All the Level 2 Chemistry subjects which are specific to a branch of chemistry (i.e. "Organic Chemistry 1", "Physical Chemistry 2" etc...) are from the old Chem major structure.
You cannot take any of these subjects as part of a new generation science degree.
The only way into a Chemistry major is by taking the following three Level 2 Chemistry subjects;
CHEM20018 Reactions and Synthesis
CHEM20020 Structure and Properties
CHEM20019 Practical Chemistry 2
So, if you want to also fulfill your med prereqs while pursuing a major in Medicinal Chemistry, your second year would have to look something like;
ANAT20006 Principles of Human Structure
BCMB20002 Biochemistry and Molecular Biology
PHYS20008 Human Physiology
CHEM20018 Reactions and Synthesis
CHEM20020 Structure and Properties
CHEM20019 Practical Chemistry 2
PHRM20001 Pharmacology: How Drugs Work
BREADTH
Thus, you would have to use up one of breadths for the year to make way for a science core.
Hope that helps!