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The rise of drug resistance to antivirals poses a significant global concern for public health; therefore, there is a pressing need to identify novel compounds that can effectively counteract strains resistant to current antiviral treatments. In light of this, researchers have been exploring new approaches, including the investigation of natural compounds as alternative sources for developing potent antiviral therapies. Thus, this work aimed to evaluate the antiviral properties of the organic-soluble fraction of a root exudate derived from the tomato plant Solanum lycopersicum in the context of herpesvirus infections. Our findings demonstrated that a root exudate from Solanum lycopersicum exhibits remarkable efficacy against prominent members of the family Herpesviridae, specifically herpes simplex virus type 1 (HSV-1) (EC50 25.57 µg/mL, SI > 15.64) and human cytomegalovirus (HCMV) (EC50 9.17 µg/mL, SI 32.28) by inhibiting a molecular event during the herpesvirus replication phase. Moreover, the phytochemical fingerprint of the Solanum lycopersicum root exudate was characterized through mass spectrometry. Overall, these data have unveiled a novel natural product with antiherpetic activity, presenting a promising and valuable alternative to existing drugs. [ABSTRACT FROM AUTHOR]

Pd-catalyzed aminocarbonylation in the presence of Xantphos as a ligand was used to transform lactam-, lactone-, and thiolactone-derived triflates into N-methoxy-N-methyl or morpholine Weinreb amides. The method could also be applied to synthesize dienones in which one of the double bonds is embedded in a heterocyclic moiety, as useful substrates for Nazarov cyclization.

Three different procedures are compared to obtain properly substituted divinyl ketones in which one of the double bonds is embedded in a five-membered heterocyclic structure and therefore suitable to produce cyclopenta-fused pyrrole, derivatives by the acid-catalyzed Nazarov reaction. A convergent procedure base on the umpolung to a vinylstannane gave acceptable yields of the divinyl ketone, which forms a key intermediate in the synthesis of roseophilin.

Reporting on the torquoselectivity in the cyclization of 2-substituted five-membered azacycle and 2- and 4-substituted six-membered oxacycle derivatives. The reaction is highly diastereoselective with 2-substituted five-membered lactam derivatives 11a and 11b and leads to cis disubstituted cyclopenta-fused pyrrolines 13a and 13b, respectively.

The reaction between 1-metalated 1-ethoxy 1,3-dienes and electrophiles yields (E)-1-substituted 1-ethoxy 1,3-dienes. These alpha-substituted alkoxy dienes produce alpha, beta-unsaturated carbonyl compounds on acidic hydrolysis via a reaction pathway involving carbanionic intermediates. Use of crotonaldehyde as an electrophile produces an addition product, which on hydrolysis, yields three products depending on experimental conditions.

Abstract Background Strigolactones (SLs) are recently identified plant hormones modulating root and shoot branching. Besides their endogenous role within the producing organism, SLs are also key molecules in the communication of plants with arbuscular mycorrhizal (AM) fungi and parasitic weeds. In fact SLs are exuded into the rhizosphere where they act as a host-derived signal, stimulating the germination of the seeds of parasitic plants which would not survive in the absence of a host root to colonize. Similarly, their perception by AM fungi causes extensive hyphal branching; this is a prerequisite for effective root colonization, since it increases the number of potential contact points with the host surface. In spite of the crucial and multifaceted biological role of SLs, there is no information on the receptor(s) which bind(s) such active molecules, neither in the producing plants, or in parasitic weeds or AM fungi. Results In this work, we applied homology modelling techniques to investigate the structure of the protein encoded by the gene Dwarf14, which was first identified in rice as conferring SLs insensitivity when mutated. The best sequence identity was with bacterial RsbQ. Both proteins belong to the superfamily of alpha/beta-fold hydrolases, some members of which play a role in the metabolism or signalling of plant hormones. The Dwarf14 (D14) structure was refined by means of molecular dynamics simulations. In order to support the hypothesis that D14 could be an endogenous SLs receptor, we performed docking experiments with a natural ligand. Conclusions It is suggested that D14 interacts with and thereby may act as a receptor for SLs in plants. This hypothesis offers a starting point to experimentally study the mechanism of its activity in vivo by means of structural, molecular and genetic approaches. Lastly, knowledge of the putative receptor structure will boost the research on analogues of the natural substrates as required for agricultural applications.

An approach for the synthesis of functionalized trienes and regioselective formation of medium-ring lactones is discussed. Both reactions involves intramolecular Diels-Alder reaction which generate the macrocyclic rings. The reaction is performed at varying temperature and solvents to determine both the regioselectivity and stereoselectivity of the synthetic pathway. H nuclear magnetic spectra of the reaction is discussed.

3-ethoxyhexa-3,5-dien-1-ol is prepared from a reaction between an electrophile, ethylene oxide and an alpha-metalated alkoxy diene which involves an epoxide ring opening. Synthesis of 2- and 2,6-disubstituted tetrahydro-4H-pyran-4-ones involves these alpha-substituted alkoxy dienes as intermediates. Propylene oxide yields a mixture of cis and trans compounds. 1H NMR and gas chromatography analyses are employed to calculate the cis-trans ratio.

Answers to some queries such as, whether the presence of the N atom in the cyclic moiety of conjugated triene is necessary to attain electrocyclization under certain assumption are presented. Demonstration of the synthetic usefulness of the methodology, for the diasteroselective synthesis of cyclopenta-fused heterocyclic compounds, is presented.

Research has been conducted on palladium-catalyzed cross- coupling reactions of alpha-alkoxyboronates with lactam-derived vinyl triflates. The methodology developed for the preparation of azacyclic compounds is described.