Fig. 3.
Frontier molecular Orbital (FMO) analysis of the C6 anion of the STS-bound tetraketide showing the highest occupied molecular orbital (HOMO) (A) and the lowest unoccupied molecular orbital (LUMO) (B); FMO analysis of the C2 anion of the CHS-bound tetraketide showing the HOMO (C) and the LUMO (D).