تفاعل #6520

معادلة التفاعل

17

(2R,5S)-1-[2-(Butyldiphenylsiloxymethyl)-1,3-oxathiolan-5-yl]cytosine

tetrabutylammonium fluoride

→

3

المردود 75.0%

(2R,5S)-1-[2-(Hydroxymethyl)-1,3-oxathiolan-5-yl]cytosine

المردود 75.0%

المذيبات

THF

THF

ظروف التفاعل

المعالجة

1. 1
   أخرىthe disappearance of starting material (30 min)
2. 2
   تركيزThe reaction mixture was concentrated under reduced pressure
3. 3
   أخرىthe residue purified by preparative TLC

الإجراء التجريبي

To a solution of the β anomer 17 (0.15 g, 0.32 mmol) in THF (25 mL) was added tetrabutylammonium fluoride 1M in THF (0.35 mL, 0.35 mmol, 1.1 eq) and the reaction was allowed to stir at room temperature until TLC indicated the disappearance of starting material (30 min). The reaction mixture was concentrated under reduced pressure and the residue purified by preparative TLC using 12% MeOH/CHCl3 as development solvent to give 0.055 g (75%) of 3 from ethyl ether/MeOH (trace) as a white crystalline solid. [α]23D =-121.6 (c 1.1, MeOH) (for the S,R isomer 2 [α]23D =120.96 (c 1.06, MeOH)); 1H NMR: ((CD3)2SO) δ 3.03 (dd, J5,4a =4.4 Hz, J4a,4b =11.86 Hz, 1 H, 4a-H), 3.43 (dd, J5,4b =5.3 Hz, J4a,4b =11.86 Hz, 1 H, 4b-H), 3.80 (app t on D2O exchange goes to d, J2,2-CH2-OR =4.17 Hz, 2 H, 2-CH2 -OH), 5.27 (t, J2-CH2,OH =4.6 Hz, 1 H, 2-CH2OH), 5.22 (t, J2,2-CH2-OH =4.17 Hz, 1 H, 2-H), 5.88 (d, J5,6 =7.47 Hz, 1 H, H-5), 6.21 (app t, J=5.05 and 4.84 Hz, 1 H, 5-H), 7.19 (bs, 2 H, NH2), 7.89 (d, J5,6 =7.47 Hz, 1 H, H-6).

المصدر