Abstract
A novel simple method, based on treatment with isoamyl nitrite (IAN) in DMSO without any added acid, to produce selective C(5)-nitrosation of aminopyrimidine derivatives is described. It proved to be suitable for a multigram scale and applicable to a larger range of pyrimidine derivatives, including amino-dialkoxypyrimidines, than the procedures previously known. Its scope is analyzed and some example on the usefulness of the newly prepared substances as intermediates in the synthesis of fused heterobicyclic derivatives of potential biological interest is presented.
Key words
electrophilic aromatic substitutions - heterocycles - C-nitrosation - nucleoside analogues - pyrimidines
References and Notes
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6 moved to 5.70 ppm (broad signal) assigned to the alcohol exchangeable proton.
22 A study on the nucleophilic substitution of methoxide groups of compounds 2 by different amines is currently under preparation in our laboratory and will be the subject of another report in near future. The easy substitution by the bulky 1-adamantylamino group is here anticipated in order to illustrate the synthetic potential of the products prepared by the nitrosation procedure described here.
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