New long-chain aliphatic compounds from Peperomia dindygulensis

Abstract

Three long-chain aliphatic compounds, including one new polyketide derivative, dindygulerione C (1), one new octaketide derivative, dindygulerione D (2) and one new acylresorcinol derivative dindyguleranone (3) were isolated from the whole plant of the Chinese anticancer folk medicine Peperomia dindygulensis Miq. (Piperaceae). Dindygulerione C is an unprecedented example of a N-containing polyketide. The chemical structures and configurations of 1–3 were elucidated as (−)-(4S)-2-[(Z)-1′-(6″,7″-dihydroxyphenethyl-amino)octadec-11′-enylidene]-4-hydroxycyclohexane-1,3-dione (1), (+)-2-heptadecyl-4-hydroxy-3,4,7,8-tetrahydro-2H-chromen-5(6H)-one (2) and 2-(1,3-dihydroxyphenyl)-octacosan-1′-one (3), respectively, by comparing with the literature data and extensive spectroscopic methods, including 2-D NMR and circular dichroism spectroscopic analysis. The cytotoxicity of 1–3 was evaluated against Hep3B and HepG2 liver cancer cell lines.

Keywords:

• Peperomia dindygulensis
• long-chain aliphatic compounds
• N-containing polyketide
• octaketide derivative
• acylresorcinol derivative
• cytotoxicity

Acknowledgements

The authors gratefully acknowledge the assistance of Ms Fuqin Guan and Dr Qizhi Wang from Institute of Botany, Jiangsu Province and Chinese Academy of Science, for providing cytotoxic evaluation facilities.