Antineoplastic agents, 177. Isolation and structure of phyllanthostatin 6.

The isolation and structural elucidation of a new Phyllanthus glycoside, phyllanthostatin 6 [7], was summarized. Phyllanthostatin 6 [7] was isolated from the roots of Phyllanthus acuminatus (Euphorbiaceae) and was found to inhibit (ED50 = 0.35 micrograms/ml) growth of the murine P-388 lymphocytic leukemia cell line. Two other new constituents were shown to be didesacetylphyllanthostatin 3 [9] and descinnamoylphyllanthocindiol [10]. Structure determinations were achieved employing hrfabms and 2D-nmr spectroscopy. Application of an hplc separation technique to the Phyllanthus glycosides and development of a new isolation procedure for the major antineoplastic constituent, phyllanthoside [1], are also described.