Ambrettolide – the Macrocyclic Ambrette Musk
Ambrettolide by Givaudan – The Complete Reference
There are musk materials that are loud. And there is Ambrettolide – one of the most refined materials in perfumery, named after a plant related to okra, and discovered by a chemist whose name hardly anyone knows, even though his discoveries still shape perfumery today.
This page explains where Ambrettolide comes from, why the chemistry behind it is more complicated than it seems – and why Givaudan developed a completely new manufacturing method for it.
Contents
- The origin – one plant, a warning shot, 60 tonnes
- 1927 – the discovery by an almost forgotten chemist
- Two isomers, one problem – the shellac dependency
- Givaudan's answer – metathesis instead of shellac
- What does Ambrettolide smell like?
- Macrocyclic musk – why the molecule class matters
- Dosage and application
- Practical – combining and storing
- IFRA status and regulation
- Frequently asked questions
1. The origin – one plant, a warning shot, 60 tonnes
Ambrettolide takes its name from ambrette – the seeds of Abelmoschus moschatus, a tropical hibiscus species closely related to okra. In India the plant is called Mushkdana or Kasturi Bhendi, which roughly means musk okra.
The harvest is both laborious and peculiar. The plant is grown in tropical regions of India, Madagascar, Ecuador and other countries. During the harvest season from late May to August, fields have to be defended against parrots that love the seeds – with blank-firing scare guns. After harvest, the seeds are stored at altitudes of around 3,000 meters to protect them from parasites.
The result of this effort: around 60 tonnes of ambrette seeds per year worldwide – a vanishingly small quantity for a global perfumery industry. An essential oil is obtained from the seeds whose characteristic musk scent comes to a considerable extent from a single group of substances: macrocyclic lactones, foremost among them Ambrettolide.
Sylvaine Delacourte, former perfumer at Guerlain, describes the fascination this way: ambrette is the champagne among aroma materials – a base note so alive that you can sense its scent already in the top note.
2. 1927 – the discovery by an almost forgotten chemist
In 1927, the German chemist Max Kerschbaum isolated a compound with an extraordinary musk character from ambrette seeds. He called it Ambrettolide.
Kerschbaum's name is barely known today – yet with this one discovery he laid the foundation for an entire class of materials. In the same year he isolated a related compound from angelica root oil: Exaltolide (pentadecalactone), still one of the most important musk materials in perfumery. Two discoveries, one year, one chemist – and the beginning of macrocyclic musk chemistry as we know it today.
In the following decades, Firmenich and IFF developed their own synthesis processes. In the early 1970s, IFF secured key patents (US Patent 3,681,395) that established production methods still in use today.
3. Two isomers, one problem – the shellac dependency
What is often simplified in textbooks is in reality more complicated: there is not just one Ambrettolide, but two structurally different isomers, each with its own designation.
7-Ambrettolide is the compound that occurs naturally in ambrette seed oil – exactly the one Kerschbaum isolated in 1927. 9-Ambrettolide is a related structural isomer with the double bond in a different position, likewise prized as a valuable perfumery raw material. The commercially widespread material is often loosely called Ambrettolide, but is more precisely designated iso-Ambrettolide.
Here it gets interesting: 9-Ambrettolide is produced industrially from aleuritic acid – and aleuritic acid in turn is traditionally obtained from shellac. Shellac is a resin secreted by the lac insect on trees in India and Thailand. The availability and quality of this natural raw material depend on climatic conditions and socioeconomic factors – a dependency that raises growing concerns about supply chains and price stability.
Additionally complicated: in natural ambrette seed oil, Ambrettolide does not occur in isolation, but together with structurally very similar lactones – including 14-tetradec-5-enolide and 18-octadec-9-enolide – that are difficult to separate from one another.
4. Givaudan's answer – metathesis instead of shellac
Givaudan researchers led by the chemist Andreas Goeke developed an alternative synthesis route that bypasses the dependency on shellac: a molybdenum-catalyzed cross-metathesis that produces Ambrettolide under largely solvent-free conditions.
The process starts with renewable octenyl decanoate, which is carefully freed of traces of water, oxygen and peroxides. Through a controlled polymerization and a subsequent step of intramolecular transesterification-depolymerization, a new quality of Ambrettolide is created with an E/Z isomer ratio of 85:15 – marketed under the name AmbreXolide.
This development is part of Givaudan's FiveCarbon Path – a strategy focused on renewable carbon, efficiency in synthesis and biodegradable aroma molecules, while at the same time using carbon from waste and side streams.
Ambrettolide thus joins a series of biotechnologically produced Givaudan materials – including Ambrofix™, whose production from sugarcane requires around 100 times less land area than traditional processes, according to Givaudan.
