(2'''R,4''R,5''R,6R,2'E)-6-{2'-[5''-(2'''-tert-butyldimethylsilyloxy-4'''-iodobut-3'''-ynyl)-2'',2'',4''-trimethyl-[1'',3'']dioxolan-4''-yl]-vinyl}-5,6-dihydro-pyran-2-one