The present invention relates to compounds of formula I shown below: wherein Q is as defined herein. The compounds of formula I act as selective positive allosteric modulators of strychnine-sensitive alpha 1-glycine receptors. The present invention further relates to the use of these compounds as therapeutic agents for the treatment and/or prevention of diseases or conditions in which strychnine-sensitive alpha 1-glycine receptor activity is implicated (such as, for example, chronic pain. The present invention also relates to processes for the preparation of these compounds and to pharmaceutical compositions comprising them.