Chiral HPLC separation and simulation studies of two chiral centered bis-imino flavans (Schiff base)

Enantiomeric separation of thiourea derivatives of naringenin on amylose and cellulose polymeric chromatographic chiral columns

Due to a great demand for amylose and cellulose polymeric chromatographic chiral columns, the enantiomeric separation of thiourea derivatives of naringenin was achieved on the different amylose (Chiralpak-IB) and cellulose chiral (Chiralcel-OJ and Chiralcel-OD-3R) columns with varied chromatographic conditions. The isocratic mobile phases used were ethanol and methanol, where ethanol/hexane and methanol/hexane were used as gradient mode and were prepared in volume/volume relation. The separation and resolution factors for all the enantiomers were in the range of 1.25 to 3.47 and 0.48 to 1.75, respectively. The enantiomeric resolution was obtained within 12 min making fast separation. The docking studies confirmed the chiral recognition mechanisms with binding affinities in the range of -4.7 to -5.7 kcal/mol. The reported compounds have good anticoagulant activities and may be used as anticoagulants in the future. Besides, chiral separation is fast and is useful for enantiomeric separation in any laboratory in the world.

Biomimetic Self-Assembled Chiral Inorganic Nanomaterials: A New Strategy for Solving Medical Problems

The rapid expansion of the study of chiral inorganic structures has led to the extension of the functional boundaries of inorganic materials. Nature-inspired self-assembled chiral inorganic structures exhibit diverse morphologies due to their high assembly efficiency and controlled assembly process, and they exhibit superior inherent properties such as mechanical properties, chiral optical activity, and chiral fluorescence. Although chiral self-assembled inorganic structures are becoming more mature in chiral catalysis and chiral optical regulation, biomedical research is still in its infancy. In this paper, various forms of chiral self-assembled inorganic structures are summarized, which provides a structural starting point for various applications of chiral self-assembly inorganic structures in biomedical fields. Based on the few existing research statuses and mechanism discussions on the chiral self-assembled materials-mediated regulation of cell behavior, molecular probes, and tumor therapy, this paper provides guidance for future chiral self-assembled structures to solve the same or similar medical problems. In the field of chiral photonics, chiral self-assembled structures exhibit a chirality-induced selection effect, while selectivity is exhibited by chiral isomers in the medical field. It is worth considering whether there is some correspondence or juxtaposition between these phenomena. Future chiral self-assembled structures in medicine will focus on the precise treatment of tumors, induction of soft and hard tissue regeneration, explanation of the biochemical mechanisms and processes of its medical effects, and improvement of related theories.

Rapid chiral separation of potential antibiotics using supercritical fluid chromatography

WHO is searching most active antibiotics due to the bacterial resistance problem. The activities of the racemic antibiotics may be augment by preparing optically active antibiotics by the chiral separation. Chiral separation of potential antibiotics such as cefotaxime and ofloxacin was studied using amylose-based packing chiral stationary phases (CSPs) such as Chiralpak IA and Chiralpak IG. Supercritical fluid chromatography (SFC) was employed to carry out this study. Both immobilized CSPs such as Chiralpak IA and IG have sown remarkable selectivity for the reported drugs by using SFC. The values of retention factor (k) for ofloxacin enantiomers were 9.63 and 11.81, followed by 2.94 and 5.96 for cefotaxime enantiomers. The values of separation factor (α) for both the reported drugs were 1.22 and 2.03, respectively Similarly, the values of resolution factor (Rs) for both the enantio-selective drugs were 1.49 and 2.06, separately and respectively. The chiral recognition mechanism was developed and it was observed that the π-π interactions are playing a major role. The developed method is effective, reproducible, eco-friendly, and may be used to discriminate the enantiomers of the reported drugs in any sample.