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Impurities & Reference Standards

API Impurities

Source 1942 api impurities for research, QC and production, documented with COA and SDS.

14,098products

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COA + SDSwith every lot

Reference Standard

Remdesivir O-Desphosphate Analogue chemical structure

Remdesivir O-Desphosphate Analogue

CAS: 1191237-69-0
Formula: C₁₂H₁₃N₅O₄
MW: 291.26 g/mol

In stock

Reference Standard

Remdesivir O-Desphosphate Tri-OBn Impurity chemical structure

Remdesivir O-Desphosphate Tri-OBn Impurity

CAS: 1355049-94-3
Formula: C₃₂H₃₂N₄O₅
MW: 552.6 g/mol

VQ-035353

Reference Standard

Remdesivir p-NitroPhenoxy L-Alanine Impurity chemical structure

Remdesivir p-NitroPhenoxy L-Alanine Impurity

CAS: 1354823-36-1
Formula: C₂₁H₂₇N₂O₇P
MW: 450.4 g/mol

In stock

Reference Standard

Remdesivir Phosphate Impurity chemical structure

Remdesivir Phosphate Impurity

CAS: 1911578-74-9
Formula: C₁₂H₁₄N₅O₇P
MW: 371.24 g/mol

VQ-033493

Reference Standard

Remimazolam chemical structure

CAS: 1449295-42-4
Formula: C₂₁H₁₉BrN₄O₂
MW: 439.3 g/mol

VQ-048936

Reference Standard

Remimazolam isopropyl ester

Remimazolam isopropyl ester

CAS: 1860899-60-0
Formula: C₂₃H₂₃BrN₄O₂
MW: 467.36 g/mol

VQ-041867

Reference Standard

Remimazolam S-Isomer Acid Impurity chemical structure

Remimazolam S-Isomer Acid Impurity

CAS: 960305-91-3
Formula: C₂₀H₁₇BrN₄O₂
MW: 425.3 g/mol

VQ-033496

Reference Standard

Remogliflozin alpha Isomer chemical structure

Remogliflozin alpha Isomer

CAS: 2170718-60-0
Formula: C₂₃H₃₄N₂O₇
MW: 450.5 g/mol

VQ-041868

Reference Standard

Remogliflozin Etabonate chemical structure

Remogliflozin Etabonate

CAS: 442201-24-3
Formula: C₂₆H₃₈N₂O₉
MW: 522.6 g/mol

VQ-027773

Reference Standard

Repaglinide Impurity 13 chemical structure

Repaglinide Impurity 13

CAS: 765306-65-8
Formula: C₁₆H₂₄N₂O
MW: 260.37 g/mol

VQ-041872

Reference Standard

Repaglinide Impurity 7

Repaglinide Impurity 7

CAS: 1039989-55-3
Formula: C₁₆H₂₆N₂
MW: 246.39 g/mol

VQ-041870

Reference Standard

Resiniferatoxin chemical structure

Resiniferatoxin

CAS: 57444-62-9
Formula: C₃₇H₄₀O₉
MW: 628.7 g/mol

VQ-040636

Reference Standard

Resmetirom Impurity 17 chemical structure

Resmetirom Impurity 17

CAS: 1696366-11-6
Formula: C₇H₉ClN₂O
MW: 172.61 g/mol

In stock

Reference Standard

Resmetirom Impurity 20 chemical structure

Resmetirom Impurity 20

CAS: 107228-52-4
Formula: C₁₀H₁₄Cl₂N₂
MW: 233.13 g/mol

VQ-041877

Reference Standard

Resmetirom Impurity 5 chemical structure

Resmetirom Impurity 5

CAS: 920509-28-0
Formula: C₁₃H₁₃Cl₂N₃O₂
MW: 314.16 g/mol

In stock

Reference Standard

Resmetirom Impurity 6 chemical structure

Resmetirom Impurity 6

CAS: 920509-27-9
Formula: C₁₃H₁₂Cl₃N₃O
MW: 332.6 g/mol

In stock

Reference Standard

Resveratrol Trimethyl Ether chemical structure

Resveratrol Trimethyl Ether

CAS: 22255-22-7
Formula: C₁₇H₁₈O₃
MW: 270.32 g/mol

VQ-041883

Reference Standard

Retigabine Desfluoro RTM-1

Retigabine Desfluoro RTM-1

CAS: 2554150-59-1
Formula: C₁₃H₁₃N₃O₂
MW: 243.26 g/mol

In stock

Reference Standard

Retinoic Acid Related Compound 2

Retinoic Acid Related Compound 2

CAS: 61976-15-6
Formula: C₃₃H₃₉O₄PS
MW: 562.7 g/mol

VQ-037762

Reference Standard

Retinoic acid, (7-cis,13-cis)

Retinoic acid, (7-cis,13-cis)

CAS: 1846574-66-0
Formula: C₂₀H₂₈O₂
MW: 300.44 g/mol

VQ-045029

Reference Standard

Retinoic acid, (7-cis,9-cis,11-cis,13-cis)

Retinoic acid, (7-cis,9-cis,11-cis,13-cis)

CAS: 1846574-68-2
Formula: C₂₀H₂₈O₂
MW: 300.44 g/mol

VQ-045033

Reference Standard

Retinoic acid, (9-cis,11-cis,13-cis) chemical structure

Retinoic acid, (9-cis,11-cis,13-cis)

CAS: 68070-34-8
Formula: C₂₀H₂₈O₂
MW: 300.4 g/mol

VQ-045032

Reference Standard

Revefenacin Ethylamino biphenyl carbamate impurity chemical structure

Revefenacin Ethylamino biphenyl carbamate impurity

CAS: 743460-48-2
Formula: C₂₁H₂₇N₃O₂
MW: 353.5 g/mol

VQ-027785

Reference Standard

Revefenacin Impurity 1 chemical structure

Revefenacin Impurity 1

CAS: 2975124-11-7
Formula: C₂₂H₃₄N₄O₃
MW: 402.5 g/mol

VQ-041888

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