在基于MS/MS的分子网络的指导下,对软珊瑚衍生的真菌杂色曲霉的次级代谢产物的进一步见解导致了七个已知的环七肽的分离,即,五倍子酰胺A-C(1-3)和五倍子A-D(4-7)和一种不寻常的含吡咯并吲哚啉的新环七肽,五吡咯酮A(8)。通过全面的光谱数据分析阐明了8的结构,它的绝对配置是由先进的Marfey\的方法确定的。成功实现了1到8的半合成转化,并优化了反应条件。此外,半合成了一系列新的asperversiamideA(1)衍生物(10-19),并评估了它们对结核分枝杆菌H37Ra的抗结核活性。初步的结构-活性关系表明,丝氨酸羟基和色氨酸残基对活性很重要。
UNASSIGNED:在线版本包含补充材料,可在10.1007/s42995-022-00157-8获得。
Further insights on the secondary metabolites of a soft coral-derived fungus Aspergillus versicolor under the guidance of MS/MS-based molecular networking led to the isolation of seven known
cycloheptapeptides, namely, asperversiamides A-C (1-3) and asperheptatides A-D (4-7) and an unusual pyrroloindoline-containing new cycloheptapeptide, asperpyrroindotide A (8). The structure of 8 was elucidated by comprehensive spectroscopic data analysis, and its absolute configuration was determined by advanced Marfey\'s method. The semisynthetic transformation of 1 into 8 was successfully achieved and the reaction conditions were optimized. Additionally, a series of new derivatives (10-19) of asperversiamide A (1) was semi-synthesized and their anti-tubercular activities were evaluated against Mycobacterium tuberculosis H37Ra. The preliminary structure-activity relationships revealed that the serine hydroxy groups and the tryptophan residue are important to the activity.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s42995-022-00157-8.