Zhou L, Coats SJ, Zhang H, Junxing S, Bobeck DR, Schinazi RF. Scaleable processes for the synthesis of (-)-β-D-2,6-diaminopurine dioxolane (Amdoxovir, DAPD) and (-)-β-D-2-aminopurine dioxolane (APD).
Tetrahedron 2012;
68:5738-5743. [PMID:
23162170 DOI:
10.1016/j.tet.2012.05.039]
[Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
An efficient and scalable synthesis of (-)-DAPD and (-)-APD has been developed. We discovered that t-butyl cyanoacetate can be used as a new additive for the sugar nucleoside base coupling step en route to DAPD with improved β-selectivity and an isolated yield four fold greater than the original process scale method. Using this new process, (-)-DAPD has been prepared on greater than 20 g scale. In the synthesis of (-)-APD, a key enzyme-catalyzed hydrolysis reaction afforded the water-soluble deprotected α-anomer while leaving the β-anomer completely untouched.
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