A new conetituent,“vilangin”(I) has been isolated from the dry ripe berries of Embeh ribes. From a study of ita reactions and degradation producta, vilangin has been SRsigned the structure, methylenebis (2, 5-dihydroxy4undecyl-3, 6-benzoquinone). This ha been confirmed by synthesis using embelm (XVII) and formaldehyde.