Pyrazine, 2-methoxy-3-(4-methylpentyl)- (CAS 68844-95-1) — Green Top to middle Note Fragrance Ingredient

Green · Woody

Pyrazine, 2-methoxy-3-(4-methylpentyl)-

CAS 68844-95-1

Origin
synthetic
Note
Top to middle
IFRA
Use with awareness
Data as of: Apr 2026

What Is Pyrazine, 2-methoxy-3-(4-methylpentyl)-?

2-methoxy-3-(4-methylpentyl)pyrazine is a synthetic aroma compound that adds a green, bell pepper-like nuance to fragrances. It’s found in high-end perfumes and some gourmand scents. This pyrazine variant matters because it provides a hyper-realistic vegetal note without the volatility of natural sources, allowing perfumers to create crisp, modern green accords that last.

Safety Profile

USE WITH AWARENESS
Generally safeUse with awarenessProfessional use
Safe at IFRA-approved levels
Powerful odorant – use sparingly
CAS
68844-95-1
Formula
Mixture
MW
Variable
Odor Family
Green · Woody
Layer 1 · Enthusiast

What Does Pyrazine, 2-methoxy-3-(4-methylpentyl)- Smell Like?

A razor-sharp green burst reminiscent of freshly cut bell peppers, with an underlying earthy complexity. The initial pungency mellows into a sophisticated vegetal heart, like sun-warmed tomato leaves. Over time, it develops a subtle nutty undertone, creating an unusual bridge between green and gourmand notes. Exceptionally tenacious for a pyrazine, it maintains its character through drydown.

Scent Profile

In Famous Fragrances

Fragrance associations may not reflect actual formulations.

Green Irish Tweed(Creed, 1985)

Used to amplify the naturalistic green facets, creating the illusion of dew-covered clover leaves without overwhelming the floral heart.

Vent Vert(Balmain, 1947)

Modern reformulations employ this pyrazine to achieve the legendary galbanum effect with greater stability and diffusion.

Layer 2

2D Molecular Structure

Pyrazine, 2-methoxy-3-(4-methylpentyl)-

SMILES: COC1=NC=CN=C1CCCC(C)C

Chemistry, Properties & Perfumer Guide

The Chemistry

A methoxy-substituted alkylpyrazine belonging to the heterocyclic organic compounds class. Pyrazines are formed via Maillard reactions in nature but synthesized for perfumery through controlled condensation reactions. The 4-methylpentyl side chain increases substantivity compared to simpler pyrazines, while the methoxy group modulates intensity.

Physical & Chemical Properties

AppearanceColorless to pale yellow liquid
Boiling PointEstimated 250-270°C
Density~0.95 g/cm³ (estimated)

Perfumer Guide

Note Position
Top to middle
Volatility
Medium (2-4 hours)
Blending
Challenging but rewarding
ApplicationTypical %RangeNotes
Fine Fragrance0.01-0.1%Up to 0.3%Powerful modifier – use trace amounts
Functional Fragrance0.001-0.01%Up to 0.05%For green fabric conditioner notes

Classic Accords

Tip: Always pre-dilute to 1% or lower before incorporating into blends.

Alternatives & Comparisons

1
2-Isobutyl-3-methoxypyrazine CAS 24683-00-9

More intense bell pepper character but higher volatility. Used when extreme top note impact is desired.

2
2-Ethyl-3,5(6)-dimethylpyrazine CAS 27043-05-6

For warmer, nuttier green effects with less vegetal sharpness.

Layer 3

Safety, Regulatory & Sustainability

⚠ Regulatory Disclaimer

General reference only. Consult current IFRA Standards Library before formulating.

IFRA Status

No specific restrictions under IFRA 49th Amendment. General pyrazine guidelines apply.

RIFM Assessment

RIFM has evaluated related pyrazines but no specific assessment found for this derivative.

