A series of icaritin derivatives bearing carboxylic acid or carboxylic ester groups are synthesized, and their in vitro cytotoxic activity against three cancer cell lines, MCF-7, MDA-MB-435s, and A549, are evaluated by MTT assay. Several derivatives including 2h, 2j, 5b and 5d show higher cytotoxic activity than the parent compound icaritin against these cancer cell lines. Compounds 5b and 5d are even more cytotoxic to MCF-7 cells than the clinic drug tamoxifen. Moreover, compound 5b is found to be non-toxic to normal cells (Vero) and both 5b and 5d exhibit good selectivity towards estrogen receptor positive MCF-7 breast cancer cells over estrogen receptor negative MDA-MB-435s breast cancer cells. The structure activity relationship analysis has revealed that mono-substitution at either C-3 or C-7 hydroxyl group of icaritin could improve the cytotoxicity of icaritin, and the C-3 hydroxyl group may be a preferable site for chemical modification. In addition, the length, the flexibility and the additional branching substituent group of the substitution chain(s) at both C-3 and C-7 hydroxyl groups can all affect the anticancer activity of these derivatives. (C) 2015 Elsevier Masson SAS. All rights reserved.
Semisynthetic Flavone-Derived Antimicrobials with Therapeutic Potential against Methicillin-Resistant<i>Staphylococcus aureus</i>(MRSA)
作者:Shuimu Lin、Jun-Jie Koh、Thet Tun Aung、Wan Ling Wendy Sin、Fanghui Lim、Lin Wang、Rajamani Lakshminarayanan、Lei Zhou、Donald T. H. Tan、Derong Cao、Roger W. Beuerman、Li Ren、Shouping Liu
DOI:10.1021/acs.jmedchem.7b00380
日期:2017.7.27
A new series of semisynthetic flavone-based small molecules mimicking antimicrobial peptides has been designed from natural icaritin to combat drug-resistant Gram-positive bacterial infections. Compound 6 containing two arginine residues exhibited excellent antibacterial activity against Gram-positive bacteria, including MRSA, and very low toxicity to mammalian cells, resulting in a high selectivity