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C. Ch, CH(CH 3 ) 2 ), CH, CH(CH 3 ) 2 ), 27.2 (CH 3 , CH(CH 3 ) 2 ) CH(CH 3 ) 2 ) CH(CH 3 ) 2 ) CH(CH 3 ) 2 ) CH(CH 3 ) 2 )

2. Hz and H. Ar, CDCl 3 ) ? 7, NMR: (400 MHz, p.8386

. Ml, The reaction mixture was then dissolved in 30 mL of EtOAc and washed once with a 01N HCl solution (20 mL) After adjusting the pH to 5 with a 3N NaOH solution, the aqueous phase was extracted six times with EtOAc. Subsequent flash chromatography on silica gel (EtOAc

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3. Ar, 81 (s, 3H, O-CH 3

2. Hz and H. Ar, CDCl 3 ) ? 7, NMR: (400 MHz, p.22

. Hz, 23 (s, 3H, CH 3 ), 1.58-1.50 (m, 4H

F. Nmr, CDCl 3 ) ? -113, 376 MHz

H. Ar, CDCl 3 ) ? 7.65 (dd, 3 J(H,H) = 8.0 Hz, NMR: (400 MHz, pp.7-46

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2. , J. =. 4h, and H. Ar, CDCl 3 ) ? 7, NMR: (400 MHz, pp.4-78

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. Nucléoside-carbocyclique, Contribution of N-Heterocyclic Carbene-Containing Catalysts in the Nucleoside Chemistry