English translation: ...a rest group with the formula...
Login or register (free and only takes a few minutes) to participate in this question.
You will also have access to many other tools and opportunities designed for those who have language-related jobs (or are passionate about them). Participation is free and the site has a strict confidentiality policy.
Explanation: Rest (Ger) = R = group (Eng) in this context.
The R terminology is used for groups with varying composition. The first group is labelled R1, the second R2, etc. This must be an extremely complex molecule to have such a lot of these. These R groups should then be specified somewhere, e.g. R1 = Cl, Br, I; R2= OH, CH3, C2H5 etc.