Access to Multisubstituted 2(5H)-Furanones Using Hydrogen Bonding-Promoted Ring-Closing Metathesis and Polyamine Workup

Synthesis of Phenanthrenes and 1-Hydroxyphenanthrenes via Aromatization-Assisted Ring-Closing Metathesis: toward Polynuclear Aromatic Hydrocarbons

This study presents an efficient synthetic strategy for phenanthrenes and 1-hydroxyphenanthrenes through aromatization-assisted ring-closing metathesis (RCM). It involves vinylation of 1-bromo-2-naphthaldehyde derivatives, Barbier allylation, and subsequent one-pot RCM/dehydration of the diene precursors to yield phenanthrene derivatives. Further, the corresponding keto analogues of diene precursors produce 1-hydroxyphenanthrenes through RCM and aromatization-driven keto-enol tautomerism. This pathway enables rapid access to a diverse array of functionalized phenanthrenes and 1-hydroxyphenanthrenes, including synthetically challenging derivatives containing both -OH and -OMe groups via the sequential construction of the terminal phenanthrene ring.

Furanone-functionalized benzothiazole derivatives: synthesis, in vitro cytotoxicity, ADME, and molecular docking studies

In the present study, a novel series of new furanone-based benzothiazole derivatives (4a-j) were synthesized from 4-(benzo[d]thiazol-2-yl)-4-oxobutanoic acid (3) as potential anticancer agents. In vitro cytotoxicity against three human cancer cell lines (A549, MCF7, and DUI45) revealed substantial activity. Di-substituted compound, 4i emerged as a promising anticancer compound which showed IC50 values of 7.2 ± 0.5, 6.6 ± 1.4, and 7.3 ± 0.1 µM against A549, MCF7, and DUI45 cell lines, respectively. Four compounds 4c, 4e, 4f, and 4i evaluated for their acute toxicity were found to be non-toxic on the two vital organs (liver and heart). Further, these compounds were found to be more efficient and less hepatotoxic in comparison to standard drug doxorubicin. Molecular docking studies carried out with VEGFR-2 revealed compounds 4a and 4i as potential VEGFR-2 kinase inhibitors. In silico ADME evaluation was carried out to estimate and predict drug-likeness. Compound 4i demonstrated the best ADME parameters. Based on the results of docking analyses, ADME, and in vitro cytotoxicity, compound 4i is identified as the lead compound for further development of anticancer agents.

Synthesis of amino acid derivatives of 5-alkoxy-3,4-dihalo-2(5H)-furanones and their preliminary bioactivity investigation as linkers

A series of amino acid derivatives are successfully synthesized via a metal-free C-N coupling reaction of 5-alkoxy-3,4-dihalo-2(5H)-furanones and amino acids. Their structures are well characterized with ¹H NMR, ¹³C NMR, ESI-MS and elemental analysis. As potential linkers of the 2(5H)-furanone unit with other drug moieties containing a hydroxyl or amino group, the effect of amino acids is investigated by comparison with other 2(5H)-furanone compounds by constructing C-O/C-S bonds. The preliminary results of the biological activity assay by the MTT method on a series of cancer cell lines in vitro reveal that the introduction of amino acids basically has no toxic effect. This can lead to these 2(5H)-furanone derivatives being further well-linked with other bioactive moieties with amino or hydroxy groups as expected. Thus, the biological activity assay gives a direction for the design of bioactive 2(5H)-furanones based on these amino acid linkers.