Investigation of Heck coupling on 6-bromo[2,3-d]thienopyrimidines for construction of new EGFR inhibitor lead structures
作者:F. Bysting、S. Bugge、E. Sundby、B. H. Hoff
DOI:10.1039/c7ra01961k
日期:——
With the aim of identifying new lead structures for EGFR inhibition, a study of palladium catalysed Heck coupling between (R)-6-bromo-N-(1-phenylethyl)thieno[2,3-d]pyrimidin-4-amine and various acrylates was performed.
Thieno[2,3-d]pyrimidines are attractive derivatives for cancer treatment, among others through regulation of the epidermal growth factor receptor tyrosine kinase (EGFR-TK). In an extended SAR study, 44 new compounds of this class have been evaluated as inhibitors, while simultaneously focussing on ADME properties. Through the application of bioisosters, hybrid structures, solubilizing tails, and a combination approach several successful alterations in terms of activity and physiochemical properties were accomplished. Compounds based on benzylamines were found superior to aniline hybrid structures with respect to activity and ADME profile. Exploration of the former class revealed meta- and para amides as favourable 6-aryl substituents, contributing to an increase in activity and acting as a linker for solubilizing tails. Next, combinations of activity-inducing groups on the same scaffold resulted in new drug candidates. Compounds containing 6-aryls with the (2-(dimethylamino)ethyl)carbamoyl substituent were found equipotent to Erlotinib. Compared to this commercial drug, improved solubility and metabolic stability were observed. However, the thieno[2,3-d]pyrimidines with a solubilizing tail was by Caco-2 experiments found to have permeability issues, making further drug development difficult. Selected compounds were further analysed for toxicity and teratogenicity in zebrafish embryos. Two thienopyrimidines were both found to be less lethal than Erlotinib and to perform as well in terms of teratogenicity. Finally, the most promising thienopyrimidine drug was evaluated in a panel of human cancer cell lines, showing a clear potential for thienopyrimidines as anti-cancer agents. (C) 2015 Elsevier Masson SAS. All rights reserved.
Route selection in the synthesis of C-4 and C-6 substituted thienopyrimidines
作者:Steffen Bugge、Svein Jacob Kaspersen、Eirik Sundby、Bård Helge Hoff
DOI:10.1016/j.tet.2012.08.090
日期:2012.11
possibilities of selective Suzuki reactions on 6-bromo-4-chlorothienopyrimidine were investigated. The preference for mono arylation at C-6 could be increased, in the case of Pd(PPh3)4 catalysis, by reducing the water content of the reaction, or by using less electron rich Pd-ligands. The highest selectivity was obtained with Pd(OAc)2 or Pd2(dba)3, while reactions with the more electron rich Pd(PPh3)4 and