AUTHOR=Lin Xiao , Zhou Yongjun , Liu Liyun , Zhu Hongrui , Chen Yeping , Wang Shuping , Sun Fan , Chai Ling , Liu Buming , Xu Shihai , Lin Hou-Wen 

TITLE=Compound Discovery and Structure-Activity Relationship Study of Neoantimycins Against Drug-Resistant Cancer Cells

JOURNAL=Frontiers in Chemistry

VOLUME=7

YEAR=2019

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2019.00481

DOI=10.3389/fchem.2019.00481

ISSN=2296-2646

ABSTRACT=<p>Four neoantimycins H-K (1–4) with C1-keto, including the new ones (1–2), were isolated from the culture of <italic>Streptomyces conglobatus</italic> RJ8. After enzymatically converting into their respective reduced type derivatives (5–8) <italic>in vitro</italic>, the absolute structures of 1–8 were established/reconfirmed by analyzing hydrolyzed components. The obtained NATs (4, 7, and 8) exhibited excellent cytotoxicity against drug-resistant colon and gastric cancer cells but low toxicity in the noncancerous cell. Further SAR investigation suggested that C1-hydroxyl, C9-isobutyl, and <italic>N</italic>-formyl contribute to the antiproliferation remarkably.</p>