Synthetic Modifications of Andrographolide Targeting New Potential Anticancer Drug Candidates: A Comprehensive Overview

This review collects the synthetic modifications performed on andrographolide, a natural molecule derived from Andrographis paniculata, for oncology applications. Various pharmacomodulations were carried out, and the products were tested on different cancer cell lines. The impact of these modifications was analyzed with the aim of mapping the positions essential for activity to facilitate future research in this field. However, this study makes it clear that, in addition to structural modifications of the molecule, which can result in varying degrees of effectiveness in targeting interactions, the lipophilic capacity of the structures obtained through hemisynthesis is of significant importance.

Synthesis of intramolecular cross-coupling analogues of forskolin

A ring distortion strategy was applied to the synthesis of a series of intramolecular cross-coupled analogues of forskolin 1. Treatment with palladium acetate, forskolin underwent an intramolecular cross-coupling reaction to generate a novel cycloalkene ether 2 in 85% yield. Under the same conditions, a series of forskolin ester analogues 4a-4d were prepared from 1-OH ester derivatives of forskolin 3a-3d in 85-93% yields. Treating cycloalkene ether 2 with aryl iodides in the presence of a palladium catalyst afforded Z-isomers arylation products 5a-5e in a stereoselective manner in 70-85% yields.

Synthesis and docking calculations of tetrafluoronaphthalene derivatives and their inhibition profiles against some metabolic enzymes

Syntheses of tetrahydroepoxy, O-allylic, O-prenylic, and O-propargylic tetrafluoronaphthalene derivatives, starting from 1-bromo-2,3,4,5,6-pentafluorobenzene, are reported here for the first time. The O-substituted tetrafluoronaphthalene derivatives were designed and also synthesized via a one-pot nucleophilic substitution reaction in excellent yields, whereas the tetrafluorotetrahydroepoxynaphthalene derivate was synthesized via a reduction reaction in excellent yield. The chemical structures of all the synthesized molecules were characterized by nuclear magnetic resonance, infrared spectroscopy, and high-resolution mass spectrometry techniques. In this study, a series of novel tetrafluoronaphthalene derivatives (2, 2a, 4-6) was tested toward several enzymes including α-glucosidase, acetylcholinesterase (AChE), and human carbonic anhydrase I and II (hCA I/II). The tetrafluoronaphthalene derivatives 2, 2a, and 4-6 showed IC₅₀ and K_i values in the range of 0.83-1.27 and 0.71-1.09 nM against hCA I, 1.26-1.85 and 1.45-5.31 nM against hCA II, 39.02-56.01 and 20.53-56.76 nM against AChE, and 15.27-34.12 and 22.58-30.45 nM against α-glucosidase, respectively. Molecular docking calculations were made to determine the biological activity values of the tetrafluoronaphthalene derivatives against the enzymes. After the calculations, ADME/T analysis was performed to examine the effects on human metabolism. Finally, these compounds had antidiabetic and anticholinesterase potentials.