A series of 2-methyl-3-amino-4(H)-quinazolinone and of 2-phenyl-3-amin
o-4(H)-quinazolinone derivatives were synthesized and examined for the
ir CCK receptor affinities. These compounds displayed micromolar affin
ities for CCK-B rather than CCK-A receptor and the obtained results co
nfirm that the 4(3H)-quinazolinone nucleous represent a useful templat
e for the development of selective CCK-B receptor ligands.