Functional rearrangement of 3-Cl or 3,3-diCl-γ-lactams bearing a secondary 1-chloroalkyl substituent at C-4
作者:Mariella Pattarozzi、Fabrizio Roncaglia、Luca Accorsi、Andrew F. Parsons、Franco Ghelfi
DOI:10.1016/j.tet.2009.11.111
日期:2010.2
The study of the reaction with MeONa/MeOH of chlorinated gamma-lactams. prepared from the atom transfer radical cyclization of N-allyl-alpha-perchloroamides, has been extended to the case of substiates carrying an exo halogen atom on a branched carbon Only with secondary exo C-Cl groups, that are not located on a fused ring, does the functional rearrangement follow the typical transformation route, Which With trichloro-lactams can proceed further to give 4-alkylidene derivatives From a practical point of view, the outcome of the reaction with di- or trichloio N-cinnamylamides is synthetically valuable, affording the 5-methoxy-IH-pyrrol-2(5H)-one or 3-benzylidenepyrrlidine-2.5-dione. respectively. in good to excellent yield (C) 2009 Elsevier Ltd All rights reserved
Exocyclic Olefinic Maleimides: Synthesis and Application for Stable and Thiol-Selective Bioconjugation
作者:Dimpy Kalia、Pushpa V. Malekar、Manikandan Parthasarathy
DOI:10.1002/anie.201508118
日期:2016.1.22
reactions between biological thiols and endocyclic olefinicmaleimides are extensively used for site‐specific bioconjugation. The resulting thio‐succinimidyl linkages, however, lack stability because of their susceptibility to thiol exchange. Reported herein is that in contrast to their endocyclic counterparts, exocyclicolefinicmaleimides form highly stable thio‐Michael adducts which resist thiol exchange