InCl3 mediated heteroarylation of indoles and their derivatization via C H activation strategy: Discovery of 2-(1H-indol-3-yl)-quinoxaline derivatives as a new class of PDE4B selective inhibitors for arthritis and/or multiple sclerosis
作者:Rajnikanth Sunke、Ramudu Bankala、B. Thirupataiah、E.V.V. Shivaji Ramarao、Jetta Sandeep Kumar、Hari Maduri Doss、Raghavender Medishetti、Pushkar Kulkarni、Ravi Kumar Kapavarapu、Mahaboobkhan Rasool、Jayesh Mudgal、Jessy E. Mathew、Gautham G. Shenoy、Kishore V.L. Parsa、Manojit Pal
DOI:10.1016/j.ejmech.2019.04.020
日期:2019.7
synthesized via the InCl3 mediated heteroarylation of indoles and their further derivatization through the Pd(II)-catalyzed CH activation strategy. This effort allowed us to discover a series of 2-(1H-indol-3-yl)-quinoxaline based inhibitors possessing PDE4B selectivity over PDE4D and PDE4C. One of these compounds i.e. 3b (PDE4B IC50 = 0.39 ± 0.13 μM with ∼27 and > 250 fold selectivity for PDE4B over PDE4D and
TFA alone was found to be remarkably effective for the intramolecular hydroarylation (IMHA) of alkynes when employed as a solvent in the cyclization of 3-alkynyl substituted2-(indol-3-yl)quinoxalines. This simple and metal free cyclization method afforded a range of indolophenazines as new and potential cytotoxic agents. The use of excess TFA was found to be crucial for the success of this reaction
the synthesis of mono and 2,3-disubstitutedquinoxalines by using a AlCl3 induced (hetero)arylation of 2,3-dichloroquinoxaline. Both symmetrical and unsymmetrical 2,3-disubstitutedquinoxalines can be prepared conveniently by using this method under appropriate reaction conditions. The reaction proceeds via C–C bond formation and can be utilized for the preparation of a variety of quinoxaline derivatives