Synthesis of Dimethyl 1-(Hetero)aryl-4-oxo-1,4-dihydropyridazine- 3,5-dicarboxylates from Dimethyl 3-Oxopentane-1,5-dioates

Pahovnik, David; Ursic, Uros; Grošelj, Uroš; Meden, Anton; Svete, Jurij; Stanovnik, B.

doi:10.1515/znb-2008-0407

Cited by 6 publications

(2 citation statements)

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“…Apart from this, reactions of enaminones with diazonium salts giving substituted pyridazines are also described [25–28]. Our method does not require any additive, and the transformation from 1 to 2 is performed as a one-pot procedure.…”

Section: Introductionmentioning

confidence: 99%

A simple, enaminone-based approach to some bicyclic pyridazinium tetrafluoroborates

Josefík¹,

Svobodová²,

Bertolasi³

et al. 2013

Beilstein J. Org. Chem.

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SummaryEasily obtainable cyclic enaminones (piperidin-2-ylidenealkanones) can be transformed into substituted bicyclic pyridazinium tetrafluoroborates upon treatment with corresponding diazonium salts. The transformation can be performed either in a one-pot way or in a two-step process with the isolation of single azo-coupled enaminone as the intermediate. The former method is superior. Under the optimized conditions, a number of pyridazinium salts substituted with both electron-donating and electron-withdrawing substituents was easily synthesized. A mechanism of the formation of the pyridazinium salts is suggested. A partial drawback is the possibility of the formation of a mixture of products when using a different diazonium salt in each step due to a reversibility of the azo coupling. This can be suppressed by using a more reactive diazonium salt before a less reactive one.

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Section: Introductionmentioning

confidence: 99%

A simple, enaminone-based approach to some bicyclic pyridazinium tetrafluoroborates

Josefík¹,

Svobodová²,

Bertolasi³

et al. 2013

Beilstein J. Org. Chem.

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“…Combination of enaminones and diazonium salts is useful for preparation of some heterocyclic systems: pyridazinones [11], pyridazinium salts [12, 13], and some boron‐containing heterocycles [14, 15]. We also developed a method for synthesis of substituted 3‐acyl‐4‐amino‐1‐aryl‐1 H ‐pyrazoles using reaction of β‐enaminones with substituted benzenediazonium tetrafluoroborates [16].…”

Section: Introductionmentioning

confidence: 99%

Synthesis and characterization of some 3‐acyl‐4‐amino‐1‐aryl‐1H‐pyrazoles

Šimůnek

Svobodová

Macháček

2009

Journal of Heterocyclic Chem

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Online risk prediction tools for common cancers are now easily accessible and widely used by patients and doctors for informed decision‐making concerning screening and diagnosis. A practical problem is as cancer research moves forward and new biomarkers and risk factors are discovered, there is a need to update the risk algorithms to include them. Typically, the new markers and risk factors cannot be retrospectively measured on the same study participants used to develop the original prediction tool, necessitating the merging of a separate study of different participants, which may be much smaller in sample size and of a different design. Validation of the updated tool on a third independent data set is warranted before the updated tool can go online. This article reports on the application of Bayes rule for updating risk prediction tools to include a set of biomarkers measured in an external study to the original study used to develop the risk prediction tool. The procedure is illustrated in the context of updating the online Prostate Cancer Prevention Trial Risk Calculator to incorporate the new markers %freePSA and [‐2]proPSA measured on an external case–control study performed in Texas, U.S.. Recent state‐of‐the art methods in validation of risk prediction tools and evaluation of the improvement of updated to original tools are implemented using an external validation set provided by the U.S. Early Detection Research Network.

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ChemInform Abstract: Synthesis of Dimethyl 1‐(Hetero)aryl‐4‐oxo‐1,4‐dihydropyridazine‐3,5‐dicarboxylates from Dimethyl 3‐Oxopentane‐1,5‐dioates.

et al. 2008

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Pyridazine derivatives R 0500Synthesis of Dimethyl 1-(Hetero)aryl-4-oxo-1,4-dihydropyridazine-3,5-dicarboxylates from Dimethyl 3-Oxopentane-1,5-dioates. -Two reaction pathways lead to the dihydropyridazine derivatives (V). The first one involves the formation of hydrazones (III), which on treatment with dimethylformamide dimethylacetal (IV) yield the corresponding (dimethylamino)methylidene derivatives as intermediates, which immediately cyclize under the reaction conditions to give the targets (V). According to the second method, (I) is at first treated with (IV) and then reacted with diazonium salts (II) to give the same intermediates, which are cyclized without isolation into the final products (Va)-(Vd). -(PAHOVNIK, D.; URSIC, U.; GROSELJ, U.; MEDEN, A.; SVETE, J.; STANOVNIK*, B.

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Synthesis of Dimethyl 1-(Hetero)aryl-4-oxo-1,4-dihydropyridazine- 3,5-dicarboxylates from Dimethyl 3-Oxopentane-1,5-dioates

Cited by 6 publications

References 0 publications

A simple, enaminone-based approach to some bicyclic pyridazinium tetrafluoroborates

A simple, enaminone-based approach to some bicyclic pyridazinium tetrafluoroborates

Synthesis and characterization of some 3‐acyl‐4‐amino‐1‐aryl‐1H‐pyrazoles

ChemInform Abstract: Synthesis of Dimethyl 1‐(Hetero)aryl‐4‐oxo‐1,4‐dihydropyridazine‐3,5‐dicarboxylates from Dimethyl 3‐Oxopentane‐1,5‐dioates.

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