| abstract |
PCT No. PCT/JP94/00544 Sec. 371 Date Sep. 29, 1995 Sec. 102(e) Date Sep. 29, 1995 PCT Filed Apr. 1, 1994 PCT Pub. No. WO94/22442 PCT Pub. Date Oct. 13, 1994Disclosed are cardiotonic medicines containing, as the active ingredient, at least one of compounds of formula (I) and their pharmacologically acceptable salts when they form salts. wherein X1 and X2 do not exist or represents an oxygen atom; A represents OH or a C1-C4 acyloxy group; B represents a hydrogen atom or may form a chemical bond along with A; X is an oxygen atom, nitrogen, sulfur, etc.; R1 and R2 each represents a hydrogen atom, a C1-C4 alkyl group, etc.; R3 and R4 each represents a hydrogen atom, a C1-C4 alkyl group, etc., or they may together form a 1,4-butylene or 1,5-pentylene group. The compounds have a strong activity of reinforcing the contraction of cardiac muscles and a strong activity of reducing the rate of heart beats. As they are not toxic, they are useful as cardiotonic medicines. |