Hiroshi Ohtaka

Selective effect of KB-2796, a new calcium entry blocker, on cerebral circulation : a comparative study of the effects of calcium entry blockers on cerebral and peripheral arterial blood flows

The effects of a new calcium entry blocker, KB-2796, on cerebral and peripheral circulation were compared with those of four other calcium entry blockers (flunarizine, cinnarizine, nicardipine, and diltiazem) and also papaverine in anesthetized dogs. KB-2796 increased the vertebral blood flow to the same extent as the other drugs. KB-2796 and the other drugs increased the coronary blood flow, although the effect of KB-2796 was obviously weaker than that of the other drugs. The dose of KB-2796 producing a 30% increase in coronary blood flow was about 20 times higher than that producing an equivalent increase in vertebral blood flow. KB-2796 and the other calcium entry blockers caused a moderate increase in both femoral and common carotid blood flow. The renal artery showed a biphasic response to all drugs, which consisted of an initial decrease and a subsequent increase in the flow. From these results, it is suggested that KB-2796 is a new type of calcium entry blocker that selectively affects the cerebral circulation. It is also concluded that calcium entry blockers have a different spectrum of vasodilatory action on coronary and cerebral vascular beds and that a selective coronary vasodilatory action is not a common feature among all calcium entry blockers.

Benzylpiperazine compound and pharmaceutical composition as hypolipidemic agent

Novel benzylpiperazine compound of the formula: ##STR1## or a pharmaceutically acceptable acid addition salt thereof, which has excellent hypolipidemic activity without undesirable side effect, and a pharmaceutical composition containing the compound as an active ingredient suitable for the prophylaxis and treatment of hyperlipidemia.

Reaction of quinazoline-2,4(1H,3H)-dione with N-substituted cyclic amines in combination with phosphoryl trichloride

The reaction of quinazoline-2,4(1H,3H)-dione with N-allyl, N-benzyl and N-methyl cyclic amines in combination with phosphoryl trichloride in the presence of tripropylamine in 1,4-dioxane afforded 4-chloro-2-(cycloalkylamino)quinazolines. In the case of N-substituted pyrrolidines, 4-chloro-2-(N-substituted 4-chlorobutylamino) quinazolines were also obtained.