49835-53-2Relevant academic research and scientific papers
1-butyl-3-methylimidazolium bromide as a solvent and precatalyst for stetter reaction
Phungpis, Baramee,Hahnvajanawong, Viwat
, p. 2028 - 2032 (2020/09/02)
Stetter reaction between aromatic aldehydes and acrylonitrile/ethyl acrylate performing in [Bmim]Br in the presence of NaOH is described. N-Heterocyclic carbene (NHC) generates in situ is shown to be an efficient catalyst. Benzoin condensation also occured as side reaction.
4,5-Dihydro-2-methyl-6-(4-pyridinyl)-3(2H)-pyridazinone and its use as a cardiotonic
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, (2008/06/13)
2-R-4,5-dihydro-4-R'-6-PY-3(2H)-pyridazinones (I) or salts thereof, which are useful as cardiotonics, where R is lower-alkyl or lower-hydroxyalkyl, R' is hydrogen or lower-alkyl, and PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents, are prepared by reacting 4-oxo-4-PY-2-R'-butanenitrile with an N-R-hydrazine salt of a strong inorganic acid or organic sulfonic acid or by reacting a lower-alkyl 4-oxo-4-PY-2-R'-butanoate or lower-alkyl 4-(BN)-4-cyano-4-PY-2-R'-butanoate with N-R-hydrazine where BN is 4-morpholinyl, 1-piperidinyl or 1-pyrrolidinyl. Also shown are: (a) cardiotonic compositions and a method for increasing cardiac contractility using said compounds or salts where R is lower-alkyl (b) the use of I as intermediates in preparing the corresponding 2-R-4-R'-6-PY-3(2H)-pyridazinones; and, (c) the preparation of said lower-alkyl 4-(BN)-4-cyano-4-PY-2-R'-butanoates.
3-Hydrazino-6-(pyridinyl) pyridazines and cardiotonic use thereof
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, (2008/06/13)
3-Hydrazino-6-PY-pyridazine or pharmaceutically-acceptable acid-addition salt thereof is useful as a cardiotonic agent, where PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substitutents. 6-PY-3-pyridazinol is prepared by reacting 6-PY-3-pyridazinol with a chlorinating agent to produce 3-chloro-6-PY-pyridazine and reacting said 3-chloro compound with hydrazine to produce said 3-hydrazino compound. 3-Hydrazino-6-PY-pyridazine or pharmaceutically-acceptable acid-addition salt thereof is disclosed as the active component in cardiotonic compositions for increasing cardiac contractility and in the method for increasing cardiac contractility in a patient requiring such treatment. The novel intermediate 3-chloro-6-PY-pyridazine is prepared as noted above.
4-Substituted-6-(pyridinyl)-3(2h)-pyridazinones and their use as intermediates and cardiotonics
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, (2008/06/13)
2-R-4-R'-6-PY-3(2H)-pyridazinones (I) or salts thereof, which are useful as intermediates and some as cardiotonics, are prepared by reacting di-(lower-alkyl) hydroxy[2-oxo-2-PY-ethyl]propanedioate (II) with a hydrazine salt of the formula RNHNH2.nHx An (III) to produce lower-alkyl 2,3-dihydro-2-R-3-oxo-6-PY-4-pyridazinecarboxylate (Ia where R' is lower-carbalkoxy) and reacting Ia with hydrazine hydrate or anhydrous hydrazine to produce 2,3-dihydro-2-R-3-oxo-6-PY-4-pyridazinecarboxylic acid hydrazide (Ib where R' is aminocarbamyl), where PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents, R is hydrogen, lower-alkyl or lower-hydroxyalkyl, R' is carbamyl, carboxy, aminocarbamyl or lower-carbalkoxy, n is 1 or 2, x is 1, 2 or 3, and An is an anion of a strong inorganic acid or an organic sulfonic acid. Also shown are: the preparation of II from PY--COCH3 (IV), the conversion of Ia to Ib (Id where R' is carboxy), and the use of 2-R-4-R"-6-PY-3(2H)-pyridazinones (I where R is lower-alkyl or lower-hydroxyalkyl and R" is carbamyl, aminocarbamyl or lower-carbalkoxy) as cardiotonic agents. Other intermediates are shown.
6-(Pyridinyl)-3(2H)-pyridazinones and their use as cardiotonics
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, (2008/06/13)
2-R-6-PY-3(2H)-pyridazinones (I) or salts thereof, which are useful as cardiotonics, where R is hydrogen, lower-alkyl or lower-hydroxyalkyl, and PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents, are prepared by reacting 2-R-4,5-dihydro-6-PY-3(2H)-pyridazinone with a dehydrogenating agent. Also shown are: cardiotonic compositions and a method for increasing cardiac contractility using I or salts; and, the preparation of the corresponding intermediate 4,5-dihydro compounds.
4-Amino-6-(pyridinyl)-3(2H)-pyridazinones and their use as cardiotonics
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, (2008/06/13)
4-Amino-2-R-6-PY-3(2H)-pyridazinones (I) or salts thereof, which are useful as cardiotonics, where R is hydrogen, lower-alkyl or lower-hydroxyalkyl, and PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents are prepared by: (a) reaction of 2-R-6-PY-3(2H)-pyridazinone (II) with hydrazine; (b) conversion from 2,3-dihydro-2-R-3-oxo-6-PY-4-pyridazinecarboxamide (III); or, (c) conversion form 2,3-dihydro-2-R-3-oxo-6-PY-4-pyridazinecarboxylic acid hydrazide (IV). Also shown are: the use of I or salts as cardiotonic agents; and, the preparation of intermediates.
Process for preparing ketones
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, (2008/06/13)
Ketones are prepared by reacting an aromatic or heterocyclic aldehyde in the presence of a cyanide ion with an unsaturated compound having the formula (I): STR1 wherein R1, R2 and R3 are the same or different and are selected from the group of hydrogen, optionally substituted aliphatic, cycloaliphatic, araliphatic, aromatic, heterocyclic and carboxylic acid ester and R4 is nitrile (CN), --CO--R5 or --CO--OR5 wherein R5 is selected from the group of optionally substituted aliphatic, cycloaliphatic, araliphatic, aromatic and heterocyclic and R1 and R2 and/or R1 and R3 and/or R2 and R5 or R3 and R5 together with the carbon atoms to which they are attached as substituents may also form a carbocyclic or heterocyclic ring. Ketones prepared according to the process of the invention have the formula: STR2 wherein R1 ' and R3 ' are identical or different and are selected from the group of hydrogen, lower alkyl having up to 3 C-atoms and optionally substituted phenyl; and R6 ' is optionally substituted phenyl or a pyridyl.
