More than half of drugs are chiral compounds with their chirality determining their molecular interactions, ecofriendly environmental safety and efficacy. Overall nearly 90% of chiral compounds are marketed as racemates consisting of an equimolar mixture of two enantiomers. Despite having identical chemical structure and bonding, racemates function differently when exposed to chiral environments and demonstrate notable variances in biological properties such as pharmacology, toxicology, metabolism and pharmacokinetics, etc. Advancements in asymmetric synthesis in recent years have led to considerable interest in the development of single enantiomers of chiral drug molecules for medicinal chemistry settings. In this review, we want to compile examples of chiral medicines approved by the FDA in the years 2022 and 2023 with an emphasis on their synthesis along with information on chiral induction as well as enantiomeric excess.

We have described the simple, convenient and high yielding one-pot synthesis of a library of highly functionalized hexa-substituted 1,4-dihydropyridines (1,4-DHPs) by 2-aminopyridine catalysed pseudo three-component reaction of nitroketene-N,S-acetals and aldehydes. This domino transformation involves formation of dihydropyridine ring by creation of two C–C bonds and one C–N bond, all of them taking place in a single synthetic operation. As the products precipitate out of the reaction simple filtration is enough to gather the products and thus, there is no need for work-up or column-chromatography. The C6-methylsulfanyl group in the product 1,4-DHPs was substituted with primary and secondary amines to provide 1,4-DHPs with further possibilities in structural diversity. As a demonstration of application of the method we have synthesised an analogue of nitenpyram, a neonicotinoid insecticide.

Mangrove ecosystem has many potential species that are traditionally used by the coastal communities for their traditional cure for health ailments as evidenced by their extensive uses to treat hepatic disorders, diabetes, gastrointestinal disorders, anti-inflammation, anticancer, and skin diseases, etc. In recent times, the diabetes mellitus (DM), a serious physiological disorder all over the world, occur due to the relative or complete deficiency of insulin in the body, characterized by an abnormally high blood glucose level. India has a rich traditional knowledge on plant-based drug formulations that are protective and curative for many health ailments. In this context, we aimed to compile the works done on the antidiabetic activities of mangrove species from Indian coastal regions especially on Andaman and Nicobar Islands as well as some recent works reported from other countries. A total of 126 published articles and 31 mangrove species related pieces of information were gathered with reference to antidiabetic properties of mangroves. This review summarizes the chemical structures, molecular formula, molecular weight, and their biological activities with an aspiration that it might be helpful for the future bioprospecting industries who are interested in develop the natural drugs for DM.

Gallic acid (PubChem CID: 370) and quercetin (PubChem CID: 5280343) are major phenolic compounds in many mangrove plants that have been related to health cure. In the present study, the active fractions namely gallic acid (1) and quercetin (2) were isolated from the methanolic extract of leaves of Ceriops tagal in a Tropical mangrove ecosystem of Andaman and Nicobar Island (ANI), India. The chemical structures were determined by spectroscopic analysis: Fourier-Transform Infrared spectroscopy (FT-IR), ¹H, ¹³C Nuclear Magnetic Resonance (NMR) spectroscopy, and High-resolution mass spectrometry (HRMS). The anticancer activity of isolated compounds (1) and (2) were evaluated by in vitro assays against two human cancer cell lines namely, HeLa (Cervical) and MDA-MB231 (Breast) cancer cells revealed that IC₅₀ values of gallic acid (HeLa: 4.179197 ± 0.45 µg/ml; MDA-MB231: 80.0427 ± 0.19 µg/ml at 24 h) and quercetin (HeLa: 99.914 ± 0.18 µg/ml; MDA-MB231: 18.288382 ± 0.12 µg/ml at 24 h), respectively. Antioxidant properties of gallic acid (1) and quercetin (2) are found to be IC₅₀ value of 0.77 ± 0.41 µg/ml and 1.897 ± 0.81 µg/ml, respectively. Molecular docking results explained that gallic acid (1) and quercetin (2) showed estimated binding free energy (ΔG) of −5.4 and −6.9 kcal/mol towards drug target Bcl-B protein, respectively. The estimated inhibition constant (Ki) for these two molecules are 110 and 8.75 μM, respectively. The MD simulation additionally supported that quercetin molecule is significantly improved the structural stability of Bcl-B protein. The present study provides key insights about the importance of polyphenols, and thus leads to open the therapeutic route for anti-cancer drug discovery process. Communicated by Ramaswamy H. Sarma

Herein, we present the iodine catalyzed an efficient synthesis of imidazo[1,2-a]pyrazine and pyridine derivatives and studied their anticancer activities against in vitro cancer cell lines namely, Hep-2, HepG2, MCF-7, and A375.