T. V. Glukhareva

tert -Amino effect: the Meth-Cohn and Reinhoudt reactions (Review)

The data published over the last 15-20 years on reactions taking place by the tert-amino effect mechanism have been reviewed.

2-Hydroxypropyl derivatives of 1,2,3-thiadiazole and 1,2,3-triazole: Synthesis and antifungal activity*

A series of novel 5-(2-hydroxypropyl)amino-1,2,3-thiadiazole and 5-(2-hydroxy-propyl)sulfanyl-1,2,3-triazole derivatives were designed and synthesized as candidate fungicides. The new compounds were identified by NMR and IR spectroscopy, mass spectrometry, and elemental analysis. Their antifungal activities were evaluated.

Synthesis of condensed [1,2,3]triazolo-[5,1-b][1,3,4]thiadiazepine systems

In contemporary organic chemistry, rearrangements and transformations of one type of heterocycle to another are promising and convenient methods for the preparation of heterocyclic structures difficult to obtain by other means. However, these reactions are rarely used as a planned method for preparing heterocyclic systems. 1,2,3-Thiadiazoles are convenient starting materials for carrying out various rearrangements. Several rearrangements of 1,2,3-thiadiazoles involving a substituent in the ring position 5 are known [1-3], but only a few of these lead to the preparation of condensed 1,2,3-triazoles. Thus, for example, methods are known for the synthesis of [1,2,3]triazolo[5,1-b][1,3,4]thiadiazines using the Dimroth rearrangement [4, 5].

Synthesis of (1,2,3-thiadiazolyl)imidazolidine-2,4-diones by microwave irradiation and characterization of their biological activity

The effects of microwave irradiation on the synthesis of (1,2,3-thiadiazol-4-yl)- and (1,2,3-thiadiazol-5-yl)imidazolidine-2,4-diones by cyclocondensation of the respective (1,2,3-thiadiazolyl)ureidoacetic acids were studied. The reactions were studied under the conditions of traditional heating at 140°C temperature and microwave irradiation at 170°C. It was shown that microwave heating of (1,2,3-thiadiazol-5-yl)ureido derivatives of carboxylic acids led to the formation of imidazolidine ring, unlike in the case of (1,2,3-thiadiazol-4-yl)ureido derivatives, for which traditional heating was more effective. The derivatives of (1,2,3-thiadiazolyl)imidazolidine-2,4-diones and (1,2,3-thiadiazolyl)ureidoacetic acids were studied with regard to their effects on pine seed germination and seedling growth.

SYNTHESIS AND CYTOTOXIC ACTIVITY OF 1,2,3-TRIAZOLE DERIVATIVES IN GLIOMA CELL CULTURES

A series of 1,2,3-triazole derivatives was prepared and their cytotoxic actions on glioma cell cultures were studied. Amethod for the synthesis of 1-R-5-methyl-1H-[1,2,3]triazole-4-carboxamides is presented, based on transformation of 4-acetyl-1-phenyl-1H-[1,2,3]-triazolate sodium using primary amine hydrochlorides.

Synthesis of spiro derivatives of 1,2,3-triazolo[5,1- b ][1,3,4]thiadiazines and biological activity thereof

3-Cyclopentylidene(cyclohexylidene)amino-3H-1,2,3-triazole-4-thiolates, formed via Dimroth rearrangement of 1,2,3-thiadiazolylhydrazones of cyclopentanone and cyclohexanone in the presence of triethylamine, reacted in situ with α-bromoacetophenones with the formation of spirocyclic 6,7-dihydro-5H-[1,2,3]triazolo[5,1-b][1,3,4]thiadiazines. The effect of the obtained compounds on the viability and proliferative activity of four lines of cell cultures was studied. The selective proliferative activity was determined.

Synthesis of fused 3-cyano- and 3-carbamoyl-1,2,3,4-tetrahydroquinolines

A reaction of 3-benzoyl-3-cyano-1,2,3,4-tetrahydroquinolines with hydrazine hydrate is accompanied by elimination of the benzoyl group. A hydration reaction of 3-cyano-1,2,3,4-tetrahydroquinolines leads to 3-carbamoyl-1,2,3,4-tetrahydroquinolines.

Reaction of 5-Hydrazono-1,2,3-thiadiazoles with Toluene and Xylene in the Presence of PCl5

The treatment of 5-hydrazono-1,2,3-thiadiazoles by phosphorus pentachloride in toluene or xylene leads to an anomalous Dimroth rearrangement and the reaction of the mercapto function formed with the methyl group of the solvent to give 5-benzylmercapto-1,2,3-triazole.

Synthesis of 4-(4-oxo-1,3-thiazolidin-2-ylidene)-pyrrolidine-2,3,5-triones

It was shown that 2-(1,3-thiazolidin-2-ylidene)acetamides can be used as 2-enamides in cyclocondensation reactions with oxalyl chloride, leading to the formation of new heterocyclic assemblies – 4-(4-oxo-1,3-thiazolidin-2-ylidene)pyrrolidine-2,3,5-triones in 50–88% yields.

Synthesis of 5-(pyrazol-1-yl)-1,2,3-thiadiazoles

A method is proposed for the synthesis of ethyl 5-(3-aryl-4-formyl-1H-pyrazol-1-yl)-1,2,3-thiadiazole-4-carboxylates by a reaction of acetophenone (4-ethoxycarbonyl-1,2,3-thiadiazol-5-yl)hydrazones with a Vilsmeier–Haack complex. The obtained heterocyclic assemblies provide interesting substrates for further modification and study of biological activity.