Chemistry and Bioactivity of Briaranes from the South China Sea Gorgonian Dichotella gemmacea.

Seven new briarane diterpenoids, gemmacolides AZ-BF (-), were isolated together with eight known analogues (-) from the South China gorgonian . Their structures were elucidated based on detailed spectroscopic analysis and a comparison with reported data. In an in vitro bioassay, these compounds exhibited different levels of growth inhibition activity against A549 and MG63 cells, giving continuous evidences about the biological contribution of functional groups at C-2, C-12, C-13, and C-16.

Briarane diterpenoids from the gorgonian Dichotella gemmacea.

Seven new briarane diterpenoids, gemmacolides AS-AY (1-7), were isolated together with ten known analogues (8-17) from the South China Sea gorgonian Dichotella gemmacea. The structures of the new compounds were elucidated by the detailed analysis of spectroscopic data and comparison with reported data. The absolute configuration of compounds was determined based on electronic circular dichroism (ECD) experiments and genetic correlations as well.

Chemistry and tumor cell growth inhibitory activity of 11,20-epoxy-3Z,5(6)E-diene briaranes from the South China Sea gorgonian Dichotella gemmacea.

Eighteen new 11,20-epoxy-3Z,5E-dien briaranes, gemmacolides AA-AR (1-18), were isolated together with three known analogs, dichotellides F (19) and I (20), and juncenolide C (21), from the South China Sea gorgonian Dichotella gemmacea. The structures of the compounds were elucidated by detailed spectroscopic analysis and comparison with reported data. The absolute configuration was determined based on the ECD experiment.

New bioactive sulfated alkenes from the sea cucumber Apostichopus japonicus.

Two new alkene sulfates, (5Z)-dec-5-en-1-yl sulfate (4) and (3E)-dec-3-en-1-yl sulfate (5), together with three known sulfated alkanes, 2,6-dimethylheptyl sulfate (1), octyl sulfate (2), and decyl sulfate (3), were isolated from the sea cucumber Apostichopus japonicus. The structures of the new compounds 4 and 5 were elucidated by spectroscopic analysis, including ¹H-, ¹³C-, and 2D-NMR, ESI-MS, and HR-ESI-MS. Compounds 2 and 3 were isolated from natural sources for the first time.

Bioactive briarane diterpenoids from the South China Sea gorgonian Dichotella gemmacea.

Six new briarane diterpenoids, gemmacolides T-Y (1-6), were isolated together with three known analogs, juncenolide J (7), praelolide (8), and junceellolide C (9), from the South China Sea gorgonian Dichotella gemmacea. The structures of the new compounds were elucidated by detailed spectroscopic analysis and comparison with reported data. The absolute configuration was suggested based on biosynthetic considerations.

Bioactive (3Z,5E)-11,20-epoxybriara-3,5-dien-7,18-olide diterpenoids from the South China Sea gorgonian Dichotella gemmacea.

Six new (3Z,5E)-11,20-epoxybriara-3,5-dien-7,18-olide diterpenoids, gemmacolides N-S (1-6), were isolated together with four known analogues, juncenolide D, and juncins R, S and U (7-10), from the South China Sea gorgonian Dichotella gemmacea. The structures of the new compounds were elucidated by the detailed analysis of spectroscopic data in combination with the comparison with reported data. The absolute configuration of 1 was determined by a TDDFT calculation of its solution ECD spectrum, affording the determination of absolute configuration of other analogues by simply comparing their ECD spectra with that of 1.

Bioactive 11,20-epoxy-3,5(16)-diene briarane diterpenoids from the South China Sea gorgonian Dichotella gemmacea.

Seven new briarane diterpenoids, gemmacolides G-M (1-7), were isolated together with two known analogues, juncin O and junceellolide C, from the South China Sea gorgonian Dichotella gemmacea. The structures of the new compounds were elucidated by detailed analysis of spectroscopic data and comparison with reported data. In an in vitro bioassay, these compounds exhibited different levels of growth inhibition activity against A549 and MG63 cells.

Antifungal active triterpene glycosides from sea cucumber Holothuria scabra.

To study the new antifungal active triterpene glycosides of sea cucumber Holothuria scabra. Triterpene glycosides from Holothuria scabra were separated and purified by silica gel chromatography, reversed-phase silica gel chromatography and RP-HPLC. Their structures were elucidated on the basis of spectral data and chemical evidence.