Suramin inhibits SARS-CoV-2 nucleocapsid phosphoprotein genome packaging function.

The coronavirus disease 2019 (COVID-19) pandemic is fading, however its etiologic agent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues posing - despite the availability of licensed vaccines - a global health threat, due to the potential emergence of vaccine-resistant SARS-CoV-2 variants. This makes the development of new drugs against COVID-19 a persistent urgency and sets as research priority the validation of novel therapeutic targets within the SARS-CoV-2 proteome. Among these, a promising one is the SARS-CoV-2 nucleocapsid (N) phosphoprotein, a major structural component of the virion with indispensable role in packaging the viral genome into a ribonucleoprotein (RNP) complex, which also contributes to SARS-CoV-2 innate immune evasion by inhibiting the host cell type-I interferon (IFN-I) response.

Potentiometric Sensing of Nonsteroidal Painkillers by Acyclic Squaramide Ionophores.

We report here a small library of a new type of acyclic squaramide receptors (-) as selective ionophores for the detection of ketoprofen and naproxen anions (KF and NS, respectively) in aqueous media. H NMR binding studies show a high affinity of these squaramide receptors toward KF and NS, suggesting the formation of H-bonds between the two guests and the receptors through indole and -NH groups. Compounds - have been tested as ionophores for the detection of KF and NS inside solvent PVC-based polymeric membranes.

The role of indolyl substituents in squaramide-based anionophores.

A new family of squaramide-based anionophores (L1-L8) have been synthesised and fully characterised with the aim to investigate the effect of indolyl substituents on their anion binding and transmembrane transport properties. L1, L2, L6, and L8, bearing a 7-indolyl/indol-7-yl moiety as the substituent, were found to be the most efficient of the series in binding chloride with high stability constants. L1, L6, and L8 were also found to be the most potent anionophores of the series, able to mediate transmembrane anion transport.

Discovery of 2-Phenylquinolines with Broad-Spectrum Anti-coronavirus Activity.

A selection of compounds from a proprietary library, based on chemical diversity and various biological activities, was evaluated as potential inhibitors of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in a phenotypic-based screening assay. A compound based on a 2-phenylquinoline scaffold emerged as the most promising hit, with EC and CC values of 6 and 18 μM, respectively. The subsequent selection of additional analogues, along with the synthesis of ad hoc derivatives, led to compounds that maintained low μM activity as inhibitors of SARS-CoV-2 replication and lacked cytotoxicity at 100 μM.

Natural Compounds Inhibit SARS-CoV-2 nsp13 Unwinding and ATPase Enzyme Activities.

SARS-CoV-2 infection is still spreading worldwide, and new antiviral therapies are an urgent need to complement the approved vaccine preparations. SARS-CoV-2 nps13 helicase is a validated drug target participating in the viral replication complex and possessing two associated activities: RNA unwinding and 5'-triphosphatase. In the search of SARS-CoV-2 direct antiviral agents, we established biochemical assays for both SARS-CoV-2 nps13-associated enzyme activities and screened both and a small in-house library of natural compounds.

Zika virus NS2A inhibits interferon signaling by degradation of STAT1 and STAT2.

The Interferon (IFN) response is crucial to restrain pathogenic infections. Investigations into flavivirus-host interactions reported that the high virulence is linked to innate immune evasion. Zika Virus (ZIKV) has developed diversified strategies to evade the innate immune system.

Switching-On Fluorescence by Copper (II) and Basic Anions: A Case Study with a Pyrene-Functionalized Squaramide.

The new symmetric acyclic -bis(1-pyrenyl) squaramide () functionalized with the pyrene moiety as a fluorogenic fragment has been designed and its ability to selectively detect specific anions and metals investigated. selectively binds Cl both in solution (DMSO 0.5% HO and MeCN) and in the solid state, and allows to selectively detect Cu in MeCN with the formation of a 2:1 metal-receptor complex, with a green intense emission appreciable by naked eye under the UV lamp.