Chromanes are privileged scaffolds in medicinal chemistry because they exhibit diverse biological activities. Their stereoselective synthesis has become a critical objective in drug development. The emergence of organocatalysis has sparked a paradigm shift in synthetic chemistry by offering a highly selective alternative to traditional metal-catalyzed reactions. This review discusses the transformative impact of organocatalyzed reactions on the asymmetric synthesis of chromane derivatives, focusing on key classes of catalysts such as chiral phosphoric acid, chiral amines, bifunctional systems, and others reported since 2020. Organocatalysis not only achieves high levels of stereocontrol but also adheres to the principles of green chemistry by eliminating toxic metals and enabling mild reaction conditions. These advancements diversify synthetic methodologies and establish organocatalysis as a fundamental approach in the sustainable synthesis of bioactive chromanes.

A green and efficient deep eutectic solvent (DES)-mediated multicomponent strategy has been developed for the synthesis of spiro[naphthalene-2,5'-pyrimidine]-4-carbonitriles. This protocol utilizes a biodegradable choline chloride/urea (1 : 2) DES as a sustainable reaction medium, and offers a good yield of targeted products (67-93%), broad substrate scope and high atom economy, while eliminating volatile organic solvents and harsh conditions. The DES can be easily recovered and reused for multiple cycles with minimal loss of efficiency. With operational simplicity, straightforward isolation and excellent recyclability, this approach offers practical and environmental benign multicomponent synthesis of spiro[naphthalene-2,5'-pyrimidine]-4-carbonitriles. The synthesized compounds were also docked and molecular dynamics (MD) simulations was performed to investigate the binding affinity, molecular interactions and stability of our synthesized spiro[naphthalene-2,5'-pyrimidine]-4-carbonitriles with the amino acids of coronavirus main protease (6LU7). All the compounds were found to be potent in comparison with reference inhibitor, remdesivir (-6.62 kcal mol-1) with binding energies ranging from -7.53 to -9.98 kcal mol-1. Overall, the present study demonstrates an efficient and sustainable DES-mediated strategy for the synthesis of biologically important spiro[naphthalene-2,5'-pyrimidine]-4-carbonitrile derivatives with promising antiviral potential against SARS-CoV-2 Mpro. The integration of green synthetic methodology with favourable in silico biological evaluation highlights the medicinal significance of this approach and its potential to promote future antiviral drug discovery research.

In a variety of reactions, oxalic acid has shown itself to be a flexible natural organic catalyst that effectively promotes the synthesis of complex organic compounds. Its importance in contemporary organic synthesis is highlighted by its diversity of uses, which include metal-free methods for creating valuable compounds and deep eutectic solvents (DES) for high-yield syntheses. This review delves into the multifaceted catalytic roles of oxalic acid, elucidating its function as a powerful Brønsted acid for various transformations and its synergistic behaviour within DES systems. This review meticulously showcases its utility in the synthesis of a wide array of biologically significant heterocyclic scaffolds. Future studies might focus on improving these reactions even further and investigating novel applications for oxalic acid in organic transformations including multicomponent systems, solidifying its pivotal role in advancing green chemistry.

The development of small-molecule tyrosine kinase inhibitors remains a high-priority strategy in modern oncology, particularly those targeting the Vascular Endothelial Growth Factor Receptor 2 (VEGFR-2) to disrupt pathological angiogenesis. This study utilized a dual-methodology approach to evaluate a novel series of five coumarin nucleoside conjugates (5a-5e) as potential anti-cancer agents. Initially, the compounds’ drug-likeness was confirmed via ADMET prediction, which established favorable pharmacokinetic profiles. This was followed by an integrated MTT cytotoxicity screening against Oct1 (head and neck) and C33a (cervical) cancer cell lines, which identified compound 5d as the most potent cellular agent. The core of the investigation involved a comprehensive in silico analysis targeting the VEGFR-2 tyrosine kinase domain (TKD). Molecular docking revealed that all five compounds possess significantly superior predicted binding affinities compared to the native ligand, ATP (− 25.44 kJ/mol). Critically, the primary cellular lead 5d (− 29.46 kJ/mol) and the strongest binder 5e (− 31.30 kJ/mol) both surpassed the affinity of the clinical benchmark, Sorafenib (− 28.80 kJ/mol), confirming their high potential as competitive inhibitors. Further validation using Molecular Dynamics (MD) simulation and MMPBSA analysis demonstrated exceptional dynamic stability and thermodynamic preference for the TKD-ligand complexes, firmly supporting the predicted binding hypothesis. In conclusion, compounds 5d and 5e are validated lead candidates possessing favorable absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties, direct cellular cytotoxicity, and a robust computationally modeled dual-action profile. Future research is urgently mandated to perform VEGFR-2-specific functional assays to definitively validate the predicted anti-angiogenic mechanism and conduct in-vivo studies to assess therapeutic efficacy.

