Microwave-Enhanced Efficient Synthesis of Diversified 3,6-Disubstituted Pyridazines

Recent developments in supramolecular complexes of azabenzenes containing one to four N atoms: synthetic strategies, structures, and magnetic properties

For the last couple of decades, azabenzene-based ligands have drawn much attention from inorganic chemists due to their ability to coordinate with different metal ions to form supramolecular clusters. These azabenzenes are weak σ donors and strong π acceptors and electron-deficient. Metallogrid complexes and non-grid oligomers are well-defined supramolecular clusters, formed by appropriate chelating ligands, and can show interesting optical, magnetic, and electronic properties. Self-assembly of [n × n] metallogrid complexes is dominated by the entropic factor while the formation of oligonuclear metal ion complexes is dominated by other effects like CFSE, electrostatic factors, ligand conformational characters, etc. Herein, the present article gives an overview of six-membered heterocyclic azine-based ligands and their potential for different metal ions to form polynuclear complexes. Moreover, their temperature-dependent magnetic properties and SCO phenomena are well described and tabulated.

Site-selective Suzuki-Miyaura coupling of heteroaryl halides - understanding the trends for pharmaceutically important classes

Suzuki-Miyaura cross-coupling reactions of heteroaryl polyhalides with aryl boronates are surveyed. Drawing on data from literature sources as well as bespoke searches of Pfizer's global chemistry RKB and CAS Scifinder® databases, the factors that determine the site-selectivity of these reactions are discussed with a view to rationalising the trends found.

Crystal structure of 3,6-di-2-pyridinyl-4-pyridazine carbonitrile, C15H9N5

C15H9N5, monoclinic, P21/c (no. 14), a = 8.9817(4) Å, b = 11.5791(19) Å, c = 12.065(2) Å, β = 102.289(4)°, V = 1226.03(3) Å3, Z = 4, R gt (F) = 0.0533, wR ref (F 2 ) = 0.1512, T = 173(2) K.

Discovery of novel 2,6-disubstituted pyridazinone derivatives as acetylcholinesterase inhibitors

2,6-Disubstituted pyridazinone 4 was identified by HTS as a novel acetylcholinesterase (AChE) inhibitor. Under SAR development, compound 17e stood out as displaying high AChE inhibitory activity and AChE/butyrylcholinesterase (BuChE) selectivity in vitro. Docking studies revealed that 17e might interact with the catalytic active site (CAS) and the peripheral anionic site (PAS) simultaneously. Based on this novel binding information, 6-ortho-tolylamino and N-ethyl-N-isopropylacetamide substituted piperidine were disclosed as new PAS and CAS binders.

Synthesis and evaluation of highly potent GABA(A) receptor antagonists based on gabazine (SR-95531)

A selection of highly potent analogues based on the gabazine structure is described. Their syntheses are carried out in just four steps, and their potencies for antagonism at the GABA(A) receptor were measured. All antagonists showed significantly higher potencies compared to the parent competitive antagonist, gabazine.

Facile method for the combinatorial synthesis of 2,2-disubstituted quinazolin-4(1H)-one derivatives catalyzed by iodine in ionic liquids

A mild and facile method for the combinatorial synthesis of quinazolin-4-(1H)-one derivatives, containing simple 2,2-disubstituted quinazolin-4-(1H)-ones, spirocyclic quinazolin-4-(1H)-ones, spiro-heterocyclic quinazolin-4-(1H)-ones, and dispirocyclic quinazolin-4-(1H)-ones, is described, which results in high yields by using ionic liquids as green media. The method involves the reaction of 2-aminobenzamides with various ketones catalyzed by iodine and provides new quinazolin-4-(1H)-one library for biomedical screening.

A novel and convenient protocol for synthesis of pyridazines

A new flexible strategy for the synthesis of diversely functionalized pyridazines from 4-chloro-1,2-diaza-1,3-butadienes and active methylene compounds is reported. The high chemoselectivity of this approach offers access to structural precursors of GABA-A antagonist analogues.