Skip to content

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

Sildenafil Methyl Sulfonate Ester Impurity chemical structure

Sildenafil Methyl Sulfonate Ester Impurity

CAS: 2512206-40-3
Formula: C₁₈H₂₂N₄O₅S
MW: 406.5 g/mol

VQ-028021

Reference Standard

Silodosin (S-ISOMER) chemical structure

Silodosin (S-ISOMER)

CAS: 2182279-45-2
Formula: C₂₅H₃₂F₃N₃O₄
MW: 495.5 g/mol

VQ-021344

Reference Standard

Silodosin carboxylic acid impurity chemical structure

Silodosin carboxylic acid impurity

CAS: 1357252-79-9
Formula: C₂₅H₃₀F₃N₃O₅
MW: 509.5 g/mol

VQ-023756

Reference Standard

Silodosin Dimer Impurity chemical structure

Silodosin Dimer Impurity

CAS: 1453221-45-8
Formula: C₃₅H₄₁F₆N₃O₆
MW: 713.7 g/mol

VQ-023755

Reference Standard

Silodosin Impurity 30

Silodosin Impurity 30

CAS: 2077962-88-8
Formula: C₂₅H₃₂F₃N₃O₅
MW: 511.53 g/mol

VQ-042176

Reference Standard

Silodosin Keto Impurity chemical structure

Silodosin Keto Impurity

CAS: 350797-57-8
Formula: C₂₂H₂₂N₂O₃
MW: 362.4 g/mol

VQ-028028

Reference Standard

Silodosin Nitrile Impurity chemical structure

Silodosin Nitrile Impurity

CAS: 885340-13-6
Formula: C₂₅H₃₀F₃N₃O₃
MW: 477.5 g/mol

VQ-023754

Reference Standard

Silybin B chemical structure

CAS: 142797-34-0
Formula: C₂₅H₂₂O₁₀
MW: 482.4 g/mol

VQ-033855

Reference Standard

Silychristin chemical structure

CAS: 33889-69-9
Formula: C₂₅H₂₂O₁₀
MW: 482.4 g/mol

VQ-033854

Reference Standard

Silydianin chemical structure

CAS: 29782-68-1
Formula: C₂₅H₂₂O₁₀
MW: 482.4 g/mol

VQ-032717

Reference Standard

Simvastatin 6-Oxo Isomer chemical structure

Simvastatin 6-Oxo Isomer

CAS: 130468-11-0
Formula: C₂₅H₃₆O₆
MW: 432.5 g/mol

VQ-033861

Reference Standard

Simvastatin Methyl Ester chemical structure

Simvastatin Methyl Ester

CAS: 145576-26-7
Formula: C₂₆H₄₂O₆
MW: 450.6 g/mol

VQ-028038

Reference Standard

Sinomenine Hydrochloride chemical structure

Sinomenine Hydrochloride

CAS: 6080-33-7
Formula: C₁₉H₂₄ClNO₄
MW: 365.8 g/mol

VQ-042184

Reference Standard

Siponimod 6(III) EZ-Isomer Mixture Impurity

Siponimod 6(III) EZ-Isomer Mixture Impurity

Formula: C₂₅H₃₀F₃NO₂
MW: 433.51 g/mol

In stock

Reference Standard

Siponimod 6(Vi)-E-Isomer Impurity

Siponimod 6(Vi)-E-Isomer Impurity

Formula: C₂₃H₂₅BrF₃NO₂
MW: 484.35 g/mol

In stock

Reference Standard

Siponimod 6(Vi)-EZ-Isomer Mixture Impurity

Siponimod 6(Vi)-EZ-Isomer Mixture Impurity

Formula: C₂₃H₂₅BrF₃NO₂
MW: 484.35 g/mol

In stock

Reference Standard

Siponimod 6(Vi)-Z-Isomer Impurity

Siponimod 6(Vi)-Z-Isomer Impurity

Formula: C₂₃H₂₅BrF₃NO₂
MW: 484.35 g/mol

In stock

Reference Standard

Siponimod 6(VIII)-E-Isomer Impurity

Siponimod 6(VIII)-E-Isomer Impurity

Formula: C₂₃H₂₄Br₂F₃NO
MW: 547.25 g/mol

In stock

Reference Standard

Siponimod 6(VIII)-Z-Isomer Impurity

Siponimod 6(VIII)-Z-Isomer Impurity

Formula: C₂₃H₂₄Br₂F₃NO
MW: 547.25 g/mol

In stock

Reference Standard

Siponimod Acrylic Acid (open ring) Unwanted Impurity

Siponimod Acrylic Acid (open ring) Unwanted Impurity

Formula: C₃₃H₃₉F₃N₂O₅
MW: 600.67 g/mol

In stock

Reference Standard

Siponimod Acrylic Acid Impurity

Siponimod Acrylic Acid Impurity

Formula: C₂₉H₃₅F₃N₂O₃
MW: 516.6 g/mol

In stock

Reference Standard

Siponimod Alcohol Impurity chemical structure

Siponimod Alcohol Impurity

CAS: 1418144-66-7
Formula: C₂₅H₃₀F₃NO₂
MW: 433.5 g/mol

In stock

Reference Standard

Siponimod Aldehyde EZ-Isomer Mixture Impurity

Siponimod Aldehyde EZ-Isomer Mixture Impurity

Formula: C₁₉H₁₈F₃NO₂
MW: 349.35 g/mol

In stock

Reference Standard

Siponimod Aldehyde-E-Isomer Impurity

Siponimod Aldehyde-E-Isomer Impurity

Formula: C₁₉H₁₈F₃NO₂
MW: 349.35 g/mol

In stock

Need a price, a spec or a custom compound?

Send us your list — product names or CAS numbers, grade, quantity and destination. Our team replies with a formal quotation, COA and lead time.

Request a quote Contact sales