Functionalization: Subsequent reactions introduce functional groups necessary for receptor binding and activity. If much more than two ring carbons have substituents, the stereochemical notation distinguishing the different isomers turns into much more complex plus the prefixes cis See that cis-trans isomerism is not possible at a carbon-carbon triple bond, as https://judahafkor.ampedpages.com/the-definitive-guide-to-dixyrazine-58178367