Hydroxyalkylation with Cyclic Sulfates: Synthesis of Carbazole Derived CB2 Ligands with Increased Polarity

作者:Lueg Corinna; Galla Fabian; Frehland Bastian; Schepmann Dirk; Daniliuc Constantin G; Deuther Conrad Winnie; Brust Peter; Wuensch Bernhard
来源:Archiv der Pharmazie, 2014, 347(1): 21-31.
DOI:10.1002/ardp.201300255

摘要

In order to increase the polarity of the potent CB2 ligand 1a, the homologous hydroxyalkyl carbazoles 2a-c were prepared and pharmacologically evaluated. An important step in the synthesis is the hydroxyalkylation of carbazole with cyclic sulfates providing the 2-hydroxyethyl and 3-hydroxypropyl derivatives 5a and 5b in a one-step reaction. The final propionamides 2a-c were prepared using the recently reported coupling reagent COMU (R). The X-ray crystal structure of 2c displays an almost coplanar arrangement of the 3-phenyl-1,2,4-oxadiazole biaryl system. The increased polarity of 2a is associated with an almost 100-fold reduced CB2 affinity. The 3-hydroxypropyl derivative 2b represents the best compromise between lipophilicity and CB2 affinity (K-i=33nM).

  • 出版日期2014-1