Six new prenylated acylphloroglucinols with menthane moieties, hypascyrins A−E (1−5) and ent-hyphenrone J (6), together with four known analogues, were isolated from Hypericum ascyron roots. Detailed spectroscopic data analyses resulted in the assignment of their structures. The absolute configuration of 1 was deduced by experimental and calculated ECD data, while those of 2−6 were assigned by ECD data analyses as well as chemical conversions. Hypascyrins A (1), C (3), and E (5) and ent-hyphenrone J (6) exhibited antimicrobial activity against MRSA (MIC 50 values of 4.0, 8.0, 2.0, and 4.0 μM, respectively) and Bacillus subtilis (MIC values of 4.0, 4.0, 2.0, and 4.0 μM, respectively).

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Two new dibenzo-1,4-dioxane derivatives, hyperdioxanes A (1) and B (2), were isolated from the roots of a Hypericaceous plant, Hypericum ascyron. Hyperdioxane A (1) is a conjugate of dibenzo-1,4-dioxane and sesquiterpene with an unprecedented heptacyclic ring system. The structures of 1 and 2 were assigned by detailed spectroscopic analyses, including application of a modified Mosher's method. A possible biogenetic pathway of hyperdioxane A (1) from hyperdioxane B (2) and a sesquiterpene, eremophil-9,11(13)-dien-8β,12-olide (3), is presented.

Structurally unique C 28 terpenoids, perovsfolins A (1) and B (2), were isolated from the aerial parts of an Uzbek medicinal plant, Perovskia scrophulariifolia (Lamiaceae). Their chemical structures including an unprecedented 6/8/6/6/6 pentacyclic carbon skeleton with a C 6 −C 3 ester moiety were elucidated on the basis of spectroscopic analyses aided by density functional theory calculations as well as chemical evidence. Perovsfolin B (2) exhibited an anti-neuroinflammatory activity.

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