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Molekula

Molekula

Maleimide

SKU 64677156 CAS 541-59-3 C4H3NO2 MW 97.07 In stock Bulk quantities on request

Supplying 4,500+ customers in over 80 countries

ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 1999 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need

Maleimide is an organic compound with a reactive imide functional group, widely used in bioconjugation, polymer synthesis, and peptide chemistry as a monofunctional thiol-reactive reagent for alkylating and blocking cysteine thiol groups in proteins, peptides, and other biomolecules. Its high reactivity makes it essential in creating stable bioconjugates for research, diagnostics, and therapeutic applications. This chemical has a CAS number of 541-59-3, a molecular formula of C4H3NO2, and a molecular weight of 97.07 g/mol. It is stored at ambient conditions but requires careful handling due to its Danger classification.

Molekula supplies Maleimide at ≥99.0% purity (HPLC) in 25 g packs, from £106.44 inc. VAT. It is in stock for same-day dispatch. Every batch ships with a certificate of analysis, and safety data sheets are available in 6 languages. Larger quantities, up to multi-tonne, are quoted on request.

Expect a response within hours Speak to a chemist: +44 (0) 3302 000333

Example image for illustration only. Other packaging and pack sizes are available.

Pricing & pack sizes

Pack sizes & pricing

In stock — same-day dispatch

These pack sizes aren't a limit. Molekula manufactures, sources and repacks to order — if you need 500 kg and only see 1 kg listed, . We quote from grams to multi-tonne.

Need a different size? Add the nearest pack and change the size in your basket — we price it at the same rate per unit.

  • 25 g — £88.70 per pack ex VAT · £106.44 inc. VAT

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Prices exclude VAT/sales tax and shipping.

Specifications

Property Value
Appearance White or off-white powder
Purity (HPLC) ≥99.0%
Water (KF) ≤0.5%

Storage & handling

Property Value
Storage Temperature Ambient
Transport Class 8 (6.1)
Packing Group II
Acidity Neutral

Literature values

Published physical properties of the substance, not batch specifications.

Property Value
Vapour Pressure 0.00000277 mmHg

Source: PubChem CID 10935 (Haz-Map)

Identification

Property Value
SKU 64677156
CAS Number 541-59-3
IUPAC Name pyrrole-2,5-dione
EC Number 208-787-4
Molecular Formula C4H3NO2
Molecular Weight 97.07
Exact Mass 97.0164
SMILES C1=CC(=O)NC1=O
InChIKey PEEHTFAAVSWFBL-UHFFFAOYSA-N
InChI InChI=1S/C4H3NO2/c6-3-1-2-4(7)5-3/h1-2H,(H,5,6,7)
PubChem CID 10935
UN Number UN2923
REACH Code Y110
TSCA Listed Yes
HTS Code 2925.19.9100
Tariff Code 2925199590

Safety & GHS

Danger
  • GHS pictogram — Corrosive Corrosive GHS05
  • GHS pictogram — Toxic Toxic GHS06
  • GHS pictogram — Health Hazard Health Hazard GHS07
  • GHS pictogram — Serious Health Hazard Serious Health Hazard GHS08

Hazard statements

  • H301 Toxic if swallowed
  • H314 (sub cat. 1B) Causes severe skin burns and eye damage
  • H317 May cause an allergic skin reaction
  • H340 May cause genetic defects

Precautionary statements

  • P260 Do not breathe dust/fume/gas/mist/vapours/spray
  • P280 Wear protective gloves/protective clothing/eye protection/face protection
  • P301+310 IF SWALLOWED: Immediately call a POISON CENTER or doctor/physician
  • P303+361 IF ON SKIN (or hair): Remove immediately all contaminated clothing. Rinse with water/shower
  • P304+312 IF INHALED: Call a POISON CENTER or doctor/physician if you feel unwell
  • P305+351+338 IF IN EYES: Rinse with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing

Documents

Certificate of Analysis (CoA) by batch

Enter a lot or batch number to retrieve the CoA for that specific batch. We can generate one from spec data if no PDF is on file.

Quality certificates

Molekula Group is certified to ISO 9001:2015 (quality) and ISO 14001:2015 (environmental management), audited by a UKAS-accredited body. Both certificates are valid to 17 May 2028.

Synonyms

  • 1H-Pyrrole-2,5-dione
  • 2,5-dihydro-1H-pyrrole-2,5-dione
  • 2,5-Dioxo-2,5-dihydropyrrole; 3-Pyrroline-2,5-dione; Maleic Imide; NSC 13684;
  • 2,5-Pyrroledione
  • 3-Pyrroline-2,5-dione
  • 5-hydroxy-2H-pyrrol-2-one
  • maleic acid imide
  • Maleic imide
  • Maleinimide
  • Pyrrole-2,5-dione

Frequently asked questions

What is maleimide primarily used for?

Maleimide is commonly used in bioconjugation (e.g., protein labeling), polymer chemistry, and as a thiol-alkylating or thiol-blocking reagent in biochemical research.

What is the chemical formula and molecular weight of maleimide?

The chemical formula is C₄H₃NO₂, and the molecular weight is 97.07 g/mol.

What is the recommended storage condition for maleimide?

Store maleimide at ambient temperature in a dry, well-ventilated area, away from direct sunlight.

What grades of maleimide does Molekula supply?

We supply maleimide as a white or off-white powder with a purity of ≥99.0% (HPLC) and a water content of ≤0.5% (KF), suitable for research and development applications.

Can Molekula supply maleimide in bulk quantities?

Yes, we offer bulk quantities of maleimide—please contact our sales team for pricing and availability.

What documentation comes with a maleimide order?

Each order includes a Certificate of Analysis (CoA), Material Safety Data Sheet (MSDS), and batch-specific documentation for traceability.

Where can I buy Maleimide?

Directly from Molekula, which lists Maleimide in 25 g packs from £106.44 inc. VAT, with a certificate of analysis for every batch. Larger quantities are quoted on request. Molekula's offices: United Kingdom, France, Spain, Germany, Italy, United States and China.

Is Maleimide dangerous goods for shipping?

Yes. Maleimide ships as dangerous goods: UN2923, class 8 (6.1), packing group II.

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