... l,4-benzoxazines Richard С M. Butler, Christopher B. Chapleo*, Peter L. Myers, and Anthony P. Welbourn Department of Medicinal Chemistry, Reckitt and ... Heterocyclic Chem., 22, 177 (1985 ... aromatic H-7), 4.38 (s, 2, CHsPh), 4.20 (broad t, J = 4 Hz, 2, CH2), 3.30 (broad t, J = 4 Hz ...