Two New Benzofulvene Sesquiterpenoids from the Stems of Nicotiana tabacum and their Antibacterial Activity

Two new benzofulvene sesquiterpenoids, tabanoids A and B (1 and 2) as well as five known sesquiterpenoids (3–7) were isolated from the stem of Nicotiana tabacum. Their structures were determined mainly by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1 and 2 were tested for their anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity. The results revealed that compounds 1 and 2 showed good inhibition with IZD of 15.2 ± 2.5, and 12.8 ± 2.2 mm, respectively.