The review systemizes literature data over the past 10–15 years on the synthesis of 2-chalcogen-substituted nicotinonitriles and their derivatives from cyano(seleno,thio)acetamides and other reagents. In addition, some information on biologically active compounds of this series is given. The bibliography includes 280 references.
A new heterocyclic system, 8-oxo-3,4-diphenyl-1,6,7,8-tetrahydro-1,2,5-triazocine-5(4H)-carbothiohydrazide, has been synthesized through the hydrazinolysis of methyl 3-(4,5-diphenyl-2-sulfanylidene-1,3-oxazol-3(2H)-yl)propanoate.
A method has been developed for denitrative vinylation of 3,5-diaryl-5-hydroxypyrrolin-2-ones via microwave-assisted thermal reaction with β-nitrostyrenes. The reaction proceeds through a radical mechanism and is triggered in the absence of an initiator.
Intramolecular Dieckmann cyclization of readily available methyl 3-[(methoxycarbonyl)methyl](4-methoxybenzyl)amino-2-methylpropanoate gave methyl 1-(4-methoxybenzyl)-4-methyl-3-oxopyrrolidine-2-carboxylate which was treated with diphenyl phosphorochloridate in the presence of DIPEA in acetonitrile to afford methyl 3-[(diphenoxyphosphoryl)oxy]-1-(4-methoxybenzyl)-4-methyl-1H-pyrrole-2-carboxylate as a new building block for the synthesis of carbapenems. Methyl 1-(4-methoxybenzyl)-4-methyl-3-oxopyrrolidine-2-carboxylate was found to undergo spontaneous dehydrogenation on storage, as well as in the course of its transformation into methyl 3-[(diphenoxyphosphoryl)oxy]-1-(4-methoxybenzyl)-4-methyl-1H-pyrrole-2-carboxylate.
Bipodal and tripodal phenolate receptors based on catechol and pyrogallol as low-molecular-weight analogues of bis-calix[4]arenes have been synthesized for the first time. Tosyl protection of the phenolic hydroxy group was utilized to overcome instability of p-azidophenol at the stage of copper-catalyzed azide–alkyne cycloaddition. The protecting group was removed under microwave irradiation, which made it possible to obtain the target phenols in high yields within two hours. The structure of the synthesized compounds was confirmed by a set of physicochemical methods, and their complexing power toward the cationic dye Rhodamine 6G was studied. The binary receptor–dye systems were tested for their ability to recognize various surfactants according to a competitive displacement mechanism.
