C CHEMISTRY; METALLURGY
C07 ORGANIC CHEMISTRY
C07D HETEROCYCLIC COMPOUNDS
265/00 Heterocyclic compounds containing six-membered rings having one nitrogen atom and one oxygen atom as the only ring hetero atoms
C07D265/04 1,3-Oxazines; Hydrogenated 1,3-oxazines
C07D265/06 not condensed with other rings
C07D265/08 having one double bond between ring members or between a ring member and a non-ring member
C07D265/10 with oxygen atoms directly attached to ring carbon atoms