N-Boc-2, 5-bis(trimethylsilyl)pyrrolidine 4 was synthesized from the reaction of N-Boc-pyrrolidine 1 with trimethylsilyl chloride (TMSCl) at optional temperature in one-pot in good yield.
1-Boc-吲哚-2-硼酸衍生物是一类重要的有机中间体,广泛用于卤代芳烃参与的Suzuki-Miyaura偶联反应,从而构建复杂吲哚化合物.为了合成这类吲哚硼酸衍生物,以邻甲基硝基苯的衍生物(1a-1g)为起始原料,通过与DMFDMA、THP进行反应并进行浓缩...1-Boc-吲哚-2-硼酸衍生物是一类重要的有机中间体,广泛用于卤代芳烃参与的Suzuki-Miyaura偶联反应,从而构建复杂吲哚化合物.为了合成这类吲哚硼酸衍生物,以邻甲基硝基苯的衍生物(1a-1g)为起始原料,通过与DMFDMA、THP进行反应并进行浓缩结晶合成对应的烯胺;烯胺与还原剂进行还原关环得到吲哚衍生物;吲哚衍生物与二碳酸二叔丁酯反应完成对吲哚的保护;Boc保护的吲哚衍生物在低温无水无氧条件下与硼酸三异丙酯、LDA反应引入硼酸基团共4步反应,成功合成了包括6-苄氧基-1-Boc-吲哚-2-硼酸在内的共计7种吲哚硼酸衍生物(5a-5g),其结构经^1H NMR、^13 C NMR、IR和MS表征.展开更多
Solubility of 2-amino-6-chloropurine in Mitsunobu solvents could be significantly improved after its exocyclic amino group is protected via N-tert-butoxycarbonylation.The bis-Boc protected 2-amino-6-chloropurine also ...Solubility of 2-amino-6-chloropurine in Mitsunobu solvents could be significantly improved after its exocyclic amino group is protected via N-tert-butoxycarbonylation.The bis-Boc protected 2-amino-6-chloropurine also shows excellent activity and N9 selectivity in the coupling with various alcohols by a Mitsunobu reaction.Then,a new practical and efficient method is established for the synthesis of penciclovir(PCV) from bis-Boc-2-amino-6-chloropurine 9 and the side chain of 5-(2-hydroxyethyl)-2,2-dimethyl-1,3-dioxane 5—the latter being a more easily prepared cyclic precursor of the diacetate side chain used in the conventional process.The coupling of 9 with 5 proceeded regioselectively at a N9 position of purine derivative for a good yield under Mitsunobu conditions.展开更多
采用碳端到氮端依次连接策略,以天冬氨酸、甘氨酸、精氨酸为起始原料,以HBTU为缩合剂,Asp(OBzl)-OAllyl顺次分别与Boc-甘氨酸和Cbz-Arg(Cbz)2偶联生成碳端和氮端保护的RGD。进一步在N-甲基吗啉存在下以Pd(PPh3)4催化脱去烯丙基,得到目...采用碳端到氮端依次连接策略,以天冬氨酸、甘氨酸、精氨酸为起始原料,以HBTU为缩合剂,Asp(OBzl)-OAllyl顺次分别与Boc-甘氨酸和Cbz-Arg(Cbz)2偶联生成碳端和氮端保护的RGD。进一步在N-甲基吗啉存在下以Pd(PPh3)4催化脱去烯丙基,得到目标产物。中间产物和目标产物的分离、提纯采用重结晶和柱层析法,应用1 H NMR,13C NMR和MS等对其结构进行了表征。展开更多
基金the National Natural Science Foundation of China (No 29772004).
文摘N-Boc-2, 5-bis(trimethylsilyl)pyrrolidine 4 was synthesized from the reaction of N-Boc-pyrrolidine 1 with trimethylsilyl chloride (TMSCl) at optional temperature in one-pot in good yield.
文摘1-Boc-吲哚-2-硼酸衍生物是一类重要的有机中间体,广泛用于卤代芳烃参与的Suzuki-Miyaura偶联反应,从而构建复杂吲哚化合物.为了合成这类吲哚硼酸衍生物,以邻甲基硝基苯的衍生物(1a-1g)为起始原料,通过与DMFDMA、THP进行反应并进行浓缩结晶合成对应的烯胺;烯胺与还原剂进行还原关环得到吲哚衍生物;吲哚衍生物与二碳酸二叔丁酯反应完成对吲哚的保护;Boc保护的吲哚衍生物在低温无水无氧条件下与硼酸三异丙酯、LDA反应引入硼酸基团共4步反应,成功合成了包括6-苄氧基-1-Boc-吲哚-2-硼酸在内的共计7种吲哚硼酸衍生物(5a-5g),其结构经^1H NMR、^13 C NMR、IR和MS表征.
文摘Solubility of 2-amino-6-chloropurine in Mitsunobu solvents could be significantly improved after its exocyclic amino group is protected via N-tert-butoxycarbonylation.The bis-Boc protected 2-amino-6-chloropurine also shows excellent activity and N9 selectivity in the coupling with various alcohols by a Mitsunobu reaction.Then,a new practical and efficient method is established for the synthesis of penciclovir(PCV) from bis-Boc-2-amino-6-chloropurine 9 and the side chain of 5-(2-hydroxyethyl)-2,2-dimethyl-1,3-dioxane 5—the latter being a more easily prepared cyclic precursor of the diacetate side chain used in the conventional process.The coupling of 9 with 5 proceeded regioselectively at a N9 position of purine derivative for a good yield under Mitsunobu conditions.
文摘采用碳端到氮端依次连接策略,以天冬氨酸、甘氨酸、精氨酸为起始原料,以HBTU为缩合剂,Asp(OBzl)-OAllyl顺次分别与Boc-甘氨酸和Cbz-Arg(Cbz)2偶联生成碳端和氮端保护的RGD。进一步在N-甲基吗啉存在下以Pd(PPh3)4催化脱去烯丙基,得到目标产物。中间产物和目标产物的分离、提纯采用重结晶和柱层析法,应用1 H NMR,13C NMR和MS等对其结构进行了表征。
