Sinunanolobatone A, an Anti-inflammatory Diterpenoid with Bicyclo[13.1.0]pentadecane Carbon Scaffold, and Related Casbanes from the Sanya Soft Coral Sinularia nanolobata

Abstract

A novel diterpenoid, sinunanolobatone A (1), featuring an unprecedented bicyclo[13.1.0]pentadecane carbon framework, along with two new casbane diterpenoids (2 and 3), and five known related ones (4-8) were isolated from the Sanya soft coral Sinularia nanolobata. The structures of the new compounds were established by detailed spectroscopic analysis, X-ray diffraction analysis, chemical reactions, or quantum chemical computation method. A plausible biosynthetic pathway of 1 and its biogenetic relationship with co-occurring casbanes was proposed. In bioassay, the novel compound 1 showed significant inhibitory activity against lipopolysaccharide (LPS) induced inflammation in BV-2 microglial cells.

Structural and Biological Insights into the Hot‐Spot Marine Natural Products Reported from 2012 to 2021

“…It exhibits strong inhibitory activity against lipopolysaccharide‐induced inflammation in BV‐2 microglial cells. [ 153 ]…”

Sinuscalide A: An Antiviral Norcembranoid with an 8/8-Fused Carbon Scaffold from the South China Sea Soft Coral Sinularia scabra

“…Soft corals of the genus Sinularia − (phylum Cnidaria, class Anthozoa, subclass Octocorallia, order Alcyonacea, family Alcyoniidae) are one of the most widely distributed soft coral genera over the oceans. To date, it has yielded a wealth of diverse and complex structures, especially various types of terpenoids, which possess a broad range of biological properties, such as cytotoxic, anti-inflammatory, immunosuppression, and antimalarial activities. , Among all of the species of Sinularia , Sinularia scabra has been mainly chemically investigated by Sheu’s group and Guo’s group from the soft coral samples in the Taiwan and the South China Sea, of which they obtained sesquiterpenoids, norditerpenoids, and cembranoids. − …”

“…To date, it has yielded a wealth of diverse and complex structures, especially various types of terpenoids, which possess a broad range of biological properties, such as cytotoxic, anti-inflammatory, immunosuppression, and antimalarial activities. 13,14 Among all of the species of Sinularia, Sinularia scabra has been mainly chemically investigated by Sheu's group and Guo's group from the soft coral samples in the Taiwan and the South China Sea, of which they obtained sesquiterpenoids, norditerpenoids, and cembranoids. 15−19 In the context of our continuous interest in the isolation of bioactive metabolites from soft corals, 20−22 a sample of S. scabra (No.…”

“…13 C{1 H} NMR (150 MHz) Data (δ C ) for 1-4 and 8 in CDCl 3 and H-13/H-14/H-1 correlations. The HMBC spectrum gave H-1, H 2 -2, H-5/C-3, H-5, H-13, H 2 -14/C-4, and H-5, H 2 -9, H-11, H-12, H 3 -18/C-7 correlations (Figure…”

“…. 1 H and13 C{ 1 H} NMR spectroscopic data, Tables1 and 2; HRESIMS m/z 313.1433 [M + H] + (calcd for C 19 H 21 O 4 , 313.1440). H and 13 C{ 1 H} NMR spectroscopic data, Tables 1 and 2; HRESIMS m/z 313.1434 [M + H] + (calcd for C 19 H 21 O 4 , 313.1440).…”