Chemical constituents with antibacterial activity from Euphorbia sororia.

A group of ceramide (1) was isolated from the aerial parts of Euphorbia sororia. On the basis of spectroscopic data, chemical methods and GC-MS analysis, the structure of 1 was characterised as (2S,3S,4R,8E)-2-(eicosanoyl approximately octacosanoyl amino)-1,3,4-octadecanetriol-8-ene. In addition, four known ellagic acid derivatives 3,3'-di-O-methylellagic acid (2), 3,3',4'-tri-O-methylellagic acid (3), 4-O-sulfooxy-3,3'-di-O-methylellagic acid (4) and 4-O-sulfooxy- 3,3',4'-tri-O-methylellagic acid (5) were isolated from the plant. Biological screening of all compounds revealed moderate antibacterial activity.