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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-Chloro-3-nitrobenzoic acid methyl ester chemical structure

4-Chloro-3-nitrobenzoic acid methyl ester

CAS: 14719-83-6
Formula: C₈H₆ClNO₄
MW: 215.59 g/mol

VQ-026914

Reference Standard

4-Chloro-3-pyridazinecarboxylic acid chemical structure

4-Chloro-3-pyridazinecarboxylic acid

CAS: 1261798-87-1
Formula: C₅H₃ClN₂O₂
MW: 158.54 g/mol

VQ-036644

Reference Standard

4-Chloro-3-sulfamoylbenzoyl Chloride chemical structure

4-Chloro-3-sulfamoylbenzoyl Chloride

CAS: 70049-77-3
Formula: C₇H₅Cl₂NO₃S
MW: 254.09 g/mol

VQ-031197

Reference Standard

4-Chloro-4-fluorobutyrophenone chemical structure

4-Chloro-4-fluorobutyrophenone

CAS: 3874-54-2
Formula: C₁₀H₁₀ClFO
MW: 200.64 g/mol

VQ-026044

Reference Standard

4-Chloro-4-methyl-5-methylene-1,3-dioxolan-2-one chemical structure

4-Chloro-4-methyl-5-methylene-1,3-dioxolan-2-one

CAS: 95579-71-8
Formula: C₅H₅ClO₃
MW: 148.54 g/mol

VQ-026994

Reference Standard

4-Chloro-4′-methoxybenzophenone chemical structure

4-Chloro-4′-methoxybenzophenone

CAS: 10547-60-1
Formula: C₁₄H₁₁ClO₂
MW: 246.69 g/mol

VQ-030697

Reference Standard

4-Chloro-5-fluoro-2-methoxypyrimidine chemical structure

4-Chloro-5-fluoro-2-methoxypyrimidine

CAS: 1801-06-5
Formula: C₅H₄ClFN₂O
MW: 162.55 g/mol

VQ-032323

Reference Standard

4-Chloro-5-nitro-2-(propylthio)pyrimidine chemical structure

4-Chloro-5-nitro-2-(propylthio)pyrimidine

CAS: 2518331-26-3
Formula: C₇H₈ClN₃O₂S
MW: 233.68 g/mol

VQ-034915

Reference Standard

4-Chloro-6-methoxy-2-(propylthio)-5-pyrimidinamine chemical structure

4-Chloro-6-methoxy-2-(propylthio)-5-pyrimidinamine

CAS: 1431867-40-1
Formula: C₈H₁₂ClN₃OS
MW: 233.72 g/mol

VQ-042514

Reference Standard

4-Chloro-6-methoxyquinolin-7-ol chemical structure

4-Chloro-6-methoxyquinolin-7-ol

CAS: 205448-31-3
Formula: C₁₀H₈ClNO₂
MW: 209.63 g/mol

VQ-029575

Reference Standard

4-Chloro-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidine chemical structure

4-Chloro-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidine

CAS: 16372-08-0
Formula: C₆H₆ClN₃
MW: 155.58 g/mol

VQ-034308

Reference Standard

4-Chloro-7-((2-(trimethylsilyl)ethoxy)methyl)-7H-pyrrolo[2,3-d]pyrimidine chemical structure

4-Chloro-7-((2-(trimethylsilyl)ethoxy)methyl)-7H-pyrrolo[2,3-d]pyrimidine

CAS: 941685-26-3
Formula: C₁₂H₁₈ClN₃OSi
MW: 283.83 g/mol

VQ-027953

Reference Standard

4-Chloro-7-(3-chloropropoxy)-3-cyano-6-methoxyquinoline chemical structure

4-Chloro-7-(3-chloropropoxy)-3-cyano-6-methoxyquinoline

CAS: 214470-68-5
Formula: C₁₄H₁₂Cl₂N₂O₂
MW: 311.2 g/mol

VQ-029484

Reference Standard

4-Chloro-7-methoxy-quinolin-6-ol chemical structure

4-Chloro-7-methoxy-quinolin-6-ol

CAS: 205448-74-4
Formula: C₁₀H₈ClNO₂
MW: 209.63 g/mol

VQ-036075

Reference Standard

4-Chloro-7,8,10,11,13,14-hexahydro-[1,4,7,10]tetraoxacyclododecino[2,3-g]quinazoline chemical structure

4-Chloro-7,8,10,11,13,14-hexahydro-[1,4,7,10]tetraoxacyclododecino[2,3-g]quinazoline

CAS: 1204313-58-5
Formula: C₁₄H₁₅ClN₂O₄
MW: 310.73 g/mol

VQ-031150

Reference Standard

4-Chloro-N-(2-(2-oxo-1,2-dihydroquinolin-4-yl)ethyl)benzamide chemical structure

4-Chloro-N-(2-(2-oxo-1,2-dihydroquinolin-4-yl)ethyl)benzamide

CAS: 100342-53-8
Formula: C₁₈H₁₅ClN₂O₂
MW: 326.8 g/mol

VQ-023618

Reference Standard

4-Chloro-N-(2-chloropropyl)benzeneethanamine Hydrochloride chemical structure

4-Chloro-N-(2-chloropropyl)benzeneethanamine Hydrochloride

CAS: 953789-37-2
Formula: C₁₁H₁₆Cl₃N
MW: 268.6 g/mol

VQ-026504

Reference Standard

4-Chloro-N-(6-methoxy-3-pyridyl)anthranilic acid chemical structure

4-Chloro-N-(6-methoxy-3-pyridyl)anthranilic acid

CAS: 6626-07-9
Formula: C₁₃H₁₁ClN₂O₃
MW: 278.69 g/mol

VQ-041774

Reference Standard

4-Chloro-N-methyl-2-pyridinecarboxamide chemical structure

4-Chloro-N-methyl-2-pyridinecarboxamide

CAS: 220000-87-3
Formula: C₇H₇ClN₂O
MW: 170.59 g/mol

VQ-033924

Reference Standard

4-Chloro-N-phenylaniline chemical structure

4-Chloro-N-phenylaniline

CAS: 1205-71-6
Formula: C₁₂H₁₀ClN
MW: 203.67 g/mol

VQ-039965

Reference Standard

4-Chloro-β-(isocyanatomethyl)benzenepropanoic Acid chemical structure

4-Chloro-β-(isocyanatomethyl)benzenepropanoic Acid

CAS: 2505131-83-7
Formula: C₁₁H₁₀ClNO₃
MW: 239.65 g/mol

VQ-029350

Reference Standard

4-Chlorobenzotrichloride chemical structure

4-Chlorobenzotrichloride

CAS: 5216-25-1
Formula: C₇H₄Cl₄
MW: 229.9 g/mol

VQ-023388

Reference Standard

4-Chlorobutanol Aminocarbinol Adduct chemical structure

4-Chlorobutanol Aminocarbinol Adduct

CAS: 1632028-59-1
Formula: C₁₈H₁₈Cl₂F₃NO₃
MW: 424.2 g/mol

VQ-036897

Reference Standard

4-Chlorobutyl Acetate chemical structure

4-Chlorobutyl Acetate

CAS: 6962-92-1
Formula: C₆H₁₁ClO₂
MW: 150.6 g/mol

VQ-032633

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