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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

Acarviosine-glucose chemical structure

Acarviosine-glucose

CAS: 68128-53-0
Formula: C₁₉H₃₃NO₁₃
MW: 483.5 g/mol

VQ-024124

Reference Standard

Acebutolol Hydrochloride - Impurity E (Hydrochloride Salt) chemical structure

Acebutolol Hydrochloride - Impurity E (Hydrochloride Salt)

CAS: 1432053-72-9
Formula: C₁₆H₂₇ClN₂O₃
MW: 330.8 g/mol

VQ-021404

Reference Standard

Acebutolol Hydrochloride - Impurity J (Hydrochloride Salt) chemical structure

Acebutolol Hydrochloride - Impurity J (Hydrochloride Salt)

CAS: 57898-79-0
Formula: C₁₇H₂₇ClN₂O₄
MW: 358.9 g/mol

VQ-021407

Reference Standard

Aceclofenac Tert-Butyl Ester chemical structure

Aceclofenac Tert-Butyl Ester

CAS: 139272-68-7
Formula: C₂₀H₂₁Cl₂NO₄
MW: 410.3 g/mol

VQ-021412

Reference Standard

Acedapsone chemical structure

CAS: 77-46-3
Formula: C₁₆H₁₆N₂O₄S
MW: 332.4 g/mol

VQ-036547

Reference Standard

Acediasulfone chemical structure

CAS: 80-03-5
Formula: C₁₄H₁₄N₂O₄S
MW: 306.34 g/mol

VQ-024127

Reference Standard

Acemetacin Impurity 1 chemical structure

Acemetacin Impurity 1

CAS: 77914-62-6
Formula: C₉H₁₀ClNO
MW: 183.63 g/mol

VQ-045364

Reference Standard

Acephylline chemical structure

CAS: 652-37-9
Formula: C₉H₁₀N₄O₄
MW: 238.2 g/mol

VQ-021398

Reference Standard

Acephylline Piperazinate chemical structure

Acephylline Piperazinate

CAS: 18833-13-1
Formula: C₁₃H₂₀N₆O₄
MW: 324.34 g/mol

VQ-035582

Reference Standard

Aceprometazine Maleate chemical structure

Aceprometazine Maleate

CAS: 7455-18-7
Formula: C₂₃H₂₆N₂O₅S
MW: 442.5 g/mol

VQ-041727

Reference Standard

Acetaminophen Dimer chemical structure

Acetaminophen Dimer

CAS: 98966-14-4
Formula: C₁₆H₁₆N₂O₄
MW: 300.31 g/mol

VQ-023464

Reference Standard

Acetazolamide chemical structure

CAS: 59-66-5
Formula: C₄H₆N₄O₃S₂
MW: 222.3 g/mol

VQ-020720

Reference Standard

Acetic 2-acetoxybenzoic anhydride chemical structure

Acetic 2-acetoxybenzoic anhydride

CAS: 18698-59-4
Formula: C₁₁H₁₀O₅
MW: 222.19 g/mol

VQ-035590

Reference Standard

Acetochlor ESA sodium salt chemical structure

Acetochlor ESA sodium salt

CAS: 947601-84-5
Formula: C₁₄H₂₀NNaO₅S
MW: 337.37 g/mol

VQ-039736

Reference Standard

Acetochlor OA chemical structure

CAS: 194992-44-4
Formula: C₁₄H₁₉NO₄
MW: 265.3 g/mol

VQ-039737

Reference Standard

Acetoguanide chemical structure

CAS: 16352-06-0
Formula: C₄H₆N₄O
MW: 126.12 g/mol

VQ-030095

Reference Standard

Acetomenaphthone chemical structure

Acetomenaphthone

CAS: 573-20-6
Formula: C₁₅H₁₄O₄
MW: 258.27 g/mol

VQ-035587

Reference Standard

Acetone phenylhydrazone chemical structure

Acetone phenylhydrazone

CAS: 103-02-6
Formula: C₉H₁₂N₂
MW: 148.2 g/mol

VQ-033761

Reference Standard

Acetone semicarbazone chemical structure

Acetone semicarbazone

CAS: 110-20-3
Formula: C₄H₉N₃O
MW: 115.13 g/mol

VQ-032776

Reference Standard

Acetonoxime chemical structure

CAS: 127-06-0
Formula: C₃H₇NO
MW: 73.09 g/mol

VQ-032377

Reference Standard

Acetoxybutyl Aminopurine chemical structure

Acetoxybutyl Aminopurine

CAS: 183475-21-0
Formula: C₁₁H₁₅N₅O₃
MW: 265.27 g/mol

VQ-037191

Reference Standard

Acetoxyvalerenic Acid chemical structure

Acetoxyvalerenic Acid

CAS: 84638-55-1
Formula: C₁₇H₂₄O₄
MW: 292.4 g/mol

VQ-034520

Reference Standard

Acetyl 4-Chloro Benzhydryl Piperazine

Acetyl 4-Chloro Benzhydryl Piperazine

CAS: 802859-64-9
Formula: C₁₉H₂₁ClN₂O
MW: 328.84 g/mol

VQ-035295

Reference Standard

Acetyl Clozapine chemical structure

Acetyl Clozapine

CAS: 1025951-76-1
Formula: C₂₀H₂₁ClN₄O
MW: 368.9 g/mol

VQ-035231

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