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

Aromatic amines are important intermediates in the industry to produce a wide array of products, and the reduction of aromatic nitro compounds is the main methodology for their preparation. Considering this fact, the objective of this review is to describe the development of sustainable methodologies for the reduction of aromatic nitro compounds for their respective amines from 2017 to 2020. Thus, throughout the text, the reaction conditions and the various reagents, solvents and catalysts used in the synthesis of aromatic amines are presented, along with the main advantages of the methodologies described.

This work describes the synthesis of new 1,3-benzoxathiol-2-one sulfonamides and evaluation of their ability to inhibit some in vitro (coagulant, proteolytic and hemolytic) and in vivo (hemorrhagic, edematogenic and lethality) toxic activities of Bothrops jararaca and Bothrops jararacussu venoms. Compounds have been synthesized from the coupling of intermediate 5-amino-6 methoxybenzo[d][1,3]oxathiol-2-one 4 with benzenesulfonyl chlorides. Characterization of the products was achieved by nuclear magnetic resonance (NMR) and electrospray ionization mass spectra (ESI-MS) techniques. Biological assay results have shown that most of compounds inhibited the main toxic activities of the venom of the two snake species. Compound 5b (N-(6 methoxy-2 oxobenzo[d][1,3]oxathiol-5-yl)-4-nitrobenzenesulfonamide) was the most efficient in inhibiting hemolysis of B. jararaca, and coagulation and proteolysis induced by both venoms. For in vivo activities, all compounds inhibited the edema, from 35 to 72%, and most of them exhibited antihemorrhagic and antilethality activities. Thus, the results pointed to the biological potential of these compounds, being promising molecules to treat envenomation by these snakes as well as to aid the current antivenom serum therapy.

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.