The present invention relates to compounds of the formula (I) and the formula (Ia) ##STR00001## wherein R.sub.1, R.sub.2 and R.sub.3 mutually independently mean hydrogen or methyl, odoriferous and/or aroma substance compositions comprising one or more compounds according to the invention of the formula (I) and/or formula (Ia), perfumed products and aromatized products in each case comprising one or more compounds according to the invention of the formula (I) and/or formula (Ia), and to uses of one or more compounds according to the invention of the formula (I) and/or formula (Ia) as odoriferous and/or aroma substances and methods of producing compounds according to the invention of the formula (I) and formula (Ia).