Abstract: 2-Q-6-Q'-8-R-pyrido[2,3-d]pyrimidin-5(8H)-ones (I), where Q is 4(or 3)-hydroxyphenyl, 4(or 3)-methoxyphenyl, 4(or 3)-pyridinyl or 4(or 3)-pyridinyl having one or two lower-alkyl substituents, R' is hydrogen or alkyl having one to four carbon atoms, Q is hydrogen, amino or nitro, and R is alkyl having from one to four carbon atoms, CH(C.sub.2 H.sub.5).sub.2, (CH.sub.2).sub.n .dbd.CHCH.sub.2 where n is 1 or 2, or Y--Z where Y is alkylene having from two to four carbon atoms and having its connecting linkages on different carbon atoms and Z is hydroxy, OR.sub.1 or NR.sub.1 R.sub.2 where R.sub.1 and R.sub.2 are each methyl or ethyl, or acid-addition salts thereof, and their preparation are shown. Also shown is the cardiotonic use of I where Q is 4(or 3)-hydroxyphenyl, 4(or 3)-pyridinyl or 4(or 3)-pyridinyl having one or two lower-alkyl substituents and Q' is hydrogen or amino.

Abstract: 1-R-5-Ar-1,6-naphthyridin-2(1H)-ones (I) or salts thereof, where R is hydrogen or methyl, and Ar is phenyl or phenyl substituted by methyl, ethyl, methoxy, ethoxy, hydroxy, amino, acetylamino, methanesulfonylamino, bromo, chloro, fluoro, cyano or carbamyl are useful as cardiotonic agents and corresponding compounds where Ar is nitrophenyl are useful as intermediates. Also shown as intermediates, are 5-(Ar--CO)-6-[2-(di-lower-alkylamino)-ethenyl]-2(1H)-pyridinones (II) or salts thereof, where Ar is phenyl or phenyl substituted by methyl, ethyl, methoxy, ethoxy, bromo, chloro, fluoro, cyano or nitro and 5-(Ar--CO)-6-methyl-2(1H)-pyridinones (III) where Ar is phenyl or phenyl substituted by methyl, ethyl, methoxy, ethoxy, bromo, chloro, fluoro, hydroxy, cyano or nitro; said compounds (III) where Ar is phenyl or hydroxyphenyl also are useful as cardiotonic agents. Processes for preparing the compounds of formulas I, II and III are shown.

Abstract: 1-R"-3-Q-4-R'-5-R-1,6-naphthyridin-2(1H)-ones (I) or salts thereof, where R is lower-alkyl, R' is hydrogen or methyl, R" is hydrogen or lower-alkyl, and Q is hydrogen, hydroxy, amino, cyano, carbamyl, carboxy or aminocarbamyl, are useful as cardiotonic agents (I, Q is hydrogen, hydroxy, amino, cyano or carbamyl) and/or intermediates therefor (I, Q is carboxy, aminocarbamyl, hydrogen, amino, cyano or carbamyl). Also shown are 3-Q'-4-R'-5-(RCO)-6-[2-di-lower-alkylamino)ethenyl]-2(1H)-pyridinones (II) or salts thereof, where R and R' are as above and Q' is hydrogen or cyano, which are useful as cardiotonics (II, Q' is hydrogen) and/or intermediates (II, Q' is cyano or hydrogen). Processes for preparing the compounds of formulas I and II are shown.

Abstract: 1-R.sub.1 -3-amino-5-(3-R'-4-R"-phenyl)-6-R-2(1H)-pyridinones or salts thereof, which are useful as cardiotonics, where R.sub.1 is hydrogen, lower-alkyl, or lower-hydroxyalkyl, R is hydrogen or lower-alkyl, and, R' and R" are each hydrogen, hydroxy or amino at least one of R' or R" being other than hydrogen, are prepared by reacting the corresponding 3-carbamyl compound with a reagent capable of converting carbamyl to amino or by first reacting the corresponding 3-carbamyl compound where R' and R" are each hydrogen, nitro or lower-alkoxy at least one of R' and R" being other than hydrogen with a reagent capable of converting carbamyl to amino and then reacting the resulting 3-amino compound where R' and/or R" are/is lower-alkoxy and/or nitro with a reagent capable of converting lower-alkoxy to hydroxy and/or with a reagent capable of converting nitro to amino. Preparation of the corresponding 3-carbamyl and 3-cyano compounds is shown, the latter including cardiotonically active novel 1-R.sub.