5. What does Ambrettolide smell like?
Givaudan describes the profile with earthy facets, volatile nutty nuances, silky-fruity undertones and liqueur-like accents that develop into a powdery, orris-like floral note. IFF describes a cognac top note over a warm, powdery orris base.
Ambrettolide is perceived as:
- soft musk
- ambrette facets
- subtly fruity nuances (berry, pear)
- silky transparency
- gentle warmth
- fine musk structure
- restrained sensuality
- skin closeness
The odor threshold, according to Givaudan, is 1.97 ng/l – Ambrettolide is thus perceptible even in the finest traces. On the blotter it remains perceptible for one month, according to Givaudan. Characteristically, the material's influence can be felt across practically all evaporation stages of a composition – from the top note to the base note.
6. Macrocyclic musk – why the molecule class matters
Ambrettolide belongs to the class of macrocyclic musk lactones – chemically and ecologically a different family from the better-known polycyclic musk compounds such as Galaxolide or Tonalide.
Polycyclic musk compounds have been criticized for years: studies show persistence in the environment and accumulation in human tissue and aquatic organisms. Macrocyclic musks such as Ambrettolide, by contrast, are considered significantly more readily biodegradable.
According to the Givaudan safety data sheet, Ambrettolide is readily biodegradable – 84% degradation after 28 days (OECD 301F, GLP-tested). It is not classified as a PBT or vPvB substance and contains 100% renewable carbon.
7. Dosage and application
Ambrettolide is frequently used when musk should be perceptible without shifting the fragrance toward a fresh accord or laundry associations. Givaudan officially states the usage range as traces to 2%.
- Traces to 0.1% – supporting effect, barely perceptible on its own, amplifies the radiance of other materials
- 0.1–0.5% – typical usage range in fine fragrance, clear musk presence
- 0.5–2% – a standalone, fruity-musky character emerges
Typical applications are musk accords, skin-scent perfumes, floral compositions, white-flower accords and amber compositions. The raw material is suited to soft base structures, supports the drydown and improves the longevity of a formula – in women's, men's and unisex perfumery as well as in body care, deodorants, shampoo and soaps.
8. Practical – combining and storing
Synergies
- Exaltolide – another Kerschbaum discovery from 1927, classically combines with Ambrettolide into layered, elegant musk bases
- Galaxolide – combines clean white musk with the softer, fruitier depth of Ambrettolide
- Ethylene Brassylate – together with Ambrettolide creates multi-layered, long-lasting musk foundations
- Floral materials such as orris, rose and magnolia – Ambrettolide supports these notes as a texture-giving base note without covering them
Storage
- 10–30°C, dry, protected from light, tightly sealed
- Protect from light – Givaudan explicitly recommends light-protected storage
9. IFRA status and regulation
Ambrettolide (CAS 28645-51-4) is, according to the IFRA 51st Amendment, subject to no quantitative restriction – not even in Category 4 (fine fragrance). It is not classified as a hazardous substance.
In Germany, Ambrettolide is classified as WGK 2 – must not be allowed to enter water bodies or sewers. At the same time it is readily biodegradable (84% after 28 days) and is not listed on the REACH SVHC candidate list.
Check current IFRA standards and EU regulations before use in commercial products.
Frequently asked questions about Ambrettolide
Who discovered Ambrettolide?
The German chemist Max Kerschbaum isolated Ambrettolide from ambrette seeds in 1927. In the same year he also discovered Exaltolide from angelica root oil – two foundations of macrocyclic musk chemistry as it exists today.
Is Ambrettolide the same as the musk from ambrette seeds?
Not exactly. The commercially available material is more precisely designated iso-Ambrettolide. The musk naturally occurring in ambrette seeds carries a different CAS number (7779-50-2) and is occasionally – mistakenly – equated with this material. Both share important olfactory properties but are not identical.
What is AmbreXolide?
AmbreXolide is an Ambrettolide quality developed by Givaudan, produced via a molybdenum-catalyzed metathesis process with a controlled E/Z isomer ratio (85:15) – an alternative to shellac-dependent synthesis routes.
Are there IFRA restrictions for Ambrettolide?
No. Ambrettolide is subject to no quantitative IFRA restriction, not even in fine fragrance.
How does Ambrettolide differ from polycyclic musk compounds?
Ambrettolide belongs to the class of macrocyclic musk lactones and is, according to Givaudan, readily biodegradable (84% after 28 days) – a clear difference from many polycyclic musk compounds, which can persist in the environment.
How long does the scent of Ambrettolide last?
According to Givaudan, one month on the blotter at dosages from traces to 2%.
Why is ambrette seed oil so expensive?
The harvest is extremely laborious: only around 60 tonnes of seeds are produced worldwide per year. The plants have to be protected against bird damage during the harvest season, and the seeds subsequently stored at altitude to avoid parasite infestation.