A new type of intramolecular cyclization of 1,5 bis[2 (E 3 oxo 3 phenylprop 1 enyl) phenoxy] 3 oxapentane with 3 aminotriazole promoted by potassium ions was discovered. A cascade mechanism for the formation of crownophane with 4,7 dihydro[1,2,4]triazolo[1,5 a] pyrimidine fragment was suggested. Effects of oligooxyethylene fragment of the chalcone podand and acid base catalysis on the selectivity of the cyclocondensation processes and degree of oxidation of triazolopyrimidine fragments were studied. The product structures were confirmed by IR, 1 H and 13 C NMR spectroscopy and X ray diffraction study.
A new type of template-assisted cyclization was found to occur in the course of nucleophilic reactions on chalcone podands, thus resulting in the formation of rather new complex polycyclic compounds. The structure of 25-methyl-23,29-diphenyl-8,11,14-trioxa-24-azahexa-cyclo[20.8.0.0 2,7 .0 15,20
A reaction of 3 (2 ethoxyphenyl) substituted chalcone with aminoazoles was studied. The nature of aza groups in aminoazoles was found to affect the regioselectivity of amination in the course of the formation of isomeric pyrazolo[3,4 b]pyridine, azolo[1,5 a] and [4,3 a] pyrimidine systems and the depth of the reaction were determined. A regulatory role of catalysts and solvents in the direction of the cascade reactions was established. Mechanisms of the reactions were suggested. A significance of the alkoxy substituent in chalcone for stereoselec tive synthesis of Michael adducts, including 3 (2 ethoxyphenyl) 3 (7 (2 ethoxyphenyl) 5 phenyl 6,7 dihydroazolopyrimidin 6 yl) 1 phenylpropan 1 ones, was demonstrated. The structures of products synthesized were established by 1 H and 13 C NMR spectroscopy and X ray diffraction analysis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.