Journal of Natural Products 2007-03-01

Antineoplastic agents. 550. Synthesis of 10b(s)-epipancratistatin from (+)-narciclasine.

George R Pettit, Noeleen Melody, Delbert L Herald, John C Knight, Jean-Charles Chapuis

Index: J. Nat. Prod. 70(3) , 417-22, (2007)

Full Text: HTML

Abstract

By means of a five-step reaction sequence, narciclasine (2a), isolated from Narcissus sp., was converted to 10b(S)-epipancratistatin (3a) in 5.7% overall yield. The key step entailed a radical-initiated 10b,1 C-O cleavage employing tributyltin hydride to yield a B/C cis ring juncture (3b). Biological evaluation of 10b(S)-epipancratistatin (3a) provided evidence that antineoplastic activity was reduced by a factor of 10 when the B/C trans juncture was replaced with a B/C cis ring juncture.