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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-(4-Carboxybenzyl)piperidine-4-carboxylic acid chemical structure

1-(4-Carboxybenzyl)piperidine-4-carboxylic acid

CAS: 1158699-78-5
Formula: C₁₄H₁₇NO₄
MW: 263.29 g/mol

VQ-041887

Reference Standard

1-(4-Chloro-2-(2-fluorobenzoyl)phenyl)-2-methyl-1H-imidazole-5-carboxylic Acid chemical structure

1-(4-Chloro-2-(2-fluorobenzoyl)phenyl)-2-methyl-1H-imidazole-5-carboxylic Acid

CAS: 151921-06-1
Formula: C₁₈H₁₂ClFN₂O₃
MW: 358.7 g/mol

VQ-044843

Reference Standard

1-(4-Chloro-3-(trifluoromethyl)phenyl)urea chemical structure

1-(4-Chloro-3-(trifluoromethyl)phenyl)urea

CAS: 343247-69-8
Formula: C₈H₆ClF₃N₂O
MW: 238.59 g/mol

VQ-028091

Reference Standard

1-(4-Chlorobenzyl)piperidine chemical structure

1-(4-Chlorobenzyl)piperidine

CAS: 59507-42-5
Formula: C₁₂H₁₆ClN
MW: 209.71 g/mol

VQ-041537

Reference Standard

1-(4-Chlorobutanoyl)-1H-indole-5-carbonitrile chemical structure

1-(4-Chlorobutanoyl)-1H-indole-5-carbonitrile

CAS: 2512200-37-0
Formula: C₁₃H₁₁ClN₂O
MW: 246.69 g/mol

VQ-042888

Reference Standard

1-(4-Chloromethyl-2-thiazoyl)guanidine Hydrochloride Salt chemical structure

1-(4-Chloromethyl-2-thiazoyl)guanidine Hydrochloride Salt

CAS: 69014-12-6
Formula: C₅H₈Cl₂N₄S
MW: 227.11 g/mol

VQ-037199

Reference Standard

1-(4-Chlorophenyl)-2-phenoxyethan-1-one chemical structure

1-(4-Chlorophenyl)-2-phenoxyethan-1-one

CAS: 41806-25-1
Formula: C₁₄H₁₁ClO₂
MW: 246.69 g/mol

VQ-048357

Reference Standard

1-(4-Chlorophenyl)-4-(3-chloropropyl)piperazine chemical structure

1-(4-Chlorophenyl)-4-(3-chloropropyl)piperazine

CAS: 6323-14-4
Formula: C₁₃H₁₈Cl₂N₂
MW: 273.2 g/mol

VQ-034406

Reference Standard

1-(4-Chlorophenyl)piperazine chemical structure

1-(4-Chlorophenyl)piperazine

CAS: 38212-33-8
Formula: C₁₀H₁₃ClN₂
MW: 196.67 g/mol

VQ-044433

Reference Standard

1-(4-Ethoxy-3-methoxyphenyl)-2-(methylsulfonyl)ethanamine chemical structure

1-(4-Ethoxy-3-methoxyphenyl)-2-(methylsulfonyl)ethanamine

CAS: 885268-06-4
Formula: C₁₂H₁₉NO₄S
MW: 273.35 g/mol

VQ-035776

Reference Standard

1-(4-Ethylphenyl)-2-methyl-2-propen-1-one chemical structure

1-(4-Ethylphenyl)-2-methyl-2-propen-1-one

CAS: 70639-76-8
Formula: C₁₂H₁₄O
MW: 174.24 g/mol

VQ-025554

Reference Standard

1-(4-Fluorobenzyl)-3-(4-((2-methylallyl)oxy)benzyl)-1-(1-methylpiperidin-4-yl)urea chemical structure

1-(4-Fluorobenzyl)-3-(4-((2-methylallyl)oxy)benzyl)-1-(1-methylpiperidin-4-yl)urea