Sustainability

Synthetic production avoids agricultural land use. The multi-step synthesis requires careful solvent management. No known ecological toxicity at usage levels.

Explore Pyrazine, 2-methoxy-3-(4-methylpentyl)-

Browse essential oils and aroma compounds.

Browse on iHerb →

Affiliate disclosure: we may earn a small commission at no extra cost to you.

References

  1. PubChem Compound Summary Pyrazine derivatives
  2. Leffingwell & Associates (2015). Pyrazines in Perfumery.

Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.

Report a data error

Ingredient Data Sheet

CAS 68844-95-1

Physical Properties

Molecular Weight194.27 g/mol🔬 PubChem
LogP (Octanol-Water)3.5🔬 PubChem
Boiling Point262 °C🔬 EPA CompTox
Vapor Pressure0.0295 mmHg @ 25°C📊 OPERA
Flash Point83.9 °C🔬 EPA CompTox
Involatility Index0.0023💻 Calculated
log Kp (skin permeability)-1.4💻 Calculated
SMILESCC(C)CCCC1=NC=CN=C1OC🔬 PubChem

Volatility & Performance

Fragrance NoteHeart💻 Calculated
Volatility ClassVery slow💻 Calculated
Persistence Score3 / 5💻 Calculated

Odor & Flavor

Primary Descriptorsgreenwoody• leffingwell
Functional Groupsetheraromatic💻 RDKit

Sensory Thresholds

Odor Detection Threshold0 ppm📖 van Gemert
Data Sources & Attribution
Physical data: PubChem (NIH/NLM), U.S. EPA CompTox Dashboard, EPA OPERA models, RDKit. Odor & flavor: Arctander (Perfume & Flavor Chemicals), Fenaroli's Handbook of Flavor Ingredients, Leffingwell. Thresholds: van Gemert (Compilations of Odour Threshold Values). Regulatory: IFRA Standards 51st, FEMA GRAS. Trade names: Surburg (Common Fragrance & Flavor Materials). All data compiled and cross-referenced for perfumertools.com.

Physicochemical Properties

DTXSID: DTXSID3071779

Physical Properties

Molecular Weight 194.278 g/mol🔬 EPA CompTox
Density 1.01 g/cm^3📊 OPERA
Boiling Point 262.416 °C📊 OPERA
Melting Point 63.733 °C📊 OPERA
Flash Point 109.219 °C📊 OPERA
Refractive Index 1.486 Dimensionless📊 OPERA
Molar Volume 199.104 cm^3/mol📊 OPERA

Partition & Solubility

LogP (Octanol-Water) 2.438 Log10 unitless📊 OPERA
LogD (pH 5.5) 2.438 Log10 unitless📊 OPERA
LogD (pH 7.4) 2.438 Log10 unitless📊 OPERA
LogKoa (Octanol-Air) 6.56 Log10 unitless📊 OPERA
Water Solubility 0.003 mol/L📊 OPERA
Henry's Law Constant 0 atm-m3/mole📊 OPERA

Transport Properties

Vapor Pressure 0.022 mmHg📊 OPERA
Viscosity 10.699 cP📊 OPERA
Surface Tension 33.97 dyn/cm📊 OPERA
Thermal Conductivity 131.913 mW/(m*K)📊 OPERA

Molecular Descriptors

Topological Polar Surface Area 35.01 Ų💻 Computed
H-Bond Donors 0 count💻 Computed
H-Bond Acceptors 3 count💻 Computed
Rotatable Bonds 5 count💻 Computed
Aromatic Rings 1 count💻 Computed
Molar Refractivity 57.153 cm^3/mol📊 OPERA
Polarizability 22.657 Å^3📊 OPERA

Data Sources:

🔬 EPA Experimental data from U.S. EPA CompTox Chemicals Dashboard & CTX APIs. 📊 OPERA Predicted using EPA's OPERA QSAR models. 💻 Computed Calculated from SMILES using RDKit.

Similar Posts