Expanding cyclodextrin use in normal phase and super/subcritical fluid chromatographic modes for the chiral separation of 1,4-dihydropyridines.

Cyclodextrin-based stationary phases are important chiral selectors in liquid chromatography. These chiral selectors are most commonly used in the reversed-phase mode because native cyclodextrin assumes a torus conformation with a hydrophobic cavity, facilitating inclusion complexation in aqueous environments. However, the value of native and aliphatic-derivatized cyclodextrins in other modes, such as the normal phase liquid chromatography (NPLC) or super/subcritical fluid chromatography (SFC), remains unexplored.

Chiral superficially porous stationary phases for enantiomeric separation of condensed 1,4-dihydropyridine derivatives.

1,4-dihydropyridine (DHP) scaffold occupies a prominent position among all heterocyclic compounds owing to its versatile pharmacological properties, particularly its well-known calcium channel blocking activity. In the quest of developing new calcium channel blockers, fifty seven 5-oxo-hexahydroquinoline (HHQ) derivatives carrying DHP framework in a condensed ring system were recently synthesized as racemic mixtures. Due to their potential as drug candidates, enantiomers arising from the asymmetric center at the C-4 position of the HHQ ring were separated.

Solving Advanced Task-Specific Problems in Measurement Sciences with Generative AI.

The Generative Pre-Trained Transformer known as ChatGPT-4 has undergone extensive pretraining on a diverse data set, enabling it to generate coherent and contextually relevant text based on the input it receives. This capability allows it to perform tasks from answering questions and has attracted significant interest in material sciences, synthetic chemistry, and drug discovery. In this work, we posed four advanced task-specific problems to ChatGPT, which were recently published in leading journals for topics in analytical chemistry, spectroscopy, bioimage super-resolution, and electrochemistry.

Influence of theoretical and semi-empirical peak models on the efficiency calculation in chiral chromatography.

Height equivalent to theoretical plate (H) equations, such as the van Deemter or Knox-Saleem equations, and other efficiency vs. linear velocity equations (u), provide kinetic insights into chromatographic separations phenomena and column performance. In enantioselective separations, the peak shape of the two enantiomers can differ significantly and are often asymmetric.