Bicycle heteroaromatic compounds as protein tyrosine kinase inhibitors

Substituted heteroaromatic compounds, and in particular substituted biccyclic heteroaromatic compounds in which one ring is a pyridine or pyrimidine of formula (i)are protein tyrosine kinase inhibitors. The compounds are described as are methods for their preparation, pharmaceutical compositions including such compounds and their use in medicine, for example the treatment of cancer and psoriasis.