With respect to 1,2,3,4-tetrahydro-2,4-dioxoquinazoline derivatives having a 1-(6,7-dimethoxy-4-quinazolinyl)-4-piperidinyl group at the 3-position, those having a hydrogen atom, a chlorine atom or a nitro group at the 6-position are described in Chem.  Pharm.  Bull.,  38, 1591-1595 (1990).  Further, it is known that a compound having adenosine uptake inhibitory activity exhibits myocardium protecting activity [Circul.,  80, 1400-1411 (1989); Am.  J. Physiol.,  H1570-1577 (1991); J. Cardiovasc.  Pharmacol.,  20, 173-178 (1992)].