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Impurities & Reference Standards

Pharmacopoeial and non-pharmacopoeial impurities, metabolites, nitrosamines and working standards with characterisation data for QC and regulatory work.

28,554products

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2,746in stock

COA + SDSwith every lot

API Impurities 14,252 Pharmacopeial Impurities (EP / USP / BP) 4,401 Nitrosamine Impurities 650 Stable Isotope Labelled Standards (Deuterated, 13C, 15N) 1,612 Metabolites & Degradation Products 4,146 API Reference Standards 3,493

Reference Standard

4-Nitro-α-toluenesulfonyl chloride chemical structure

4-Nitro-α-toluenesulfonyl chloride

CAS: 4025-75-6
Formula: C₇H₆ClNO₄S
MW: 235.65 g/mol

VQ-033990

Reference Standard

4-Nitroaniline Hydrochloride chemical structure

4-Nitroaniline Hydrochloride

CAS: 15873-51-5
Formula: C₆H₇ClN₂O₂
MW: 174.58 g/mol

VQ-039323

Reference Standard

4-Nitroaniline-2,3,5,6-d4 chemical structure

4-Nitroaniline-2,3,5,6-d4

CAS: 64164-08-5
Formula: C₆H₆N₂O₂
MW: 142.15 g/mol

VQ-041167

Reference Standard

4-Nitrobenzenethiol chemical structure

4-Nitrobenzenethiol

CAS: 1849-36-1
Formula: C₆H₅NO₂S
MW: 155.18 g/mol

VQ-049494

Reference Standard

4-Nitrobenzoyl Varenicline chemical structure

4-Nitrobenzoyl Varenicline

CAS: 1329651-19-5
Formula: C₂₀H₁₆N₄O₄
MW: 376.4 g/mol

VQ-028645

Reference Standard

4-Nitrobenzyl (2S,4R)-2-(hydroxymethyl)-4-((methylsulfonyl)oxy)pyrrolidine-1-carboxylate chemical structure

4-Nitrobenzyl (2S,4R)-2-(hydroxymethyl)-4-((methylsulfonyl)oxy)pyrrolidine-1-carboxylate

CAS: 127626-37-3
Formula: C₁₄H₁₈N₂O₈S
MW: 374.37 g/mol

VQ-052041

Reference Standard

4-Nitrobenzyl (2S,4S)-2-(dimethylcarbamoyl)-4-mercaptopyrrolidine-1-carboxylate chemical structure

4-Nitrobenzyl (2S,4S)-2-(dimethylcarbamoyl)-4-mercaptopyrrolidine-1-carboxylate

CAS: 96034-64-9
Formula: C₁₅H₁₉N₃O₅S
MW: 353.4 g/mol

VQ-049046

Reference Standard

4-Nitrobenzyl (4R,5R,6S)-3-[(diphenylphosphono)oxy]-6-[(R)-1-hydroxyethyl]-4-methyl-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate chemical structure

4-Nitrobenzyl (4R,5R,6S)-3-[(diphenylphosphono)oxy]-6-[(R)-1-hydroxyethyl]-4-methyl-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate

CAS: 90776-59-3
Formula: C₂₉H₂₇N₂O₁₀P
MW: 594.5 g/mol

VQ-049047

Reference Standard

4-Nitrobenzyl 2-diazo-4-((2R,3S)-3-((R)-1-hydroxyethyl)-4-oxoazetidin-2-yl)-3-oxobutanoate chemical structure

4-Nitrobenzyl 2-diazo-4-((2R,3S)-3-((R)-1-hydroxyethyl)-4-oxoazetidin-2-yl)-3-oxobutanoate

