The present invention relates to a class of fragrance precursor compounds comprising one or more of the compounds derived from the reaction of X—OH and an aldehyde or ketone, the fragrance precursor compounds being of the formula X—O—C(R)(R*)(OR**) wherein R is a C6-24 alkyl group, a C6-24 aralkyl group or a C6-24 alkaryl group; R* is H or a C6-24 alkyl group, a C6-24 aralkyl group or a C6-24 alkaryl group; R** is H or X; X—O representing a moiety derived from X—OH, and wherein X—OH is a compound selected from the group consisting of surfactants, fabric softeners, softener precursor ester amines, softener precursor amido amines, hair conditioners, skin conditions, saccharides and polymers. In a second aspect it relates to a method of preparing such precusors. Further the invention relates to compositions, comprising the precursor of the invention.