Is there a new antibiotic between rifampicin and vinorelbine? Or a new polymer between polyester and propofol?

 

There are various places on rifampicin where a methyl, aldehyde, or carbonyl group could be added. It seems the main difference between the two is that the alcohol groups in rifampicin get replaced with H in vinorelbine. It's sort of like the way ethylene exists between ethane and acetylene. 

Molecules with similar structures tend to have similar properties. This can be clearly seen with opioids and antibiotics in the penicillin family. 

I wonder if there's anything interesting between polyester and propofol. The C11 gap in the CHO group is the smallest gap molecule in my dictionary.