Two new diterpenoid lactones isolated from Andrographis paniculata.

Area of Science:

• Natural Product Chemistry
• Organic Chemistry
• Phytochemistry

Background:

• Andrographis paniculata is a medicinal plant known for its bioactive compounds.
• Diterpenoid lactones are a significant class of natural products with diverse biological activities.
• Isolation and structural elucidation of novel compounds contribute to understanding plant chemical diversity.

Purpose of the Study:

• To isolate and characterize new diterpenoid lactones from Andrographis paniculata.
• To elucidate the chemical structures of the isolated compounds using spectroscopic methods.
• To determine the stereochemical configurations of the novel compounds.

Main Methods:

• Extraction and isolation of compounds from the aerial parts of Andrographis paniculata.
• Structure elucidation using Nuclear Magnetic Resonance (NMR) and Mass Spectrometry (MS).
• Configuration determination via Rotating Frame Overhauser Effect Spectroscopy (ROESY) and single crystal X-ray diffraction.

Main Results:

• Two new diterpenoid lactones, 3-deoxy-andrographoside (1) and 14-deoxy-15-methoxy-andrographolide (2), were successfully isolated.
• The structures of compounds 1 and 2 were unambiguously determined through a combination of NMR, MS, and chemical analyses.
• The absolute configurations of the novel compounds were established using ROESY data and X-ray crystallography.

Conclusions:

• The study successfully identified and characterized two novel diterpenoid lactones from Andrographis paniculata.
• The findings expand the known chemical constituents of Andrographis paniculata.
• This research provides a foundation for further investigation into the biological activities of these new compounds.