PARTIAL ASYMMETRIC PUMMERER REACTION OF ARYL PROP-2-YNYL SULFOXIDE WITH ACETIC ANHYDRIDE
作者:Tatsuo Numata、Osamu Itoh、Shigeru Oae
DOI:10.1246/cl.1977.909
日期:1977.8.5
The Pummerer reaction of aryl prop-2-ynyl sulfoxides with aceticanhydride was found to be stereospecific. From the 18O-tracer studies, the asymmetric induction at α-carbon is considered to be caused by an intramolecular and somewhat synchronized 1,2-acetoxy migration within the ylide intermediate.
In the course of our continuing studies on the 2-(benzo[b] thiophene-3'-yl)-6,8,8-triethyldesmosdumotin B (TEDB-TB) series, we designed and synthesized nine amino-TEDB-TB derivatives to improve pharmaceutical properties, identify structure activity relationships, and discover novel antitubulin agents. Among all newly synthesized amino-TEDB-TBs, the 5'- and 6'-amino derivatives, 6 and 7, exhibited significant antiproliferative activity against five human tumor cell lines, including an MDR subline overexpressing P-gp. The IC50 values of 0.50-1.01 mu M were 3-6 times better than those of previously reported hydroxy-TEDB-TBs. Compounds 6 and 7 inhibited tubulin polymerization, induced both depolymerization of interphase microtubules and multiple spindle formations, and caused cell arrest at prometaphase. Among all compounds, compound 7 scored best pharmaceutically with LogP 2.11 and biologically with greater antiproliferative activity and induction of cell cycle arrest at prometaphase. (C) 2017 Published by Elsevier Ltd.