Dhakshanamurthy Thirumalai

Green‐synthesized rGO‐CeO ₂ nanocomposites (NCs) were fabricated using an eco‐friendly approach, in which the leaf extract of Saraca asoca ( Sa ) served as a natural reducing and stabilizing agent. Reduced graphene oxide (rGO) was obtained through the chemical reduction of graphene oxide (GO) and combined with CeO ₂ nanoparticles (NPs) via a simple physical grinding method to produce uniform nanocomposites. Comprehensive characterization using X‐ray diffraction (XRD), Fourier‐transform infrared (FT‐IR), UV‐vis diffuse reflectance spectroscopy (UV‐DRS), field emission scanning electron microscopy (FE‐SEM), High‐Resolution Transmission Electron Microscopy (HR‐TEM), energy‐dispersive x‐ray (EDX), thermogravimetric analysis (TGA), x‐ray photoelectron spectroscopy (XPS), zeta potential, and Brunauer–Emmett–Teller (BET) analyses confirmed the formation of face‐centered cubic CeO ₂ , with spherical and hexagonal nanoparticles uniformly anchored onto rGO sheets and an average particle size of 16.82 nm. Optical analysis revealed a reduced band gap of 2.73 eV, while XPS results confirmed the coexistence of mixed cerium oxidation states (Ce ³⁺ /Ce ⁴⁺ ). Under visible light irradiation (500 W), the rGO‐CeO ₂ NCs demonstrated excellent photocatalytic performance, achieving 93.78% degradation of Eosin Y (EY), a reddish‐pink fluorescent dye, following a first‐order kinetic model. Radical scavenging experiments indicated that hydroxyl (•OH) and superoxide (•O ₂ ⁻ ) radicals were the primary reactive species involved in the degradation process. Moreover, the NCs exhibited good structural stability and retained high photocatalytic efficiency over multiple reuse cycles, highlighting their potential as cost‐effective photocatalysts for the treatment of dye‐contaminated textile wastewater.

A versatile method has been developed for the synthesis of morpholine‐dihydropyrimidine hybrids, 3‐benzyl‐6‐methyl‐5‐(morpholine‐4‐carbonyl)‐4‐phenyl‐3,4‐dihydropyrimidin‐2(1H)‐one, through the construction of dihydropyrimidine (DHPM) via the guanidine‐based Biginelli reaction followed by sodium tertiary butoxide mediated substitution of the benzyl group at the 3 ^rd position of DHPM ring. This substitution approach represents a novel method for obtaining N ‐substituted Biginelli products in good yields (72%–84%). Further, the ester group was subjected to intergroup conversion by morpholine using in situ generated diisobutyl(morpholino)aluminum. Notably, this reaction exhibited tolerance to various functional groups, resulting in the corresponding derivatives of dihydropyrimidine–morpholine hybrids in excellent yield (62%–82%).

Ammonium trifluoroacetate (ATA) catalysed synthesis of 1,2,5,6‐tetrahydropyridine (THP) derivatives, under eco‐friendly conditions via a facile one‐pot strategy. We have synthesized fifteen THP derivatives, and docked into the crystal structure of Phosphatase and Tensin Homolog deleted on Chromosome 10 (PTEN) tumour suppressor protein (PDB ID: 1D5R) based on drug‐likeness prediction and pharmacokinetic properties. Molecular docking simulation studies reveal that four of our synthesised compounds are potential hit candidates because they bound to the receptor through 5–7 conventional hydrogen bonds with −9.7 to −8.6 kcal/mol of binding energy. The compounds were evaluated using the in vitro inhibitory activity of MCF‐7 breast cancer cell lines. Identified hit compounds showed moderate inhibition at (160–320 μg/mL) and inhibitory concentration IC ₅₀ values in the low micromolar range of 171.062, 189.803, 195.469 and 181.272 μg/mL respectively. The results obtained are very promising; therefore fine‐tuning the substituents of hit molecules with appropriate bioisosteres can lead to the development of potential leads.

Malaria is one of the most known vector-borne diseases caused by female Anopheles mosquito bites. According to WHO, about 247 million cases of malaria and 619,000 deaths were estimated worldwide in 2021, of which 95% of the cases and 96% of deaths occurred in the African region. Sadly, about 80% of all malaria deaths were of children under five years old. Despite the availability of different insecticides used to control this disease, the emergence of drug-resistant mosquitoes threatens public health. This, in turn, highlighted the need for new larvicidal agents that are effective at different larval life stages. This study aimed to identify novel larvicidal agents. To this end, a series of ethyl 2,4,6-trisubstituted-1,4-dihydropyrimidine-5-carboxylates 8a-i was synthesized using a three-step chemical synthetic approach via a Biginelli reaction employed as a key step. All title compounds were screened against Anopheles arabiensis to determine their larvicidal activities. Among them, two derivatives, ethyl 2-((4-bromophenyl)amino)-4-(4-fluorophenyl)-6-methyl-1,4-dihydropyrimidine-5-carboxylate 8b and ethyl 2-((4-bromo-2-cyanophenyl)amino)-4-(4-fluorophenyl)-6-methyl-1,4-dihydropyrimidine-5-carboxylate 8f, showed the highest larvicidal activity, with mortality of 94% and 91%, respectively, and emerged as potential larvicidal agents. In addition, computational studies, including molecular docking and molecular dynamics simulations, were carried out to investigate their mechanism of action. The computational results showed that acetylcholinesterase appears to be a plausible molecular target for their larvicidal property.Communicated by Ramaswamy H. Sarma.