Two new chalcones from Clerodendrum phlomidis

Abstract

Two new chalcones, 3,2′,3′-trihydroxy-4′-methoxychalcone (1) and 3,2′-dihydroxy-4′,6′-dimethoxychalcone (2), were isolated from the seeds of Clerodendrum phlomidis together with three known flavonoids, 5-hydroxy-7-methoxyflavanone (3), 5-hydroxy-7-methoxyflavone (4), and kaempferol-3-O-α-l-rhamnopyranoside (5). The structures of the new compounds 1 and 2 have been established mainly on the basis of 1D and 2D NMR studies.

Keywords::

• Clerodendrum phlomidis
• Verbenaceae
• seeds
• chalcones

Acknowledgements

The authors thank Dr Arul Marie and Mr Dubost Lionel, Laboratoire de Chimie et Biochimie des Substances Naturelles, MNHN, Paris, France, for providing mass spectral data. The NMR spectrometers used were funded jointly by the Région Ile-de-France, the Muséum National d'Histoire Naturelle (Paris, France), and by CNRS (France). The authors (AR and DG) are grateful to University Grants Commission (UGC), New Delhi, for financial assistance under UGC-RFSMS (BSR) and UGC-MRP Programmes.