| 摘要 |
<p>Novel 5-A-pyrazolo[3,4-b)pyridines which are unsubstituted in the 4-position and in which A is amino or acylamino such as those of formula <FORM:1115254/C2/1> where R1 is alkyl or phenyl and R is H alkyl or phenyl and acyl groups include alkanoyl, mono- or dichloro-alkanoyl, morpholinoalkanoyl, benzoyl, chloro- or trimethoxybenzoyl, nicotinoyl, thiocarbamoyl and N1-benzoylthiocarbamoyl and acid addition salts thereof are prepared by Hofmann degradation of the corresponding 5-carbamoyl compound optionally followed by introduction of the acyl group and/or salt formation. 5 - Carbamoyl - 1 - R - 2 - R1 - pyrazolopyridines are prepared from the corresponding carboxylic acids which are obtained by hydrolysis of their esters. 5 - Carbethoxy - 1 - R - 2 - R1 - pyrazolopyridines are obtained by dechlorination with hydrogen of the corresponding 4-chloro compound which is obtained by chlorination of the 4-hydroxy compound. 5 - Carbethoxy - 4 - hydroxy - 1 - R - 2 - R1-pyrazolopyridines are prepared by cyclization of N(1 - R - 3 - R1 - 5 - pyrazole) - aminomethylene malonic acid diethyl ester which is obtained by condensation of ethoxymethylene malonic acid diethyl ester and the 5-aminopyrazole. 5 - Amino - 3 - phenyl - pyrazole is prepared by condensation of methyl hydrazine and benzoylacetonitrile. Pharmaceutical compositions in conventional forms for oral or parenteral administration useful as vasodilators and cardiotonics comprise an above novel compound and a pharmaceutical excipient.</p> |
