Kaurenoic acid is a potent inhibitor of SARS-CoV-2 RNA synthesis, virion assembly, and release .

Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is responsible for the coronavirus disease 2019 (COVID-19) pandemic, continues to pose global health challenges despite the availability of approved vaccines and antiviral drugs. The emergence of new variants of SARS-CoV-2 and ongoing post-COVID complications necessitate continuous exploration of effective treatments. Kaurenoic acid (KA) is a tetracyclic diterpenoid isolated from plants of the genus and has been previously recognized for its anti-inflammatory, antibacterial, antifungal, and antitumor properties.

Bothropstoxins I and II as potent phospholipase A2 molecules from Bothrops jararacussu to impair hepatitis C virus infection.

Hepatitis C virus (HCV) (now classified Hepacivirus hominis) that infects an estimated 50 million individuals worldwide and causes chronic liver disease. The current treatment for infected patients primarily relies on direct-acting antivirals (DAAs). However, this treatment is marked by its high cost, numerous side effects, and documented instances of antiviral resistance.

Investigation of the Influence of the Extraction System and Seasonality on the Pharmacological Potential of Leaves.

The chemical complexity of natural products, such as (Kunth) DC. plant, presents a challenge when extracting and identifying bioactive compounds. This study investigates the impact of different extraction systems and seasonal variations on the chemical profile and pharmacological potential of leaves using NMR spectroscopy for chemical analysis and canonical correlation analysis (CCA) for bioactivity correlation.

Brazilian red propolis reduces the adhesion of oral biofilm cells and the Toxoplasma gondii intracellular proliferation.

Infectious diseases remain as a significant cause of thousands of deaths annually worldwide. Therefore, this study aimed to investigate the antimicrobial and antiparasitic activity of the crude hydroalcoholic extract and compounds isolated from Brazilian Red Propolis (BRP) against oral pathogens and Toxoplasma gondii, using in vitro, in vivo and in silico approaches. Antimicrobial and synergistic activities were determined using the broth dilution method and the checkerboard assay, respectively.

Exploring antiviral and antiparasitic activity of gold N-heterocyclic carbenes with thiolate ligands.

Gold(I) N-heterocyclic carbenes have been explored for their therapeutic potential against several diseases. Neglected tropical diseases, including leishmaniasis, Chagas disease, and viral infections, such as zika, mayaro, and chikungunya, urgently require new treatment options. The emergent SARS-CoV-2 also demands significant attention.

Development and validation of Mayaro virus with luciferase reporter genes as a tool for antiviral assays.

Arboviruses are etiological agents in an extensive group of emerging diseases with great clinical relevance in Brazil, due to the wide distribution of their vectors and the favorable environmental conditions. Among them, the Mayaro virus (MAYV) has drawn attention since its emergence as the etiologic agent of Mayaro fever, a highly debilitating disease. To study viral replication and identify new drug candidates, traditional antiviral assays based on viral antigens and/or plaque assays have been demonstrating low throughput, making it difficult to carry out larger-scale assays.

Influence of diimine bidentate ligand in the nitrosyl and nitro terpyridine ruthenium complex on the HSA/DNA interaction and antiviral activity.

Nitric oxide (NO) acts in different physiological processes, such as blood pressure control, antiparasitic activities, neurotransmission, and antitumor action. Among the exogenous NO donors, ruthenium nitrosyl/nitro complexes are potential candidates for prodrugs, due to their physicochemical properties, such as thermal and physiological pH stability. In this work, we proposed the synthesis and physical characterization of the new nitro terpyridine ruthenium (II) complexes of the type [Ru(L)(NO)(tpy)]PF where tpy = 2,2':6',2″-terpyridine; L = 3,4-diaminobenzoic acid (bdq) or o-phenylenediamine (bd) and evaluation of influence of diimine bidentate ligand NH.

Discovery and structural optimization of a new series of N-acyl-2-aminobenzothiazole as inhibitors of Zika virus.

Zika virus infection is associated to severe diseases such as congenital microcephaly and Zika fever causing serious harm to humans and special concern to health systems in low-income countries. Currently, there are no approved drugs against the virus, and the development of anti-Zika virus drugs is thus urgent. The present investigation describes the discovery and hit expansion of a N-acyl-2-aminobenzothiazole series of compounds against Zika virus replication.

Natural Compounds as Non-Nucleoside Inhibitors of Zika Virus Polymerase through Integration of In Silico and In Vitro Approaches.

Although the past epidemic of Zika virus (ZIKV) resulted in severe neurological consequences for infected infants and adults, there are still no approved drugs to treat ZIKV infection. In this study, we applied computational approaches to screen an in-house database of 77 natural and semi-synthetic compounds against ZIKV NS5 RNA-dependent RNA-polymerase (NS5 RdRp), an essential protein for viral RNA elongation during the replication process. For this purpose, we integrated computational approaches such as binding-site conservation, chemical space analysis and molecular docking.

Roles of Bothrops jararacussu toxins I and II: Antiviral findings against Zika virus.

Zika virus is the etiologic agent of Zika fever, and has been previously associated with cases of microcephaly, drawing the attention of the health authorities worldwide. However, no vaccine or antiviral are currently available. Phospholipases A (PLA) isolated from snake venoms have demonstrated antiviral activity against several viruses.