• Applied Biological Chemistry
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• v.39 no.3
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• pp.241-244
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• 1996

A bicyclic sesterterpene from Drechslera siccans was purified and structurally characterized. During the isolation procedure, the toxic component was monitored by the assay using Italian ryegrass (Lolium multiflorum Lam.), one of the host plants of the pathogen. Siccanol (1) named arbitrarily was shown to have a molecular formula of $C_{25}H_{38}_{4}$. Siccanol completely inhibited the root growth of the Italian regrass seedlings at a level of 100 ppm.

• Journal of Applied Biological Chemistry
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• v.61 no.1
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• pp.79-82
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• 2018

An ${\alpha}-{\text\tiny{D}}-glucoside$ of sesterterpene, 11-epiterpestacin, was isolated from the culture of a filamentous fungus Bipolaris sorokiniana NSDR-011. The structure was elucidated by chemical studies and spectroscopic methods including NMR and ESI-MS. 11-ETG (1) named arbitrarily did not inhibit the root growth of Italian ryegrass seedlings even at the level of 200 ppm, while its aglycone 11-ET (2) completely inhibited root growth at level of 100 ppm.

• Natural Product Sciences
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• v.21 no.4
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• pp.237-239
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• 2015

Sarcotragin C (1), a new sesterterpene metabolite was isolated from a Sarcotragus sp. sponge collected from Chuja Island, Korea. On the basis of the combined spectroscopic analyses, the structure of this compound was determined to be a linear norsesterterpene containing a leucine-derived ${\gamma}-lactam$ moiety. This compound exhibited moderate cytotoxicity against K562 and A549 cell-lines.

• Journal of the Korean Magnetic Resonance Society
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• v.25 no.2
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• pp.24-32
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• 2021

Two new sesterterpenes, including a known sesterterpene, were isolated from the marine sponge Haliclona sp. collected in the Gageo island, Korea. One of the new sesterterpenes (1) was an unusual compound possessing a spiroketal moiety and the other (2) represented a four ring-fused skeleton. The planar structure of compound 1 was identical to gombaspiroketals A and B isolated from the marine sponge Clathria gombawuiensis, but the configuration for the two chiral centers was different each other. On the other hand, the skeletal structure of compound 2 was similar to that of phorone A isolated from Phorbas sp. and a compound from C. gombawuiensis, except for one configuration at C-8. However, in comparing the ¹H and ¹³C NMR spectral data, the proton and carbon chemical shifts for the three compounds were almost consistent. The NOESY spectrum revealed that the C-8 configuration of 2 was reversed to that of the two reported compounds. The configuration for compound 2 was supported by quantum mechanical calculation for the carbon chemical shifts and DP4+ probability for the protons and carbons of 2.

• Journal of the Korean Magnetic Resonance Society
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• v.7 no.1
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• pp.55-61
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• 2003

Sarcotragins C(1) and D(2), two novel compounds, have been isolated from the sponge Sarcotragus sp. collected from Jaeju Island, Korea. The structures of these compounds have been determined to be linear sesterterpene alkaloids on the basis of combined 1D and 2D NMR experiments. The stereochemistry involved was established by comparison of the NMR data with those reported for a similar compound.

• Journal of the Korean Magnetic Resonance Society
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• v.16 no.1
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• pp.1-10
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• 2012

A new scalaran class sesterterpenoid with five known ones was isolated from a marine sponge Smenospongia species collected from the Gageo island, Korea. Chemical structure of all of compounds was determined on the basis of a combination of extensive 1D and 2D NMR experiments and MS data. The new compound exhibited a new functional group on a common scalaran sesterterpene skeleton, identified as 12-deacetoxy-23-deacetoxyscalarin. The compound 1 moderately showed the effect of the activation of AMP-activated protein kinase (AMPK) in L6 myoblast cell.

• Ocean and Polar Research
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• v.42 no.1
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• pp.15-20
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• 2020

The marine sponge Hyrtios sp. collected in the Philippines was extracted and partitioned. The resulting organic layer was purified by C₁₈ reversed-phase column chromatography and HPLC to achieve the separation of nine scalarane-type sesterterpenes, including one new compound with eight known scalarane analogs. The chemical structures of the isolated compounds 1-9 were elucidated by 1D and 2D NMR and MS data analysis. All nine compounds were evaluated for their antibacterial activities against three Gram-positive and three Gram-negative bacteria. The compound 3 exhibited potent antibacterial activities against Bacillus subtilis and Micrococcus luteus. The compounds 7 and 9 displayed considerable activities against Bacillus subtilis and the others had moderate results.