In short
Musk R1 is Givaudan's 11-oxahexadecanolide, a macrocyclic musk with a creamy, powdery character. Its 1962 discoverers found it equal in character and intensity to pentadecanolide.
What Musk R1 smells like
Givaudan describes Musk R1 as a sensual, sophisticated, creamy, powdery macrocyclic musk; Fraterworks adds warm skin-like nuances, clean-laundry freshness and a subtle lactonic sweetness. The 1962 paper in the Journal of the Society of Cosmetic Chemists reported that the 11-oxa isomer was equal in character and odour intensity to pentadecanolide, while the other oxa-isomers were weaker.
- Leading note
- Creamy musk
- Clear facets
- Powdery
- Supporting facets
- Clean
- Faint facets
- Lactonic
- Character
- Soft, tenacious
What makes Musk R1 distinctive
An oxa-lactone musk that matches pentadecanolide in character.
How Musk R1 is used
Used as a soft, creamy macrocyclic musk base and blender: Givaudan calls it sensual, sophisticated, creamy and powdery, and Fraterworks finds warm skin-like and clean-laundry nuances, so it serves in skin musks, white florals and powdery compositions as well as functional products.
Typical role: fixative (slow to evaporate; helps a blend last and holds lighter notes); blender (smooths the joins between other materials).
How Musk R1 differs from similar materials
- Exaltolide
- The 1962 paper on the oxa-lactones found 11-oxahexadecanolide equal in character and intensity to pentadecanolide (Exaltolide); Givaudan describes it as creamy and powdery. (compared directly by a cited source)
An asterisk marks a difference that a cited source states directly. The others compare the published descriptions of each material. Smell varies with grade, supplier and dilution; compare them side by side on blotters before substituting one for another.
Identity and classification
- Type
- Aroma chemical
- Origin
- Synthetic
- Odour family
- Musky / Powdery
- Note position
- Base note
- Physical form at room temperature
- Liquid
- Also known as
- 11-Oxahexadecanolide, 1,7-Dioxacycloheptadecan-8-one
- CAS number
- 3391-83-1
- Molecular formula
- C15H28O3
- Molecular weight
- 256.38 g/mol
- IUPAC name
- 1,7-dioxacycloheptadecan-8-one
The CAS number, formula and molecular weight are taken from PubChem compound 18826, 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 report it as not meeting the GHS hazard criteria (1,541 of 1,557 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
-
Exaltolide
Aroma chemical · Musky / Powdery — musky, soft, powdery, animalic
-
Habanolide
Aroma chemical · Musky / Metallic — musky, clean, metallic, powdery
-
Ethylene Brassylate
Aroma chemical · Musky / Powdery — musky, powdery, sweet, soft
Used in formulas and accords
Used in 23 published formulas
Musk R1 is an ingredient in 22 perfume formulas and 1 accord in the Formula & Accord Library.
Community formulas
RUŌOD House Originals
Original compositions by RUŌOD House.
Further reading
Questions about Musk R1
Is Musk R1 natural or synthetic?
Musk R1 is synthetic — it is made by chemical synthesis.
What is the CAS number of Musk R1?
3391-83-1. It was checked against PubChem on 24 October 2026.
Which published formulas use Musk R1?
Musk R1 is used in 23 published formulas in the RUŌOD Lab Formula & Accord Library, including Ambrette Halo, Apricot Dust and Birch Ghost. Each is listed with a link under "Used in formulas and accords" on this page.
Sources
- PubChem — compound 18826, checked 24 October 2026.
- PubChem — GHS classification (the ECHA C&L Inventory notifications and any harmonised EU entry), read 26 October 2026.
- Fraterworks — Musk R1 — distributor's description.
- The Good Scents Company — 11-oxahexadecanolide — odour database.
- Journal of the Society of Cosmetic Chemists 14(1), 1962 — macrocyclic oxa-lactones — published literature.
- Olfactory profile: the RUŌOD Lab team's synthesis of the published descriptions above, reviewed 26 October 2026. Evidence: more than one published description. Classification and the short description: revision 1. Descriptions of odour are judgement, not measurement.