Abstract: 3-Q-4-R.sub.2 -5-(2-Q'-5-R.sub.3 -4-thiazolyl)-6-R.sub.1 -2(1H)-pyridinones (I), where R.sub.1 is alkyl having from one to four carbon atoms, R.sub.2 is hydrogen or methyl, R.sub.3 is hydrogen or alkyl having from one to three carbon atoms, Q is amino, carbamyl, carboxy, cyano or hydrogen, and Q' is alkyl having from one to four carbon atoms, amino or R.sub.4 NH where R.sub.4 is alkyl having from one to four carbon atoms, or acid-addition salts thereof where at least one of Q and Q' is amino or Q' is R.sub.4 NH, are useful as cardiotonics (I where Q is amino, cyano or hydrogen) and/or as intermediates (I where Q is cyano, carbamyl or carboxy). Also shown as intermediates are 1,2-dihydro-4-R.sub.2 -5-[R.sub.3 CH(Br)CO]-6-R.sub.1 -2-oxo-3-pyridinecarbonitriles (II), and, also, processes for preparing I and II.

Abstract: 4-R'-5-Q-1,6-naphthyridin-2(1H)-ones (I), where R' is hydrogen or methyl and Q is hydroxymethyl, 1-hydroxyethyl alkanoyloxymethyl or 1-alkanoyloxyethyl, are produced by first reacting 4-R'-5-acetyl(or n-propanoyl)-6-[2-(di-lower-alkylamino]-2(1H)-pyridinone [III] with hydroxylamine or salt thereof to produce 4-R'-5-Q'-1,6-naphthyridin-2(1H)-one-6-oxide (II), where R' is defined as above and Q' is methyl or ethyl; next reacting II with an alkanoic anhydride to produce I where Q is alkanoyloxymethyl or 1-alkanoyloxyethyl; and, then hydrolyzing said alkanoyloxymethyl or -ethyl compound to produce I where Q is hydroxymethyl or 1-hydroxyethyl. Also shown is the cardiotonic use of II and I where Q is hydroxymethyl, 1-hydroxyethyl or alkanoyloxymethyl.

Abstract: 4-R.sub.2 -5-(Lower-alkanoyl)-6-(lower-alkyl)-2(1H)-pyridinones (I), useful as cardiotonics, where R.sub.2 is hydrogen or methyl, are prepared by reacting 2-(lower-alkanoyl)-1-(lower-alkyl)ethenamine (II) with lower-alkyl 2-propynoate or 2-butynoate respectively or by hydrolyzing 4-R.sub.2 -5-(lower-alkanoyl)-6-(lower-alkyl)-1,2-dihydro-2-oxonicotinonitrile (III), Q is CN) or corresponding 4-R.sub.2 -5-(lower-alkanoyl)-6-(lower-alkyl)-1,2-dihydro-2-oxonicotinamide to produce the corresponding 5-(lower-alkanoyl)-6-(lower-alkyl)-1,2-dihydro-2-oxonicotinic acid and decarboxylating said substituted nictotinic acid to produce I. Also disclosed and claimed are cardiotonic uses of 3-Q-4-R.sub.2 -5-(lower-alkanoyl)-6-(lower-alkyl)-2(1H)-pyridinones where Q is hydrogen or cyano and R.sub.2 is hydrogen or methyl (III). Also shown and claimed is methyl 4-acetyl-5-amino-2,4-hexadienoate or acid-addition salt thereof, useful as intermediate or cardiotonic.

