It has been found that the novel compounds of the formula
wherein R1 is phenyl substituted with 1 to 3 lower alkoxy groups or 1 to 3 halogens. R2 is hydroxy or lower alkanoyloxy, R3 and R4 are, independently, lower alkyl or, taken together, form a piperidine or pyrrolidine ring and n is 2 to 4, and pharmaceutically acceptable acid addition salts thereof are active as calcium channel blockers and, accordingly, are useful as agents for treating ischemia and as agents for lowering blood pressure. They can be preparated by reacting a compound of the formula
with a compound of the formula
and optionally lower alkoxylating the compound obtained.
A compound of the formula ##STR1## wherein R.sub.1 is phenyl substituted with 1 to 3 lower alkoxy groups, or 1 to 3 halogens; R.sub.2 is hydroxy or lower alkanoyloxy; R.sub.3 and R.sub.4 are each independently lower alkyl or together form a pyrrolidine or piperidine ring; and n is 2 to 4, and pharmaceutically acceptable acid addition salts thereof are described. The compounds of formula I are active as calcium channel blockers and accordingly, are useful as agents for lowering blood pressure, and as agents for treating ischemia.