Recent advances in microwave-assisted multicomponent synthesis of spiro heterocycles.

Spiro heterocycle frameworks are a class of organic compounds that possesses unique structural features making them highly sought-after targets in drug discovery due to their diverse biological and pharmacological activities. Microwave-assisted organic synthesis has emerged as a powerful tool for assembling complex molecular architectures. The use of microwave irradiation in synthetic chemistry is a promising method for accelerating reaction rates and improving yields. This review provides insights into the current state of the art and highlights the potential of microwave-assisted multicomponent reactions in the synthesis of novel spiro heterocyclic compounds that were reported between 2017 and 2023.

Copper-catalyzed multicomponent reaction of ß-trifluoromethyl ß-diazo esters enabling the synthesis of ß-trifluoromethyl N,N-diacyl-ß-amino esters.

An efficient multicomponent reaction of newly designed ß-trifluoromethyl ß-diazo esters, acetonitrile, and carboxylic acids via an interrupted esterification process under copper-catalyzed conditions has been developed, which affords various unsymmetrical ß-trifluoromethyl N,N-diacyl-ß-amino esters in good to excellent yields. The reaction features mild conditions, a wide scope of ß-amino esters and carboxylic acids, and also applicability to large-scale synthesis, thus providing an efficient way for the synthesis of ß-trifluoromethyl ß-diacylamino esters. Furthermore, this reaction represents the first example of a Mumm rearrangement of ß-trifluoromethyl ß-diazo esters.

Recent developments using malononitrile in ultrasound-assisted multicomponent synthesis of heterocycles.

Ultrasonic irradiation serves as a vigorous and environmentally sustainable approach for augmenting multicomponent reactions (MCRs), offering benefits such as thermal enhancement, agitation, and activation, among others. Malononitrile emerges as a versatile reagent in this context, participating in a myriad of MCRs to produce structurally diverse heterocyclic frameworks. This review encapsulates the critical role of malononitrile in the sonochemical multicomponent synthesis of these heterocyclic structures. The paper further delves into the biochemical and pharmacological implications of these heterocycles, elucidating their reaction mechanisms as well as delineating the method's scope and limitations. We furnish an overview of the merits and challenges inherent to this synthetic approach and offer insights for potential avenues in future research.

Latest developments in coumarin-based anticancer agents: mechanism of action and structure-activity relationship studies.

Many researchers around the world are working on the development of novel anticancer drugs with different mechanisms of action. In this case, coumarin is a highly promising pharmacophore for the development of novel anticancer drugs. Besides, the hybridization of this moiety with other anticancer pharmacophores has emerged as a potent breakthrough in the treatment of cancer to decrease its side effects and increase its efficiency. This review aims to provide a comprehensive overview of the recent development of coumarin derivatives and their application as novel anticancer drugs. Herein, we highlight and describe the largest number of research works reported in this field from 2015 to August 2023, along with their mechanisms of action and structure-activity relationship studies, making this review different from the other review articles published on this topic to date.

Recent advances in the multicomponent synthesis of heterocycles using tetronic acid.

Tetronic acid, a versatile synthon, has been extensively investigated by numerous researchers in synthetic chemistry due to its crucial role in synthesizing heterocycles which makes this compound particularly advantageous in both pharmaceutical and biological fields. Various heterocycles can be synthesized using it as a precursor via multicomponent reactions (MCRs). Dicarbonyl groups can be considered the building blocks and key structural motifs of a wide range of natural compounds, which may contain different functional groups in the synthesis of heterocyclic frameworks. This review covers the literature from 2017 to 2022, and it encompasses the different one-pot protocols for synthesizing a variety of heterocyclic molecules.

Application of phenacyl bromide analogs as a versatile organic intermediate for the synthesis of heterocyclic compounds via multicomponent reactions.

Due to the increased interest in heterocyclic compounds over the past decade, many pharmaceutical and organic chemists have explored the synthesis of various materials. Among the many organic compounds that can be synthesized in a wide range of chemical reactions, phenacyl bromide has proven to be a good, inexpensive, versatile, and efficient intermediate. This review presents an overview of the significant applications of phenacyl bromide, focusing on its role in recent synthetic advances and its utility in multicomponent reactions and literature reports for 2017 to the end of 2021.

One-pot synthesis of 2-amino-4H-chromene derivatives by MNPs@Cu as an effective and reusable magnetic nanocatalyst.

In this research, MNPs@Cu as an effective and recyclable nanocatalyst was prepared and characterized using different methods including Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). After the characterization of this new nanocatalyst, it was efficiently used for the promotion of the one-pot synthesis of 2-amino-4H-chromene derivatives via one-pot three-component reaction of the enolizable compound, malononitrile, and arylaldehydes under solvent-free conditions at 90 °C. The procedure gave the desired products in high-to-excellent yields in short reaction times. Also this catalyst, because of its magnetic nature, can be simply restored by a permanent magnetic field and comfortably reused several times without any significant loss of its catalytic activity.

A Surfactant Directed Microcrystalline Cellulose/Polyaniline Composite with Enhanced Electrochemical Properties.

In this study a cationic surfactant, cetyltrimethylammonium bromide (CTAB), was used as a soft template for in situ chemical polymerization of aniline on the surface of microcrystalline cellulose (MCC). The morphology of the wire-like and porous nanostructure of the resulting composite was highly dependent on the MCC and CTAB concentrations. The effect of the MCC and CTAB concentrations on the electrochemical and morphological properties of the polyaniline (PAni) nanocomposite was studied. Cyclic voltammograms of modified PAni/MCC/CTAB electrode displayed a high current response and the effect of scan rate on the current response confirmed a diffusion controlled process on the surface of the electrode that makes it suitable for sensor applications. The overlapping characteristic peaks of pure PAni and MCC caused peak broadening at 3263 cm-1 in the IR spectra of PAni/MCC/CTAB nanocomposite that revealed the interaction between NH of PAni and OH group of MCC via electrostatic interactions. The addition of MCC to PAni through chemical polymerization decreased the thermal stability of composite compared to pure PAni. Lower crystallinity was observed in the XRD diffractogram, with 2 theta values of 22.8, 16.5, and 34.6 for PAni/MCC, confirming the formation of PAni on the MCC surface.