Racemic dimethyl 2-hydroxy-4-[5-methyl-2(1H),4(3H)-dioxopyrimidin-1-yl]- (7a and 8a) and dimethyl 4-(6-aminopurin-9-yl)-2-hydroxycyclopentane-1,1-dicarboxylates (7b and 8b) were prepared by addition of sodium salt of thymine and adenine, respectively, to dimethyl (Z)-(4-oxobut-2-en-1-yl)malonate (1). Reduction of the diesters with sodium borohydride in methanol in the presence of sulfuric acid gave corresponding racemic 2,2-bis(hydroxymethyl)-4-[5-methyl-2(1H),4(3H)-dioxopyrimidin-1-yl]- (14a and 15a), 4-(6-aminopurin- 9-yl)-2,2-bis(hydroxymethyl)cyclopentan-1-ol (14b and 15b), methyl (±)-cis-2-hydroxy- 1-hydroxymethyl-4-[5-methyl-2(1H),4(3H)-dioxopyrimidin-1-yl]- (13a), and methyl (±)-cis-4-(6-aminopurin-9-yl)-2-hydroxy-1-hydroxymethylcyclopentan-1-carboxylate (13b), respectively.
通过将胸腺嘧啶和腺嘌呤的钠盐分别加入二甲基(Z)-(4-氧代丁-2-烯-1-基)丙二酸二甲酯(1),制备了拉氏二甲基2-羟基-4-[5-甲基-2(1H),4(3H)-二氧代嘧啶-1-基]-(7a和8a)和二甲基4-(6-氨基嘌呤-9-基)-2-羟基环戊烷-1,1-二羧酸二甲酯(7b和8b)。在甲醇中加入硼氢化钠和硫酸,将二酯还原,得到相应的拉氏2,2-双(羟甲基)-4-[5-甲基-2(1H),4(3H)-二氧代嘧啶-1-基]-(14a和15a)、4-(6-氨基嘌呤-9-基)-2,2-双(羟甲基)环戊烷-1-醇(14b和15b)、甲基(±)-顺式-2-羟基-1-羟甲基-4-[5-甲基-2(1H),4(3H)-二氧代嘧啶-1-基]-(13a)和甲基(±)-顺式-4-(6-氨基嘌呤-9-基)-2-羟基-1-羟甲基环戊烷-1-羧酸酯(13b)。