In short
4-Methyl-5-vinylthiazole, sold as vinyl sulfurol, is a thiazole flavouring. JECFA describes a nutty, cocoa-like odour.
What 4-Methyl-5-vinylthiazole smells like
JECFA, as published by PubChem, describes 4-methyl-5-vinylthiazole as a colourless liquid with a nutty, cocoa-like odour. PubChem lists vinyl sulfurol among its synonyms and links it to natural-product databases. That is the only published description gathered here.
- Leading note
- Cocoa
- Clear facets
- Nutty
- Character
- Roasted
What makes 4-Methyl-5-vinylthiazole distinctive
Sulfurol's vinyl relative: cocoa and nut rather than meat.
How 4-Methyl-5-vinylthiazole is used
Its documented use is in flavours: JECFA evaluates it as a flavouring agent, and it is reported in cocoa, roasted filberts and other roasted foods. In perfumery it is a trace note for cocoa, nut and roasted effects in gourmand accords.
Typical role: modifier (used in small amounts to change the character of a blend).
How 4-Methyl-5-vinylthiazole differs from similar materials
- Sulfurol
- Sulfurol is beefy and nutty; vinyl sulfurol, its vinyl relative, is described as nutty and cocoa-like.
Each difference compares the published descriptions of the two materials. Smell varies with grade, supplier and dilution; compare them side by side on blotters before substituting one for another.
Formulation considerations
Potent; usually handled diluted.
Identity and classification
- Type
- Aroma chemical
- Origin
- Occurs in nature
- Odour family
- Gourmand
- Note position
- Heart note
- Physical form at room temperature
- Liquid
- Also known as
- Vinyl sulfurol
- CAS number
- 1759-28-0
- Molecular formula
- C6H7NS
- Molecular weight
- 125.19 g/mol
- IUPAC name
- 5-ethenyl-4-methyl-1,3-thiazole
The CAS number, formula and molecular weight are taken from PubChem compound 15654, whose own record lists this CAS number; checked 24 October 2026.
Safety and compliance
Hazard classification of the neat substance, as PubChem summarises it, read 26 October 2026. Companies notifying the ECHA C&L Inventory classify it (1,700 reports): H302 harmful if swallowed (100% of reports). Unless it is harmonised, this is the notifiers' own classification, not a binding one.
This page is general information, not a safety assessment or a specification. Confirm identity, composition, IFRA status and allergen content from your supplier's documents for the lot you hold.
Materials it works with
-
Sulfurol
Aroma chemical · Gourmand — beefy, nutty
-
Cacao Absolute
Absolute · Gourmand — chocolate, cocoa, roasted, bitter
-
2,3,5-Trimethylpyrazine
Aroma chemical · Gourmand — roasted, nutty, cocoa, earthy
Used in formulas and accords
Used in 1 published formula
4-Methyl-5-vinylthiazole is an ingredient in 1 accord in the Formula & Accord Library.
Further reading
Questions about 4-Methyl-5-vinylthiazole
Is 4-Methyl-5-vinylthiazole natural or synthetic?
The molecule occurs in nature. Commercial 4-Methyl-5-vinylthiazole may be made by synthesis or obtained from natural sources, so check the supplier's specification if the distinction matters to you.
What is the CAS number of 4-Methyl-5-vinylthiazole?
1759-28-0. It was checked against PubChem on 24 October 2026.
Which published formulas use 4-Methyl-5-vinylthiazole?
4-Methyl-5-vinylthiazole is used in 1 published formula in the RUŌOD Lab Formula & Accord Library: Chocolate Accord. Each is listed with a link under "Used in formulas and accords" on this page.
Sources
- PubChem — compound 15654, checked 24 October 2026.
- PubChem — GHS classification (the ECHA C&L Inventory notifications and any harmonised EU entry), read 26 October 2026.
- PubChem — 4-Methyl-5-vinylthiazole (CID 15654): JECFA organoleptic description — odour database.
- Olfactory profile: the RUŌOD Lab team's synthesis of the published descriptions above, reviewed 26 October 2026. Evidence: few published descriptions; treat the detail with caution. Classification and the short description: revision 1. Descriptions of odour are judgement, not measurement.