First synthesis of 4'-selenonucleosides showing unusual Southern conformation
Lak Shin Jeong1, Dilip K Tosh, Hea Ok Kim
1Laboratory of Medicinal Chemistry, College of Pharmacy, Ewha Womans University, Seoul 120-750, Korea. lakjeong@ewha.ac.kr
Organic Letters
|December 20, 2007
Abstract:
The first synthesis of 4'-selenonucleosides was achieved using a Pummerer-type condensation as a key step. All stereoelectronic effects shown in 4'-oxonucleosides were overwhelmed by the size of selenium and steric interactions, driving the conformation to the C2'-endo/ C3'-exo twist (Southern) conformation.
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