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Abstract: Four novel polyisoprenylated benzophenone derivatives, paucinones A–D (1–4), were isolated from the leaves of the plant Garcinia paucinervis. Paucinones A–C (1–3) contained an unexpected cyclohexane-spiro-tetrahydrofuran moiety. A 1-methylene-3,3-dimethylcyclohexane group never reported before was found in the structure of paucinone D (4). The structures of these compounds were elucidated with spectroscopic evidences. The relative stereochemistries of 1–4 were determined by NOESY correlations. These compounds showed significant cytotoxicities against HeLa cells. [Copyright &y& Elsevier]

Abstract: A new rotaxane with functional chromophores porphyrin and fluorene as stoppers has been synthesized. It displays dual fluorescent character. The macrocycle ring can shuttle between the fumaramide part and the succinimide part on the dumbbell. Heating and UV light irradiating on the rotaxane lead to the reversible E/Z conversion, driving the ring to shuttle between the two stations. The optical properties of porphyrin and fluorene stoppers of the thread do not change so much while the ring shuttles because the macrocycle does not interact with the two stoppers. However, the active group, propargyloxyl, is introduced onto the two sides of the ring so that the rotaxane has the potential to be functionalized by further decoration. [Copyright &y& Elsevier]

Abstract: A novel asymmetric ent-kauranoid dimer, lushanrubescensin J ( 1 ), was isolated from Isodon rubescens var. lushanensis. Its structure was elucidated by the spectroscopic evidences. The stereochemistry was confirmed by the single crystal X-ray diffraction of its tetraacetate. Compound ( 1 ) exhibited potent inhibitory activity against K562 cells with IC50 =0.93μg/mL. [Copyright &y& Elsevier]