摘要 |
2-R3RN-3-R1R'N-5-PY-6-Q-pyridines (I) or pharmaceutically-acceptable acid-addition salts thereof are useful as intermediates in the preparation of 1- or 3-substituted-1,3-dihydro-5-Q-6-PY-2H-imidazo[4,5-b]pyridin-2-ones or -2-thiones and also as intermediates for preparing 1- or 3-substituted-5-Q-6-PY-3H(or 1H)-imidazo[4,5-b]pyridines, where R1, R3, R, R', PY and Q are defined hereinbelow. Also shown are processes for preparing I and the following intermediates used therein: 2-halo-3-nitro-5-PY-6-Q-pyridines (III), 2-R3RN-3-nitro-5-PY-6-Q-pyridines (V), 2-halo-5-PY-6-Q-pyridines (VII), 2-R3RN-5-PY-6-Q-pyridines (VIII) and 2-R3RN-3-halo-5-PY-6-Q-pyridines (IX) or salts thereof. Certain embodiments of II and VIII also are useful as cardiotonics and are shown as active components of cardiac compositions and methods for increasing cardiac contractility. |