In short
Cyclotene (methyl cyclopentenolone) has a sweet maple-caramel note reminiscent of maple syrup and fenugreek.
What Cyclotene smells like
Cyclotene (methyl cyclopentenolone, maple lactone) is a maple-caramel material — more specifically maple than most molecules, in one glossary's description, with a fenugreek-like warmth. Suppliers report nutty, walnut-like undertones with hints of celery and tobacco, and a maple-liquorice odour when diluted. It is one of the key aroma compounds of maple syrup and occurs in roasted coffee and fenugreek. It is overwhelming at strength and used at trace levels.
- Leading note
- Maple caramel
- Supporting facets
- Nutty, walnut
- Faint facets
- Liquorice, celery, tobacco
- Character
- Sweet, warm, potent
What makes Cyclotene distinctive
The maple note itself, without fenugreek's curry: caramel with walnut and a breath of liquorice.
Concentration and dilution
Overwhelming at high concentration; a maple-liquorice note on dilution.
How Cyclotene is used
Used at trace levels in gourmand, tobacco, fougère and chypre compositions, where it can partly replace coumarin, and in maple and caramel flavours.
Typical role: modifier (used in small amounts to change the character of a blend).
How Cyclotene differs from similar materials
- Sotolone
- Sotolone is maple only at extreme dilution and fenugreek-curry above it; cyclotene is a steadier maple-caramel.
- Maltol
- Maltol is toasted caramel and bread crust; cyclotene is more specifically maple, with a nutty side.
- Ethyl Maltol
- Ethyl maltol is sugary candyfloss; cyclotene is maple and nutty caramel.
- Fenugreek Absolute
- Fenugreek absolute is savoury, with curry and celery; cyclotene is a clean maple-caramel.
- Ethyl Cyclopentenolone
- Ethyl cyclopentenolone, the ethyl homologue, is darker and more layered, with roast and rum beside the maple.
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
A solid; dissolve before use.
Identity and classification
- Type
- Aroma chemical
- Origin
- Occurs in nature
- Odour family
- Gourmand / Woody
- Note position
- Heart note
- Physical form at room temperature
- Solid
- Also known as
- Methyl cyclopentenolone
- CAS number
- 80-71-7
- Molecular formula
- C6H8O2
- Molecular weight
- 112.13 g/mol
- IUPAC name
- 2-hydroxy-3-methylcyclopent-2-en-1-one
The CAS number, formula and molecular weight are taken from PubChem compound 6660, whose own record lists this CAS number; checked 19 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 report it as not meeting the GHS hazard criteria (1,571 of 1,763 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
-
Ethyl Maltol
Aroma chemical · Gourmand / Fruity — candyfloss, caramel, sweet, jammy
-
Vanillin
Aroma chemical · Gourmand / Amber — vanilla, sweet, creamy
-
Coumarin
Aroma chemical · Powdery / Fougère — hay, sweet, almond, tobacco
Cyclotene is also suggested as a partner on the pages for Ethyl Cyclopentenolone and Homofuraneol.
Used in formulas and accords
Used in 7 published formulas
Cyclotene is an ingredient in 5 perfume formulas and 2 accords in the Formula & Accord Library.
Community formulas
RUŌOD House Originals
Original compositions by RUŌOD House.
Further reading
Questions about Cyclotene
Is Cyclotene natural or synthetic?
The molecule occurs in nature. Commercial Cyclotene 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 Cyclotene?
80-71-7. It was checked against PubChem on 19 October 2026.
Which published formulas use Cyclotene?
Cyclotene is used in 7 published formulas in the RUŌOD Lab Formula & Accord Library, including Cola Amber, Dark Rum Cabinet and Maple Fog. Each is listed with a link under "Used in formulas and accords" on this page.
Sources
- PubChem — compound 6660, checked 19 October 2026.
- PubChem — GHS classification (the ECHA C&L Inventory notifications and any harmonised EU entry), read 26 October 2026.
- Premiere Peau — Methyl cyclopentenolone — published perfumery reference.
- Fraterworks — methyl cyclopentenolone — distributor's description.
- ChemicalBook — cyclotene (CAS 80-71-7) — odour database.
- Olfactory profile: the RUŌOD Lab team's synthesis of the published descriptions above, reviewed 24 October 2026. Evidence: more than one published description. Classification and the short description: revision 1. Descriptions of odour are judgement, not measurement.