Approximations for zeros of Hermite functions

A novel process is provided for producing a nucleoside, such as cytarabine, or a nucleoside analogue, comprising the step of reacting 2,2'-O-cyclonucleoside or an analogue thereof with an amine. Preferably, the process is conducted in the presence of an aqueous solvent. A novel process for the production of the precursor 2,2'-O-cyclonucleoside compounds and pharmaceutically acceptable salts thereof is also provided which comprises reacting a 2,3'-O-diaikylstannylene nucleoside compound with an amine in the presence of a sulfonyl compound. Cytarabine is a known antineoplastic and antiviral agent.

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