Microbial-derived natural products provide unique bioactivities and serve as a unique source of drug leads. In the present study, we isolated one new chresdihydrochalcone (1), one new chresphenylacetone (2), and one known streptimidone (3) from Streptomyces chrestomyceticus BCC 24770 using antibacterial activity-guided isolation and purification procedures. We determined their molecular weights using MS and HRMS and elucidated their chemical structures from their 1D and 2D NMR and electronic circular dichroism (ECD) spectra. Compound 1 showed moderate inhibitory activities against the Gram-positive bacteria Methicillin-resistant Staphylococcus aureus, Bacillus subtilis, and Micrococcus luteus. Cytotoxicity and hemolytic activity were not observed at a concentration of up to 100 μg ml⁻¹. The specific antimicrobial activity and low toxicity of compound 1 indicate this compound to be a potential antibiotic candidate, especially as antibiotic resistance has become a significant public health threat.

微生物衍生的天然产物提供独特的生物活性，并作为独特的药物线索来源。在本研究中，我们使用抗菌活性指导的分离和纯化方法从链霉菌BCC 24770中分离出一种新的chresdihydrochalcone（1），一种新的chresphenylacetone（2）和一种已知的streptimidone（3）。我们使用MS和HRMS测定了它们的分子量，并通过1D和2D NMR和电子圆二色性（ECD）光谱阐明了它们的化学结构。化合物1显示出对革兰氏阳性细菌的耐甲氧西林金黄色葡萄球菌，枯草芽孢杆菌的中等抑制活性，和黄球菌。在高达100μgml ^-1的浓度下未观察到细胞毒性和溶血活性。化合物1的特定抗微生物活性和低毒性表明该化合物是潜在的候选抗生素，特别是因为抗生素耐药性已成为重大的公共卫生威胁。