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Tetra(arylalkynyl)pyridines and tetra(arylalkenyl)pyridines and their benzene analogues were prepared by palladium‐catalyzed cross‐coupling reactions from the commercially available chlorinated substrates in good to excellent yields. The photophysical properties of selected compounds were investigated and compared to each other. Very good fluorescence quantum yields were observed, especially for the pyridine derivatives.

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.

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Synthesis of 3,4-Fused Coumarins. -(IAROSHENKO*, V. O.; ERBEN, F.; MKRTCHYAN, S.; HAKOBYAN, A.; VILCHES-HERRERA, M.; DUDKIN, S.; BUNESCU, A.; VILLINGER, A.; SOSNOVSKIKH, V. Y.; LANGER, P.; Tetrahedron 67 (2011) 41, 7946-7955, http://dx.

The presented article is focused on the study of the lullaby and grounds for the existence of subtypes within the genre, which clearly differ from each other in their structure and composition principles. Observations on this subject can be seen in the works of Komitas, later in the works of musicologists Robert Atayan, Margarita Brutyan, Mushegh Aghayan, Hasmik Apinyan, as well as in the works of ethnographers Roza Grigoryan and Hripsime Pikichyan. We attempted to combine their observations and propose our own approach, as well as to classify these groups of lullabies by type, based on a comprehensive analysis. Among other academic achievements of Komitas, it should be noted that he made the first attempt at genre classification of Armenian traditional music, in which, however, the lullaby is not yet recognized as an independent phenomenon. Komitas divided the lullabies into two groups; one of which he considered a component of women’s lyrical song and the other a component of the women’s work song․