Current Organic Chemistry - Volume 29, Issue 14, 2025

Phenanthrenes and their dihydro derivatives have attracted considerable attention due to their widespread occurrence in natural products and pharmaceuticals with biological activities, which have led to their application in the treatment of microbial or viral infections, allergies, cancer, and malaria. Nowadays, the transitional metal-catalysed reactions are useful approaches for the synthetic transformation of organic compounds due to high yield and step economy. This approach, owing to the use of non-pre functionalized substrates, minimizes the chemical wastes. Among the various synthetic strategies, metal-catalyzed C-H bond activation and also Heck reactions have recently drawn a lot of interest in synthesizing decorated π-conjugated polycyclic aromatic hydrocarbon. In this review, we have focused on recent progress along with previous strategies to synthesize various phenanthrene and its derivatives by the use of metal-catalyzed reactions and also discussed the mechanistic details of the reaction.

Chitosan is a natural biopolymer derived from chitin present in the exoskeletons of crustaceans. Its diverse applications span biomedical products, agriculture, and cosmetics. Notably, chitosan has been effectively utilized for chemical modifications and stabilizing homogeneous catalysts. Among these modifications, doping with acids or inorganic salts stands out. In some cases, acid chitosan exhibits superior catalytic activity compared to the unmodified form. This review aimed to elucidate recent advancements in acidic chitosan as a renewable and recoverable catalyst for various reactions. The discussion encompasses different doping methods using organic acids and inorganic salts to highlight the development in this field.

In India, Ichnocarpous frutescens Linn R. Br. (I. frutescens) is a woody climbing shrub belonging to the Apocynaceae family. Tribes traditionally use it as a substitute for Indian Sarsaparilla (Hemidesmus indicus) to treat conditions such as delirium, convulsions, atrophy, diarrhea, measles, splenomegaly, tuberculosis, tumours, and diabetes. It has also been used as a lactagogue, antipyretic, demulcent, diaphoretic, and skin moisturizer. This study aimed to gather information on the phytochemistry, traditional applications, and pharmacological properties of I. frutescens. Various scientific studies have evaluated their phytochemical components and therapeutic potential. Phytochemical studies have identified 28 compounds, including triterpenes, flavonoids, phytosterols, and other phenolic compounds. Several pharmacological effects of plant extracts have been documented, including anticancer, antiurolithiatic, hepatoprotective, antioxidant, analgesic, antipyretic, anti-inflammatory, antidiabetic, and antihyperlipidemic activities. Additionally, this review examines the biological mechanisms underlying these pharmacological actions, emphasizing the potential therapeutic applications of the plant. By consolidating the current knowledge, this review serves as a valuable resource for further research and potential utilization of I. frutescens in modern pharmacotherapy, paving the way for future studies to explore its full range of effects and uses.

Efficient synthesis of heterocyclic has always been a very important task in drug discovery. Most of the drugs contain heterocycles to provide an interface between chemistry and biology. Among the various heterocyclic compounds, quinazoline, a heterocyclic compound, offers multiple advantages like pyrimidine, pyridine, piperidine, imidazole, morpholine, quinoline, purine, etc. Many research groups have demonstrated numerous synthesis techniques to harvest the advantage of quinazoline. Therefore, it is necessary to understand the various aspects of the development techniques of quinazoline as industry-oriented application. Various methodologies have been recently developed for the formation of quinazoline moiety. In this review article, the synthetic methods of quinazoline derivatives are classified based on metal-catalysed and miscellaneous synthetic aspects.

The synthesis of bis-indole methanes (BIMs) is a significant area of research in organic chemistry due to their diverse biological activities and applications in pharmaceuticals. This review focuses on the acid-catalyzed synthesis of BIMs, offering a comprehensive overview of various catalytic systems, reaction mechanisms, and optimization strategies. Acid catalysts, including Bronsted, Lewis acids, solid acids, and homogeneous acids, play a crucial role in facilitating the formation of BIMs through electrophilic substitution reactions. The review insights into different acid catalysts, such as Meldrum's acid, boric acid, and various solid acids, and highlights their efficiency, selectivity, and environmental impact. Additionally, the influence of reaction conditions, such as temperature, solvent selection, and substrate concentration, on the yield and purity of BIMs are discussed. Moreover, recent advances in green chemistry approaches, including using recyclable and solid acid catalysts, are explored. This comprehensive study aims to provide insights into the optimization of acid-catalyzed BIM synthesis, paving the way for future developments in synthesizing biologically relevant indole derivatives.