New Phloroglucinol Derivatives from the Fruit Tree Syzygium jambos and Their Cytotoxic and Antioxidant Activities.

Seven new phloroglucinol derivatives (1-7) were isolated from the fruit tree Syzygium jambos together with four known triterpenoids (8-11) and two known flavones (12 and 13). According to the spectroscopic analyses (infrared, electrospray ionization mass spectrometry (ESIMS), high-resolution ESIMS, 1D and 2D nuclear magnetic resonance), the structures of compounds 1-7 were elucidated as jambone A (1), jambone B (2), jambone C (3), jambone D (4), jambone E (5), jambone F (6), and jambone G (7). All the isolates were determined for their cytotoxic activities on melanoma cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and compounds 10 and 11 showed potent activities. Moreover, compounds 1, 2, 4-7, 12, and 13 exhibited weak antioxidant activities under ferric-reducing antioxidant power and 2,2-diphenyl-1-picryhydrazyl radical-scavenging assays.

A new diterpenoid from the aerial parts of Andrographis paniculata.

One new and seven known diterpenoids were isolated from the aerial parts of Andrographis paniculata, and their structures elucidated on the basis of spectroscopic and spectrometric analysis, as well as chemical methods. The in vitro antiviral activities of these compounds against respiratory syncytial virus (RSV) were assayed.