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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Spirodihydantoin is a minor product of 5-hydroxyisourate in urate oxidation
Hongbin Yu1, Jacquin C Niles, John S Wishnok
1Biological Engineering Division and Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Room 56-731A, Cambridge, Massachusetts 02139, USA.
Abstract:
[reaction: see text] Spirodihydantoin is a minor product from oxidation of uric acid ( approximately 0.15% yield), while spiroiminodihydantoin is a major product from oxidation of 8-oxo-7,8-dihydroguanine (37% yield, pH 10.2). High pH and temperature favor the formation of both spiro compounds. (18)O labeling experiments and in situ generation and decomposition of 5-hydroxy-N7-methylisouric acid indicate that spirodihydantoin and allantoin and spiroiminodihydantoin and guanidinohydantoin are products of 5-hydroxyisourate and 5-hydroxy-8-oxo-7,8-dihydroguanine intermediates, respectively.
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