Enantiomeric 4'-truncated 6'-fluoro-3-deazaneplanocin and its 3-bromo derivative: Synthesis and antiviral properties, including Ebola and Marburg

EZH2 serves as a promising therapeutic target for fibrosis

Fibrosis affects the function of many organs and tissues, and its persistent development can lead to tissue sclerosis and cancer, even leading to death further. Recent studies suggested that enhancer of zeste homolog 2 (EZH2), a major regulator of epigenetic repression, played an important role in the occurrence and development of fibrosis through gene silencing or transcriptional activation. As the most studied and powerful pro-fibrotic cytokine closely related to EZH2, TGF-β1 was primarily involved in the regulation of fibrosis along with the typical Smads and non-Smads signaling pathways. In addition, EZH2 inhibitors demonstrated inhibitory effects in several types of fibrosis. This review summarized the relationship underlying the action of EZH2, TGF-β1/Smads, and TGF-β1/non-Smads with fibrosis and described the research progress of EZH2 inhibitors in the treatment of fibrosis.

2- and 3-Fluoro-3-deaza-1',6'-isoneplanocin: Synthesis and antiviral properties (including Ebola and Marburg)

To extend the antiviral properties of 2- and 3-fluoro-3-deazaneplanocins into the evolving 3-deaza-1',6'-isoneplanocin library, 2- (11) and 3-fluoro-1',6'-iso-3-deazaneplanocin A (12) have been explored. The requisite synthesis began with an Ullmann reaction by coupling of a protected cyclopentenyl iodide with either 2-fluoro- or 3-fluoro-3-deazaadenine. Target 12 displayed significant activity towards 5 viruses (μM): H1N1 (EC₅₀ < 0.36, CC₅₀ > 357, SI > 1000), hepatitis B virus (EC₅₀ 1.28, CC₅₀ > 357, SI > 279), norovirus (EC₅₀ 0.64, CC₅₀ > 357, SI > 558), Ebola (EC₅₀ < 0.1, CC₅₀ > 100, SI > 1000), and Marburg (EC₅₀ < 0.1, CC₅₀ > 100, SI > 1000). On the other hand, while 11 showed limited antiviral effects, its toxicity was significant, precluding any further usefulness.

Photocatalytic Defluorinative Three-Component Reaction of α-Trifluoromethyl Alkenes, Alkenes, and Sodium Sulfinates: Synthesis of Monofluorocyclopentenes

A photocatalytic three-component reaction of α-trifluoromethyl alkenes, electron-rich alkenes, and sodium sulfinates for the synthesis of gem-difluoroalkenes in a radical/polar crossover manner was developed. Due to the strong electron-withdrawing nature of the sulfonyl group, the resultant gem-difluoroalkenes can be converted into various monofluorocyclopentenes via intramolecular base-mediated S_NV reactions in one pot.

New Derivatives of 5-Substituted Uracils: Potential Agents with a Wide Spectrum of Biological Activity

Pyrimidine nucleoside analogues are widely used to treat infections caused by the human immunodeficiency virus (HIV) and DNA viruses from the herpes family. It has been shown that 5-substituted uracil derivatives can inhibit HIV-1, herpes family viruses, mycobacteria and other pathogens through various mechanisms. Among the 5-substituted pyrimidine nucleosides, there are not only the classical nucleoside inhibitors of the herpes family viruses, 2'-deoxy-5-iodocytidine and 5-bromovinyl-2'-deoxyuridine, but also derivatives of 1-(benzyl)-5-(phenylamino)uracil, which proved to be non-nucleoside inhibitors of HIV-1 and EBV. It made this modification of nucleoside analogues very promising in connection with the emergence of new viruses and the crisis of drug resistance when the task of creating effective antiviral agents of new types that act on other targets or exhibit activity by other mechanisms is very urgent. In this paper, we present the design, synthesis and primary screening of the biological activity of new nucleoside analogues, namely, 5'-norcarbocyclic derivatives of substituted 5-arylamino- and 5-aryloxyuracils, against RNA viruses.

Synthesis of Truncated Carbocyclic Nucleosides Using 5'-Deoxy-5'-Heteroarylsulfonylnucleosides

This article describes the detailed protocol for the synthesis of "truncated" carbocyclic nucleosides with a cyclopentene core and without a 4'-hydroxymethyl group. The synthesis was performed using 5'-deoxy-5'-heteroarylsulfonylnucleosides, which were prepared by the 5'-O-mesylation of the appropriately protected nucleosides, followed by a nucleophilic substitution with heteroarylthiols and the oxidation of the resulting 5'-S-heteroaryl-5'-thionucleosides. The treatment of the 5'-deoxy-5'-heteroarylsulfonylnucleosides with 1,8-diazabicyclo[5.4.0]undec-7-ene affords the truncated carbocyclic nucleosides, presumably via a domino reaction involving the α-deprotonation of the heteroarylsulfone, elimination of the nucleobase, formation of an α,β-unsaturated sulfone, Michael addition of the nucleobase to the α,β-unsaturated sulfone, and an intramolecular Julia-Kocienski reaction. This protocol would be useful for the short-step synthesis of biologically active carbocyclic nucleosides. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Preparation of 5'-deoxy-5'-heteroarylsulfonylnucleosides Basic Protocol 2: Synthesis of truncated carbocyclic nucleosides.

Fluorinated Nucleosides: Synthesis, Modulation in Conformation and Therapeutic Application

Over the last twenty years, fluorination on nucleoside has established itself as the most promising tool to use to get biologically active compounds that could sustain the clinical trial by affecting the pharmacodynamics and pharmacokinetic properties. Due to fluorine's inherent unique properties and its judicious introduction into the molecule, makes the corresponding nucleoside metabolically very stable, lipophilic, and opens a new site of intermolecular binding. Fluorination on various nucleosides has been extensively studied as a result, a series of fluorinated nucleosides come up for different therapeutic uses which are either approved by the FDA or under the advanced stage of the clinical trial. Here in this review, we are summarizing the latest development in the chemistry of fluorination on nucleoside that led to varieties of new analogs like carbocyclic, acyclic, and conformationally biased nucleoside and their biological properties, the influence of fluorine on conformation, oligonucleotide stability, and their use in therapeutics.

Serendipitous One-Step Synthesis of Cyclopentene Derivatives from 5'-Deoxy-5'-heteroarylsulfonylnucleosides as Nucleoside-Derived Julia-Kocienski Reagents

A serendipitous one-step transformation of 5'-deoxy-5'-heteroarylsulfonylnucleosides into cyclopentene derivatives is reported. This unique transformation likely proceeds via a domino reaction initiated by α-deprotonation of the heteroaryl sulfone and subsequent elimination reaction to generate a nucleobase and an α,β-unsaturated sulfone that contains a formyl group. The Michael addition of the nucleobase to the α,β-unsaturated sulfone and the subsequent intramolecular Julia-Kocienski reaction eventually generate the cyclopentene ring. Heteroarylthio and acylthio groups can be incorporated into the cyclopentene core in place of the nucleobase by conducting this reaction in the presence of a heteroarylthiol and a thiocarboxylic acid, respectively. cis,cis-Trisubstituted cyclopentene derivatives are obtained as a single stereoisomer from ribonucleoside-derived Julia-Kocienski sulfones.