Terpenes from Cantinoa (Lamiaceae) native to Rio Grande do Sul, South Brazil

Abstract Cantinoa althaeifolia, C. heterodon, C. mutabilis, C. stricta and C. sylvularum were investigated for the essential oil and exudate composition. The essential oils of these species, previously placed in the genus Hyptis, demonstrated the presence of at least 46 compounds, being β-pinene, δ-3-carene, β-caryophyllene, bicyclogermacrene, caryophyllene oxide and globulol the compounds present in higher amounts. Besides monoterpenes and sesquiterpenes, three species presented diterpenes. Kaurenoic acid was isolated from C. heterodon exudate and detected by gas chromatography in C. stricta and C. mutabilis. Although kaurane diterpenes are widely found in nature, their occurrence in Lamiaceae seems to be restricted to few genera.