Multicomponent reactions are powerful synthetic tools for the efficient creation of complex organic molecules in an one-pot one-step fashion. Moreover, the amount of solvents and energy needed for separation and purification of intermediates is significantly reduced what is beneficial from the green chemistry issues point of view. This review highlights the development of multicomponent reactions conducted using aqueous micelles systems during the last two decades.

The biological research on newly synthesized amidoximes, Boc-protected amidoximes and Boc-derived amidines, obtained by a reduction of the parent amidoximes is reported, herein. Due to the presence of a free amino group in both amidines and amidoximes, these compounds can undergo various chemical reactions such as N-alkylation and N-acylation. One such reaction is Boc-protection, often used in organic synthesis to protect the amino and imino groups. Until now, Boc-protected amidoximes have not been tested for biological activity. Amidoxime derivatives were tested on bacterial E. coli strains. Initial cellular studies tests and digestion with Fpg after the modification of bacterial DNA, suggest that these compounds may have greater potential as antibacterial agents compared to antibiotics such as ciprofloxacin (ci), bleomycin (b) and cloxacillin (cl). The described compounds are highly specific for pathogenic E. coli strains on the basis of the model strains used and may be used in the future as new substitutes for commonly used antibiotics in clinical and hospital infections in the pandemic era.

Herein, we present biological studies on 3,4-dihydropyrimidin-2(1H)-ones (DHPMs) obtained via Biginelli reaction catalyzed by NH4Cl under solvent-free conditions. Until now, DHPMs have not been tested for biological activity against pathogenic E. coli strains. We tested 16 newly synthesized DHPMs as antimicrobial agents on model E. coli strains (K12 and R2–R4). Preliminary cellular studies using MIC and MBC tests and digestion of Fpg after modification of bacterial DNA suggest that these compounds may have greater potential as antibacterial agents than typically used antibiotics, such as ciprofloxacin (ci), bleomycin (b) and cloxacillin (cl). The described compounds are highly specific for pathogenic E. coli strains based on the model strains used and may be engaged in the future as new substitutes for commonly used antibiotics in clinical and nosocomial infections in the pandemic era.

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A tandem enzyme‐catalyzed Knoevenagel reaction with acetaldehyde is presented. A new protocol for the synthesis of the desired products through a tandem process based on the enzymatic hydrolysis and Knoevenagel reaction starting from acetaldehyde precursors is disclosed. The influence of the reaction conditions including organic solvent, enzyme type, and temperature on the reaction course was tested. Further, this protocol was extended by subsequent tandem chemoenzymatic transformations leading to epoxides.

In recent years, wheat germ lipase (WGL) is attracting considerable interest. To date, several WGL applications have already been described: (i) fats and oils modification; (ii) esterification reactions in organic media, accepting a wide range of acids and alcohols as substrates; (iii) the asymmetric resolution of various chiral racemic intermediates; (iv) more recently, the promiscuous activity of WGL has been shown in carbon-carbon bond formation. To date, no crystallographic structure of this enzyme has been published, which means its activity, catalytic potential and substrate scope is being assessed empirically. Therefore, new catalytic activities of this enzyme are constantly being discovered. Taking into account the emergency and the current interest in environmentally sustainable processes, this review aims to highlight the origin, isolation, stabilization by immobilization and applications of the wheat germ lipase. HIGHLIGHTSWheat germ as an inexpensive source of biocatalysts Wheat germ lipase an efficient catalyst for various chemical transformations Wheat germ lipase in food production Industrial applications of wheat germ lipase Wheat germ lipase as a promiscuous biocatalyst Immobilization of wheat germ lipase as a method of stabilization ARTICLE HISTORY

The novel and efficient approach toward the synthesis of endocyclic enol lactones was devised based on ring-closing metathesis of unsaturated carboxylic acids vinyl esters. Systematic studies revealed that vinyl esters are suitable substrates for RCM reaction. The developed methodology offers an easy route for synthetically challenging target molecules with different functional groups and substitution. We have also demonstrated that vinyl esters of cyclic carboxylic acids can be successfully applied for domino ring-opening ring-closing metathesis sequences.

The first example of dynamic kinetic resolution (DKR) of chiral unsaturated carboxylic acids is described. The application of tandem metal–enzyme DKR is a powerful tool for the manufacture of high-value chemical commodities. This new protocol of kinetic resolution based on irreversible enzymatic esterification of 3-aryl-4-pentenoic acids with ortho esters was introduced to obtain optically active unsaturated carboxylic acids. This procedure was combined with metal-catalyzed racemization of the target substrate, providing the optically pure S enantiomer of ethyl 3-phenylpent-4-enoate with very high isolated yield (98%). A substantial influence of organic cosolvent and metal catalyst on the conversion and enantioselectivity of the enzymatic dynamic kinetic resolution was noted.