1-R-3-(NB)-5-PY-6-Q-1H-pyrazolo[3,4-b]pyridines or pharmaceutically-acceptable acid-addition salts thereof, which are useful as cardiotonics, are prepared by reacting a 1-R-5-PY-6-Q-1H-pyrazolo[3,4-b]pyridin-3-amine with a lower-alkanoic acid and reducing agent to produce 1-R-3-(NB)-5-PY-6-Q-1H-pyrazolo[3,4-b]pyridine (I) where NB is NHR1 or NR,R2, with a mixture of formic acid and formaldehyde to produce I where NB is N(CH3)2 or with a lower-acylating agent to produce I where NB is NHAc and, if desired, reacting the 3-(NHAc) compound with a reducing agent to prepare the corresponding 3-NHR, compound, where R is lower-alkyl, lower-hydroxyalkyl, lower-acyloxy-(lower-alkyl) or lower-alkoxy-alkyl, Q is hydrogen or lower-alkyl, PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents, and NB is selected from NHR,, NR,R2 or NHAc where R, and R2 are each lower-alkyl and Ac is lower-acyl. Also shown are cardiotonic compositions and method for increasing cardiac contractility using said compounds or salts.
1-R-3-(NB)-5-PY-6-Q-1H-
吡唑并[3,4-b]
吡啶或其药学上可接受的酸加成盐是通过将 1-R-5-PY-6-Q-1H-
吡唑并[3、4-b]
吡啶-3-胺与低级烷酸和还原剂反应生成 1-R-3-(NB)-5-PY-6-Q-1H-
吡唑并[3,4-b]
吡啶 (I),其中 NB 为 NHR1 或 NR,R2;与
甲酸和
甲醛的混合物反应生成 I,其中 NB 为 N(
CH3)2;或与低级酰化剂反应生成 I,其中 NB 为 NHAc、如果需要,将 3-(NHAc)化合物与还原剂反应,制备相应的 3-NHR,化合物,其中 R 是低级烷基、低级羟基烷基、低级乙酰氧基(低级烷基)或低级烷氧基烷基,Q 是氢或低级烷基,PY 是 4-或 3-
吡啶基或具有一个或两个低级烷基取代基的 4-或 3-
吡啶基,NB 选自 NHR、NR、R2 或 NHAc,其中 R 和 R2 分别是低级烷基,Ac 是低级酰基。还显示了使用所述化合物或盐增加心脏收缩力的强心组合物和方法。