PROXIMATE CONSTITUENTS OF THE ANIMAL BODY 55 



Benzyl alcohol 

 Benzylaldchydc 

 Benzoic acid 



C 6 H 5 .CH 2 OH. 



C 6 H 5 .CHO. 



C 6 H 5 .COOH. 



Of the disubstitution compounds, we need only mention the following : 

 The dihydroxybenzenes : 



Pyrocatechin or catechol Resorcinol Hydroquinone 



OH 



OH 



OH 



OH 



OH 



ortho- 



meta- 



Salicylic acid (o-hydroxybenzoic acid) C 6 H 6 x 



Tyrosin (parahydroxyphenyl a-alanine) : 



OH 



COOH. 



CH 2 .CH(NH 2 )COOH. 



Examples of tri&ubstitution derivatives of benzene are : 



OH 



OH 



Pyrogallol 



OH 



OH 



Homogentisic acid 



CH,.COOH 



Adrenaline 



Picric acid 



OH 



CH.OH 



CH 2 .NH(CH 3 ) 

 OH 

 N0 2 | N0 2 



