Synthesis of the N-acetylcysteamine thioester of seco-proansamitocin.
[structure: see text] The enantioselective total synthesis of the N-acetylcysteamine thioester of seco-proansamitocin, a key biosynthetic intermediate of the highly potent antitumor agent ansamitocin, is described, which twice utilizes the Nagao acetate aldol reaction, as well as an indium-mediated alkynylation of a benzyl bromide followed by carboalumination. The key step is a Heck reaction between two terminal alkenes for merging the two major fragments.
Frenzel
Thomas
T
Institut für Organische Chemie der Universität Hannover, Germany.
Brünjes
Marco
M
Quitschalle
Monika
M
Kirschning
Andreas
A
D003543:Cysteamine / Q000031:analogs & derivatives* / Q000737:chemistry; D004952:Esters; D008453:Maytansine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry
D004952:Esters; C507695:seco-proansamitocin; C023704:2-acetamidoethanethiol; D008453:Maytansine; D003543:Cysteamine