Explanatory notes
… isoquinoline ring-system (whether or not hydrogenated), not further fused : 2933.41 - - Levorphanol (INN) and its salts … isoquinoline ring-system (whether or not hydrogenated), not further fused. Quinoline, isoquinoline and their … and the two methyl groups of phenazone); and (d) have further substitutions of hydrogen atoms only (e.g., a …