The invention concerns quinazoline derivatives of Formula I ##STR00001##
wherein R.sup.1 and R.sup.2 have any of the meanings defined in the
description; processes for their preparation, pharmaceutical compositions
containing them and their use in the manufacture of a medicament for use
as an antiproliferative agent in the prevention or treatment of tumours
which are sensitive to inhibition of erbB, particularly EGF, receptor
tyrosine kinases.