Development of Mithramycin Analogues with Increased Selectivity toward ETS Transcription Factor Expressing Cancers
摘要:
Mithramycin A (1) was identified as the top potential inhibitor of the aberrant ETS transcription factor EWSFLI1, which causes Ewing sarcoma. Unfortunately, 1 has a narrow therapeutic window, compelling us to seek less toxic and more selective analogues. Here, we used MTMSA (2) to generate analogues via peptide coupling and fragment-based drug development strategies. Cytotoxicity assays in ETS and non-ETS dependent cell lines identified two dipeptide analogues, 60 and 61, with 19.1- and 15.6-fold selectivity, respectively, compared to 1.5-fold for 1. Importantly, the cytotoxicity of 60 and 61 is <100 nM in ETS cells. Molecular assays demonstrated the inhibitory capacity of these analogues against EWS-FLI1 mediated transcription in Ewing sarcoma. Structural analysis shows that positioning the tryptophan residue in a distal position improves selectivity, presumably via interaction with the ETS transcription factor. Thus, these analogues may present new ways to target transcription factors for clinical use.
Palladium-Catalyzed, Modular Synthesis of Highly Functionalized Indoles and Tryptophans by Direct Annulation of Substituted <i>o</i>-Haloanilines and Aldehydes
作者:Yanxing Jia、Jieping Zhu
DOI:10.1021/jo061471s
日期:2006.9.1
One-pot synthesis of indoles by a palladium-catalyzed annulation of ortho-haloanilines and aldehydes has been developed. Coupling of ortho-iodoaniline with aldehyde is realized under mild ligandless conditions [Pd(OAc)2, DABCO, DMF, 85 °C], whereas X-Phos is found to be the ligand of choice for coupling reactions involving ortho-chloroanilines/ortho-bromoanilines and aldehydes. A variety of ortho-haloanilines