moleculefinder

SHEET /m/diacetyl · PubChem CID 650 · CAS 431-03-8 · REV 2026.07

marquee

Diacetyl

from source

C4H6O2 · 86.09 g/mol

Butadione · Dimethyl glyoxal · Acetoacetaldehyde · butanedione

What is Diacetyl?

The taste of butter, made naturally in fermentation. Inhaled as a vapour in flavouring plants it caused the lung disease nicknamed popcorn lung. Found in beer. from source

CategoryFood & flavor
Chemical familyKetones
LeaderboardsBiggestDeadliest

Fig. 1 · 2D structure RDKit

SMILESCC(=O)C(=O)C

Where you'll find it

Beerwhat else is in it →

Curated by MoleculeFinder from source

The dose makes the poison inferred

A reported rat oral LD50 for Diacetyl is 1,580 mg/kg, the dose lethal to half the animals tested. Scaled by body mass alone:

110.6 g
a median lethal dose scaled to 154 lb (110,600 mg)

“The dose makes the poison” is a cross-species estimate shown as neutral science, not a threshold anyone should act on. Real toxicity depends on the person, not body mass alone.

Toxicity & hazards

Toxicity · LD50

1,580 mg/kg · low toxicity · LD50 rat oral from source

The dose lens above scales this to a body weight.

1 more reported value
  • 250 mg/kgLD50 · oral · mouse
DangerFlammableCorrosiveToxicIrritantHealth hazardH225, H302, H315, H317, H318, H331, H332, H335, H351, H370, H372, H373from source

Keep roaming

Where Diacetyl leads

Relatedcomputed
Acetone63% similarBoth carry a ketone group.Pyruvic acid60% similarBoth carry a ketone group.Acetic acid56% similarNo functional group in common: Acetic acid carries a carboxylic acid group, while Diacetyl carries a ketone group.Sodium acetate45% similarCalcium acetate45% similarMethylglyoxal42% similarBoth carry a ketone group.

Sources & methodology

PubChem CID
650
Wikidata
Q408916
Structure
PubChem → RDKit
LD50
PubChem
Similar molecules
MoleculeFinder fingerprint similarity
Everyday relationships
MoleculeFinder editorial curation
Data refreshed

How MoleculeFinder sources and labels its data