The present invention relates to certain ester and nitrile derivatives of formula (I): wherein one dotted line represents a carbon-carbon single or double bond and the other dotted lines each represent a carbon-carbon single bond R1 is a hydrogen atom or a methyl group, R2 is a methyl or ethyl group, R3 is a hydrogen atom or a methyl group, R4 is a hydrogen atom or a methyl group or said R4 taken together with the bond between carbon atom 2 and 3 form a cyclopropane and X represents a CN or a COOR5 group, R5 representing a C1-5 alkyl group with the compound being in the form of any one of its pure stereoisomers or mixtures thereof. These compounds are useful perfuming ingredients.