Corrosion is a significant issue affecting industrial metal surfaces, resulting in material degradation, economic losses, and safety concerns. This review comprehensively examines chitosan and its nano and bionanocomposite forms as sustainable, eco-friendly corrosion inhibitors, emphasizing key innovations in their development and application. The article highlights chitosan's ability to form protective films, which inhibit corrosion by creating a barrier on metal surfaces. A key advancement explored is the incorporation of chitosan nanoparticles, which significantly improve corrosion resistance due to their enhanced surface area, increased adhesion properties, and improved mechanical strength. Another innovative aspect is the synergistic effect of combining chitosan with other nanoparticles or inhibitors, resulting in superior corrosion protection and enhanced barrier properties. The review also addresses the chemical modifications of chitosan to overcome challenges such as poor solubility, mechanical weakness, and chemical instability in harsh environments. A novel contribution of this article is the focus on scalable, cost-effective production methods for chitosan-based bionanocomposites, facilitating their industrial application. This review provides a comprehensive summary of literature reports, offering valuable insights into the latest research advancements and highlights future prospects for chitosan-based materials as eco-friendly, high-performance corrosion inhibitors in diverse industrial settings.

Paclitaxel is one of the most widely utilized anticancer drug. It displays a range of antitumor action, particularly against ovarian cancer, urologic malignancies, head tumor, and Kaposi’s sarcoma. However, due to its highly lipophilic nature, poor fluid dissolvability of less 0.01 mg/mL and lack of ionizing functionalities which may enhance its solubility, there are substantial challenges associated with Paclitaxel delivery. Paclitaxel exhibited promising effects when formulated in combination with ethanol and Cremophor EL, as Taxol®. However, it is associated with various side effects, including hypersensitivity, hypotension, and peripheral neuropathy. The albumin-based Paclitaxel, Abraxane®, is a superior alternative to Taxol® as it diminishes the side effects related to Cremophor EL. Abraxane® is regarded as the gold standard for cancer treatment, but its 21

Carbohydrates and their analogues play a unique role in all living organisms and therefore have played a supremacy role in molecular recognition, energy supply, drug discovery, etc. During the last few decades, biocatalyst lipases have emerged as one of the greener and sustainable catalysts in comparison to traditional synthetic catalysts for the synthesis of modified carbohydrates and their analogues. Because lipase is a natural catalyst, it shows outstanding selectivity, reactivity, amazing tolerance, and assistance in carrying out eco-friendly greener methodology. The application of biocatalyst lipase as a chemo- and regio-selective catalyst is particularly relevant for organic chemists for the synthesis of modified carbohydrates, because carbohydrates contain several identical hydroxyl groups. Herein, we discussed the recent developments in the lipase Novozyme-435 mediated synthesis of modified carbohydrates and their biological significance.

Among the diverse natural catalysts, caffeine has emerged as a green, expedient, non-toxic, and biodegradable catalyst. The main objective of this review is to present the existing knowledge pertaining to the exploitation of caffeine in various organic transformations.

Chromones are well known as fundamental structural elements found in numerous natural compounds and medicinal substances. The Schiff bases of chromones have a much wider range of pharmacological applications such as antitumor, antioxidant, anti-HIV, antifungal, anti-inflammatory, and antimicrobial properties. A lot of research has been carried out on chromone-based copper(ii) Schiff-base complexes owing to their role in the organometallic domain and promise as potential bioactive cores. This review article is centered on copper(ii) Schiff-base complexes derived from chromones, highlighting their diverse range of pharmacological applications documented in the past decade, as well as the future research opportunities they offer.

Pyrimidine is a pharmacologically important moiety that exhibits diverse biological activities. This review reflects the growing significance of transition metal-catalyzed reactions for the synthesis of pyrimidines (with no discussion being made on the transition metal-catalyzed functionalization of pyrimidines). The effect of different catalysts on the selectivity/yields of pyrimidines and catalyst recyclability (wherever applicable) are described, together with attempts to illustrate the role of the catalyst through mechanisms. Although several methods have been researched for synthesizing this privileged scaffold, there has been a considerable push to expand transition metal-catalyzed, sustainable, efficient and selective synthetic strategies leading to pyrimidines. The aim of the authors with this update (2017-2023) is to drive the designing of new transition metal-mediated protocols for pyrimidine synthesis.

In recent years, Sulfonyl hydrazides have emerged as powerful reagents for sulfonyl sources because of their easy availability, stability, and non-toxic nature. The hydrazinyl group can be easily detached from sulfonyl hydrazides using oxidative, thermal, radical, basic, or metal-catalyzed conditions. In this review, we have collected recent protocols for preparing sulfones, sulfides, and sulfoxides from the ideal starting material, sulfonyl hydrazides using various transition metals or in metal-free conditions.

