172015-79-1

171887-04-0

172015-79-1

The general procedure for the synthesis of ((1S,4R)-4-(2-amino-6-chloro-9H-purin-9-yl)cyclopent-2-en-1-yl)methanol hydrochloride from abacavir intermediate A4 was as follows: to the reactor was added N-[2-amino-4-chloro-6-[[(1R,4S)-4-(hydroxymethyl)-2-cyclopenten-1-yl]amino]-5-pyrimidinyl] Formamide (0.1762 mol) and trichloromethylsilicate (7 vol). The reaction mixture was cooled to 0-5 °C and hydrochloric acid (0.7 vol) was added slowly at 0-10 °C. After addition, the reaction was held at 0-5 °C for 60 min. Subsequently, the reaction mixture was brought to room temperature and stirring was continued for 16-18 hours. Upon completion of the reaction, the solid product was collected by filtration and purified by recrystallization in methanol. (Yield: 76%, HPLC purity: 98.69%).