Multicomponent Reaction

In eukaryotic cells, molecular fate and cellular responses are shaped by multicomponent enzyme systems which reversibly attach ubiquitin and ubiquitin-like modifiers to target proteins. The extent of the ubiquitin proteasome system in Leishmania mexicana and its importance for parasite survival has recently been established through deletion mutagenesis and life-cycle phenotyping studies. The ubiquitin conjugating E2 enzyme UBC2, and the E2 enzyme variant UEV1, with which it forms a stable complex in vitro, were shown to be essential for the differentiation of promastigote parasites to the infectious amastigote form...

The stereodefined and highly substituted vinylsilanes are essential building blocks for constructing complex organic molecules. Transition metal-mediated silylmetalation of alkynes was developed to overcome the limitations of conventional hydrosilylations; however, a very limited study was carried out to utilize transient vinylmetal species in cross-coupling reactions. Moreover, they produce syn-adduct, and the anti-selective cross-coupling is still unknown and highly desired. Silylzinc reagents are highly functional group tolerant, however, their synthesis from pyrophoric silyllithium and dissolved lithium salts hampers cross-coupling reactions...

In this study, arylglyoxals, acetylacetone, and 2,6-dimethyl phenol or 2,6-di-tert-butyl phenol are combined to efficiently synthesize a series of 1-(4-(3,5-dialkylphenyl)-2-methyl-5-phenylfuran-3-yl) ethan-1-one derivatives in excellent yields. These reactions were carried out in acetone at reflux under catalyst-free conditions in the presence of triethylamine as a base for 3 h. NMR, FT-IR, EI-MS, and elemental studies were used to characterize the products' structural characteristics. The present study has also several benefits, such as excellent yields and the ease of workup procedure, making it an appealing, practical, and acceptable one-pot method for producing functionalized derivatives of dialkyl furan...

Ursodeoxycholic acid (UDCA) and acetoacetate are natural compounds present in the human intestine and blood, respectively. A number of studies highlighted that besides their well-known primary biological roles, both compounds possess the ability to influence a variety of cellular processes involved in the etiology of various diseases. These reasons suggested the potential of acetoacetate-UDCA hybrids as possible therapeutic agents and prompted us to develop a synthetic strategy to selectively derivatize the hydroxyl groups of the bile acid with acetoacetyl moieties...

There is an increasing concern about the presence of various types of pharmaceuticals in drinking water, as long-term exposure of people to even low concentrations of drugs can lead to many problems, such as endocrine disorders or drug resistance. As the removal in sewage treatment plants is not effective enough, as indicated, among others, by the EC and OECD reports, it is justified to search for new materials that will allow for an effective and rapid reduction of these pollutants in water. Therefore, in our work, catalytically active nanomaterials containing platinum group metals (PGMs) were synthesized from model and real multicomponent solutions and examined in reactions of organic compounds...

One well-known multicomponent reaction that is helpful in the synthesis of dihydropyrimidinones (DHPMs), important molecules in organic synthesis and medicinal chemistry, is the Biginelli reaction. Because of their wide range of biological activities, DHPMs are regarded as essential chemicals. A great deal of research has been done in the last few decades to find ways to produce enantiomerically pure DHPMs because of their notable and focused target-oriented biological activities. In this reaction, numerous structural variants and catalysts have been employed in a range of solvents to yield an enormous number of Biginelli-type compounds...

A straightforward route to 1,4-dihydropyrrolo[3,2- b ]pyrroles comprised of two electron-withdrawing quinoline or tetrazolo[1,5- a ]quinoline scaffolds has been developed. The versatile multicomponent reaction affording 1,4-dihydropyrrolo[3,2- b ]pyrroles combined with intramolecular direct arylation enables assembly of these products in just three steps from anilines with overall yields exceeding 30%. The planarized, ladder-type heteroacenes possess up to 14 conjugated rings. These nominally quadrupolar materials exhibit efficient fluorescence with wavelengths spanning most of the visible spectrum from green-yellow for the dyes possessing biaryl bridges and orange-red for the fully fused systems...

BACKGROUND: Multicomponent reactions are highly useful in synthesizing natural products and bioactive molecules. Out of several MCRs, although utilized widely, some remain neglected in review articles. The Gewald and Groebke-Blackburn-Bienaymé (GBB) reactions are two such reactions. This comprehensive review assimilates applications of Gewald and Groebke-Blackburn- Bienayme reactions in synthesizing novel antimicrobial agents. It presents the antimicrobial properties of the synthesized molecules, providing an overview of their potential druggability...

Solid oxide fuel cells that operate at intermediate temperatures require efficient catalysts to enhance the inherently poor electrochemical activity of the composite electrodes. Here, we present a simple and practical electrochemical deposition method for fabricating a PrOx overlayer on lanthanum strontium manganite-yttria-stabilized zirconia (LSM-YSZ) composite electrodes. The method requires less than four minutes for completion and can be carried out under at ambient temperature and pressure. Crucially, the treatment significantly improves the electrode's performance without requiring heat treatment or other supplementary processes...

Charting the chemical reaction space around the combination of carbonyls, amines, and isocyanoacetates allows the description of new multicomponent processes leading to a variety of unsaturated imidazolone scaffolds. The resulting compounds display the chromophore of the green fluorescent protein and the core of the natural product coelenterazine. Despite the competitive nature of the pathways involved, general protocols provide selective access to the desired chemotypes. Moreover, we describe unprecedented reactivity at the C-2 position of the imidazolone core to directly afford C, S, and N-derivatives featuring natural products (e...

