(1′R,2S,10′E,14′E,16′E,21′R)-6-sec-Butyl-21′,24′-dihydroxy-5,11′,13′,22′-tetramethyl-2′-oxo-5,6-dihydrospiro[pyran-2,6′-[3,7,19]trioxatetracyclo[15.6.1.1~4,8~.0~20,24~]pentacosa[10,14,16,22]tetraen]-1 2′-yl (4ξ)-2,6-dideoxy-4-O-[(4ξ)-2,6-dideoxy-3-O-methyl-α-L-threo-hexopyranosyl]-3-O-methyl-α-L-threo-hexopyranoside