Design, Synthesis, and Biological Activity of Thioguanine-Modified Pleuromutilin Derivatives.

Antibiotic overuse has caused the increasingly serious problem of bacterial drug resistance, with numerous marketed antibiotics exhibiting significantly reduced activity against drug-resistant bacteria. Therefore, there is urgent demand for the development of novel antibiotics. Pleuromutilin is a tricyclic diterpene exhibiting antibacterial activity against Gram-positive bacteria and is currently considered the most promising natural antibiotic. In this study, novel pleuromutilin derivatives were designed and synthesized by introducing thioguanine units, and their antibacterial activities against drug-resistant strains were evaluated in vitro and in vivo. Compound 6j was observed to have a rapid bactericidal effect, low cytotoxicity, and potent antibacterial activity. The in vitro results suggest that 6j has a significant therapeutic effect on local infections, and its activity is equal to that of retapamulin, an anti-Staphylococcus aureus pleuromutilin derivative.

Analysing the phenotype development of soybean plants using low-cost 3D reconstruction.

With the development of digital agriculture, 3D reconstruction technology has been widely used to analyse crop phenotypes. To date, most research on 3D reconstruction of field crops has been limited to analysis of population characteristics. Therefore, in this study, we propose a method based on low-cost 3D reconstruction technology to analyse the phenotype development during the whole growth period. Based on the phenotypic parameters extracted from the 3D reconstruction model, we identified the "phenotypic fingerprint" of the relevant phenotypes throughout the whole growth period of soybean plants and completed analysis of the plant growth patterns using a logistic growth model. The phenotypic fingerprint showed that, before the R3 period, the growth of the five varieties was similar. After the R5 period, the differences among the five cultivars gradually increased. This result indicates that the phenotypic fingerprint can accurately reveal the patterns of phenotypic changes. The logistic growth model of soybean plants revealed the time points of maximum growth rate of the five soybean varieties, and this information can provide a basis for developing guidelines for water and fertiliser application to crops. These findings will provide effective guidance for breeding and field management of soybean and other crops.