- Practical and efficient large-scale preparation of 4-methylnicotinic acid
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An efficient process for the large-scale synthesis of 4-methylnicotinic acid is developed. The synthetic route utilized 2,6-dichloro-4-methylnicotinonitrile as the starting material, which was commercially available. The key step in the sequence was the reductive dechlorination in the presence of zinc and ammonia to provide an intermediate which was hydrolyzed to the described acid. The reaction parameters optimization and improvement of purification are also presented. This approach, suitable for batch processing, is of interest basically to research laboratories and also to suppliers in the research and fine chemicals market.
- Yu, Zhaoxue,Sha, Fei,Wang, Peng
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p. 450 - 452
(2016/10/18)
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- Azaisoquinolinone derivatives as NK3 antagonists
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The invention relates to compounds useful in therapy, in particular in the treatment of psychosis, to compositions comprising said compounds, and to methods of treating diseases comprising the administration of said compounds.
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- Tetrahydropyrido[d]pyridazinones - Promising scaffolds for drug discovery
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An approach to the synthesis of all possible tetrahydropyrido[d] pyridazinones has been developed. The method relies on the catalytic hydrogenation of the corresponding aromatic counterparts, which were obtained by cyclization of the relevant dibromomethyl-substituted pyridinecarboxylates with hydrazine. The synthetic schemes include 4-5 steps starting from commercially available materials. The tetrahydropyrido[d]pyridazinone scaffolds are combinations of a saturated heterocycle (piperidine) and a privileged aromatic heterocycle (pyridazinone); hence they are promising starting points for the design in medicinal chemistry.
- Yaremenko, Anatoliy G.,Volochnyuk, Dmitriy M.,Shelyakin, Vyacheslav V.,Grygorenko, Oleksandr O.
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p. 6799 - 6803
(2013/07/26)
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- AZAISOQUINOLINONE DERIVATIVES AS NK3 ANTAGONISTS
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The invention relates to compounds useful in therapy, in particular in the treatment of psychosis, to compositions comprising said compounds, and to methods of treating diseases comprising the administration of said compounds.
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- AZAISOQUINOLINONE DERIVATIVES AS NK3 ANTAGONISTS
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The invention relates to compounds useful in therapy, in particular in the treatment of psychosis, to compositions comprising said compounds, and to methods of treating diseases comprising the administration of said compounds.
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- Herbicidal 1-pyridyltetrazolinones
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Herbicidal tetrazolinone derivatives of the formula: STR1 in which R1 is alkyl, haloalkyl, cycloalkyl, alkenyl, haloalkenyl, alkynyl or phenyl, and R2 is alkyl, haloalkyl, cycloalkyl, alkenyl, haloalkenyl, alkynyl or phenyl, or R1 and R2 together with the nitrogen atom to which they are bonded form an optionally benzofused heterocyclic ring, which is optionally substituted by C1-4 alkyl, n is 0, 1, 2 or 3, and R3 each independently is nitro, halogen, alkyl, haloalkyl, alkylthio or phenoxy.
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- The synthesis of Nauclea indole-pyridine alkaloids. 3,4-Disubstituted and 3,4,5-trisubstituted pyridines as synthetic intermediates; a total synthesis of (+/-)-decarbomethoxy-3α- and -3β-nauclechine
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Synthetic routes to a number of 3,4-disubstituted and 3,4,5-trisubstituted pyridines have been explored.These pyridines, designed to be used in the synthesis of Nauclea indole-pyridine alkaloids, are potentially useful intermediates in a number of syntheses.Particular attention has been paid to more highly substituted derivatives of 4-pyridineacetic acid, and the experimental limitations associated with their synthesis and use in subsequent reactions such as the Bischler-Napieralski cyclization have been described and explained.A synthesis of decarbomethoxynauclechine from 4-methylnicotinaldehyde avoiding these difficulties was then de signed and executed.Both diastereoisomers, (+/-)-decarbomethoxy-3α-nauclechine and (+/-)-decarbomethoxy-3β-nauclechine, were obtained; the structure and stereochemistry of each was rigorously established, but it was not possible to demonstrate which corresponded to the natural alkaloid, decarbomethoxynauclechine, reported previously.
- Shariff, Azim,McLean, Stewart
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p. 2813 - 2820
(2007/10/02)
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