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In this work, we considered the formation of supramolecular assemblies of melamine-thiobarbiturate and melamine-barbiturate-thiobarbiturate. It is known that thiobarbituric acid can form many tautomers, as well as different motifs due to the change of C2=O to C2=S hydrogen bonds. We formed the crystal. The resulting crystals were studied with scanning electron microscopy (SEM), optical fluorescence microscopy, single crystal and powder (PXRD) X-ray diffraction analyses, and solid state nuclear magnetic resonance (ss NMR). These systems were theoretically studied using density functional theory (DFT) and classical molecular dynamics (MD) simulations. Interestingly, just as in the case of melamine barbiturate, during the crystallization process, hydrogen from the C5 moiety of thiobarbituric acid migrates to the melamine molecule. In addition, the resulting melamine thiobarbiturate crystals exhibit fluorescence behavior in the red region (~565–605 nm), while the melamine barbiturate crystals are fluorescent in the green region (512–542 nm). [ABSTRACT FROM AUTHOR]

This article discusses the oxidation of methyl linoleate in micelles, initiated by the lipid‐soluble initiator 2,2′‐azobis (2,4‐dimethylvaleronitrile) (AMVN). It was shown that the rate constant (ki) is initiated in micelles for AMVN significantly lower than the known rate constant of initiation in true solutions. This can be explained by the reduced probability of AMVN radicals leaving the cage and an increase in the rate of chain termination between initiator radicals under conditions of low oxygen content. This conclusion was confirmed by quantum chemical calculations. Surprisingly, when determining the AMVN initiation rate constant for the consumption of nitroxyl radicals (>NO⋅), the ki depends on the concentration >NO⋅, this is due to the dependence of the probability of the nitroxyl radical and initiator radicals in micelles meeting on their concentration. Upon initiation of AMVN, no hydroperoxyl radical is expelled. [ABSTRACT FROM AUTHOR]