Total synthesis of the anticancer natural product OSW-1.
The highly potent anticancer natural saponin OSW-1 has been successfully synthesized from commercially available 5-androsten-3beta-ol-17-one 79 in 10 operations with 28% overall yield. The key steps in the total synthesis included a highly regio- and stereoselective selenium dioxide-mediated allylic oxidation of 80 and a highly stereoselective 1,4-addition of alpha-alkoxy vinyl cuprates 68 to steroid 17(20)-en-16-one 12E to introduce the steroid side chain. This total synthesis demonstrated once again the versatile synthetic applications of alpha-halo vinyl ether chemistry developed in our laboratories.
Yu
Wensheng
W
Division of Medicinal and Natural Products Chemistry, College of Pharmacy, The University of Iowa, Iowa City, Iowa 52242, USA.
Jin
Zhendong
Z
D000972:Antineoplastic Agents, Phytogenic / Q000138:chemical synthesis*; D002783:Cholestenones; D003687:Dehydroepiandrosterone / Q000737:chemistry; D019668:Liliaceae / Q000737:chemistry; D012503:Saponins / Q000138:chemical synthesis*; D013237:Stereoisomerism
D000972:Antineoplastic Agents, Phytogenic; D002783:Cholestenones; D012503:Saponins; C106408:OSW 1; D003687:Dehydroepiandrosterone