The advent of nanotechnology has helped in several invention in science & technology. Contamination of surface water, ground and soil by various industrial dyes causes several ecological problems. Zinc oxide nanoparticles as photocatalysts and semiconductor materials show unique physical properties at the nanoscale and can be used to solve these problems to some extent. In this paper, we synthesized ZnO NPs and calcium-coated ZnO nanoparticles using extract of beetroot and then, for industrial point of view, we studied the photocatalytic degradation of methylene blue and rhodamine B using sun as a natural light source (sunlight). We have synthesized calcium-coated ZnO nanocomposites with 20–50 nm particle size. Synthesized nanomaterials were characterized by using the different physio-chemical techniques such as - FT-IR, XRD, TEM, SEM, EDX and UV-spectrophotometer do their photocatalytic degradation.

A proficient approach has been developed for the synthesis of substituted 2H-chromenes from C1-substituted glucal. The key step of our synthetic methodology was C–H activation in propylene carbonate solvent followed by 6π-electrocyclization aromatization in ethylene glycol as greener substitutes to toxic aprotic solvents, to obtain 2H-chromenes in a stepwise manner. The application of the developed methodology was further explored with the synthesis of a small library of substituted 2H-chromenes in good yields.

Fossil fuels are the main energy sources worldwide even today. But with the alarming pace at which fossil fuels are exhausting, there would be a need for sustainable and economically viable alternatives in the near future. Fossil fuels pose severe environmental threats like air pollution, soil pollution, global warming etc. It is reported that the utilization of algal biomass to produce bioenergy could be one of the solutions. Microalgae offer many unique features with the potential to store lipids in their cells just like plant oils, CO2 sequestering capability, low space requirement, rapid growth, ability to grow in wastewater and rich in lipid and carbohydrate content. Although an array of nutrients is required for an algal bloom that could be fulfilled by nutrients from wastewater. In a way, it is the biological wastewater treatment technology producing green energy (WtE). Methods like supercritical fluid extraction, microwave and ultrasonic-assisted extraction, and Soxhlet extraction could be used for the microalgal lipid extraction. So, this chapter explores the possible methods to isolate lipids from biomass and their energy utilization.

With the rapid developments in science and technology, the demand for critical materials, comprising gold, platinum-group metals, and rare earth elements, is rising rapidly. The harmful impact on the life cycle of living beings has prompted an increase in interest in studies focusing on the removal of metals from industrial effluents. Metals are divided into four categories depending on their properties. The first category includes harmful heavy metals like Ti, Ag, Si, Sr, As, Pb, Cr, and Hg. The second category includes radioactive metals like Am, Ra, Th, Rn, U, and Tc. The third category includes metals necessary for metabolisms, such as Zn, Cu, Ni, Fe, Ca, K, and Mo. The last category includes metals used to identify the efficiency of biological systems, such as B, Po, Te, Sb, and Ge. The primary sources of these metals are several industries, including those that produce coating, paper, metallurgy, tanning, mining, batteries, agricultural chemicals, and other industries. Currently, the emphasis of the study is on the removal of metals and their subsequent reuse for numerous productive purposes. Here in this chapter, we will be discussing the recovery of resources from wastewater using commonly practised Physico-chemical pathways.

Multicomponent reactions (MCRs) cover strategically employed chemical transformations that incorporate three or more reactants in one pot leading to a functionalized final product. Thus, it is an ideal tool to achieve high levels of complexity, diversity, yields of desired products, atom economy, and reduced reaction times. Sugars belong to the class of naturally occurring compounds with fascinating applications in the field of drug discovery due to the presence of various hydroxy groups and well-defined stereochemistry. However, their potential in MCRs has been realized only recently. This account describes recent advances in the synthesis of sugar-derived heterocycles synthesized by MCRs. We hope to encourage the synthetic and medicinal chemistry community to apply this powerful MCR chemistry to generate novel glycoconjugate challenges.1 Introduction2 Synthesis of Various Functionalized Sugar Compounds2.1 Passerini and Ugi Multicomponent Reactions2.2 Petasis Reaction2.3 Hantzsch Reaction2.4 Domino Ferrier–Povarov Reaction2.5 Marckwald Reaction2.6 Groebke–Blackburn–Bienaymé (GBB) Reaction2.7 Prins–Ritter Reaction2.8 Debus–Radziszewski Imidazole Synthesis Reaction2.9 Mannich Reaction2.10 A3-Coupling Reaction2.11 [3+2]-Cycloaddition Reactions2.12 Miscellaneous Reactions3 Conclusion