1 Results Selective inhibition of protein tyrosine kinases is gaining importance as an effective therapeutic approach for the treatment of a wide range of human cancers.The epidermal growth factor receptor (EGFR) protein tyrosine kinase is one of the important kinases that play a fundamental role in cell growth signal pathways.We focused on the 4-anilinoquinazoline framework,which is observed in both compounds as a common structure.A boron atom has a vacant orbital and interconverts with ease between the neutral sp2 and the anionic sp3 hybridization states.This generates a new stable interaction between the boron atom and a donor molecule through a covalent bond.Therefore,it is expected that the boron atoms introduced into quinazoline framework would interact with a target protein not only through hydrogen bonds but also through covalent bonds,which would produce potent biological activity We introduced a boronic acid moiety into R1 and R3 groups as shown in Scheme 1. 1 Results Selective inhibition of protein tyrosine kinases is gaining importance as an effective therapeutic approach for the treatment of a wide range of human cancers. Epidermal growth factor receptor (EGFR) protein tyrosine kinase is one of the important kinases that play a fundamental role in cell growth signal pathways. We focused on the 4-anilinoquinazoline framework, which is observed in both compounds as a common structure. A boron atom has a vacant orbital and interconverts with ease between the neutral sp2 and the anionic sp3 hybridization states. this generates a new stable interaction between the boron atom and a donor molecule through a covalent bond. Wherefore, it is expected that the boron atoms introduced into quinazoline framework would interact with a target protein not only through hydrogen bonds but also through covalent bonds, which would produce potent biological activity We introduced a boronic acid moiety into R1 and R3 groups as shown in Scheme 1.