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Unexpected deviation from diene behaviour of uracil amidine: towards synthesis of some pyrido[2,3-d]pyrimidine
Rupam Sarma1, Kalyan Jyoti Borah, Yuvaraj Dommaraju
1Medicinal Chemistry Division, North East Institute of Science and Technology (CSIR), Jorhat, 785006 Assam, India.
Abstract:
Condensation products obtained from the treatment of uracil amidine with preformed or in situ generated suitably substituted olefins unexpectedly undergo intramolecular cyclisation during silica gel chromatography to generate pyrido[2,3-d]pyrimidines. Various reaction conditions are studied and the altered nature of the uracil amidine molecule is further explored by reacting it with different suitably substituted alkenes.
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