Mini-Reviews in Organic Chemistry - Volume 22, Issue 4, 2025

The mesoionic compounds have great importance due to their dipolar nature. They are versatile synthons in synthetic chemistry and possess various chemotherapeutic activity. The most important moiety found in mesoionic compounds is the sydnone ring system. Sydnone derivatives have stimulated much interest among synthetic researchers as a result of their unique dipolar, mesoionic character. This ring system is also associated with a wide variety of biological activities. Sydnones derivatives have various applications synthetic and medicinal chemistry. Sydnones serve as very useful precursors for selective heterocycles (pyrazoles, imidazoles, oxadiazoles, oxazoles, thiazoles, tetrazoles) which has also served to initiate research into their functionalization and cycloaddition chemistry. Which proved stimulated extensive research of sydnones under chemical and its probable industrial applications. So, this mini-review article offers a wide scope of synthesis and applications of sydnones derivatives.

Microbial derivatives are a significant source of antioxidants, with varying structures leading to different activities due to distinct structure-activity relationships. These structures include polyketones, alkaloids, terpenes, and fatty acids. Microbial-derived antioxidants offer unique advantages, such as diversity, high yield, customizability, sustainability, and biocompatibility, making them promising for various applications. This review aims to address the following objectives: (1) to explore the antioxidant activities of microbial derivatives with these specific structures, (2) to detail their biosynthesis processes, and (3) to lay the groundwork for their further utilization and development in diverse fields.

The demand for crop yields is increasing in modern society. The challenges to agricultural cultivation, nevertheless, are posed by soil degradation, pollution, and the increasing number of extreme weather events due to climate change. All these factors can threaten crop yield and quality. However, fulvic acid can effectively alleviate these problems. It’s a type of humus with multiple agricultural values, is produced through biomass fermentation, and has various mechanisms that promote crop growth. It plays a significant role in mitigating various adverse factors affecting crop growth. Fulvic acid contains more carboxyl and hydroxyl groups but also the presence of ether bonds and ester bonds, due to the special structure of xanthic acid, which also allows it to closely bond with many metal ions and substances. This paper provides an in-depth study of the mechanism and molecular structure of fulvic acid production and describes a variety of application scenes of fulvic acid in agricultural production. This paper makes a general conclusion on the improvement of yield and quality of yellow rot crops and analyzes the resistance of yellow rot to the adverse environment, including heavy metal hazards, salt stress hazards, drought hazards, pests, and diseases. Through the analysis by many scholars, yellow rot acid can play a significant role in the improvement of the adverse environment growing plants.

Furthermore, the combined use of fulvic acid and modern drip irrigation techniques is receiving increased attention due to the significant benefits it offers in terms of water management and enhanced fertilizer efficiency. More studies should be conducted on the mechanism of xanthate in plants. The characterization of fulvic acid properties is indispensable in practical agricultural applications. Moreover, the development of effective fulvic acid derivatives according to the actual situation is essential to promote the sustainable development of agriculture.

The simple separation of magnetic nanocatalysts from the reaction mixture using only an external magnet caused a huge revolution in catalysis, particularly in organic synthesis. Diaryl ethers compounds containing (Ar-O-Ar linkages) are one of the most important and prominent compounds and are widely found in natural products and pharmaceutical and biological molecules. The C-O cross-coupling or O-arylation reactions of aryl halides with aromatic alcohols, especially phenols, is an important and straightforward strategy for the preparation of diaryl ethers. Due to the high importance of diaryl ethers in the pharmaceutical, chemical and medical fields, many efforts have been made for the synthesis of diaryl ethers through C-O cross-coupling aryl halides with aromatic alcohols, especially phenols based on using non-magnetic reusable catalysts. In this review, we carefully reviewed the synthesis of diaryl ethers and discussed the reaction conditions and product yields in each method.

The imidazole ring is a five membered ring with a simple chemical structure and is widely present in natural products. Due to its unique chemical structure, it is beneficial for the imidazole ring to bind with other functional groups, thus exhibiting a wide range of biological activities. The synthesis of imidazole derivatives often involves the Debus method, Michael addition method, and the use of existing materials to synthesize target compounds through one-pot synthesis. Imidazole compounds have numerous medicinal properties and physiological activities, including antioxidant, antibacterial, anti-inflammatory, antihistamine, hypoglycemic, antiviral, antihypertensive and anticancer effects. In addition to its medicinal chemical significance, imidazole also has industrial applications such as corrosion inhibitors, flame retardants, photography, and electronics. The synthesis and activity research of imidazole and its derivatives have good development prospects. This article reviews the chemical synthesis and biosynthesis of imidazole derivatives, as well as their biological activities.