Rhodomyrtals A–D, four unusual phloroglucinol-sesquiterpene adducts from Rhodomyrtus psidioides

Four novel compounds, rhodomyrtals A-D (1-4), with two unprecendented carbon frameworks of phloroglucinol coupled eudesmane, together with the known compound eucalyptin A (5) have been isolated from the leaves of the Australian plant Rhodomyrtus psidioides. The structures of compounds 1-4 were elucidated by spectroscopic analysis and ECD calculations. Some of the compounds showed good antibacterial activity against selected Gram-positive strains.