446265-65-2Relevant academic research and scientific papers
Stereoselective synthesis of structurally simplified cephalostatin analogues by multiple heck reactions and their biological evaluation
Tietze, Lutz F.,Krahnert, Wolf-Ruediger
, p. 2116 - 2125 (2007/10/03)
The stereoselective synthesis of structurally simplified heptacyclic cephalostatin analogues 2, 3, 18-21, 31, 32 and 33 by multiple Heck reactions is described. The key step of the synthesis is a selective Heck reaction of hydrindene 7 with 12 and 25, respectively at the vinyl bromide moiety followed by the introduction of a second molecule of 7 and a twofold intramolecular Heck reaction. The obtained bissteroidal heptacyclic compounds 2 and 3, in which the central octahydrophenazine moiety of 1 is replaced by a benzene ring, contain an unusual cis-annulation of the two newly generated rings. The cytotoxicity of some of the derivatives was determined on human lung cancer cell line A 549 in HTFCA tests (Human tumor colony forming ability). They show a rather high activity with an ED50 in the micro molar range.
