Neo-clerodane diterpenoids from Conyza pyrrhopappa Sch.Bip. ex A.Rich

Abstract

Two hitherto unknown neo-clerodane-type diterpenoids along with twelve known compounds have been isolated from Conyza pyrrhopappa Sch.Bip. ex A.Rich, a medicinal plant traditionally used across tropical Africa to relieve fever. The structures of isolates have been elucidated by a combination of spectroscopic techniques. The crude extract and the isolated compounds were evaluated in the Hela-S3 cell line and in a panel of microorganisms (bacteria and fungi) at concentrations up to 50 µg/mL. The new compounds were inactive while the pentamethylated flavonoids showed low to significant activity against the cancer cell line used. However, none of the samples showed any activity against the tested microorganisms at this concentration. The present manuscript is the first investigation of the cytotoxicity of phytochemicals and extract from C. pyrrhopappa.

Keywords:

• Isolation
• Structure elucidation
• Neo-clerodanes
• Conyza pyrrhopappa
• Asteraceae
• Cytotoxicity
• Antimicrobial

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

GTBM is grateful to the German Academic Exchange Service (DAAD) (57381410) and the Institute for Organic Chemistry of the University Johannes Gutenberg of Mainz for financial support.

Notes on contributors

Gabin Thierry M. Bitchagno

GTMB was field investigator and drafted the manuscript. MK helped in isolation of compounds. AS performed biological evaluation. TO, IKS and PT revised the manuscript and supervised the work. All the authors read and approved the manuscript.

Anja Schüffler

GTMB was field investigator and drafted the manuscript. MK helped in isolation of compounds. AS performed biological evaluation. TO, IKS and PT revised the manuscript and supervised the work. All the authors read and approved the manuscript.

Ingrid K. Simo

GTMB was field investigator and drafted the manuscript. MK helped in isolation of compounds. AS performed biological evaluation. TO, IKS and PT revised the manuscript and supervised the work. All the authors read and approved the manuscript.

Matthias Krumb

GTMB was field investigator and drafted the manuscript. MK helped in isolation of compounds. AS performed biological evaluation. TO, IKS and PT revised the manuscript and supervised the work. All the authors read and approved the manuscript.

Pierre Tane

GTMB was field investigator and drafted the manuscript. MK helped in isolation of compounds. AS performed biological evaluation. TO, IKS and PT revised the manuscript and supervised the work. All the authors read and approved the manuscript.

Till Opatz

GTMB was field investigator and drafted the manuscript. MK helped in isolation of compounds. AS performed biological evaluation. TO, IKS and PT revised the manuscript and supervised the work. All the authors read and approved the manuscript.