A new diacylated labdane diterpenoid from Andrographis wightiana

Area of Science:

• Natural Products Chemistry
• Phytochemistry
• Organic Chemistry

Background:

• Andrographis wightiana is a plant species known for its diverse chemical constituents.
• Diterpenoids and flavones are classes of natural products with significant biological activities.

Purpose of the Study:

• To isolate and characterize chemical compounds from the whole plant of Andrographis wightiana.
• To elucidate the structure of a newly discovered acylated labdane diterpenoid.

Main Methods:

• Phytochemical investigation involving extraction and isolation techniques.
• Structure elucidation using comprehensive 1D and 2D-Nuclear Magnetic Resonance (NMR) spectral analyses.
• Identification of known labdane diterpenoids and flavones.

Main Results:

• Isolation of a new acylated labdane diterpenoid, 14-deoxy-3,19-diacetyl-11,12-didehydroandrographolide (1).
• Identification of three known labdane diterpenoids: wightionolide (2), andrographolide (3), and neoandrographolide (4).
• Identification of three known flavones: echioidinin (5), skullcapflavone I 2'-methyl ether (6), and echioidin (7).

Conclusions:

• The chemical profile of Andrographis wightiana includes a novel diterpenoid and several known compounds.
• The structure of the new compound was confirmed through detailed spectroscopic analysis.
• This study expands the knowledge of Andrographis wightiana's secondary metabolites.