Qinolone Analogues 4. Synthesis ofÅ@1-Methyl-3-trifluoromethylpyridazino[3,4-b]quinoxalin-4(1H)-ones
作者:Yoshihisa Kurasawa、Izumi Matsuzaki、Waka Satoh、Yoshihisa Okamoto、Ho Sik Kim
DOI:10.3987/com-01-s(k)38
日期:——
5-dihydro-3-trifluoromethylpyridazino[3,4-b]quinoxaline-4-carboxylates (15a, b), whose oxidation with nitrous acid afforded the 1,4-dihydro-4-hydroxy-3-trifluoromethylpyridazino[3,4-b]quinoxaline-4-carboxylates (16a,b), respectively. The reaction of compounds (16a, b) with 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) provided the 1,5-dihydro-3-trifluoromethylpyridazino[3,4-b]quinoxalin-4-ols (17a, b), whose
喹喔啉 N-氧化物 (7a, b) 与 4,4,4-三氟乙酰乙酸酯反应得到 1,5-二氢-3-三氟甲基哒嗪并[3,4-b]喹喔啉-4-羧酸酯 (15a, b),其与亚硝酸的氧化分别得到 1,4-dihydro-4-hydroxy-3-trifluoromethylpyridazino[3,4-b]quinoxaline-4-carboxylates (16a,b)。化合物 (16a, b) 与 1,8-二氮杂双环[5.4.0]-7-十一碳烯 (DBU) 反应得到 1,5-dihydro-3-trifluoromethylpyridazino[3,4-b]quinoxalin-4-ols (17a,b),其与溴酸钠氧化分别产生1-甲基-3-三氟甲基哒嗪并[3,4-b]喹喔啉-4(1H)-酮(6a,b)。