Disubstituted 1,8-dipyrazolcarbazole derivatives as a new type of c-myc G-quadruplex binding ligands
摘要:
A series of 1,8-dipyrazolcarbazole (DPC) derivatives (6a-6d, 7a-7d) designed as G-quadruplex ligands have been synthesized and characterized. The FRET-melting and SPR results showed that the DPC derivatives could well recognize G-quadruplex with strong discrimination against the duplex DNA. In addition, the DPC derivatives showed much stronger stabilization activities and binding affinities for c-myc G-quadruplex rather than telomeric G-quadruplex. Therefore, their interactions with c-myc G-quadruplex were further explored by means of CD spectroscopy, PCR-stop assay, and molecular modeling. In cellular studies, all compounds showed strong cytotoxicity against cancer cells, while weak cytotoxicity towards normal cells. RT-PCR assay showed that compound 7b could down-regulate c-myc gene expression in Ramos cell line, while had no effect on c-myc expression in CA46 cell line with NHE III1 element removed, indicating its effective binding with G-quadruplex on c-myc oncogene in vivo. (C) 2012 Elsevier Ltd. All rights reserved.
Preparation and Study of 1,8-Di(pyrid-2′-yl)carbazoles
作者:Maria S. Mudadu、Ajay N. Singh、Randolph P. Thummel
DOI:10.1021/jo801132w
日期:2008.9.1
series of three derivatives of 1,8-di(pyrid-2'-yl)carbazole were prepared by Stille-type coupling of 2-(tri-n-butylstannyl)pyridine with the appropriate 1,8-dibromocarbazole. The carbazoles were prepared by appropriate substitution methodologies on the parent carbazole or by palladium-catalyzed cyclization of di-(p-tolyl)amine to provide the carbazole ring system. An X-ray structure of the di-tert-butyl
The manuscript describes our studies on a newly designed tridentate ligand. The new ligand 1 was successfully synthesized, and it was found that the asymmetriccatalysis of Nozaki-Hiyama allylation with ligand 1 affords the product with good enantioselectivity in high yield.