3-Aryltetronic Acids: Efficient Preparation and Use as Precursors for Vulpinic Acids

Synthesis, Modeling, and Biological Evaluation of Anti-Tubulin Indole-Substituted Furanones

Due to the central role of tubulin in various cellular functions, it is a validated target for anti-cancer therapeutics. However, many of the current tubulin inhibitors are derived from complex natural products and suffer from multidrug resistance, low solubility, toxicity issues, and/or the lack of multi-cancer efficacy. As such, there is a continued need for the discovery and development of new anti-tubulin drugs to enter the pipeline. Herein we report on a group of indole-substituted furanones that were prepared and tested for anti-cancer activity. Molecular docking studies showed positive correlations between favorable binding in the colchicine binding site (CBS) of tubulin and anti-proliferative activity, and the most potent compound was found to inhibit tubulin polymerization. These compounds represent a promising new structural motif in the search for small heterocyclic CBS cancer inhibitors.

Tandem Reactions Based on the Cyclization of Carbon Dioxide and Propargylic Alcohols: Derivative Applications of α-Alkylidene Carbonates

As a well-known greenhouse gas, carbon dioxide (CO2) has attracted increasing levels of attention in areas of energy, environment, climate, etc. Notably, CO2 is an abundant, nonflammable, and renewable C1 feedstock in view of chemistry. Therefore, the transformation of CO2 into organic compounds is an extremely attractive research topic in modern green and sustainable chemistry. Among the numerous CO2 utilization methods, carboxylative cycloaddition of CO2 into propargylic alcohols is an ideal route due to the corresponding products, α-alkylidene cyclic carbonates, which are a series of highly functionalized compounds that supply numerous potential methods for the construction of various synthetically and biologically valuable agents. This cyclization reaction has been intensively studied and systematically summarized, in the past years. Therefore, attention has been gradually transferred to produce more derivative compounds. Herein, the tandem reactions of this cyclization with hydration, amination, alcoholysis, and isomerization to synthesize α-hydroxyl ketones, oxazolidinones, carbamates, unsymmetrical carbonates, tetronic acids, ethylene carbonates, etc. were systematically reviewed.

Discovery of an indole-substituted furanone with tubulin polymerization inhibition activity

Analogs of diarylpyrrolinone lead compound 1 were prepared and tested for anti-proliferative activity in U-937 cancer cells. Alterations of 1 focused on modifying the two nitrogen atoms: a) the pyrrolinone nitrogen atom was substituted with a propyl group or replaced with an oxygen atom (furanone), and b) the substituents on the indole nitrogen were varied. These changes led to the discovery of a furanone analog 3b with sub-micromolar anti-cancer potency and tubulin polymerization inhibition activity.

Synthesis and Bio-Evaluation of Natural Butenolides-Acrylate Conjugates

A series of novel 3-aryl-4-hydroxy-2(5H) furanone-acrylate hybrids were designed and synthesized based on the natural butenolides and acrylates scaffolds. The structures of the prepared compounds were characterized by ¹H-NMR, ¹³C-NMR and electrospray ionization mass spectrometry (ESI-MS), and the bioactivity of the target compounds against twelve phytopathogenic fungi was investigated. The preliminary in vitro antifungal activity screening showed that most of the target compounds had moderate inhibition on various pathogenic fungi at the concentration of 100 mg·L⁻¹, and presented broad-spectrum antifungal activities. Further studies also indicated that compounds 7e and 7k still showed some inhibitory activity against Pestallozzia theae, Sclerotinia sclerotiorum and Gibberella zeae on rape plants at lower concentrations, which could be optimized as a secondary lead for further research.

Synthesis of tetronic acids from propargylic alcohols and CO2

A direct and practical synthesis of important tetronic acids from easily available propargylic alcohols and carbon dioxide is reported for the first time. This transition-metal-free transformation features high atom- and step-economy, mild reaction conditions, good functional group tolerance and high yield. Preliminary mechanistic studies suggest that the reaction proceeds via cyclization to give alkylidene cyclic carbonate, ring-opening and re-cyclization processes.

Thermodynamically driven, syn-selective vinylogous aldol reaction of tetronamides

A stereoselective vinylogous aldol reaction of N-monosubstituted tetronamides with aldehydes is described.

Design and Synthesis of a New Class of Twin-Chain Amphiphiles for Self-Assembled Monolayer-based Electrochemical Biosensor Applications

A new class of twin-chain hydroxyalkylthiols (mercaptoalkanols) featuring a nearly constant cross-section and the potential for modification of one or both termini are available with complete regioselectivity through Pd-mediated couplings of benzene diiododitriflate, including an example of a previously unreported coupling to generate an ortho-substituted arene bis acetic acid. Self-assembled monolayers (SAMs) prepared from the new amphiphiles demonstrate improved stability in an electrochemical sensor system compared with monolayers prepared from analogous single chain thiols.

Tetramic and tetronic acids as scaffolds in bioinorganic and bioorganic chemistry

Tetramic and tetronic acids are naturally occurring molecules with a variety of biological activities. In this review article, we present the general strategies for the synthesis of these compounds and we reveal the functionalized groups that are responsible for their properties. We also set out their coordinating modes with up-to-date bibliographical references.

Tetramic and tetronic acids as scaffolds in bioinorganic and bioorganic chemistry

Tetramic and tetronic acids are naturally occurring molecules with a variety of biological activities. In this review article, we present the general strategies for the synthesis of these compounds and we reveal the functionalized groups that are responsible for their properties. We also set out their coordinating modes with up-to-date bibliographical references.