Chromone Derivatives from Whole Plants of Chamaecrista rotundifolia and their Antibacterial Activity

In our search for new bioactive metabolites from plants of Cassia genus, the phytochemical investigation on the whole plants of C. rotundifolia was carried out, and that led to the isolation of two new ( 1 and 2 ) and five known ( 3–7 ) chromones. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Interestingly, 1 and 2 showed good anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activities with IZD of 13.2 ± 2.4 and 15.8 ± 2.6 mm, respectively.