Aurelione®

Technical Ingredient Overview

• 🏭 Manufacturer — Symrise

• 🔎 Chemical Name — Cyclohexadec-8(7)-en-1-one

• 🧪 Synonyms — 8-Cyclohexadecen-1-one; (7Z)-Cyclohexadec-7-en-1-one; (8Z)-Cyclohexadec-8-en-1-one

• 📂 CAS — 88642-03-9, 3100-36-5, 2550-59-6

• ⚖️ MW — 236.4 g/mol

• 📝 Odor Type — Musky, Balsamic

• 📈 Odor Strength — High intensity (macrocyclic musk)

• 👃🏼 Odor Profile — Musky, balsamic, powdery, erogenous skin-like effect with animalistic facets

• ⚗️ Uses — Fine fragrance, personal care products, fabric care applications

• 🧴 Appearance — Colorless to pale yellow liquid to solid

What is Aurelione®?

Aurelione® represents a sophisticated synthetic macrocyclic ketone that exemplifies modern fragrance chemistry’s ability to create complex, multifaceted olfactory experiences. This sixteen-carbon cyclic compound with an unsaturated bond belongs to the prestigious family of macrocyclic musks, materials that have revolutionized contemporary perfumery through their unique ability to impart both substantivity and radiance to fragrance compositions.

The molecular structure of Aurelione® features a large ring system characteristic of macrocyclic compounds, specifically containing sixteen carbon atoms arranged in a cyclic formation with a ketone functional group and one double bond. This structural configuration enables the molecule to exist as multiple isomers, each contributing subtle variations to the overall olfactory profile while maintaining the characteristic musky-balsamic signature that defines this ingredient class.

What distinguishes Aurelione® within the macrocyclic ketone family is its remarkable ability to deliver what Symrise describes as an “erogenous, skin-like effect” combined with exceptional radiance throughout fragrance development. This dual character makes it particularly valuable for creating fragrances that achieve both intimate proximity appeal and impressive sillage, a combination that represents one of perfumery’s most challenging technical objectives.

Historical Background

The development of Aurelione® emerged from the broader evolution of macrocyclic musk chemistry that began in earnest during the latter half of the twentieth century. While natural musks had been treasured in perfumery for centuries, their scarcity, cost, and eventual regulatory restrictions drove the fragrance industry toward synthetic alternatives that could deliver comparable olfactory experiences while meeting modern sustainability and ethical standards.

Symrise’s development of Aurelione® represents a significant advancement in this synthetic musk evolution, building upon decades of research into macrocyclic ketone chemistry pioneered by various fragrance houses throughout the 1970s and 1980s. The compound reflects sophisticated understanding of structure-activity relationships in macrocyclic systems, where ring size, functional group positioning, and stereochemistry dramatically influence olfactory character.

The multiple CAS numbers associated with Aurelione® (88642-03-9, 3100-36-5, 2550-59-6) indicate the presence of different isomeric forms, a characteristic feature of macrocyclic ketone production where synthetic processes typically yield mixtures of geometrical and positional isomers. This isomeric complexity, rather than being a limitation, actually contributes to the ingredient’s olfactory richness and natural-seeming character.

Olfactory Profile

Aurelione® exhibits a complex olfactory profile that positions it as a premium macrocyclic musk with distinctive character development throughout its evaporation curve. The primary olfactory impression presents as musky and balsamic, establishing the fundamental musk ketone character that defines this ingredient category. However, Aurelione® transcends simple musk reproduction through its powdery facets, which add sophistication and refinement to the overall impression.

The “erogenous, skin-like effect” that Symrise highlights represents perhaps the most distinctive aspect of Aurelione’s olfactory profile. This characteristic manifests as an intimate, warm quality that seems to merge with natural skin chemistry, creating the impression of enhanced rather than applied fragrance. This skin-compatibility extends beyond simple projection to encompass actual synergy with human pheromonal signatures, a highly prized attribute in contemporary fine fragrance creation.

