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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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COA + SDSwith every lot

Reference Standard

Axitinib Z-isomer chemical structure

Axitinib Z-isomer

CAS: 885126-40-9
Formula: C₂₂H₁₈N₄OS
MW: 386.5 g/mol

VQ-024454

Reference Standard

Azacitidine Amine impurity 7 isomer chemical structure

Azacitidine Amine impurity 7 isomer

CAS: 206269-46-7
Formula: C₈H₁₂N₄O₅
MW: 244.2 g/mol

VQ-047505

Reference Standard

Azacitidine Impurity 4

Azacitidine Impurity 4

CAS: 2306050-24-6
Formula: C₂₅H₃₂N₄O₁₅
MW: 628.54 g/mol

VQ-047501

Reference Standard

Azacitidine Impurity C isomers chemical structure

Azacitidine Impurity C isomers

CAS: 2775292-15-2
Formula: C₉H₁₈N₄O₇
MW: 294.26 g/mol

VQ-035883

Reference Standard

Azacitidine Related Compound C (Isomer 3) chemical structure

Azacitidine Related Compound C (Isomer 3)

CAS: 2775292-14-1
Formula: C₇H₁₄N₄O₅
MW: 234.21 g/mol

VQ-024463

Reference Standard

Azacitidine Related Compound C (Isomer 4) chemical structure

Azacitidine Related Compound C (Isomer 4)

CAS: 1698011-17-4
Formula: C₇H₁₄N₄O₅
MW: 234.21 g/mol

VQ-024464

Reference Standard

Azadirachtin I chemical structure

CAS: 134788-16-2
Formula: C₃₂H₄₂O₁₂
MW: 618.7 g/mol

VQ-035887

Reference Standard

Azaerythromycin A 11,12-hydrogen borate chemical structure

Azaerythromycin A 11,12-hydrogen borate

CAS: 194809-66-0
Formula: C₃₇H₆₉BN₂O₁₃
MW: 760.8 g/mol

VQ-035046

Reference Standard

Azafenidin chemical structure

CAS: 68049-83-2
Formula: C₁₅H₁₃Cl₂N₃O₂
MW: 338.2 g/mol

VQ-034976

Reference Standard

Azasetron Impurity 1 chemical structure

Azasetron Impurity 1

CAS: 123040-79-9
Formula: C₁₀H₈ClNO₄
MW: 241.63 g/mol

VQ-045286

Reference Standard

Azelaic Acid Monoethyl Ester chemical structure

Azelaic Acid Monoethyl Ester

CAS: 1593-55-1
Formula: C₁₁H₂₀O₄
MW: 216.27 g/mol

VQ-021697

Reference Standard

Azelaic acid tetracarboxylic acid impurity chemical structure

Azelaic acid tetracarboxylic acid impurity

CAS: 855898-43-0
Formula: C₁₁H₁₆O₈
MW: 276.24 g/mol

VQ-024468

Reference Standard

Azelastine 3-Chloro-Isomer chemical structure

Azelastine 3-Chloro-Isomer

CAS: 37933-01-0
Formula: C₂₂H₂₄ClN₃O
MW: 381.9 g/mol

VQ-029326

Reference Standard

Azelastine 5-Member-Cyclic-Isomer HCl chemical structure

Azelastine 5-Member-Cyclic-Isomer HCl

CAS: 117078-70-3
Formula: C₂₂H₂₄ClN₃O
MW: 381.9 g/mol

VQ-021705

Reference Standard

Azilsartan Amide Medoxomil Impurity chemical structure

Azilsartan Amide Medoxomil Impurity

CAS: 1696392-12-7
Formula: C₂₉H₂₅N₃O₇
MW: 527.5 g/mol

In stock

Reference Standard

Azilsartan Amidoxime Impurity chemical structure

Azilsartan Amidoxime Impurity

CAS: 1449029-77-9
Formula: C₂₉H₂₆N₄O₇
MW: 542.5 g/mol

In stock

Reference Standard

Azilsartan Dimer chemical structure

Azilsartan Dimer

CAS: 1604812-35-2
Formula: C₃₅H₂₈N₄O₁₁
MW: 680.6 g/mol

VQ-020869

Reference Standard

Azilsartan Dimer Impurity chemical structure

Azilsartan Dimer Impurity

CAS: 1417576-02-3
Formula: C₅₅H₄₂N₈O₁₃
MW: 1023 g/mol

In stock

Reference Standard

Azilsartan Ethyl Ring-opening Impurity chemical structure

Azilsartan Ethyl Ring-opening Impurity

CAS: 1403474-75-8
Formula: C₂₉H₃₀N₄O₆
MW: 530.6 g/mol

VQ-021708

Reference Standard

Azilsartan Imidazole Carbonyl Dioxolene Ester

Azilsartan Imidazole Carbonyl Dioxolene Ester

CAS: 1514933-19-7
Formula: C₃₃H₂₈N₆O₈
MW: 636.6 g/mol

VQ-029335

Reference Standard

Azilsartan Impurity 1 chemical structure

Azilsartan Impurity 1

CAS: 139481-44-0
Formula: C₂₅H₂₁N₃O₃
MW: 411.5 g/mol

VQ-004468

Reference Standard

Azilsartan Impurity 1 chemical structure

Azilsartan Impurity 1

CAS: 1348337-81-4
Formula: C₂₄H₁₈N₄O₄
MW: 426.4 g/mol

VQ-047519

Reference Standard

Azilsartan Impurity 16 chemical structure

Azilsartan Impurity 16

CAS: 1027181-25-4
Formula: C₂₅H₂₂N₄O₅
MW: 458.5 g/mol

VQ-044331

Reference Standard

Azilsartan Impurity 35 chemical structure

Azilsartan Impurity 35

CAS: 161862-32-4
Formula: C₁₅H₁₁BrN₂O₂
MW: 331.16 g/mol

VQ-047516

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