Arthropod-borne viruses (arboviruses) are a severe public health problem worldwide, consisting of a significant part of all the emerging infectious diseases. It is estimated that arboviruses infect hundreds of millions of people globally each year, resulting in several thousand deaths. Despite their clear health threat, there are no prophylactic or pharmacological therapies available for most of them. Control of arbovirus infections is beyond pharmacological options; handling the larvae of mosquitos is an important and successful strategy, although currently available insecticides and larvicides are already associated with resistance. Therefore, searching for new strategies to prevent arbovirus infection is urgent and necessary. Marine organisms are an excellent source for structurally novel compounds due to their unique secondary metabolism, with outstanding antiviral and larvicidal activities. In the present review, we explored the ability of various marine natural products (MNPs) such as indole derivatives, diketopiperazines, scequinadoline A, cyclohexadepsipeptides, and others, to act as both antiviral and larvicidal, in an attempt to highlight their structure activity potential against the most relevant arboviruses affecting the human health. Arthropodborne Arthropod borne (arboviruses worldwide diseases year deaths threat them options strategy resistance Therefore necessary metabolism activities review MNPs (MNPs derivatives diketopiperazines A cyclohexadepsipeptides others

This work describes the first determination of the absolute configuration (AC) of (−)-cubebin by means of electronic circular dichroism (ECD), supported by quantum chemical calculations. The comparison of experimental ECD with the corresponding quantum chemical prediction for the proper diastereoisomer resulted in the definitive assignment of the AC of the naturally occurring (−)-cubebin as (8R,8aR,9S). The challenging determination of the relative configuration (RC) of cubebin based only on experimental nuclear magnetic resonance (NMR) methods is stressed. Computation of the 13C and 1H NMR chemical shifts for all the possible diastereoisomers leads to values of mean absolute error and root mean square deviation that do not allow distinguishing among them. Thus, errors in stereochemical determination can easily occur even when using two-dimensional methods, which clearly demonstrate the complexity of this special case. To determine the RC of this bioactive natural compound with high level of confidence, it was necessary to combine the DP4+ method with X-ray crystallography. Therefore, employing the commonly used empirical methods to determine the AC of (−)-cubebin can easily lead to misassignment of its stereochemistry.

We reported experimental and theoretical investigation of conformers of 1,2,3-triazole derivatives, substances of exclusively synthetic origin, subject of extensive studies, because of several biological properties, such as antiviral, antimicrobial and antileishmaniasis. We reported molecular/supramolecular X-ray structures of antiophidian compounds I and II. For I and II there are two crystallographic different molecules in the unit cell (A and B). To explore the causes of the similarities in the compound’s crystal structures, intermolecular interactions were explored using the Hirshfeld surface as the fingerprint plots. In addition, density functional theory (DFT) calculations were carried out at the ωB97x-D/6-31G(d,p)-PCM-CHCl3 level aiming to contribute to the interpretation of the experimental data and complement the experimental findings. Two structures named 2A and 5B were found in good agreement with the respective X-ray solid state ones (A and B). Theoretical 1H nuclear magnetic resonance (NMR) spectra calculated for 5B rotated structure (torsion angles deviation around 40° to 90°) was in fine agreement with experimental results (in CDCl3) indicating that the solution molecular structure is considerably different from optimized equilibrium geometries and solid-state structure. Therefore, care is needed when using X-ray structures or DFT geometries to model interaction of drugs with biological targets since significant conformational changes may take place in solution.