CAS: 74288-39-4
Formula: C₁₆H₁₆N₄O₇
MW: 376.32 g/mol

VQ-037680

Reference Standard

4-Nitroguaiacol chemical structure

4-Nitroguaiacol

CAS: 3251-56-7
Formula: C₇H₇NO₄
MW: 169.13 g/mol

VQ-039118

Reference Standard

4-Nitrophenyl (4-(3-oxomorpholino)phenyl)carbamate chemical structure

4-Nitrophenyl (4-(3-oxomorpholino)phenyl)carbamate

CAS: 635301-86-9
Formula: C₁₇H₁₅N₃O₆
MW: 357.32 g/mol

VQ-038471

Reference Standard

4-Nitrophenyl 2-((furan-2-ylmethyl)sulfonyl)acetate chemical structure

4-Nitrophenyl 2-((furan-2-ylmethyl)sulfonyl)acetate

CAS: 163802-30-0
Formula: C₁₃H₁₁NO₇S
MW: 325.3 g/mol

VQ-037865

Reference Standard

4-Nitroso Sulfamethoxazole chemical structure

4-Nitroso Sulfamethoxazole

CAS: 131549-85-4
Formula: C₁₀H₉N₃O₄S
MW: 267.26 g/mol

VQ-033979

Reference Standard

4-Nitrosobenzenamine chemical structure

4-Nitrosobenzenamine

CAS: 659-49-4
Formula: C₆H₆N₂O
MW: 122.12 g/mol

VQ-040537

Reference Standard

4-Nitrosodiphenylamine chemical structure

4-Nitrosodiphenylamine

CAS: 156-10-5
Formula: C₁₂H₁₀N₂O
MW: 198.22 g/mol

VQ-041094

Reference Standard

4-Nitrosomethylaminopyridine chemical structure

4-Nitrosomethylaminopyridine

CAS: 16219-99-1
Formula: C₆H₇N₃O
MW: 137.14 g/mol

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Reference Standard

4-O-Methyl-D-glucuronic Acid chemical structure

4-O-Methyl-D-glucuronic Acid

CAS: 4120-73-4
Formula: C₇H₁₂O₇
MW: 208.17 g/mol

VQ-032359

Reference Standard

4-O-Methylated opicapone

4-O-Methylated opicapone

CAS: 1428009-81-7
Formula: C₁₆H₁₂Cl₂N₄O₆
MW: 427.19 g/mol

VQ-038778

Reference Standard

4-Octanoylphenethyl acetate chemical structure

4-Octanoylphenethyl acetate

CAS: 162358-03-4
Formula: C₁₈H₂₆O₃
MW: 290.4 g/mol

VQ-037288

Reference Standard

4-Oleoylmorpholine chemical structure

4-Oleoylmorpholine

CAS: 5299-52-5
Formula: C₂₂H₄₁NO₂
MW: 351.6 g/mol

VQ-040474

Reference Standard

4-Oxo-1,4-dihydroquinoline-3-carboxylic Acid chemical structure

4-Oxo-1,4-dihydroquinoline-3-carboxylic Acid

CAS: 13721-01-2
Formula: C₁₀H₇NO₃
MW: 189.17 g/mol

VQ-031335

Reference Standard

4-Oxo-3-[(Phenylmethyl)oxy]-4H-pyran-2-carboxylic acid chemical structure

4-Oxo-3-[(Phenylmethyl)oxy]-4H-pyran-2-carboxylic acid

CAS: 119736-16-2
Formula: C₁₃H₁₀O₅
MW: 246.21 g/mol

VQ-043922

Reference Standard

4-Oxo-6-(2-oxo-5-vinylpyrrolidin-1-yl)hexanoic Acid chemical structure

4-Oxo-6-(2-oxo-5-vinylpyrrolidin-1-yl)hexanoic Acid

CAS: 2512190-67-7
Formula: C₁₂H₁₇NO₄
MW: 239.27 g/mol

VQ-024004

Reference Standard

4-Oxo-9-Cis Retinoic Acid chemical structure

4-Oxo-9-Cis Retinoic Acid

CAS: 150737-18-1
Formula: C₂₀H₂₆O₃
MW: 314.4 g/mol

VQ-026243

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