroxyisoindoline-1,3-dione

CAS: 1795373-44-2
Formula: C₁₃H₁₁N₃O₇
MW: 321.24 g/mol

VQ-043263

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