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Stable palladium (II) complexes, incorporating a double (N-benzoylthiourea) arrangement bonded to a complex heterocyclic scaffold, are used as precursors of catalytic species able to promote Suzuki–Miyaura, Mizoroki–Heck, Hiyama, Buchwald–Hartwig, Hirao and Sonogashira–Hagihara cross-coupling transformations in water. These sustainable processes are chemoselective and very versatile. The nanoparticles responsible for these catalytic reactions were analyzed and studied. Their usefulness is demonstrated after several tests and analyses. The heterogeneous character of this species in water was also confirmed.

To overcome numerous health disorders, heterocyclic structures of synthetic or natural origin are utilized, and notably, the emergence of various side effects of existing drugs used for treatment or the resistance of disease-causing microorganisms renders drugs ineffective. Therefore, the discovery of potential therapeutic agents that utilize different modes of action is of utmost significance to circumvent these constraints. Pyrrolidines, pyrrolidine-alkaloids, and pyrrolidine-based hybrid molecules are present in many natural products and pharmacologically important agents. Their key roles in pharmacotherapy make them a versatile scaffold for designing and developing novel biologically active compounds and drug candidates. This review aims to provide an overview of recent advancements (especially during 2015–2023) in the exploration of pyrrolidine derivatives, emphasizing their significance as fundamental components of the skeletal structure. In contrast to previous reviews that have predominantly focused on a singular biological activity associated with these molecules, this review consolidates findings from various investigations encompassing a wide range of important activities (antimicrobial, antiviral, anticancer, anti-inflammatory, anticonvulsant, cholinesterase inhibition, and carbonic anhydrase inhibition) exhibited by pyrrolidine derivatives. This study is also anticipated to serve as a valuable resource for drug research and development endeavors, offering significant insights and guidance.

The synthesis of 4-arylthiazol-2(3H)-ones is reported employing a novel and mild methodology using benign solvents. In a second objective the multicomponent preparation of 5,5’-methylenebis[4-arylthiazol-2(3H)-ones] is described following the same strategy. The analysis of the mechanism is also studied and confirmed using chemical tests.

A series of novel N-benzoylthiourea-pyrrolidine carboxylic acid derivatives bearing an imidazole moiety has been prepared and their various biological activities are evaluated. The ability of forming intermolecular hydrogen-bonds of these molecules was pursued in the search of the best antimicrobial activity. The synthesized compounds were tested to search whether they had an enzyme inhibitory potency against AChE and BChE, which are the main targets for Alzheimer's disease. The prepared compounds were also screened for antituberculosis activity against M. tuberculosis H37Rv strain and the antibacterial activity against E. coli, A. baumannii, S. aureus, B. subtilis, A. hydrophila, bacteria. In addition, their antifungal activities are also evaluated against C. tropicalis, C. albicans, C. glabrata strains.

A series of novel palladium(II) and nickel(II) complexes of multifunctionalized aroylaminocarbo-N-thioylpyrrolinates were synthesized and characterized by analytical and spectroscopic techniques. The biological properties of the freshly prepared compounds were screened against S. aureus, B. subtilis, A. hydrophila, E. coli, and A. baumannii bacteria and antituberculosis activity against M. tuberculosis H37Rv strains. Also, the antifungal activity was studied against C. albicans, C. tropicalis, and C. glabrata standard strains. A deep conformational survey was monitored using DFT calculations with the aim to explain the importance of the final conformation in the biological experimental results.

Homocoupling reactions promoted by photocatalysts are not very abundant in the literature. However, the products generated from such processes are very interesting. In this review, we highlight the most relevant reports concerning photocatalyzed dimerizations covering the literature until the middle of 2020. Reactions will be classified according to the type of starting material employed, with an emphasis being placed on the corresponding mechanism.

The Suzuki-Miyaura cross-coupling reaction using 4-amino-1,2,4-triazoles and 1,3,4-oxadiazoles-2-thiones·palladium (II) is studied. The reaction is optimized and the most appropriate catalytic complex is tested with several aryl halides, boronic acids in an environmentally benign solvent system (H2O/EtOH). The recovery of the catalytic species is also surveyed because of the nature of the employed solvent. A domino process is efficiently carried out following the standard conditions. Several surface parameters of the ligands are analyzed and the resulting values are extrapolated to the insoluble palladium catalyst.

