| 摘要 |
<p>Compounds of the formula <IMAGE> wherein A, B, C and D are each independently -N= or -CH=, provided, however, that at least two of them must be -N=, and when A and C are both -N=, at least one or both of B and D must be -N=; and R1, R2 and R3 are substituents of diverse types; tautomers thereof; and non-toxic, pharmacologically acceptable acid addition salts thereof. The compounds are useful as cardiotonics.</p> |
