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| Section2 = | Section3 = }} 4-Methylimidazole (4-MeI or 4-MEI) is a heterocyclic organic chemical compound with molecular formula – or . It is formally derived from imidazole through replacement of the hydrogen in position 4 by a methyl group. It is a slightly yellowish solid. 4-MeI may be formed in the browning of certain foods through the Maillard reaction between carbohydrates and amino-containing compounds. In particular, it is found in roasted foods, grilled meats, coffee and in types of caramel coloring produced with ammonia-based processes.〔〔http://oehha.ca.gov/public_info/facts/pdf/4MEIfacts_021012.pdf〕 It may arise also by fermentation. ==Preparation and structure== 4-MeI may be prepared using the Debus-Radziszewski imidazole synthesis, by reacting methylglyoxal with ammonia and formaldehyde. It may also be prepared by the reaction of hydroxyacetone and formamide in ammonia. Small energy difference separates 4-methylimidazole from its tautomer 5-methylimidazole.〔G.-S. Li, M. F. Ruiz-López, B. Maigret "Ab Initio Study of 4(5)-Methylimidazole in Aqueous Solution" J. Phys. Chem. A, 1997, vol. 101, pp 7885–7892. 〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「4-Methylimidazole」の詳細全文を読む スポンサード リンク
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