CAS: 1246458-13-8
Formula: C₂₅H₃₂FN₃O₂
MW: 425.5 g/mol

VQ-033187

Reference Standard

1-(4-Fluorophenyl)-1,3-DihydroIsobenzofuran-5-Carbonitrile chemical structure

1-(4-Fluorophenyl)-1,3-DihydroIsobenzofuran-5-Carbonitrile

CAS: 64169-67-1
Formula: C₁₅H₁₀FNO
MW: 239.24 g/mol

VQ-022202

Reference Standard

1-(4-Fluorophenyl)but-3-en-1-one chemical structure

1-(4-Fluorophenyl)but-3-en-1-one

CAS: 61668-02-8
Formula: C₁₀H₉FO
MW: 164.18 g/mol

VQ-044894

Reference Standard

1-(4-Hydrazinylphenyl)-N-methylmethanesulfonamide chemical structure

1-(4-Hydrazinylphenyl)-N-methylmethanesulfonamide

CAS: 139272-29-0
Formula: C₈H₁₃N₃O₂S
MW: 215.28 g/mol

VQ-042317

Reference Standard

1-(4-Iodophenyl)-3-morpholino-5,6-dihydropyridin-2(1H)-one chemical structure

1-(4-Iodophenyl)-3-morpholino-5,6-dihydropyridin-2(1H)-one

CAS: 473927-69-4
Formula: C₁₅H₁₇IN₂O₂
MW: 384.21 g/mol

VQ-044496

Reference Standard

1-(4-Isobutylphenyl)ethanol chemical structure

1-(4-Isobutylphenyl)ethanol

CAS: 40150-92-3
Formula: C₁₂H₁₈O
MW: 178.27 g/mol

VQ-031132

Reference Standard

1-(4-Isopropyl-phenyl)-propan-1-one chemical structure

1-(4-Isopropyl-phenyl)-propan-1-one

CAS: 27465-52-7
Formula: C₁₂H₁₆O
MW: 176.25 g/mol

VQ-048230

Reference Standard

1-(4-Methoxyphenyl)-2-Benzyl Amino Propane chemical structure

1-(4-Methoxyphenyl)-2-Benzyl Amino Propane

CAS: 43229-65-8
Formula: C₁₇H₂₁NO
MW: 255.35 g/mol

VQ-025906

Reference Standard

1-(4-Methoxyphenyl)-6-(4-(2-methyl-6-oxopiperidin-1-yl)phenyl)-7-oxo-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxamide chemical structure

1-(4-Methoxyphenyl)-6-(4-(2-methyl-6-oxopiperidin-1-yl)phenyl)-7-oxo-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxamide

CAS: 2098457-92-0
Formula: C₂₆H₂₇N₅O₄
MW: 473.5 g/mol

VQ-020812

Reference Standard

1-(4-Methoxyphenyl)-6-(4-(5-methyl-2-oxopiperidin-1-yl)phenyl)-7-oxo-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxamide chemical structure

1-(4-Methoxyphenyl)-6-(4-(5-methyl-2-oxopiperidin-1-yl)phenyl)-7-oxo-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxamide

CAS: 1686149-74-5
Formula: C₂₆H₂₇N₅O₄
MW: 473.5 g/mol

VQ-020813

Reference Standard

1-(4-Methoxyphenyl)-7-oxo-6-(4-(2-oxoazepan-1-yl)phenyl)-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxamide chemical structure

1-(4-Methoxyphenyl)-7-oxo-6-(4-(2-oxoazepan-1-yl)phenyl)-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxamide

CAS: 1074549-87-3
Formula: C₂₆H₂₇N₅O₄
MW: 473.5 g/mol

VQ-043043

Reference Standard

1-(4-Methoxyphenyl)-7-oxo-6-(4-(2-oxopyrrolidin-1-yl)phenyl)-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxamide chemical structure

1-(4-Methoxyphenyl)-7-oxo-6-(4-(2-oxopyrrolidin-1-yl)phenyl)-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxamide

CAS: 1777781-49-3
Formula: C₂₄H₂₃N₅O₄
MW: 445.5 g/mol

VQ-029184

Reference Standard

1-(4-Methoxyphenyl)Acetophenone chemical structure

1-(4-Methoxyphenyl)Acetophenone

CAS: 1023-17-2
Formula: C₁₅H₁₄O₂
MW: 226.27 g/mol

VQ-040452

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