Despite their significant importance to numerous fields, the difficulties in direct and diverse synthesis of α-hydroxy-γ-lactams pose substantial obstacles to their practical applications. Here, we designed a nitrogen and TiO2 co-doped graphitic carbon-supported material with atomically dispersed cobalt sites (CoSA -N/NC-TiO2 ), which was successfully applied as a multifunctional catalyst to establish a general method for direct construction of α-hydroxy-γ-lactams from cheap and abundant nitro(hetero)arenes, aldehydes, and H2 O with alkynoates...

Multicomponent reactions offer efficient and environmentally friendly strategies for preparing monoliths suitable for applications in analytical chemistry. In the described study, a multicomponent reaction was utilized for the one-pot miniaturized preparation of a poly(propargyl amine) polymer inside commercial silica-lined PEEK tubing. The reaction involved only small amounts of reagents and was characterized by atom economy. The resulting monolithic column was incorporated into an autosampler system for the online extraction and cleanup of β-estradiol from human serum...

Numerous studies in the field of alkaloid chemistry have provided researchers with valuable insights into their unique properties as catalysts. Among the diverse natural catalysts, caffeine has emerged as a green, expedient, and biodegradable catalyst with high efficiency and applicability. Interest in using caffeine as a catalyst has burgeoned over the past few years with its role in diverse multicomponent reactions. Preparation of its imidazolium salts and further conversion to Nitrogen Heterocyclic Carbene (NHC) ligands and ionic liquids offers new paradigms...

We present an Ugi multicomponent approach to explore the chemical space around Aspidosperma-type monoterpene indole alkaloids. By variation of the isocyanide and carboxylic acid inputs we demonstrate the rapid generation of molecular diversity and the possibility to introduce handles for further modification. The key Ugi three-component reaction showed full diastereoselectivity towards the cis-fused ring system, which can be rationalized by DFT calculations.  Moreover indicating that the reaction proceeds via a Passerini-type hydrogen bonding mechanism...

Quorum-sensing (QS) is a cell density-dependent signaling pathway regulated by gene expression for intra- and interspecies communication. We have targeted QS activity in Pseudomonas aeruginosa, an opportunistic human pathogen that causes disease in immunocompromised patients, with a set of probes containing a variety of functional groups, including photoreactive (diazirine) and affinity (alkyne) moieties, that were synthesized using a four-component Ugi reaction (Ugi-4CR).

Reaction of 2-chloromethylbenzimidazole with known intermediates (i - iii), prepared from diaminoguanidine hydrochloride with salicylaldehyde, 5-bromo-salicylaldehyde or 3,5-di-tert-butylsalicylaldehyde, led to the formation of benzimidazole appended new ligands, H4L1-H4L3 (I-III). The homogeneous nitrogen-bridged symmetrical binuclear complexes, [(MoVIO2)2(L1)(H2O)2] (1), [(MoVIO2)2(L2)(H2O)2] (2) and [(MoVIO2)2(L3)(MeOH)2] (3) and mononuclear complexes, [MoVIO2(H2L1)(MeOH)] (4), [MoVIO2(H2L2)(H2O)] (5) and [MoVIO2(H2L3)(MeOH)] (6)...

Methods for the synthesis of α-branched alkylamines are important due to their ubiquity in biologically active molecules. Despite the development of many methods for amine preparation, C(sp3 )-rich nitrogen-containing compounds continue to pose challenges for synthesis. While carbonyl reductive amination (CRA) between ketones and alkylamines is the cornerstone method for α-branched alkylamine synthesis, it is sometimes limited by the sterically demanding condensation step between dialkyl ketones and amines and the more restricted availability of ketones compared to aldehydes...

Heavy metal pollution treatment in industrial wastewater is crucial for protecting biological and environmental safety. However, the highly efficient and selective removal of heavy metal ions from multiple cations in wastewater is a significant challenge. This work proposed a pulse electrochemical method with a low-/high-voltage periodic appearance to selectively recover heavy metal ions from complex wastewater. It exhibited a higher recovery efficiency for heavy metal ions (100% for Pb2+ and Cd2+ , >98% for Mn2+ ) than other alkali and alkaline earth metal ions (Na+ , Ca2+ , and Mg2+ were kept below 3...

The development of one-pot, atom, and step-economic new methods avoiding metal, harsh reaction conditions, and toxic reagents for the synthesis of medicinally important hybrid molecules bearing more than one bioactive moieties is currently one of the hot topics in organic synthesis. Herein, we report a green and efficient room temperature multicomponent reaction for the synthesis of novel pyrazole-linked thiazoles involving a one-pot C-C, C-N, and C-S bond-forming process from the reaction of aryl glyoxal, aryl thioamide, and pyrazolones in 1,1,1,3,3,3-hexafluoroisopropanol, a hydrogen bond donating reaction medium...

Multiphase reactive flow in porous media is an important research topic in many natural and industrial processes. In the present work, photolithography is adopted to fabricate multicomponent mineral porous media in a microchannel, microfluidics experiments are conducted to capture the multiphase reactive flow, methyl violet 2B is employed to visualize the real-time concentration field of the acid solution and a sophisticated image processing method is developed to obtain the quantitative results of the distribution of different phases...