Understanding the Scope of Feist-Bénary Furan Synthesis: Chemoselectivity and Diastereoselectivity of the Reaction Between α-Halo Ketones and β-Dicarbonyl Compounds

A silver-mediated radical process of β-keto sulfones for the synthesis of 2,3-diacyl furans

A facile and efficient method for constructing 2,3-diacyl trisubstituted furans via a silver-mediated radical process of β-keto sulfones is developed. The reaction mechanism has been carefully investigated, revealing that the transformation proceeds through a radical pathway, leading to moderate to good yields of desired products.

Reactivity and Stability of (Hetero)Benzylic Alkenes via the Wittig Olefination Reaction

Wittig olefination at hetero-benzylic positions for electron-deficient and electron-rich heterocycles has been studied. The electronic effects of some commonly used protective groups associated with the N-heterocycles were also investigated for alkenes obtained in the context of the widely employed Wittig olefination reaction. It was observed that hetero-benzylic positions of the pyridine, thiophene and furan derivatives were stable after Wittig olefination. Similarly, electron-withdrawing groups (EWGs) attached to N-heterocycles (indole and pyrrole derivatives) directly enhanced the stability of the benzylic position during and after Wittig olefination, resulting in the formation of stable alkenes. Conversely, electron-donating group (EDG)-associated N-heterocycles boosted the reactivity of benzylic alkene, leading to lower yields or decomposition of the olefination products.

Design, Synthesis and Anticonvulsant Activity of Cinnamoyl Derivatives of 3,4,6,7,8,9-hexahydrodibenzo[b,d]furan-1-(2H)-one Oxime

BACKGROUND

Epilepsy continues to be a significant global health problem and the search for new drugs for its treatment remains an urgent task. 5-HT2 and GABAA-receptors are among promising biotargets for the search for new anticonvulsants.

METHODS

New potential 5-HT2 and GABAA ligands in the series of substituted cinnamoyl derivatives of 3,4,6,7,8,9-hexahydrodibenzo[b,d]furan-1-(2H)-one oxime were designed using pharmacophore model and molecular docking analysis. The synthesis of new compounds was carried out from 3,4,6,7,8,9-hexahydrodibenzo[b,d]furan-1(2H)-one oxime and substituted cinnamoyl chlorides. The anticonvulsant activity of new substances has been established using the maximal electroshock seizure test.

RESULTS

Several synthesized substituted cinnamoyl derivatives of 3,4,6,7,8,9-hexahydrodibenzo [b,d]furan-1-(2H)-one oxime significantly reduced the severity of convulsive manifestations and completely prevented the death of animals after MES. The structure-activity relationship was investigated. The most effective compound was found to be GIZH-348 (1g) (3,4,6,7,8,9-hexahydrodibenzo[ b,d]furan-1(2Н)-one О-(4-chlorophenyl)acryloyl)oxime) at the doses of 10-20 mg/kg.

CONCLUSION

Molecular and pharmacophore modelling methods allowed us to create a new group of substituted cinnamoyl derivatives of 3,4,6,7,8,9-hexahydrodibenzo[b,d]furan-1-(2H)-one oxime with anticonvulsant activity.

Titanium-Mediated Domino Cross-Coupling/Cyclodehydration and Aldol-Addition/Cyclocondensation: Concise and Regioselective Synthesis of Polysubstituted and Fused Furans

Titanium enolates, in situ-generated from readily available ketones and titanium tetraisopropoxide, undergo domino cross-coupling/cyclodehydration or domino Aldol-addition/cyclocondensation with α-chloroketones to provide synthetically valuable furan derivatives. The domino process tolerates a variety of cyclic and acyclic ketones and chloroketones, producing polysubstituted furans and bi-, tri-, and tetracyclic fused furans.

Discovery of Novel Inhibitors of Uridine Diphosphate-N-Acetylenolpyruvylglucosamine Reductase (MurB) from Pseudomonas aeruginosa, an Opportunistic Infectious Agent Causing Death in Cystic Fibrosis Patients

Pseudomonas aeruginosa is of major concern for cystic fibrosis patients where this infection can be fatal. With the emergence of drug-resistant strains, there is an urgent need to develop novel antibiotics against P. aeruginosa. MurB is a promising target for novel antibiotic development as it is involved in the cell wall biosynthesis. MurB has been shown to be essential in P. aeruginosa, and importantly, no MurB homologue exists in eukaryotic cells. A fragment-based drug discovery approach was used to target Pa MurB. This led to the identification of a number of fragments, which were shown to bind to MurB. One fragment, a phenylpyrazole scaffold, was shown by ITC to bind with an affinity of K_d = 2.88 mM (LE 0.23). Using a structure guided approach, different substitutions were synthesized and the initial fragment was optimized to obtain a small molecule with K_d = 3.57 μM (LE 0.35).

Synthesis, In Vitro Antitumor Activity and Molecular Mechanism of Novel Furan Derivatives and their Precursors

BACKGROUND

Compounds featuring furan nucleus exhibit diverse biological properties. Lots of furan derivatives have been explored as pharmaceutical compounds. Hence it is of great interest to explore furan derivatives and their precursors as antitumor agents.

OBJECTIVE

A series of novel furan derivatives and their precursors (1-36) were synthesized from α-haloketones and β-dicarbonyl compounds.

METHODS

The reactions between β-dicarbonyl compounds and α-haloketones under basic conditions produced tricarbonyls or dihydrofurans, which were then condensed into their corresponding furan products. Their potential antiproliferative activity in vitro against two human tumor cell lines-cervical (HeLa) and colorectal (SW620) was evaluated using CCK-8 assay. Compounds 1 and 24 were selected for Western blot analysis.

RESULTS

Pronounced anti-proliferative effect in the micromolar level was observed for compounds (1, 4, 17, 20, 21, 24, 27, 31 and 32) in HeLa cells, with their IC50 values ranging from 0.08 to 8.79μM. Additionally, furan compounds (24, 26, 32 and 35) had moderate to potent anti-proliferative activity against the SW620 cell line. Furthermore, the possible targets of these compounds were explored by Western blot analysis. The results indicated that the candidates (compounds 1 and 24) exhibited excellent antiproliferative activity, which may be mediated by promoting the activity of PTEN to suppress PI3K/Akt and Wnt/β-catenin signaling.

CONCLUSION

Most of the furan derivatives and their precursors reported herein exhibited moderate to excellent anti-proliferative activity against HeLa cell line and/or SW620 cell line. Compounds 1 and 24, as well as their analogues may be developed as promising anti-cancer agents.

Synthesis of 2-alkenylfurans via a Ag(i)-catalyzed tandem cyclization/cross-coupling reaction of enynones with iodonium ylides

A silver(i)-catalyzed tandem cyclization/cross-coupling reaction of enynones with iodonium ylides to construct carbon-carbon double bonds has been developed. The strategy provides a novel method for the synthesis of 2-alkenylfurans. This is the first cross-coupling reaction between metal-carbene complexes and iodonium ylides.

Design, synthesis and biological activities of pyrrole-3-carboxamide derivatives as EZH2 (enhancer of zeste homologue 2) inhibitors and anticancer agents

A novel series of pyrrole-3-carboxamides targeting EZH2 have been designed and synthesized. The structure–activity relationships were summarized by combining within vitrobiological activity assay and docking results.

Biomimetic synthesis of the bisindole framework present in sciodole, an alkaloid fromTricholoma sciodes

The unique bisindole bond present in the alkaloid sciodole can be forged by amination of an azafulvene, validating a biosynthetic hypothesis.