This molecule features three fused rings that share a central carbon atom (C-1).
1. Ring A: a benzene ring with atoms numbered clockwise starting from C-1: C-1, C-2, C-3, C-4, C-5, and C-6. At C-5, a dimethylaminomethyl (-CH2-N(CH3)2) group is attached.
2. Ring B: a five-membered heterocycle containing one nitrogen and four carbon atoms, sharing atoms C-1 and C-2 with Ring A. Numbering clockwise from C-1, the atoms are: C-1, N-7, C-8, C-9, and C-2. All bonds in this ring are single except for the aromatic bond between C-1 and C-2. Additionally, C-9 is a chiral center with an R configuration and bears an amino (-NH2) group.
3. Ring C: a six-membered ring that shares atoms C-1 and C-6 with Ring A, and atoms C-1 and N-7 with Ring B. Numbering clockwise from C-1, the atoms are: C-1, C-6, C-10, C-11, C-12, and N-7. In this ring, C-12 is a carbonyl carbon forming a double bond with oxygen, and a double bond connects C-10 and C-11.