Juncins G and H: new briarane diterpenoids of the Indian Ocean gorgonian Junceella juncea Pallas

Study on the Chemical Constituents of the South China Sea Gorgonian Junceella juncea

“…During the course of our investigation on the chemical constituents of the South China Sea gorgonian coral J. juncea, a new steroidal glycoside-4Ј-O-acetyl-3-O-[b -D-arabino-pyranosyl-oxy]-cholest-5-ene-3b ,19-diol (1), and a new glycerol derivative-1,2-O-[2Ј-hydroxyoctadecyl]-glycerol (2), along with 16 known compounds were obtained. The 16 known compounds were identified as four sterols, namely, 24a-methylcholest-7,22-dien-3b,5a, 6b-triol (3), 3) 24a-methylcholest-3b,5a,6b-triol-25-monoacetate (4), 3) 24a-methylcholest-3b,5a,6b-triol (5), 3) 24a-methylcholest-5,23-dien-3b-ol (6), 6) five briarane diterpenes, namely, praelolide (7), 7) junceellin A (8), 7) gemmacolide A (9), 8) gemmacolide B (10), 8) junceellolide D (11), 9) six amine derivatives, namely, 1-O-b-D-glucopyranosyl-(2S,3S,4R,8Z)-2-N-(2Ј-hydroxypalmitoyl) octadecasphinga-8-ene (12), 10) (2S,3R)-2-N-palmitoyloctadecasphinga (13), 6) (2S,3R,4E)-2-N-palmitoyl-octadecasphinga-4-ene (14), 6) thymine (15), 6) uracil (16), 6) adenosine (17), 11) and batyl alcohol (18) 6) by NMR spectral analysis in comparison with authentic sample, respectively. It was the first time that steroidal glycoside was isolated from Junceella.…”

“…1) Among these 49 secondary metabolites, 15 briaranes, including juncins A-H, 2,3) (ϩ)-gemmacolides A-B, 3) juncenolides A-D, 4,5) junceellolide C, 5) and three steroids, namely, 24a-methylcholest-7,22-dien3b,5a,6b-triol, 3) 24a-methylcholest-3b,5a,6b,25-tetrol 3) and 24a-methylcholest-3b,5a,6b-triol-25-monoacetate 3) were obtained from J. juncea. During the course of our investigation on the chemical constituents of the South China Sea gorgonian coral J. juncea, a new steroidal glycoside-4Ј-O-acetyl-3-O-[b -D-arabino-pyranosyl-oxy]-cholest-5-ene-3b ,19-diol (1), and a new glycerol derivative-1,2-O-[2Ј-hydroxyoctadecyl]-glycerol (2), along with 16 known compounds were obtained.…”

Juncenolides F and G, Two New Briarane Diterpenoids from Taiwanese Gorgonian Junceella juncea

“…The IR spectrum displayed absorption bands diagnostic of hydroxyl, 5-membered lactone and ester groups. Both 1 H-and 13 C-NMR spectral data (Table 1 15,16) Besides the previous four ester carbonyls, the carbon signal at d 174.5 was assigned to a 5-membered lactone ring together with the oxygenated methine at d 81.2 (C-7). The two proton singlets at d 5.81 and 5.52 along with the CH 2 signal at d 121.2 were ascribed to an exocyclic methylene group.…”

“…In continuation of our interest in the chemistry and potential medicinal importance of briaranes, [12][13][14] we investigated the gorgonian octocoral Junceella juncea collected in Taiwan. Several juncins, 15,16) gemmacolides, 16) junceelolides 13) and juncenolides 12,14) have been reported from this species. The current study resulted in the isolation of the two novel briarane-type diterpenoidal compounds, juncenolides F (1) and G (2) from the acetone extract of Junceella juncea.…”

Ten New Antifouling Briarane Diterpenoids from the South China Sea Gorgonian Junceella juncea

“…4 Previous chemical investigations on J. juncea have yielded more than 20 briaranes. [5][6][7][8][9][10][11] During the course of our further investigation on the EtOH/CH 2 Cl 2 extract of J. juncea by semi-preparative HPLC, 10 new briarane diterpenoids, juncins R-ZI (1-10) were obtained from an EtOAc soluble fraction of the EtOH/CH 2 Cl 2 extract. Antifouling bioassay tests showed that the EtOAc soluble fraction led to 0% larval settlement and 10% mortality toward barnacle Balanus amphitrite (Cirripedia) larvae at concentration of 100.0 mg mL À1 , and compounds (1-10) all had potent antifouling activities against B. amphitrite larvae at nontoxic concentrations with EC 50 values of 0.004, 0.34, 2.65, 1.61, 3.77, 21.06, 0.004, 0.14, 1.47, and 0.51 mg mL À1 .…”