Mini-Reviews in Organic Chemistry - Volume 17, Issue 5, 2020

In recent years, the interest in biologically active compounds of natural origin has increased significantly. Researchers' research focuses on increasing the activity of curcumin by forming complexes with metals such as vanadium, iron, copper or gallium. Introduction of metal compounds to curcumin increases the scope of application in pharmacology. The main direction of research development is the treatment of tumors, among others stomach cancer or leukemia. Curcuminoids are the main components of turmeric (Curcuma longa L.), a plant from India and South-East Asia. Due to its intense yellow-orange color and pleasant aroma, the powdered rootstalk is widely used in the food industry, as natural dye and spice. The chemical compound responsible for the characteristic color of rhizomes of curcuma is 1,6-heptadien-3,5-dione-1,7-bis(4-hydroxy-3-methoxyphenyl) - (1E, 6E) called curcumin. This work aims to characterize curcumin in terms of its structure, therapeutic properties and also as a substrate for the synthesis of valuable derivatives like tetrahydrocurcumin. Knowledge about this relationship based on literature analysis will enable a better understanding of the factors responsible for its biological activity.

Patrinia scabiosaefolia Fisch. Trev. and Patrinia villosa (Thunb.) Juss, are two species of Patrinia recorded in the Chinese Pharmacopoeia with the same Chinese name “Baijiangcao” and similar therapeutic effect in traditional Chinese medicine. The present article is the first comprehensive review on the chemical composition and pharmacological activities of these herbs. In this review, data on chemical constituents and pharmacological profile of the two herbs are provided. This review discusses all the classes of the 223 compounds (phenylpropanoids, flavonoids, terpenes, saponins and volatile components, etc.) detected in the two herbs providing information on the current state of knowledge of the phytochemicals present in them. In the past three years, our research group has isolated and identified about more than 100 ingredients from the two herbs. Therefore, we published a systematic review of our research papers and studies on the two herbs were carried out using resources such as classic books about Chinese herbal medicine and scientific databases including Pubmed, Web of Science, SciFinder, CNKI. etc. The present review discusses the most thoroughly studied pharmacological activities (antioxidant, anti-inflammatory, immunomodulatory, antimicrobial, antitumor and antiviral activities) of the two herbs. This comprehensive review will be informative for scientists searching for new properties of these herbs and will be important and significant for the discovery of bioactive compounds from the two herbs and in complete utilization of Patrinia scabiosaefolia Fisch. ex Trev. and Patrinia villosa (Thunb.) Juss.

Primarily composed of organic molecules, pharmaceutical materials, including drugs and excipients, frequently exhibit physicochemical properties that can affect the formulation, manufacturing and packing processes as well as product performance and safety. In recent years, researchers have intensively developed Crystal Engineering (CE) in an effort to reinvent bioactive molecules with well-known, approved pharmacological effects. In general, CE aims to improve the physicochemical properties without affecting their intrinsic characteristics or compromising their stability. CE involves the molecular recognition of non-covalent interactions, in which organic materials are responsible for the regular arrangement of molecules into crystal lattices. Modern CE, encompasses all manipulations that result in the alteration of crystal packing as well as methods that disrupt crystal lattices or reduce the size of crystals, or a combination of them. Nowadays, cocrystallisation has been the most explored strategy to improve solubility, dissolution rate and bioavailability of Active Pharmaceutical Ingredients (API). However, its combinatorial nature involving two or more small organic molecules, and the use of diverse crystallisation processes increase the possible outcomes. As a result, numerous organic materials can be obtained as well as several physicochemical and mechanical properties can be improved. Therefore, this review will focus on novel organic solids obtained when CE is applied including crystalline and amorphous, single and multicomponent as well as nanosized ones, that have contributed to improving not only solubility, dissolution rate, bioavailability permeability but also, chemical and physical stability and mechanical properties.

α-Substituted α,β-unsaturated aldehydes represent a highly reactive class of compounds with a broad scope of application. Therefore, the development of methods for the synthesis of these bifunctional compounds is a dynamically progressing area of research. This review summarizes and highlights methods for the synthesis of α-alkyl α,β-alkenals.

Resveratrol is a polyphenolic compound and has been shown to possess numerous biological activities, which could possibly be applied to the prevention and/or treatment of cancer, cardiovascular disease, and neurodegenerative diseases. This review summarizes the progress of different chemical methods in the preparation of resveratrol.

Combining palladium catalyzed reactions in one-pot reactions represents an efficient and economical use of catalyst. The Suzuki-Miyaura cross-coupling has been proven to be a reaction which can be combined with other palladium catalyzed reactions in the same pot. This mini-review will highlight some of the latest examples where Suzuki-Miyaura cross-coupling reactions have been combined with other palladium catalyzed reactions in one-pot reaction. Predominantly, examples with homogeneous reaction conditions will be discussed in addition to a few examples from the authors where Pd/C have been used as a catalyst.

Acrylonitrile is a key precursor in the production of a wide range of products in the chemical industries. The major products of acrylonitrile include acrylonitrile butadiene styrene resin, acrylic fibers, and adiponitrile. The demand for the roduction of acrylonitrile is affected by the global economy but because of the development of living standards; the demand for producing acrylonitrile and its derivations are significantly increasing. So in 2016, China alone produced 32% of the world’s acrylonitrile, and its production is expected to have a 55% increase in 2021. Acrylonitrile and its derivations have wide applications in different industries like car manufacturing, electronics, aerospace, and textile. Considering the importance of the acrylonitrile precursor in the current world, in this study, we discuss and investigate its production processes, the obtained copolymers, and polyacrylonitrile production and its application in the carbon fibers and compare it with other carbon fiber precursors such as mesophase pitch and cellulose. We also focus on its marketing in the world.

Solid supported catalysts have been of considerable interest in organic synthesis for the last few years. Solid support provides an efficient heterogeneous catalytic system owing to facile recovery and extensive recycling by simple filtration because of possessing 3-R approach (Recoverable, Robust and Recyclable) and makes solid supported catalyst more appealing nowadays. In view of the high cost and shortage of furthermost used palladium catalyst, its recovery and recycling are vital issues for any large-scale application which are being overcome by using solid supported catalytic systems. Therefore, a variety of inorganic and organic solid-supported catalytic systems have been developed so far in order to address these challenges. This review attempts highlight a number of solid supported catalytic systems in the pro-active area of widely used C-C cross coupling reactions.

3-Amino-1,2,4-triazines are considered versatile compounds for its significance as building blocks in synthetic and pharmaceutical chemistry. The synthesis, chemical reactivity, and applications of substituted 1,2,4-triazines bearing an amino group were described in this review. The presence of the amino group at position 3 exhibited unique reactivities towards carbonitrile, carbonyl and isothiocyanate reagents. The reactions were divided into several categories, depending on the other substituents on the 1,2,4-triazine ring. In this review, relevant and appropriate applications of the synthesized, isolated, and condensed heterocycles derivatives were reported.