Synonyms: Cytovaricin;Spiro[21,25-methano-2H,19H,23H-pyrano[2,3-h][1,5]dioxacyclotetracosin-23,2'-[2H]pyran],cytovaricin deriv.; NSC 349622;[3S-[3R*,4aR*,5E,5'R*,6'R*(S*),10S*,11S*,12R*,13S*,14S*,15R*,16S*,17E,21R*,23S*,25R*,26aR*,27S*]]-12-[(2,6-Dideoxy-3-O-methyl-b-D-ribo-hexopyranosyl)oxy]-3,3',4,4',4a,5',6',7,8,9,10,11,12,13,14,15,16,21,22,25,26,26a-docosahydro-10,11,13,15,16,26a-hexahydroxy-6'-(2-hydroxybutyl)-3,5',10,14,16,27-hexamethylspiro[21,25-methano-2H,19H,23H-pyrano[2,3-h][1,5]dioxacyclotetracosin-23,2'-[2H]pyran]-19-one