<unk>  can be divided into three groups according to the degree of substitution.<unk>  belonging to the same group behave similarly in their chemical properties. Monosubstituted<unk>  and so-called asymmetrically disubstituted<unk> , where (only) two hydrocarbon groups are bonded to the same nitrogen atom are colorless liquids. Aliphatic monosubstituted and asymmetrically disubstituted<unk>  are very water soluble, strongly alkaline and good reducing agents. Aromatic monosubstituted and asymmetrically disubstituted<unk>  are poorly soluble in water, less basic and weaker reducing agents. 2 For the preparation of aliphatic<unk> , the reaction of<unk> with alkylating compounds such as alkyl halides is used, or by reduction of nitroso derivatives. Aromatic<unk>  are prepared by reducing aromatic diazonium salts. In symmetric disubstituted<unk> , a hydrocarbon group is bonded to each of the<unk> nitrogen atoms. Like asymmetrically disubstituted<unk> , they are liquids, but their boiling points are typically higher. In particular, the aliphatic compounds are basic and reducing agents and are soluble in water. Aromatic symmetric disubstituted<unk>  are not soluble in water. Symmetrically disubstituted<unk>  are prepared by reducing nitro compounds under basic conditions or by reducing the azines. Tri- or tetrasubstituted aliphatic<unk>  are water-insoluble weakly basic compounds. The corresponding arylhydrazines are solid colorless substances which are insoluble in water and substantially not basic. They react with concentrated sulfuric acid to form a violet or dark blue compounds.
Hydrazines
Sulfonamide 
Thyroid blocker
Psychotropic alkylamines
Prostaglandin inhibitors
Steroid ester
Antimanic drugs
Anthopleurin