Results 221 to 230 of about 14,524 (254)

Pyridazines. XXIII. A novel pyridazine into pyrazole ring transformation

Journal of Heterocyclic Chemistry, 1984
AbstractTreatment of phenyl(4‐pyridazinyl)methanols 1a and 1b with p‐toluenesulfonic acid at elevated temperatures causes transformation into the C‐4 substituted pyrazole derivatives 8a and 8b. Limitations of this novel rearrangement reaction as well as mechanistic considerations are discussed.
Gottfried Heinisch, Richard Waglechner
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ChemInform Abstract: Synthesis of New Pyridazin‐6‐ones, Pyridazin‐6‐imines, 4‐Pyridazinals, and Pyridines.

ChemInform, 2002
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Samia M. Sayed, Mohamed A. Khalil, Maghraby A. Ahmed, Mohamed A. Raslan   +3 more
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[Biotransformation of pyridazines. 1. Pyridazine and 3-methylpyridazine].

Die Pharmazie, 1990
Pyridazin (1) and 3-methylpyridazine (6) undergo oxidative biotransformation in an unexpected high degree. Beside the unchanged compounds, after administration of 1 two isomeric monohydroxylated products (2, 3), 4,5-dihydrodihydroxypyridazine (4) and 4,5-dihydroxypyridazine (5) and after administration of 6 one ringhydroxylated 6-derivative (7), 3 ...
H H, Borchert, S, Pfeifer, B, Helbig, P, Franke, G, Heinisch   +4 more
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Pyridazines. XLVI. Ring Opening of Some Azolo and Azino Pyridazines

Synthetic Communications, 1971
Abstract A facile cleavage of the five-membered ring of certain quaternary s-triazolo (4, 3-b)pyridazines under basic conditions was recorded recently2. We report now several interesting cases of the six-membered ring opening in some related systems under similar conditions.
A. Pollak, B. Stanovnik, M. Tišler
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Pyridazine-derived γ-secretase modulators

Bioorganic & Medicinal Chemistry Letters, 2011
SAR of a novel series of pyridazine-derived γ-secretase modulators is described. Compound 25 was found to be a potent modulator in vitro, which on further profiling, was found to decrease Aβ42 and Aβ40, and maintain the levels of total Aβ. Furthermore, 25 demonstrated excellent pharmacokinetic parameters as well as good CNS penetration in the rat.
Zehong, Wan, Adrian, Hall, Yun, Jin, Jia-Ning, Xiang, Eric, Yang, Andrew, Eatherton, Beverley, Smith, Guang, Yang, Haihua, Yu, Ju, Wang, Liang, Ye, Lit-Fui, Lau, Ting, Yang, William, Mitchell, Wei, Cai, Xiaomin, Zhang, Yingxia, Sang, Yonghui, Wang, Zhaolong, Tong, Ziqiang, Cheng, Ishrut, Hussain, John D, Elliott, Yasuji, Matsuoka   +22 more
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Pyridazines

2021
Jie Jack Li, Minmin Yang
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Pyridazines. XXXVII. Pyrimido[1,2-b]pyridazines

The Journal of Organic Chemistry, 1971
Miha Tisler, Alfred Pollak, Branko Stanovnik   +2 more
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Chapter 13 Pyridazines

2007
Publisher Summary The pyridazine nucleus is a π-deficient aromatic heterocycle. Each nitrogen atom of the 1,2-diazine activates its α- and γ-position for nucleophilic attack. Consequently, all ring carbon atoms are deactivated for electrophilic substitution.
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Pyridazines XXIV

Tetrahedron, 1985
Gottfried Heinisch, Gerhard Lötsch
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Pyridazines

1968
M. Tišler, B. Stanovnik
openaire   +1 more source