Compounds obtainable from plants, e.g. of the genus Eucalyptus, or from microorganisms are shown to be useful as CNS activity modulators useful e.g. in the treatment of depression, for lifting mood and/or for increasing behavioural initiative and the like. This use and related aspects form embodiments of the invention. Also compounds as such are presented.The compounds useful are acylphloroglucine derivatives of the formula I,wherein the substituents are as defined in the description.
