Isolation and identification of adenosine and phlomuroside from the aerial parts of Oryza sativa L.

Fresh and chopped aerial parts of Oryza sativa were extracted in 80% aqueous mehthanol, and the concentrated extract was successively partitioned in n-hexane, ethyl acetate (EtOAc), n-butanol (n-BuOH), and H₂O fractions. From the n-BuOH fraction, two compounds were isolated through repeated silica gel and ODS column chromatography (c.c.). Based on nuclear magnetic resonance (NMR), mass spectrometry and infrared spectroscopy spectroscopic data, the compounds were identified to be adenosine (1) and phlomuroside (2). Especially, the configuration of both the anomer hydroxyl groups was determined as β from the coupling constants of the anomer protons (J =6.0 and 7.6 Hz) in the ¹H-NMR spectra. This is the first report for the isolation of these compounds from Oryza sativa L.