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(+)- and (-)-Tedanine [(+)-1 and (-)-1], a pair of new enantiomeric indolone alkaloids, along with nine compounds (2–10) were isolated from the marine sponge Tedania sp. The structures of (+)-1 and (-)-1 including absolute configurations were determined by spectroscopic analysis and quantum chemical calculation. Compounds (+)-1 and (-)-1 were the first examples of indolone alkaloids isolated from this genus. In addition, the cytotoxic and antibacterial activities of these compounds were also evaluated. [ABSTRACT FROM AUTHOR]

Two new alkaloids, spongimides A (1) and B (2), along with five known ones (3–7), were isolated from the marine sponge Spongia sp. The structures of 1 and 2 were determined by the spectroscopic methods (UV, IR, MS, and NMR) and X-ray diffraction analysis. Compounds 1, 3, and 4 were the first examples of 2,4-imidazolidinediones isolated from this genus. In addition, the cytotoxic and antibacterial activities of compounds 1 and 2 were also evaluated. [ABSTRACT FROM AUTHOR]

Two new halogenated metabolites, laurenhalogens A (1) and B (2), along with four known ones (3–6), were isolated from the red alga Laurencia sp. The structures of 1 and 2 were determined by the means of UV, IR, MS, NMR and X-ray diffraction analysis. In addition, the antibacterial activities of 1–6 were also evaluated. [ABSTRACT FROM AUTHOR]

Five new stilbene glycosides (1–5), together with six known ones, were isolated from the roots of Polygonum multiflorum. Their structures were elucidated on the basis of spectroscopic analysis and chemical evidence. [ABSTRACT FROM AUTHOR]

Two new euglobals, R1 (1) and R2 (2), together with eight known euglobals (3–10) were isolated from the leaves of Eucalyptus robusta. Their structures were established by means of spectroscopic analysis and single-crystal X-ray diffraction. Euglobal R1 (1) represents a new skeleton of formyl-isovaleryl phloroglucinol-coupled β-phellandrene. [ABSTRACT FROM PUBLISHER]

Reaction of thianthrene cation radical tetrafluoroborate and hexafluorophosphate with an excess of 1,4-hexadiene, 1,5-hexadiene, 1,7-octadiene, 1,8-nonadiene and 1,9-decadiene gave, in each case, a mixture of bis- and monoadduct from addition to one of the diene’s double bonds. Addition to both double bonds did not occur. The monoadduct of each diene and the bisadduct (7a) of 1,5-hexadiene were isolated. All monoadducts and 7a were characterized with 1 H and 13 C NMR spectroscopy. By reaction on activated alumina adducts were converted into ( E )- and ( Z )-(5-thianthreniumyl)dienes, all of which were characterized with 1 H and 13 C NMR spectroscopy. The monoadduct (6a) of 1,4-hexadiene and the bisadduct 7a were characterized with X-ray crystallography. [ABSTRACT FROM AUTHOR]

Reaction of thianthrene cation radical tetrafluoroborate with 1,5-hexadiene, 1,7-octadiene, 1,8-nonadiene and 1,9-decadiene in the molar ratio 4:1 caused addition to occur to one and both of each diene’s double bonds. A mixture of four adducts was thus obtained, namely a bisadduct (12a–d), a monoadduct (13a–d), a di(bis)adduct (14a–d) and a di(mono)adduct (15a–d). The di(mono)adducts (15b–d) were isolated and characterized with 1 H and 13 C NMR spectroscopy. Under the same condition of excess of cation radical, addition occurred to only one double bond of 1,4-cyclohexadiene and 1,5-cyclooctadiene. Addition to both double bonds was not observed. The bisadduct (16) of 1,4-cyclohexadiene was characterized with 1 H and 13 C NMR spectroscopy and X-ray crystallography. On activated alumina, 15b–d underwent fast opening of dicationic rings to form mixtures of ( E , E ) – (17b–d) and ( E , Z )-di(5-thianthreniumyl)diene (18b–d) in which the ( E , E )-isomer was dominant and was characterized with 1 H and 13 C NMR spectroscopy. [ABSTRACT FROM AUTHOR]