Thirteen isopropyl chalcones (CA1−CA13) were synthesized and evaluated for their inhibitory activity against monoamine oxidase (MAO). All compounds inhibited MAO-B more effectively than MAO-A. Compound CA4 most potently inhibited MAO-B with an IC 50 value of 0.032 μM, similar to that of CA3 (IC 50 = 0.035 μM) and with high selectivity index (SI) values for MAO-B over respectively). The −OH (CA4) or −F (CA3) group at the para position on the A ring provided higher MAO-B inhibition than that of the other substituents (−OH ≥ −F > −Cl > −Br > −OCH 2 CH 3 > −CF 3 ). On the other hand, compound CA10 most potently inhibited MAO-A with an IC 50 value of 0.310 μM and effectively MAO-B (IC 50 = 0.074 μM). The Br-containing thiophene substituent (CA10) instead of the A ring showed the highest MAO-A inhibition. In a kinetic study, K i values of compounds CA3 and CA4 for MAO-B were 0.076 ± 0.001 and 0.027 ± 0.002 μM, respectively, and that of CA10 for MAO-A was 0.016 ± 0.005 μM. A reversibility study showed that CA3 and CA4 were reversible inhibitors of MAO-B and CA10 was a reversible inhibitor of MAO-A. In docking and molecular dynamics, the hydroxyl group of CA4 and two hydrogen bonds contributed to the stability of the protein−ligand complex. These results suggest that CA3 and CA4 are potent reversible selective MAO-B inhibitors and can be used for the treatment of Parkinson's disease.

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The chiral separation of pharmaceutical molecules and their precursors is one of the important areas of application of HPLC in pharmaceutical analysis for obtaining enantiomerically pure drug. The latter procedures include the use of so-called chiral selectors to enantio-selectively recognise and isolate the enantiomer. The direct approaches, i.e. those which do not derivate the compound of interest before separation, are addressed in detail, since they are now the most common approaches. The role of stereochemistry in medicinal products is being given greater emphasis to medical practice. For physicians to make conscious choice about the use of single-enantiomered medicinal products, basic knowledge is required. For few treatments single-enantiomer formulations can provide more selectivity than a combination of enantiomers in their biological purposes, enhanced therapeutic indexes and/or better pharmacokinetics. This highlights the possible biological and pharmacological variations between the two drug enantiomers and underlines the clinical experience of individual enantiomers. Particular emphases have been put on chiral separation by HPLC on chiral stationary phases (CSPs). Chiral derivatization reagents (CDRs) are optically pure reagent on reaction with drugs forms a pair of diastereoisomers that can be separated on conventional achiral phase.  In Chiral mobile phase additive (CMPA) method, the stationary phase is achiral and the chiral selector is dissolved during the mobile phase. Interaction with the analyte’s enantiomer leads to the formation of transient diastereomeric complexes that are separated by their affinity towards mobile/stationary phase. Separation mechanisms and method development for chiral molecules using these phases are discussed in this review.

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In the preservation of normal physiological functions, the building blocks of the body called amino acids play a crucial role. A number of valuable and nutritional phytoconstituents are contained in fruit juices, such as vitamins, minerals, microelements, organic acids, antioxidants, flavonoids, amino acids and other components. Due to the growing population and demand, the quality of fruit juices is decreasing. One of the unethical and harmful practices called adulteration or food fraudulence has been adopted by most food and beverage industries. The amino acids which is one of the most important phytochemicals of fruit and fruit juices which affects the organoleptic properties like color, odor, and taste of juices and also helps in authenticity process from governing bodies by providing total amino acid content. Consequently, the main aim of the present review work is to provide information regarding the importance of amino acids, how they are adulterated, the potential analytical approach to detected amino acids and which methods are generally accepted method by the food industries. According to the literature review, we presume that reverse phased high-performance liquid chromatography with pre-column derivatization was the most adopted method for quality checking due to its advantages over other old and recent analytical approaches like simple, rapid, cost-effective nature, less / no sample matrix effect with high sensitivity, accuracy, and precision.