Multicomponent Assembly of Bicyclic Aza-peroxides Catalyzed by Samarium Complexes and Their Cytotoxic Activity.

An original strategy toward bridged tetraoxazaspirobicycloalkanes was developed. The synthesis is based on a three-component condensation-cyclization reaction of primary arylamines with 1,1'-peroxybis (1-hydroperoxycycloalkanes) and pentane-1,5-dial catalyzed by Sm(NO3)3·6H2O. The structures and conformations of the products were determined by X-ray diffraction analysis and 1H and 13C NMR spectroscopy. High cytotoxic activity and biological potential toward ferroptosis induction were found for the synthesized bicyclic aza-peroxides.

Catalyzed ring transformation of cyclic N-aryl-azadiperoxides with participation of α,ω-dithiols.

Co(OAc)2-catalyzed ring transformation reaction of 10-aryl-7,8,12,13-tetraoxa-10-azaspiro[5.7]tridecanes with α,ω-dithiols (ethane-1,2-, propane-1,3-, butane-1,4-, pentane-1,5-, and hexane-1,6-dithiols, 3,6-dioxaoctane-1,8-dithiol) giving 3-aryl-1,5,3-dithiazacyclanes was studied.

How the oxazole fragment influences the conformation of the tetraoxazocane ring in a cyclohexanespiro-3'-(1,2,4,5,7-tetraoxazocane): single-crystal X-ray and theoretical study.

Single crystals of (2S,5R)-2-isopropyl-5-methyl-7-(5-methylisoxazol-3-yl)cyclohexanespiro-3'-(1,2,4,5,7-tetraoxazocane), C16H26N2O5, have been studied via X-ray diffraction. The tetraoxazocane ring adopts a boat-chair conformation in the crystalline state, which is due to intramolecular interactions. Conformational analysis of the tetraoxazocane fragment performed at the B3LYP/6-31G(d,2p) level of theory showed that there are three minima on the potential energy surface, one of which corresponds to the conformation realized in the solid state, but not to a global minimum. Analysis of the geometry and the topological parameters of the electron density at the (3,-1) bond critical points (BCPs), and the charge transfer in the tetraoxazocane ring indicated that there are stereoelectronic effects in the O-C-O and N-C-O fragments. There is a two-cross hyperconjugation in the N-C-O fragment between the lone electron pair of the N atom (lpN) and the antibonding orbital of a C-O bond (σ*C-O) and vice versa between lpO and σ*C-N. The oxazole substituent has a considerable effect on the geometry and the topological parameters of the electron density at the (3,-1) BCPs of the tetraoxazocane ring. The crystal structure is stabilized via intermolecular C-H...N and C-H...O hydrogen bonds, which is unambiguously confirmed with PIXEL calculations, a quantum theory of atoms in molecules (QTAIM) topological analysis of the electron density at the (3,-1) BCPs and a Hirshfeld analysis of the electrostatic potential. The molecules form zigzag chains in the crystal due to intermolecular C-H...N interactions being electrostatic in origin. The molecules are further stacked due to C-H...O hydrogen bonds. The dispersion component in the total stabilization energy of the crystal lattice is 68.09%.

Synthesis and anticancer activity novel dimeric azatriperoxides.

An efficient method was developed for the synthesis of tetra(spirocycloalkane)-substituted α,ω-di(1,2,4,5,7,8-hexaoxa-10-azacycloundecan-10-yl)alkanes by a ring transformation reaction of 3,6-di(spirocycloalkane)-substituted 1,2,4,5,7,8,10-heptaoxacycloundecanes with α,ω-alkanediamines (1,4-butane-, 1,5-pentane-, 1,7-heptane-, 1,8-octane- and 1,10-decanediamines) catalyzed by Sm(NO3)3/γ-Al2O3. Using flow cytometry, it was shown for the first time that synthesized dimeric azatriperoxides are efficient apoptosis inducers with Jurkat, K562, U937, and Hek296.

New synthesis of tetraoxaspirododecane-diamines and tetraoxazaspirobicycloalkanes.

An efficient method for the synthesis of new spiro-tetraoxadodecanediamines and tetraoxazaspirobicycloalkanes has been developed by reactions of primary arylamines with gem-dihydroperoxides and α,ω-dialdehydes (glyoxal, pentanedial) catalyzed by lanthanide catalysts. A potential pathway for formation of tetraoxaspirododecane-diamines and tetraoxazospirobicycloalkanes has been proposed that involves generation of intermediate tetraoxaspiroalkanediols under the reaction conditions. The structures of the crystalline products have been confirmed by XRD. It was shown that the synthesized tetraoxazaspirobicycloalkanes exhibit high cytotoxic activity against Jurkat, K562, and U937 tumor cultures and Fibroblasts.