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Information × Registration Number 0224U033121, (0120U101532) , R & D reports Title Targeted development of some potentially bioactive systems based on the nitrogen-containing heterocycles popup.stage_title Цілеспрямоване конструювання потенційно біоактивних систем на основі нітрогеновмісних гетероциклів Head Bratenko Mykhailo K., Доктор хімічних наук Registration Date 18-12-2024 Organization Bukovinian State Medical University popup.description1 to create an effective synthesis strategy for obtaining new types of derivatives of the nitrogen-containing heterocycles and application of their chemical potential in development of new bioactive systems popup.description2  Methods for the preparation of some known ones have been improved and approaches to new 1,3-disubstituted pyrazoles functionalized in position 4 with aldimine, chloroimidoyl, amidoxime, and amidrazone groups have been developed, which has made them accessible and highly effective reagents for the construction of new heterocyclic ensembles. The reactivity of N-alkylimines of 4-pyrazolecarbaldehydes in cyclocondensation with thioglycolic, β-mercaptopropionic, and thiosalicylic acids was investigated, and it was shown that the processes involving thioglycolic acid proceed most easily. N-[(4-pyrazolyl)methylene]alkylamines have been found to react stereoselectively with succinic anhydride to form 2-(4-pyrazolyl)-5-oxo-3-pyrrolidinecarboxylic acids. Similar cyclocondensation with homophthalic anhydride leads to trans- and cis-3-(4-pyrazolyl)-1-oxotetrahydroisoquinoline-4-carboxylic acids. It has been established that N-methylimines of 4-pyrazolecarbaldehydes undergo a [3+2]-dipolar cycloaddition reaction with nitrilimines generated from ethyl esters of 2-arylhydrazino-2-chloroacetic acid to form ethyl esters of 1-aryl-5-(pyrazol-4-yl)-4,5-dihydro-1H-1,2,4-triazolecarboxylic acids. Instead, in the case of N-(2-hydroxy)ethylimines, tandem cyclization occurs, leading to a new heterocyclic system – 3-(pyrazol-4-yl)-1,2,4-triazolo[3,4-c][1,4]-oxazine. Convenient methods for the synthesis of 4-(4,5-diphenylimidazolyl-2)-pyrazole derivatives and 2-amino-4-pyrazole-4Н-1,3-oxazines have been developed, which are based on the use of some in situ generated 4-pyrazolimines in cyclocondensations with benzyl and phenylacetylene, respectively. It has been found that pyrazolyl-4-carboximidoyl chlorides react with trimethylsilyl azide to form 5-(4-pyrazolyl)tetrazoles. It has been shown that 4-pyrazolylamidoximes and 4-pyrazolylamidrazones are effective binucleophilic reagents for the synthesis of 3-(pyrazol-4-yl)-1,2,4-oxadiazole, -thiadiazole, and -triazole derivatives. Product Description popup.authors Barus Marianna M. Bratenko Mykhailo K. Velyka Alla Ya. Havrylyuk Olesya I. Alina M. Hrozav Deineka Sviatoslav Ye. Panasenko Nadiia V. Perepelitsa Olesia O. Chornous Vitalii O. Yakovychuk Nina D. popup.nrat_date 2024-12-18 Close