Sentences with phrase «heterocyclic aromatic rings»

Almost 90 percent of known active pharmaceutical ingredients contain one or more «heterocyclic aromatic rings», structures that contain atoms of at least two different elements.

Not exact matches

In order to avoid a second protonation at the physiological pH, a series of aminomethyl - substituted analogues, in which the second amino group was part of a heterocyclic ring or an aromatic system, were synthesized.