Pentaarylpyridines were conveniently prepared in one step by pentafold Suzuki-Miyaura reactions of pentachloropyridine. Moreover, site selective reactions were performed, leading to various substituted arylpyridines. Pentaarylpyridines were studied in detail by means of DFT calculations and by optical spectroscopy.

The palladium‐catalyzed CH activation and arylation of N‐methylpyrrole and N‐phenylpyrrole allowed a convenient synthesis of diarylpyrroles. The reactions were performed by using tetrabutylammonium acetate as an ionic solvent, which allowed for the application of a ligand‐free catalytic system by using simple palladium salts or polyvinylpyrrolidone‐stabilized palladium nanoparticles as the catalyst.

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The first synthesis of 3-(dichloroacetyl)chromone from 3-(dimethylamino)-1-(2-hydroxyphenyl)propen-1-one and dichloroacetyl chloride is described. The reaction of electron-rich aminoheterocycles with 3-(dichloroacetyl)chromone provides a set of diverse fused pyridines bearing the CHCl 2 -substituent at the a-position of the pyridine core. Subsequent hydrolysis leads to the formation of annulated a-(formyl)pyridines.Purine isosteres and purine-like scaffolds are of considerable interest as major privileged scaffolds 1 often used in medicinal chemistry and drug design. In the past decade, functionalized derivatives of purine isosteres have proved to be of high pharmacological importance as lead structures and synthetic building blocks in medicinal and agricultural chemistry. [2][3][4][5][6][7][8] At the same time, purine-like scaffolds, bearing a carbonyl function 9 at the 2-position of the purine core, are considered as a promising heterocyclic platform for the design of inosine 5¢-monophosphate dehydrogenase (IMPDH) inhibitors. IMPDH is considered as an important target enzyme for drug design. 9,10 In our present study we have developed a preparative approach to purine isosteres bearing a formyl function located at the 2-position of the purine/pseudo-purine core.Retrosynthetically, structures of this type can be assembled by annulation of the a-formyl-substituted pyridine ring with an aminoheterocyclic moiety. As 1,3-C,N-dinucleophiles, which are suitable for this purpose, we envisaged electron-rich hetarylamines 1-10 ( Figure 1) and 1,1-dichloro-4-ethoxybut-3-en-2-one (11) 11 as a 1,3-C,C-dielectrophile. With this concept in hand, we began to investigate the reaction of amines 1-10 with building block 11.Unfortunately, many reactions of 11 with aminoheterocycles did not give satisfactory results as, in most cases, complex product mixtures were formed which could not be separated by preparative column chromatography. Only amines 1a and 5 reacted smoothly with 11 leading to pyridine ring annulation. In these cases, the reactions gave 6-(dichloromethyl)-2-phenyl-1,2-dihydro-3H-pyrazolo[3,4-b]pyridin-3-one (12) and 5-(dichloromethyl)-1-methyl-3-phenyl-1,3-dihydro-2H-imidazo[4,5-b]pyridine-2-thione (13) bearing a CHCl 2 substituent located at the aposition of the annulated pyridine ring. Figure 1 Structures of the 1,3-C,N-dinucleophiles usedN N NH 2 O R 1 N NH 2 R NC N S NH 2 Alk 2 N NH 2 MeO N N NH 2 Ph N N O R 1 R 2 O NH 2 N N NH 2 Ph S Me 1 a R 1 = Ph, R 2 = H 1 b R 1 = Me, R 2 = H 1 c R 1 = H, R 2 = Me 3 a Alk 2 N = piperidino 3 b Alk 2 N = morpholino 3 c Alk 2 N = NMe 2 2 a R = 4-MeOC 6 H 4 CH 2 2 b R = c-Hex 2 c R = t-Bu 6 a R 1 = H, R 2 = H 6 b R 1 = Me, R 2 = Me 6 c R 1 = H, R 2 = Me NH 2 Me 2 N 9 OMe NH 2 MeO 8 OMe MeO 4 5 1 0 NH 2 MeO MeO 7 R 2 Downloaded by: University of Liverpool. Copyrighted material.

Natural L-carvone was utilized as a starting material for an efficient synthesis of some terpenyl-derived 1,2,3-triazoles. Chlorination of carvone, followed by nucleophilic substitution with sodium azide resulted in the preparation of 10-azidocarvone. Subsequent CuAAC click reaction with propargylated derivatives provided an efficient synthetic route to a set of terpenyl-derived conjugates with increased solubility in water. All investigated compounds exhibit high antioxidant activity, which is comparable with that of vitamin C. It was also found that serum albumin and the terpenyl-1,2,3-triazoles hybrids spontaneously undergo reversible binding driven by hydrophobic interactions, suggesting that serum albumin can transport the target triazoles.