CH 2 groups were replaced by NH or o and vice versa, nitrogroups became carboxylic acids and amides, OH groups became fluorine atoms; the list is extensive.
甲烷2组改为NH或O和反之亦然，硝基成为羧酸和酰胺，OH基团成为氟原子，该名单是广泛的。
2
Donors such as amine and phenolic groups, when positioned ortho to a nitro group, are always involved in intramolecular hydrogen bonding.