Abstract: 1-R"-3-Q-4-R'-5-R-1,6-naphthyridin-2(1H)-ones (I) or salts thereof, where R is lower-alkyl, R' is hydrogen or methyl, R" is hydrogen or lower-alkyl, and Q is hydrogen, hydroxy, amino, cyano, carbamyl, carboxy or aminocarbamyl, are useful as cardiotonic agents (I, Q is hydrogen, hydroxy, amino, cyano or carbamyl) and/or intermediates therefor (I, Q is carboxy, aminocarbamyl, hydrogen, amino, cyano or carbamyl). Also shown are 3-Q'-4-R'-5-(RCO)-6-[2-(di-lower-alkylamino)ethenyl]-2(1H)-pyridinones (II) or salts thereof, where R and R' are as above and Q' is hydrogen or cyano, which are useful as cardiotonics (II, Q' is hydrogen) and/or intermediates (II, Q' is cyano or hydrogen). Processes for preparing the compounds of formulas I and II are shown.

Abstract: 3-Q-5-[4-(R'-X)phenyl]-6-R-2(1H)-pyridinones (I), where R and R' are each methyl or ethyl, X is sulfinyl when Q is hydrogen or cyano, or X is sulfonyl when Q is cyano, their preparation and cardiotonic use are shown. Also shown are intermediates 5-[4-(R'-thio)phenyl]-6-R-2(1H)-pyridinones (II) and also corresponding 3-cyano intermediates.

Abstract: 1-R.sub.1 -3-amino-5-(3-R'-4-R"-phenyl)-6-R-2(1H)-pyridinones or salts thereof, which are useful as cardiotonics, where R.sub.1 is hydrogen, lower-alkyl, or lower-hydroxyalkyl, R is hydrogen or lower-alkyl, and, R' and R" are each hydrogen, hydroxy or amino at least one of R' or R" being other than hydrogen, are prepared by reacting the corresponding 3-carbamyl compound with a reagent capable of converting carbamyl to amino or by first reacting the corresponding 3-carbamyl compound where R' and R" are each hydrogen, nitro or lower-alkoxy at least one of R' and R" being other than hydrogen with a reagent capable of converting carbamyl to amino and then reacting the resulting 3-amino compound where R' and/or R" are/is lower-alkoxy and/or nitro with a reagent capable of converting lower-alkoxy to hydroxy and/or with a reagent capable of converting nitro to amino. Preparation of the corresponding 3-carbamyl and 3-cyano compounds is shown, the latter including cardiotonically active novel 1-R.sub.

Abstract: Shown are 2-(NB)-4-PY-5-Q-pyrimidines (I) and 2-(NB')-5-PY-4-Q'-pyrimidines (II) or salts thereof, where PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents, Q and Q' are each hydrogen or methyl, NB is dimethylamino or N-(2-hydroxyethyl)methylamino and NB' is amino, dimethylamino, acetylamino or propionylamino; the preparation thereof; and, their cardiotonic use.

Abstract: 3-Methyl-4-(4-pyridinyl)benzeneamines, useful as cardiotonic agents, are prepared by reaction of pyridine, benzoyl chloride and an appropriate 3-methyl-N,N-di-lower-alkylbenzeneamine in the presence of copper powder and decomposing the reaction mixture with alkali and, if desired, reacting a resulting 3-methyl-4-(4-pyridinyl)N,N-di-lower-alkylbenzeneamine with hydrogen bromide and pyridine to obtain 3-methyl-4-(4-pyridinyl)benzeneamine.

Abstract: N-R-N'-R'-N-[4(or 5)-PY-2-pyrimidinyl]ureas (I) or salts thereof, where PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents, R' is hydrogen or methyl and R is methyl or ethyl when PY is attached to the 4-position of the pyrimidine ring or R is hydrogen, ethyl or n-butyl when PY is attached to the 5-position of the pyrimidine ring are useful as cardiotonic agents. The preparations of I and their cardiotonic use are shown.

Abstract: 8-Q-2-PY-9H-purin-6-amines (II), salts thereof, their preparation via 2-PY-4,5,6-pyrimidinetriamine and cardiotonic use are shown, where PY is 4-pyridinyl or 4-pyridinyl having one or two lower-alkyl substituents, and Q is methyl, ethyl, 1-methylethyl, 1,1-dimethylethyl, methylthio and ethylthio. Also shown as intermediates for the compounds where Q is methylthio or ethylthio are the corresponding 6-amino-2-PY-9H-purin-8-thiols.

