The noticeable width difference is most likely due to one not being a ring atom and having more flexibility. Nitrogens have the ability to be in hydrogen bonds and 1 is a very small score, given the exploitable features of N or O in interaction. The carbonyl oxygen (=O) has no interaction at all in this mode but does add to solubility of the entire molecule. The penetration of the fused bicyclo-[3.1.0]azahexane ring in the Mpro cavity can be noticed in the atomic interaction by the increase in C7 to C5 and then to the purple C2 and C41. Atomic distributional analysis provides detailed and useful information in computational molecular design.