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6-[2-(7-Methyljuglonyl)]isoxylospyrin, a 7-methyljuglone tetramer, was isolated from Diospyros chamaethamnus, and its structure elucidated by spectroscopic methods.

The naphthoquinone dimers natalenone, 8′-hydroxydiospyrin and euclanone and the trimers galpinone and a compound with MW 562 were isolated from E. natalensis roots. Natalenone is a dehydrodimer of 7-methyl- juglone with the two moieties linked by two CC bonds to give a fused tetracyclic structure, one ring bearing a methylene bridge. Galpinone is a 7-methyljuglone linear trimer, the three units probably being linked C-8-C-6′and C-3′-C-3″. Euclanone is a new dimer of 7-methyljuglone and methylnaphthazarin, isomeric with 8′-hydroxydiospyrin.

Diospyrin, isodiospyrin, 8′-hydroxydiospyrin, racemic 8′-hydroxyisodiospyrin and two other naphthoquinones have been isolated from Euclea pseudebenus . Euelein is recognized to be identical to diospyrin.

8,8′-Dihydroxy-4,4′-dimethoxy-6,6′-dimethyl-2,2′-binaphthyl-1,1′-quinone, 7-methyljuglone, 8′-hydroxydiospyrin, and eucleolatin have been isolated from the root bark of E. lanceolata . Eucleolatin is the 3,6′or 3,7′- dimer of 2-methylnaphthazarin.

7-MethyljugIone, 8,8′-dihydroxy-4,4′-dimethoxy-6,6′-dimethyl-2,2′-binaphthyl-1,1′-quinone, 2-methylnaphthazarin, mamegakinone and euclein have been isolated from Euclea pseudebenus . Euclein is the 3,6′-dimer of 7-methyljuglone.