From a technical perfumery perspective, Aurelione® demonstrates exceptional tenacity characteristics typical of macrocyclic ketones, with persistence extending from hours into days and even months on appropriate substrates. Its high molecular weight (236.4 g/mol) and macrocyclic structure contribute to this remarkable substantivity, while its Log P value of 5.82 indicates significant lipophilic character that enhances skin affinity and longevity.

The radiance that Aurelione® imparts throughout fragrance development represents another crucial technical characteristic. Unlike linear musks that may dominate compositions, Aurelione® functions as an enhancer that amplifies other fragrance components while maintaining its own distinct contribution. This radiating effect proves particularly valuable in complex compositions where multiple olfactory layers must maintain clarity while achieving seamless integration.

Symrise’s technical documentation indicates that synergistic effects occur when combining Aurelione® with other macrocyclic ketones and lactones, suggesting sophisticated blending possibilities for perfumers seeking to create complex musk accords. This compatibility extends the ingredient’s utility beyond simple musk reinforcement into the realm of olfactory architecture, where multiple macrocyclic components work together to create entirely new fragrance experiences.

Industrial & Technical Uses

Aurelione® finds extensive application across multiple fragrance categories, with Symrise providing specific usage recommendations that demonstrate the ingredient’s versatility and technical performance:

• Fine fragrance applications: recommended concentrations range from 1–20%, indicating both the material’s potency and its ability to function effectively across a broad dosage spectrum.

• Eau de Toilette compositions: concentrations up to 4.0%, positioning Aurelione® as a significant structural component rather than merely an auxiliary ingredient.

• Personal care applications:

  • Soap: up to 1.2% at pH 9–10, ensuring excellent alkaline stability.

  • Antiperspirant roll-on: 1.0% in 15% aluminum chlorohydrate at pH 4.

  • Hair care:

    • Shampoo and shower gel: 0.5% at pH 6.

    • Conditioner: 0.4% at pH 4.

• Fabric care:

  • Fabric softener concentrate: 0.6% at pH 2.5.

  • Heavy-duty liquid detergents: 0.5% at pH 8.5.

These applications particularly benefit from Aurelione®’s skin-like character, tenacity, and radiance, demonstrating robustness and practical utility even under challenging formulation conditions.

Regulatory & Safety Overview

The regulatory status of Aurelione® reflects comprehensive safety assessment protocols applied to modern macrocyclic ketones:

• Evaluated by the Research Institute for Fragrance Materials (RIFM), providing scientific foundation for global regulatory acceptance (Api et al., 2011).

• Subject to IFRA restrictions as part of the broader macrocyclic ketone category; maximum concentration potentially set at 4.3% (recent IFRA amendments).

• Multiple CAS numbers (88642-03-9, 3100-36-5, 2550-59-6) indicate different geometric or positional isomers, requiring careful regulatory tracking.

• Readily biodegradable: 80%, meeting international environmental safety standards.

• EU-REACH registration number: 01-0000018950-67, confirming compliance with European chemical registration requirements.

• Low acute toxicity and no significant repeat dose toxicity in comprehensive RIFM studies; observed effects reversible after cessation of exposure.

• GC purity specification: minimum 93% (sum of isomers) for consistent quality.

• Flash point exceeds 100°C, suitable for industrial handling and storage.

References

• Api, A. M., Bartok, J., Bruze, M., Fragrance Expert Panel, Givaudan, & Research Institute for Fragrance Materials. (2011). A toxicological and dermatological assessment of macrocyclic ketones when used as fragrance ingredients: The RIFM Expert Panel. Food and Chemical Toxicology, 49(12), 3197-3206.

• Symrise AG. (2023). Aurelione® - Technical Data Sheet. Retrieved from https://www.symrise.com/fileadmin/symrise/Marketing/Scent_and_care/Aroma_molecules/Ingredient_finder/SYM_PC_Datenblaetter/SYM_PC-Aurelione.pdf