In December 2019, the first case of severe acute respiratory syndrome (COVID-19), caused by the new coronavirus (SARS-CoV-2) was reported and the disease was declared as a worldwide pandemic in March 2020. As there is no vaccine currently available, the daily hygiene cleaning habits and social distance are the ways to fight COVID-19 indicated by the WHO. Hand and surface hygiene has become essential and the use of 60-90% ethanol is recommended for its effective biocide action. Phenol-based products are effective sanitizers, but they can cause irritation and are not recommended for surfaces that come into contact with food. There are quaternary ammonium salts that present low toxic and are good sanitizers, as they can cause the denaturation of proteins and disruption of viral lipid bilayer. Sodium hypochlorite is one of the most used sanitizers due to its low cost and effective oxidative capacity. In the same direction, peroxides are also used as a biocide, as they cause oxidation of lipids and denaturation of viral proteins. The goal of this paper is to describe the action modes and chemical concepts of the sanitizers recommended by the ANVISA-Brazil to be used against the new coronavirus.

Phloea subquadrata and Phloeophana longirostris are subsocial species that differ from each other in their host plants and degrees of aggregation. Until recently, only ten low-molecular weight compounds, a sesquiterpene, and dimers of (E)-4-oxo-2-hexenal had been reported from the contents of P. subquadrata glands. Here, the main goal was to distinguish the volatile compounds released by adult males, adult females and nymphs of the two species. The analyses revealed 103 compounds, of which 44 were exclusive to Phloeophana longirostris and 15 were exclusive to Phloea subquadrata. The data were analyzed by chemometric methods, which discriminated the phloeid species by developmental stage and sex. (E)-2-Hexenal, (E)-4-oxo-2-hexenal and (E)-2-octenal were found in both species. Adult individuals were characterized by the presence of methyl 2-methylbutanoate, (E)-2-hexenyl acetate and 2-hexenyl butanoate, and nymphs were characterized by 5-ethyl-2(3H)-furanone and (E)-2-octenal. There was chemical distinction between volatiles of adults and nymphs of the two species studied.

Bark bugs belonging to the family Phloeidae are known for their camouflage on tree trunks. The nymphs store in dorsal abdominal glands defensive secretions with a pungent odor mainly constituted of (E)-2-hexenal, (E)-2-octenal, and (E)-4-oxo-2-hexenal. The metathoracic glands of adults (male and female) store (E)-2-hexen-1-ol and (E)-2-hexenyl acetate, which are less irritating than their corresponding aldehydes. Additional compounds of m/z 224 were detected in the scent glands of these insects and were previously suggested to be dimers of the (E)-4-oxo-2-hexenal. Thus, the aim of this study was to elucidate the details of the chemical structure of the dimers found in the scent glands of Phloea subquadrata. These dimers were obtained by synthesis and were compared with the natural products, confirming the dimeric structures of the latter. These (E)-4-oxo-2-hexenal dimeric compounds are novel and have not been reported before.