Water → 9-(2-Acetoxyethoxymethyl)guanine

Participants

Reaction Conditions

Reaction Steps

A mixture of 10 gms (66 mmoles) of guanine, 50 ml of hexamethyldisilazane, and 0.4 gms (3 mmmol) of ammonium sulfate was heated to 115°-118° C. for 18 hours. The ammonia gas was removed as it was formed. After 18 hours of heating, a solution was formed indicating the completion of silylation. To this solution was added 15 gms (85 mmol) of 2-oxa-1,4-butanediol diacetate and 0.1 ml of trimethylsilyl triftriflate. The mixture was heated to 130° C. for a period of 4.5 hours. The solution was cooled to 50° C. and 10 ml of water dissolved in 100 ml of acetone was added. The mixture was heated to reflux and a precipitate was formed immediately. The mixture was cooled and the solid was collected by filtration to yield 10.1 g (58% yield) of 9-(2-acetoxyethoxy)methylguanine, with a 13:1 ratio of N-9 to N-7 isomer. Characteristic analytical data are as follows: 1H NMR (DMSO-d6) δ1.90 (3H, singlet, --OAc) , 3.58 (2H, multiplet, --OCH2 --) , 4.0 (2H, multiplet, --CH2OAc) , 5.25 (2H, singlet, --NCH2O--), 6.5 (2H, br singlet, --NH2), 7.75 (1H, singlet, --N=CH--N--).

Provenance & Evidence