Four new C16 1,2-dioxene-polyketides from the sponge Plakortis aff. simplex

Area of Science:

• Marine Natural Products Chemistry
• Organic Chemistry
• Biomedical Research

Background:

• Marine sponges are a rich source of structurally diverse natural products.
• Cyclic peroxides represent a class of compounds with significant biological activities.
• The genus Plakortis is known to produce various polyketide metabolites.

Purpose of the Study:

• To isolate and characterize novel cyclic peroxide-containing polyketide acids and their methyl esters from the marine sponge Plakortis aff. simplex.
• To investigate the structural features, particularly the number of 1,2-dioxene rings, in the isolated compounds.
• To evaluate the cytotoxic activity of the isolated methyl esters against P-388 murine leukemia cells.

Main Methods:

• Isolation of compounds using chromatographic techniques.
• Structure elucidation primarily through 1D and 2D Nuclear Magnetic Resonance (NMR) spectral analysis.
• Cytotoxicity assays using cultured P-388 murine leukemia cells.

Main Results:

• Two new cyclic peroxide-containing polyketide C16 acids (2 and 4) and their methyl esters (3 and 5) were successfully isolated.
• Compounds 2 and 3 possess a single 1,2-dioxene ring, while compounds 4 and 5 contain two 1,2-dioxene rings.
• Methyl esters 3 and 5 exhibited cytotoxic activity against P-388 murine leukemia cells.

Conclusions:

• The study successfully identified and characterized novel cyclic peroxide polyketides from Plakortis aff. simplex.
• The structural diversity, including the presence of one or two 1,2-dioxene rings, was confirmed.
• The cytotoxic potential of methyl esters 3 and 5 suggests their utility as lead compounds for further anticancer drug development.