The synthesis of a mononuclear octahedral [Prolinate2-Na(MeOH)4]−H+ complex is achieved from a [3 + 2] cycloadduct with excess of NaOMe in methanol. The slow crystallization provides the hexacoordinated complex stabilized by four molecules of solvent. The antibacterial, antifungal and anti-tuberculosis activity of this compound is also evaluated.

Platinum complexes, derived from two families of bidentate funcionalized aroylaminocarbo-N-thyoyl prolinates, are prepared using mild conditions from prolinates, which are available via 1,3-dipolar cycloadditions. The resulting four coordinated neutral square-planar platinum(II) complexes are very stable and are fully characterized. Their structures are determined by spectroscopic and analytical methods and one of them by single crystal X-ray diffraction analysis. In this pattern, the platinum exhibits distorted square planar geometry, with cis-bond angles ranging from 89.42(2) and 94.37(6)° and trans-bond angles of 176.19(6) and 177.08(6)°, respectively. Anti(myco)bacterial and antifungal studies of all these new compounds are carried out under standardized protocols.

The chemistry of palladium complexes has no limits. Many domino processes (even multicomponent) are continuously appearing in the literature. Carbocyclic and heterocyclic molecules are efficiently prepared under the atom-economy principle using the smallest amount of the catalyst. The importance of the applications in many scientific areas of all of these cyclic skeletons made this general methodology much more attractive.

The process involving a rearrangement of pyrrolidino[3,4-c]pyrrolidine to another pyrrolidino[3,4-b]pyrrolidine using sodium methoxide as base is fully studied. The effects of the substituents are analyzed during the ring-opening/ring-closing sequence. Computational studies are also performed to explain the importance of susbstituents and quaternary carbons, especially when the (3-indolyl)methyl is present in the starting material. Finally, all the samples are evaluated as potential candidates for antibacterial and antimycobacterial activities.

A series of prolinate and N-amidocarbothiolprolinate derivatives based on a fused pyrrole-3,4-dione core, bearing indole ring systems, are prepared from the corresponding amino acid and an aldehyde via thermal 1,3-dipolar cycloaddition of azomethine ylides and condensation with benzoylisothiocyanate. Products are fully characterized by NMR, FT-IR, MS, and an X-ray crystal structure. The prepared compounds are screened for their antibacterial activity against a range of Gram-positive and Gram-negative bacteria and their antimycobacterial activity against M. tuberculosis H37Rv strain. In addition, two selected target compounds are evaluated for cytotoxicity, apoptosis, and anti-inflammatory effects on MCF-7 (breast carcinoma) cell lines. The incorporation of indole ring and –C(O)NHC(S)– moiety resulted to be beneficial since the biological point of view.

Structurally diverse novel 1,4-benzodiazepine analogues related to selective CCKA antagonist MK-329, and CCKB antagonists L-365,260 and YM022 are prepared via palladium-catalyzed three component domino reactions involving allenylation-carbonylation-anion capture in one-pot cascade protocol in good to excellent yields.

A versatile, facile and concise approach to access to highly substituted functionalized 2-(pyrrolidin-1-yl)thiazole ring system is accomplished. The efficient protocol proceeds by the reaction of corresponding racemic or enantiomerically enriched pyrrolidines and readily available benzoylisothiocyanate in acetonitrile followed by sequential reaction of readily available alpha-bromo ketones in acetone. The selectivity and good yield in the desired product is another important advantage of this reaction protocol. In a few cases, the resulting N-benzoylthiourea intermediate cyclizes spontaneously before reacting with the benzophenone component. Finally, a wide study of the biological scope of this new bisheterocyclic molecules is reported.

This review summarizes the trends in the formation of complex or not so complex heterocyclic structures through 1,3-dipolar cy­cloadditions of azomethine ylides. Diastereo- and enantioselective processes as well as non-asymmetric cycloadditions constitute very important synthetic tools for achieving these compounds. This review covers the literature from 2015 through 2016 and organizes the research in terms of biologically important heterocycles and natural products from cascade 1,3-dipolar cycloadditions of azomethine ylides to the simpler forms of 1,3-dipolar cycloaddition.