Abstract: 4,5-Dihydro-4-R-6-(4-pyridinyl)-3(2H)-pyridazinone (IA) or pharmaceutically-acceptable acid-addition salt thereof, where R is hydrogen or methyl, is shown as the active component in cardiotonic composition and method for increasing cardiac contractility in a patient requiring such treatment. Also shown is the preparation of IA by reacting a lower-alkyl 2-R-4-(BN)-4-cyano-4-(4-pyridinyl)butanoate with hydrazine, where R is hydrogen or methyl, and BN is 4-morpholinyl, 1-piperidinyl or 1-pyrrolidinyl.

Abstract: 8-Q-2-PY-9H-purin-6-amines (II), salts thereof, their preparation and cardiotonic use are shown, where PY is 4-pyridinyl or 4-pyridinyl having one or two lower-alkyl substituents, and Q is methyl, ethyl, 1-methylethyl, 1,1-dimethylethyl, methylthio and ethylthio. Also shown as intermediates for the compounds where Q is methylthio or ethylthio are the corresponding 6-amino-2-PY-9H-purin-8-thiols.

Abstract: 3-Q-4-R.sub.2 -5-(2-Q'-5-R.sub.3 -4-thiazolyl)-6-R.sub.1 -2(1H)-pyridinones (I), where R.sub.1 is alkyl having from one to four carbon atoms, R.sub.2 is hydrogen or methyl, R.sub.3 is hydrogen or alkyl having from one to three carbon atoms, Q is amino, carbamyl, carboxy, cyano or hydrogen, and Q' is alkyl having from one to four carbon atoms, amino or R.sub.4 NH where R.sub.4 is alkyl having from one to four carbon atoms, or acid-addition salts thereof where at least one of Q and Q' is amino or Q' is R.sub.4 NH, are useful as cardiotonics (I where Q is amino, cyano or hydrogen) and/or as intermediates (I where Q is cyano, carbamyl or carboxy). Also shown as intermediates are 1,2-dihydro-4-R.sub.2 -5-[R.sub.3 CH(Br)CO]-6-R.sub.1 -2-oxo-3-pyridinecarbonitriles (II), and, also, processes for preparing I and II.

Abstract: Disclosed and claimed is the cardiotonic use of 1-R.sub.1 -5-(3-R'-4-R"-phenyl)-6-R-2(1H)-pyridinones (II), where R.sub.1 is hydrogen, lower-alkyl or lower-hydroxyalkyl, R is lower-alkyl or hydrogen, and, R' and R" are each hydrogen, amino or hydroxy, at least one of R' or R" being other than hydrogen, or where R' is nitro when R" is hydroxy, or pharmaceutically acceptable acid-addition salts thereof where at least one of R' and R" is amino. Also disclosed and claimed are 1-R.sub.1 -5-(3-R'-4-R"-phenyl)-6-R-2(1H)-pyridinones (I), where R.sub.1, R' and R" are defined as above and R is lower-alkyl and acid-addition salts thereof where at least one of R' and R" is amino. Also shown and claimed is the process which comprises reacting 1-R.sub.1 -1,2-dihydro-2-oxo-5-(3-R'-4-R"-phenyl)-6-R-nicotinonitrile, where R.sub.

Abstract: 2-(R.sub.1 O)-3-Q-5-PY-6-R-pyridine (I) or pharmaceutically acceptable acid-addition salts thereof are useful cardiotonics, where R.sub.1 is methyl or ethyl, R is hydrogen or lower-alkyl, PY is 4(or 3)-pyridinyl or 4(or 3)-pyridinyl having one or two lower-alkyl substituents, and Q is hydrogen, chloro or COOR' where R' is lower-alkyl, or Q is cyano only when R is hydrogen. The preparation of I and their cardiotonic use are shown.

Abstract: 3-Q-4-R'-6-R-2(1H)-pyridinones (I), where Q is hydrogen or cyano, R' is hydrogen, methyl, ethyl or n-propyl, and R is methyl, ethyl or n-propyl, are shown to be useful as cardiotonic agents.