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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

1,516in stock

COA + SDSwith every lot

Reference Standard

Withanolide B chemical structure

CAS: 56973-41-2
Formula: C₂₈H₃₈O₅
MW: 454.6 g/mol

VQ-042969

Reference Standard

Withanoside IV chemical structure

CAS: 362472-81-9
Formula: C₄₀H₆₂O₁₅
MW: 782.9 g/mol

VQ-042968

Reference Standard

Xanomeline N-Methyl Pyridimium Impurity chemical structure

Xanomeline N-Methyl Pyridimium Impurity

CAS: 2414049-88-8
Formula: C₁₄H₂₀N₃O₂S⁺
MW: 294.39 g/mol

VQ-042974

Reference Standard

Xanthanoic acid chemical structure

Xanthanoic acid

CAS: 82-07-5
Formula: C₁₄H₁₀O₃
MW: 226.23 g/mol

VQ-041717

Reference Standard

Xanthinol Nicotinate chemical structure

Xanthinol Nicotinate

CAS: 437-74-1
Formula: C₁₉H₂₆N₆O₆
MW: 434.4 g/mol

VQ-034712

Reference Standard

Xanthotoxin Impurity A chemical structure

Xanthotoxin Impurity A

CAS: 68123-30-8
Formula: C₁₁H₈O₄
MW: 204.18 g/mol

VQ-042981

Reference Standard

Xylan Sulfate chemical structure

CAS: 37300-21-3
Formula: C₁₀H₁₈O₂₁S₄
MW: 602.5 g/mol

VQ-041398

Reference Standard

Xylometazoline Hydrochloride chemical structure

Xylometazoline Hydrochloride

CAS: 1218-35-5
Formula: C₁₆H₂₅ClN₂
MW: 280.83 g/mol

VQ-024038

Reference Standard

Z-Benfotiamine chemical structure

CAS: 775256-41-2
Formula: C₁₉H₂₃N₄O₆PS
MW: 466.4 g/mol

VQ-034914

Reference Standard

Z-Chlorolefine chemical structure

CAS: 97818-83-2
Formula: C₂₄H₂₃ClO
MW: 362.9 g/mol

VQ-042356

Reference Standard

Z-Norgestimate chemical structure

CAS: 107382-51-4
Formula: C₂₃H₃₁NO₃
MW: 369.5 g/mol

VQ-026959

Reference Standard

Z-O-4-Toluenesulfonyl-L-serine Methyl Ester chemical structure

Z-O-4-Toluenesulfonyl-L-serine Methyl Ester

CAS: 1492-52-0
Formula: C₁₉H₂₁NO₇S
MW: 407.4 g/mol

VQ-039092

Reference Standard

ZAF-2 Impurity 2 (Zafirlukast)

ZAF-2 Impurity 2 (Zafirlukast)

Formula: C₃₃H₃₄N₂O₈
MW: 586.63 g/mol

VQ-006184

Reference Standard

Zafirlukast Impurity D chemical structure

Zafirlukast Impurity D

CAS: 1160235-24-4
Formula: C₄₆H₄₉N₅O₈S
MW: 832 g/mol

VQ-034718

Reference Standard

Zafirlukast Impurity F chemical structure

Zafirlukast Impurity F

CAS: 1160235-28-8
Formula: C₄₉H₄₉N₅O₈S
MW: 868 g/mol

VQ-042987

Reference Standard

Zafirlukast Impurity G chemical structure

Zafirlukast Impurity G

CAS: 1391990-94-5
Formula: C₃₇H₄₈N₄O₅
MW: 628.8 g/mol

VQ-042988

Reference Standard

Zafirlukast Impurity ZAF-1 MCF

Zafirlukast Impurity ZAF-1 MCF

CAS: 1159195-72-8
Formula: C₂₁H₂₂N₂O₅
MW: 382.41 g/mol

In stock

Reference Standard

Zafirlukast Impurity-2

Zafirlukast Impurity-2

Formula: C₂₄H₂₆N₂O₅
MW: 422.47 g/mol

In stock

Reference Standard

Zafirlukast m-Tolyl Isomer chemical structure

Zafirlukast m-Tolyl Isomer

CAS: 1159195-69-3
Formula: C₃₁H₃₃N₃O₆S
MW: 575.7 g/mol

VQ-034720

Reference Standard

Zafirlukast MAM Impurity-1

Zafirlukast MAM Impurity-1

Formula: C₂₈H₂₈N₄O₃
MW: 468.55 g/mol

In stock

Reference Standard

Zafirlukast MAM Impurity-2

Zafirlukast MAM Impurity-2

Formula: C₂₉H₃₀N₂O₆
MW: 502.56 g/mol

VQ-006188

Reference Standard

Zafirlukast p-Tolyl Isomer chemical structure

Zafirlukast p-Tolyl Isomer

CAS: 1159195-70-6
Formula: C₃₁H₃₃N₃O₆S
MW: 575.7 g/mol

In stock

Reference Standard

Zafirlukast ZAF-1 Impurity 1

Zafirlukast ZAF-1 Impurity 1

Formula: C₄₀H₄₄N₄O₇
MW: 692.8 g/mol

In stock

Reference Standard

Zafirlukast ZAF-3 Impurity-1

Zafirlukast ZAF-3 Impurity-1

Formula: C₃₉H₄₂N₄O₇.C₇H₉NO₂S
MW: 849.99 g/mol

VQ-006191

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