The present invention provides compounds that modulate biological metals and to pharmaceutical compositions containing such compounds. The invention particularly relates to imidazo[1,5-a]pyridine compounds of formula (I) that modulate iron and are useful for the treatment of diseases, particularly neurological diseases such as Parkinson's disease (PD), Alzheimer's disease (AD), Alzheimer-type dementia, Huntington's disease (HD), amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD) and multiple system atrophy (MSA). The compounds of formula (I) being where variables are defined herein.