Studies in the biochemistry of micro-organisms

isolated from the mycelium of Helminthosporium gramineum Rabenhorst two hitherto undescribed hydroxyanthraquinones which they named helminthosporin (4:5:8-trihydroxy-2-methylanthraquinone) and hydroxy- isohelminthosporin, Cl5H1006. Since the latter substance was found by Raistrick et al. [1934] to be the main colouring matter of Helminthosporium catenarium Dreohsler its name was altered by these workers to catenarin. Catenarin was shown by them to contain four hydroxyl groups, to give 2- methylanthracene on zinc dust distillation and, for reasons for which the original work must be consulted, was believed to be a 1:5:8-trihydroxy(hydroxy- methyl)-anthraquinone with the hydroxymethyl group either in position 2, 6 or 7.