Studies of the Essential Oil of Mentha rotundifolia

Part I. Isolation of Rotundifolone, a New Terpenic Ketone

Abstract

Rotundifolone, a new terpenic ketone, C₁₀H₁₄O₂ has been isolated from the essential oil of M. rotundifolia in Japan. This ketone is highly dextro-rotatory, and has a low melting point 27.5° The wave lengths of the ultraviolet absorption maxima of rotundifolone and its semicarbazone are 260mμ (log ε=3.95) and 273mμ (log ε=4.12) respectively. This indicates that rotundifolone has an α, β-unsaturated carbonylic system.