2-Ethoxythiazole (CAS 15679-19-3) — Top Note Fragrance Ingredient
2-Ethoxythiazole
CAS 15679-19-3
What Is 2-Ethoxythiazole?
2-Ethoxythiazole (CAS 15679-19-3) is an aroma chemical used as a fragrance and flavour ingredient. Its odour is described as bakery, sweet and fruit, placing it within the gourmand family as a top note with high volatility. With a molecular weight of 129.2 (formula C5H7NOS), it is handled by perfumers as a building block for compositions where a bakery character is desired. The data below is compiled from public chemical and regulatory sources.
Safety Profile
HANDLE WITH CARE
What Does 2-Ethoxythiazole Smell Like?
The odour profile of 2-Ethoxythiazole is reported as bakery, sweet, fruit, fish, garlic, spices, cold, sour, burnt, acid, warm, musky, sweaty, ammonia/urinous, decayed, grass, flower, chemical, edible. The dominant facet is its bakery character, with the remaining notes adding nuance and complexity. As a top note it contributes to the opening of a fragrance. Perceived intensity and exact character depend on concentration, the carrier and the surrounding accord.
Scent Profile
Profile derived from public odour-descriptor data; relative, not absolute.
Chemistry & Properties
The Chemistry
2-Ethoxythiazole has the molecular formula C5H7NOS and a molecular weight of 129.2 g/mol. Its canonical SMILES representation is CCOC1=NC=CS1. Its reported log P (XLogP) of 1.54 indicates a moderately polar molecule, which informs how it partitions in a formula. Physical constants below are drawn from PubChem and EPA CompTox public datasets.
Physical & Chemical Properties
| Molecular Weight | 129.2 g/mol |
|---|---|
| Boiling Point | 167.9 °C |
| Melting Point | 3.15 °C |
| Flash Point | 58.32 °C |
| Density | 1.13 g/cm³ |
| Vapor Pressure | 1.51 mmHg |
| Water Solubility | 0.03909 g/L |
| XLogP | 1.54 |
Perfumer Guide
Alternatives & Comparisons
Ingredients occupying a similar odour space — useful as substitutes or companions when 2-Ethoxythiazole is unavailable or restricted.
Shares bakery, sweet, fruit character — a candidate substitute or companion in the same odour space.
Shares bakery, sweet, fruit character — a candidate substitute or companion in the same odour space.
Shares acid, ammonia/urinous, bakery character — a candidate substitute or companion in the same odour space.
Safety & Regulatory
⚠ Regulatory Disclaimer
General reference only. IFRA, REACH and EU Cosmetics Regulation standards update periodically. Consult the current IFRA Standards Library before formulating. Not legal or regulatory advice.
IFRA Status
No IFRA restriction recorded in the data set. This is not a guarantee of unrestricted status — always confirm against the current IFRA Standards Library.
GHS Classification
Signal word: Warning
Open 2-Ethoxythiazole in Fragrance Studio (Pro) for the calibrated vapour-pressure curve, the modelled odour-threshold estimate, and the substitute-matching engine across 2,900+ aromachemicals.
References & Sources
- PubChem Compound Summary (NIH) — search by InChIKey
- EPA CompTox Chemicals Dashboard — physicochemical & fate data
- IFRA Standards Library (49th / 51st Amendment)
Data: PubChem (NIH), EPA CompTox, IFRA. Last reviewed: Jun 2026.
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