chemistry journal of moldova

I. Lunga et al./Chem.J.Mold. 2008, 3 (1), 89-93key correlation peaks between the proton signal at 4.39 (H-1 gal) and the carbon resonance at 79.1 (C-3 of theaglycon), the proton signal at 4.56 (H-1 glc) and the carbon resonance at 78.1 (C-2 gal), the proton signal at 4.69(H-1 glcI) and the carbon resonance at 82.5 (C-3 gal). Thus, the structure of compound 2 was deduced as 3--{[-Dglucopyranosyl-(12)]-[-D-glucopyranosyl-(13)]--D-galactopyranoside}-(25-R)-5-spirostan-3-ol, which wenamed hyoscyamoside C.1H NMR spectrum of compound 3 displayed signals for three tertiary methyl groups at 0.90 (3H, s, Me-19),0.91 (3H, s, Me-18) and 2.28 (3H, s, Me-21), one olefinic proton at 6.91 (1H, m, H-16) together with three anomericprotons (1H, d, 4.40; 1H, d, 4.56; 1H, d, 4.69). On the other hand, the 13 C-NMR signals due to a total of 21 carbonsignals originating from the sapogenol were composed of three methyl groups at 12.2, 15.7, and 26.8, one oxygenbearingmethine carbon at 79.1 (C-3), one carbonyl group at 199.3 (C-20), two quaternary carbons at 35.7 and47.2, four methine carbons at 34.7, 45.9, 56.1 and 57.3, eight methylene carbons at d 21.3, 29.5, 30.0, 32.8, 32.9,35.0, 35.7 and 37.9, and two olefinic carbons at d 147.0 and 156.4. The HMBC disclosed the connectivities of the abovefunctional carbons to form a pregnane skeleton. Using 1D-TOCSY, COSY, HSQC and HMBC spectra the sugar chainwere characterized as -D-galactose, two -D-glucose. HMBC spectrum showed key correlation picks between sugarsanomeric protons and attached carbons at 4.40 (H-1 gal) and 79.1 (C-3 agl), 4.56 (H-1 glc) and 80.2 (C-4 gal), 4.69 (H-1 glcI)and 84.7 (C-2 glc). Thus, compound 3 was elucidated as 3-O-D-glucopyranosyl (12)]- -D-glucopyranosyl-(14)--D-galactopyranosyl-5-pregn-16-en-20-one-3-ol, for which we proposed the name hyoscyamoside C 2.MeMeOOHMeMeMeOOHMeMeMeROHRO1: R=Glc(1-3)Gal 7: R=Rha(1-2)Glc2: R=[Glc(1-3)][Glc(1-2)]Gal4: R=Gal5: R=Glc(1-4)Gal6: R=Rha(1-2)Glc8: R=Glc(1-2)Glc(1-4)GalOR 1MeOMeMe19Me1221Me18Me142017OH16O232625HMe2719ROHRO3H573: R=Glc(1-2)Glc(1-4)Gal 9: R=Glc(1-4)GalR 1=Glc10: R=Glc(1-2)Glc(1-4)GalR 1=Glc90