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The synthetic cannabinoids 5F-QUPIC and MDMB-CHMICA were sprayed on plant material intended for smoking and was seized as a criminal evidence. Their presence was confirmed by gas chromatography – m...

The spectral properties of a tautomeric Schiff base containing aza-15-crown-5 moiety, namely N-((4-methylnaphthalen-1-yl)methylene)-4-(1,4,7,10-tetraoxa-13-azacyclopentadecan-13-yl)aniline on addition of alkali and alkaline earth metal ions were investigated. The newly synthesized ligand exhibited very interesting color changes in presence of metal ions: from yellow (free ligand) via colorlessness (enol tautomer complex) to yellow–orange (keto tautomer complex). These changes result from 2 stepwise processes: complex formation and shift of the tautomeric equilibrium between the tautomers after addition of the metal ions.

Avoiding trial and error experiments, the LSChrom software incorporating the Snyder theory was applied successfully to automatic selection of mobile phases for thin‐layer chromatography (TLC) on silica of two libraries of substituted trans‐piperidinones comprising amidolactames 1–15 and aminolactames 16–22. The procedure takes into account the adsorption properties of the mobile phase (parameter ϵ), stationary phase, and sample structure expressed by relevant groups. The recommended software value of ϵ was 0.460 for compounds 1–15 and 0.371 for compounds 16–22. Within about 190 measurements on silica using 13 computer selected mobile phases having these values of ϵ, the retention of any compound fell within a favorable range (0