成人免费xx,国产又黄又湿又刺激不卡网站,成人性视频app菠萝网站,色天天天天

Welcome to chemicalbook!
Chinese English Japanese Germany Korea
400-158-6606
Try our best to find the right business for you.
Do not miss inquiry messages Please log in to view all inquiry messages.

Welcome back!

ChemicalBook CAS DataBase List ALPHA-L-ERYTHRO-PENTOFURANOSYL CHLORIDE-2-DEOXY-BIS(4-METHYL BENZOATE)
141846-57-3

ALPHA-L-ERYTHRO-PENTOFURANOSYL CHLORIDE-2-DEOXY-BIS(4-METHYL BENZOATE) synthesis

5synthesis methods
-

Yield:141846-57-3 90%

Reaction Conditions:

with hydrogenchloride;acetyl chloride in toluene at 5 - 15; for 1 h;

Steps:

6

EXAMPLE 6 Synthesis of 1-chloro-3o5-di-O-toluoyl-2-deoxy-L-ribofuranoside [Compound of formula (I) in which R is 4-methyl-benzoyl] To the toluenic solution of 1-0-methyl-3, 5-di-O-toluoyl-2-deoxy-L-ribofuranoside, prepared as described above in Example 4,77 ml (1. 08 mol) of acetyl chloride are added. The solution is cooled down to 5°C and hydrochloric acid is bubbled into the solution, controlling the bubbling so as to maintain the inner temperature below 15°C. After the addition the solution is left under stirring at 5°C, after about 30 minutes the product precipitates as white solid. After 1 hour a TLC check is performed in order to evaluate absence of the spot corresponding to the starting product. With a positive analytical check the operation is proceeded forward, otherwise the suspension is left under stirring for a further hour. The apparatus is put under vacuum for 2 hours to remove gaseous hydrochloric acid in excess, then the solid is filtrated and washed with 100 mi of toluene and with 50 ml of hexane. The solid is exsiccated under vacuum at 35-40°C until constant weight. 140 g (0.36 moles) of 1-chloro-3, 5-di-O-toluoyl-2-deoxy-L-ribofuranoside are obtained. Yield = 90%. 1H-NMR (CDCI3, 300 MHz): 5 ppm 8-7.89 (4H, dd, aromatic); 7. 28-7. 22 (4H, dd, aromatic); 6.48 (1H, d, H-1); 5.57 (1H, ddd, H-3); 4. 87 (1H, ddd, H-4); 4.64 (2H, AB system, CH2-5) ; 2. 81 (2H, m, CH2-2). 13C-NMR (CDCI3, 300 MHz): 5 ppm 166.63 and 166.39 (2 C=O) ; 144.51-126. 91 (C aromatic); 95.56 (C-1); 84.93 (C-4) ; 73.77 (C-3); 63.72 (C-5); 44. 75 (C-2); 21. 95 and 21.91 (2 CH3).

References:

WO2005/44832,2005,A1 Location in patent:Page/Page column 9-10

ALPHA-L-ERYTHRO-PENTOFURANOSYL CHLORIDE-2-DEOXY-BIS(4-METHYL BENZOATE) Related Search: