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238 PROCEEDINGS OF INTERNATIONAL SCIENTIFIC CONFERENCE ON APPLIED BIOTECHNOLOGYsignals from the sugar moiety with chemical shifts %u03b4H ranging from 3.40 to 3.90, suggesting that compound 3 is a flavonoid glycoside. Correspondingly, the 13C-NMR spectrum of compound 3 shows signals for 15 carbons belonging to the flavonoid framework and 12 carbon signals from the sugar portion. A comparison of the 1Hand 13C-NMR spectral data of compound 3 with literature data [10] shows complete agreement. Therefore, compound 3 was identified as quercetin-3-O-rutinoside (rutin). Rutin has been shown to possess antioxidant activity, inhibit platelet aggregation, protect cells, exhibit anti-cancer effects, prevent blood coagulation and provide cardiovascular and vascular protection [11].Compound 4 was obtained as a colorless, amorphous solid. The 13C-NMR spectrum of compound 4 shows signals for 19 carbon atoms, including 4 methyl groups at the following chemical shifts dC (ppm): 24.67 (C-12); 23.42 (C-11); 21.19 (C10); 19.57 (C-13) and 1 carbonyl group at 201.36 ppm (C-3). The presence of 4 carbon atoms at these chemical shifts dC (ppm): 167.34 (C-5); 135.26 (C-7); 131.55 (C-8) and 127.18 (C-4) suggests the presence of 2 double bonds in the molecule. Additionally, the 13C-NMR spectrum of compound 4 also shows the presence of a sugar moiety with anomeric carbon at dC 102.72 ppm, indicating that the sugar is attached to the aglycone via an oxygen atom. Correspondingly, the 1H-NMR spectrum of compound 4 also reveals signals for 4 methyl groups at dH 1.05-1.94 ppm; 3 protons from the 2 double bonds at dH 5.87, 5.88 and 5.89 ppm; signals from 6 protons in the sugar moiety ranging from 3.20 to 3.87 ppm and the anomeric proton at dH 4.36 ppm. The coupling constant of the anomeric proton, J = 7.5 Hz, confirms that the sugar is attached to the aglycone through a %u03b2-D-glycoside bond. Furthermore, the structure of compound 4 is also supported by data from twodimensional HSQC and HMBC spectra. The direct connections between C and H are determined based on signals obtained