反应详情

温度

120 °C

9-(2-Acetoxyethoxy)methylguanine (2 gms, 7.5 mmol) was dissolved in 15 ml of acetic anhydride. The mixture was heated to 120° C. and 0.1 gms (0.8 mmol) of 4-dimethylaminopyridine (DMAP) added. The reaction mixture was kept at 120° C. for 3 hours, then the mixture was cooled to 40° C. and 10 ml of toluene added. Hexane (20 ml) was added slowly to effect crystallization of the product. The solid was collected by filtration and washed with hexane, yielding 1.82 gms of 9-(2-acetoxyethoxy)methyl-N2 -acetylguanine (79%) with a N-9/N-7 isomer ratio of >200:1. Characteristic analytical data are as follows: 1H NMR (DMSO-d6) δ1.85 (3H, singlet, --NHCOCH3), 2.08 (3H, singlet, --O2CCH3) , 3.6 (2H, multiplet, --OCH2 --) , 3.95 (2H, multiplet, --CH2O--), 5.4 (2H, singlet, --NCH2O--) , 8.06 (1H, singlet, --N=CH--N--).

1. temperaturethe mixture was cooled to 40° C.
2. customcrystallization of the product
3. filtrationThe solid was collected by filtration
4. washwashed with hexane