5-Methyl-6,7-dihydro-5H-cyclopentapyrazine

What 5-Methyl-6,7-dihydro-5H-cyclopentapyrazine smells like

JECFA, as published by PubChem, describes 5-methyl-6,7-dihydro-5H-cyclopentapyrazine as a light yellow to amber liquid with a peanut odour. PubChem lists nutty pyrazine among its synonyms and links it to a natural-product database (KNApSAcK). A Perfumer & Flavorist profile describes it as roasted and peanut with a slight earthy touch, strong in use and relatively heat-stable, and Perflavory lists earthy, baked potato, roasted and peanut.

Leading note

Peanut

Supporting facets

Roasted

Character

Nutty

• peanut
• nutty
• roasted

What makes 5-Methyl-6,7-dihydro-5H-cyclopentapyrazine distinctive

A pyrazine that reads as roasted peanut.

How 5-Methyl-6,7-dihydro-5H-cyclopentapyrazine is used

Perfumer & Flavorist describes it as strong in use and relatively heat-stable, and JECFA has evaluated it as a flavouring agent. In perfumery it is used in traces for roasted-peanut, earthy and baked effects in chocolate and gourmand accords.

Typical role: modifier (used in small amounts to change the character of a blend).

How 5-Methyl-6,7-dihydro-5H-cyclopentapyrazine differs from similar materials

2-Acetylpyrazine

Acetylpyrazine is popcorn and roasted grain; nutty pyrazine is described as peanut.

Each difference compares the published descriptions of the two materials. Smell varies with grade, supplier and dilution; compare them side by side on blotters before substituting one for another.

Formulation considerations

Potent; the formulas use it at 0.1-1%.

Identity and classification

Type

Aroma chemical

Origin

Occurs in nature

Odour family

Gourmand

Note position

Heart note

Physical form at room temperature

Liquid

Also known as

Nutty pyrazine

CAS number

23747-48-0

Molecular formula

C8H10N2

Molecular weight

134.18 g/mol

IUPAC name

5-methyl-6,7-dihydro-5H-cyclopenta[b]pyrazine

The CAS number, formula and molecular weight are taken from PubChem compound 32065, 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 classify it (1,501 reports): H302 harmful if swallowed (96.7% of reports). 1 of the reports find it does not meet the hazard criteria. 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

• 2,3,5-Trimethylpyrazine

  Aroma chemical · Gourmand — roasted, nutty, cocoa, earthy

• 2-Acetylpyrazine

  Aroma chemical · Gourmand — popcorn, roasted, nutty, bready

• Filbertone

  Aroma chemical · Gourmand — hazelnut, nutty, metallic, buttery

Used in formulas and accords

Used in 4 published formulas

5-Methyl-6,7-dihydro-5H-cyclopentapyrazine is an ingredient in 2 perfume formulas, 1 accord and 1 base in the Formula & Accord Library.

Community formulas

• Banana Bread

  Community Formula · listed as “Nutty Pyrazine 0.1%”, at 0.1%

• Cappuccino Accord

  Community Formula · Accord · listed as “Nutty Pyrazine 1%”, at 1%

• Pistachio Base

  Community Formula · Base · listed as “Nutty Pyrazine 0.1%”, at 0.1%

RUŌOD House Originals

Original compositions by RUŌOD House.

• Ginger Biscuit Tin

  RUŌOD House Original · listed as “5-Methyl-6,7-dihydro-5H-cyclopentapyrazine 1% DPG”, at 1% in DPG

Further reading

• Building a Gourmand Accord: Vanilla, Caramel and Beyond

  The materials of gourmand perfume — vanillin, ethyl maltol, coumarin, lactones, roasted notes — how to keep them wearable, and color and crystal problems.

Questions about 5-Methyl-6,7-dihydro-5H-cyclopentapyrazine

Sources

• PubChem — compound 32065, checked 24 October 2026.
• PubChem — GHS classification (the ECHA C&L Inventory notifications and any harmonised EU entry), read 26 October 2026.
• PubChem — 5-Methyl-6,7-dihydro-5H-cyclopentylpyrazine (CID 32065): JECFA organoleptic description — odour database.
• Perfumer & Flavorist — Flavor Bites: 5-methyl-6,7-dihydro-5H-cyclopentapyrazine — published literature.
• Perflavory — 5-methyl-6,7-dihydro-5H-cyclopentapyrazine — odour database.
• 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.