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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

Tobramycin Carbamate chemical structure

Tobramycin Carbamate

CAS: 51736-77-7
Formula: C₁₉H₃₈N₆O₁₀
MW: 510.5 g/mol

VQ-035529

Reference Standard

Tofacitinib Amine Impurity chemical structure

Tofacitinib Amine Impurity

CAS: 477600-74-1
Formula: C₁₃H₁₉N₅
MW: 245.32 g/mol

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Reference Standard

Tofacitinib Benzyl Impurity chemical structure

Tofacitinib Benzyl Impurity

CAS: 477600-73-0
Formula: C₂₀H₂₅N₅
MW: 335.4 g/mol

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Reference Standard

Tofacitinib Butyl Impurity chemical structure

Tofacitinib Butyl Impurity

CAS: 2716897-36-6
Formula: C₂₃H₃₁N₇O₃
MW: 453.5 g/mol

VQ-042585

Reference Standard

Tofacitinib Diastereomer chemical structure

Tofacitinib Diastereomer

CAS: 344418-92-4
Formula: C₁₆H₂₀N₆O
MW: 312.37 g/mol

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Reference Standard

Tofacitinib Diastereomer-1 and 2 chemical structure

Tofacitinib Diastereomer-1 and 2

CAS: 2734856-31-4
Formula: C₁₆H₂₀N₆O
MW: 312.37 g/mol

VQ-034310

Reference Standard

Tofacitinib Impurity 24 chemical structure

Tofacitinib Impurity 24

CAS: 134965-85-8
Formula: C₁₂H₇ClN₆
MW: 270.68 g/mol

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Reference Standard

Tofacitinib Impurity 9 chemical structure

Tofacitinib Impurity 9

CAS: 2382711-65-9
Formula: C₃₂H₄₀N₁₂O₂
MW: 624.7 g/mol

VQ-042581

Reference Standard

Tofacitinib Impurity E chemical structure

Tofacitinib Impurity E

CAS: 477600-70-7
Formula: C₁₄H₂₂N₂
MW: 218.34 g/mol

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Reference Standard

Tofacitinib Impurity F (Hydrochloride) chemical structure

Tofacitinib Impurity F (Hydrochloride)

CAS: 1702274-61-0
Formula: C₂₀H₂₆ClN₅
MW: 371.9 g/mol

VQ-006046

Reference Standard

Tofacitinib Impurity L chemical structure

Tofacitinib Impurity L

CAS: 1675248-19-7
Formula: C₁₆H₂₂N₆O₂
MW: 330.38 g/mol

VQ-023912

Reference Standard

Tofacitinib Impurity N (Freebase) chemical structure

Tofacitinib Impurity N (Freebase)

CAS: 1260614-73-0
Formula: C₁₃H₁₉N₅
MW: 245.32 g/mol

VQ-006047

Reference Standard

Tofacitinib Impurity N (TFA Salt) chemical structure

Tofacitinib Impurity N (TFA Salt)

CAS: 1260614-73-0
Formula: C₁₃H₁₉N₅
MW: 245.32 g/mol

VQ-006048

Reference Standard

Tofacitinib Impurity Q chemical structure

Tofacitinib Impurity Q

CAS: 3680-69-1
Formula: C₆H₄ClN₃
MW: 153.57 g/mol

VQ-006049

Reference Standard

Tofacitinib Impurity R chemical structure

Tofacitinib Impurity R

CAS: 479633-63-1
Formula: C₁₃H₁₀ClN₃O₂S
MW: 307.76 g/mol

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Reference Standard

Tofacitinib impurity Z chemical structure

Tofacitinib impurity Z

CAS: 477600-76-3
Formula: C₁₅H₂₁N₅O
MW: 287.36 g/mol

VQ-043536

Reference Standard

Tofacitinib N-hydroxy impurity chemical structure

Tofacitinib N-hydroxy impurity

CAS: 2459302-76-0
Formula: C₁₃H₁₉N₅O
MW: 261.32 g/mol

VQ-043333

Reference Standard

Tofacitinib Related Compound 2 Hydrochloride chemical structure

Tofacitinib Related Compound 2 Hydrochloride

CAS: 1640971-87-4
Formula: C₁₀H₁₈ClN₃O
MW: 231.72 g/mol

VQ-042579

Reference Standard

Tofacitinib Related Compound 23 DiHCl chemical structure

Tofacitinib Related Compound 23 DiHCl

CAS: 2640342-78-3
Formula: C₁₃H₂₃Cl₂N₅
MW: 320.3 g/mol

VQ-034311

Reference Standard

Tofacitinib Trichloro Dimer Impurity chemical structure

Tofacitinib Trichloro Dimer Impurity

CAS: 2504210-45-9
Formula: C₁₂H₅Cl₃N₆
MW: 339.6 g/mol

VQ-042588

Reference Standard

Tofisopam Impurity 4 chemical structure

Tofisopam Impurity 4

CAS: 4483-47-0
Formula: C₂₂H₂₈O₄
MW: 356.5 g/mol

VQ-034314

Reference Standard

Tolmetin 3-Isomer

Tolmetin 3-Isomer

CAS: 2514774-66-2
Formula: C₁₅H₁₄NNaO₃
MW: 279.27 g/mol

VQ-034324

Reference Standard

Tolmetin Impurity 6 chemical structure

Tolmetin Impurity 6

CAS: 33369-52-7
Formula: C₁₆H₁₇NO₃
MW: 271.31 g/mol

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Reference Standard

Tolnaftate Impurity A chemical structure

Tolnaftate Impurity A

CAS: 135-19-3
Formula: C₁₀H₈O
MW: 144.17 g/mol

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