SEARCH Articles Figures Tables 1.3- Oxazin-6-ones 2.3- Diphenyl-5,6,7,8-tetrahydro 4H-1,3-Oxazin 4H-1,3-Oxazines Butoxycarbonylation Tetrahydro-1,3-oxazines Tetrahydro-1,4-oxazin-2-ones