Synthesis and antimicrobial activities of novel galactoside derivatives containing a pyrimidine moiety

To find nitrogen heterocyclic derivatives with higher antimicrobial activities, thirteen novel galactoside derivatives containing a pyrimidine moiety were synthesized, and their structures were confirmed by ¹H NMR, ¹³C NMR and HRMS. The result of biological activity indicated that the target compounds possessed good antifungal activities against Phytophthora infestans, Gibberella zeae, Thanatephorus cucumeris, Botryosphaeria dothidea and Phompsis sp.. Among them, compound 4m showed excellent antifungal activities against P. infestans , with the EC₅₀ value of 8.67 μg/mL, which were similar with that of dimethomorph (EC₅₀ value 8.34 μg/mL). Moreover, the target compounds exhibited certain antibacterial activities against Xanthomonas citri subsp. citri and Xanthomonas oryzae pv. oryzae.