Impurity reference standards

Tryptophan impurity standards

This page brings together 15 Tryptophan related compounds that analytical teams use to identify, quantify and control impurities in the active ingredient and the finished dosage form. The range includes 6 pharmacopoeial impurities, 1 nitrosamine and 1 metabolite or hydroxylated analogue.

15reference materials

6pharmacopoeial

1nitrosamines

1metabolites

Every standard comes with a certificate of analysis. Structure confirmation data, typically NMR, MS and chromatographic purity, is available on request. They are bought for system suitability, peak identification, quantitation against limits and the impurity justification sections of regulatory submissions. For nitrosamine risk evaluation, the N-nitroso standards allow confirmatory LC-MS testing against the acceptable intake limits.

By impurity type

Pharmacopoeial6EP, USP, BP or JP named impurities

Nitrosamines1N-nitroso impurities for ICH M7 work

Metabolites1Hydroxy, desmethyl and conjugated forms

Counts are based on product names. One compound can fall into more than one type.

All Tryptophan reference materials

1–15 of 15 standards

1-Boc-L-tryptophan

CAS: 146645-63-8
Formula: C₁₆H₂₀N₂O₄
MW: 304.34 g/mol

ZX-035392

1-Nitroso-L-tryptophan

CAS: 68807-89-6
Formula: C₁₁H₁₁N₃O₃
MW: 233.22 g/mol

ZX-027448

4-Benzyloxyindole

CAS: 20289-26-3
Formula: C₁₅H₁₃NO
MW: 223.27 g/mol

ZX-043004

5-Hydroxyindole-3-acetic Acid

CAS: 54-16-0
Formula: C₁₀H₉NO₃
MW: 191.18 g/mol

ZX-033186

L-Tryptophanamide Hydrochloride

CAS: 5022-65-1
Formula: C₁₁H₁₄ClN₃O
MW: 239.7 g/mol

ZX-043448

N-Acetyl-L-Tryptophan

CAS: 1218-34-4
Formula: C₁₃H₁₄N₂O₃
MW: 246.26 g/mol

ZX-027443

N-Carbamyltryptophan

CAS: 54896-75-2
Formula: C₁₂H₁₃N₃O₃
MW: 247.25 g/mol

ZX-031500

Tryptophan - Impurity G

CAS: 21704-80-3
Formula: C₁₁H₁₂N₂O₃
MW: 220.22 g/mol

ZX-027449

Tryptophan Cyclized impurity

CAS: 40856-80-2
Formula: C₁₂H₁₁N₃O₂
MW: 229.23 g/mol

ZX-027447

Tryptophan EP Impurity A

CAS: 132685-02-0
Formula: C₂₄H₂₆N₄O₄
MW: 434.5 g/mol

ZX-027442

Tryptophan EP Impurity C

CAS: 2922-83-0
Formula: C₁₀H₁₂N₂O₃
MW: 208.21 g/mol

ZX-027444

Tryptophan EP Impurity F

CAS: 145545-23-9
Formula: C₉H₁₂N₂O₂
MW: 180.2 g/mol

ZX-027450

Tryptophan EP Impurity H

CAS: 6052-68-2
Formula: C₁₂H₁₂N₂O₂
MW: 216.24 g/mol

ZX-031138

Tryptophan EP Impurity I

CAS: 5470-37-1
Formula: C₁₃H₁₄N₂O₂
MW: 230.26 g/mol

ZX-027445

Tryptophan EP Impurity K

CAS: 149724-31-2
Formula: C₂₀H₁₉N₃O₂
MW: 333.4 g/mol

ZX-027446

Questions

Tryptophan impurities, answered

What Tryptophan reference materials are available?

The catalogue currently lists 15 compounds for Tryptophan, including 6 pharmacopoeial impurities, 1 nitrosamine and 1 metabolite or hydroxylated analogue. Each product page shows the CAS number where one is assigned, the structure, formula and molecular weight.

What documents come with a Tryptophan impurity standard?

A certificate of analysis travels with every lot. On request we share the characterisation set, usually 1H-NMR, mass spectrum, HPLC purity and IR, and for some materials TGA or water content. Ask for the data before ordering if your QA team needs to review it.

Can Zemixal make a Tryptophan impurity that is not listed?

Often yes. Send the structure, name or CAS number with the quantity you need and our sourcing team checks custom synthesis options, usually from 10 mg up to gram scale, with a quoted lead time.

Do you supply Tryptophan nitrosamine impurities?

Yes. 1 N-nitroso compound is listed for Tryptophan. They are used for confirmatory testing and method validation in line with ICH M7 and the nitrosamine guidance from the major regulators.

Nearby APIs in the index

Tryptophol 3 All APIs