Highly Enantioselective Synthesis of Chiral Cyclopropyl Nucleosides via Catalytic Asymmetric Intermolecular
Jian-Ping Li1, Guo-Feng Zhao1, Hai-Xia Wang1
1Henan Key Laboratory of Organic Functional Molecules and Drugs Innovation, School of Chemistry and Chemical Engineering, Henan Normal University , Xinxiang, Henan 453007, China.
Abstract:
An efficient route to construct chiral cyclopropyl purine nucleoside analogues has been established via the catalytic asymmetric Michael-initiated ring-closure reactions of α-purine acrylates with α-bromo-carboxylic esters. Using (DHQD)2AQN as the catalyst, various chiral cyclopropyl purine nucleoside analogues with a chiral quaternary stereocenter were obtained in 72-98% yields, excellent diastereoselectivities, and 93-97% ee. Through simple functional group transformations, diverse chiral cyclopropyl purine nucleosides with hydroxymethyl group or carboxyl group were obtained.
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