ISOQUINOLINE DERIVATIVES OR SALTS THEREOF

摘要

The present invention relates to a novel isoquinoline derivative or its salt having the following formula: (see formula I) wherein: A: lower alkylene; B: -C(=O) -NR5- or -NR5-C (=O)-; R1 and R2: hydrogen atom, lower alkyl or -O-lower alkyl, which may be the sa me or different; R3, R4 and R5: hydrogen atom or lower alkyl, which may be the same or different; ring D: optionally substituted hydrocarbon ring or optionally substituted hetero ring; m: 1, 2 or 3; n: O or 1; and q: 1 or 2. The isoquinoline derivative has an I f current inhibitory effect without serious side effects and is particularly useful as a cardiac rate lowering agent for preventing ischemic heart diseases such as angina and cardiac infarction and circulatory diseases such as congestive cardiac insufficiency and arrhythmia .