A LC-MS-guided screening led to the isolation of two new streptimidone derivatives (2 and 3) containing a glutarimide ring and two glutarimide ring-opened compounds (4 and 5) along with a known glutarimide-containing polyketide, streptimidone (1) from Streptomyces sp. W3002 strain. Their structures were elucidated by MS and NMR spectroscopic analyses and by comparison with data from the literature. Compound 2 is a non-hydroxylated analog at the C-5 position of streptimidone. The structure of 3 was determined as a streptimidone derivative possessing the α, β-unsaturated ketone moiety at positions C-5 and C-6. Compound 4 had similar chemical shifts and splitting patterns with 3, but the glutarimide ring is opened. Compound 5 closely resembles that of 4 with the only difference being the existence of an additional methoxy group instead of an amide group. Streptimidone (1) and 3 showed weak cytotoxic activity against three human cancer cell lines, respectively.

中文翻译：

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从链霉菌属中分离出新的链霉二酮衍生物，戊二酰亚胺抗生素。W3002使用LC-MS指导的筛选。

LC-MS指导的筛选导致分离出两个新的链戊二酰亚胺酮衍生物（2和3），其中一个包含一个戊二酰亚胺环和两个戊二酰亚胺开环的化合物（4和5），以及一个已知的含戊二酰亚胺的聚酮化合物，链霉二酮（1）来自链霉菌属。W3002株。通过MS和NMR光谱分析并与文献数据比较，阐明了它们的结构。化合物2是在链霉酮的C-5位上的非羟基化类似物。确定3的结构为在位置C-5和C-6具有α，β-不饱和酮部分的链烷二酮衍生物。化合物4具有与3相似的化学位移和分裂模式，但是戊二酰亚胺环是打开的。化合物5与4的化合物非常相似，唯一的区别是存在另外的甲氧基而不是酰胺基。链霉酮（1）和3对三种人类癌细胞系分别显示出弱的细胞毒活性。