PTOMAINES 373 



more widely distributed, and occurs in seeds and fruits of 

 a very large number of plants, such as Pinus cembra, Areca 

 Catechu (nut), Cocos nucifera (endosperm), Acorus calamus 

 (root), Fagus silvatica, Cannabis saliva and C. indica, Humulus 

 Lupulus, etc. 



Neurine does not occur in plants, but is produced in putre- 

 fying fish and meat. " Muscarine " and neurine are both very 

 poisonous, whereas choline is less so. 



All these substances are strong bases, and answer the 

 general reactions for alkaloids. 



A few other bases of comparatively simple constitution 

 which occur in plants may here be mentioned. 



Trimethylamine, (CH3)3N, is a very volatile substance 

 which occurs in the seeds of Mercurialis annua and in the 

 flowers of Crataegus Oxyacantha, Pyrus Aucuparia, and many 

 other plants, and is given off from the leaves of Chenopodium 

 Vulvaria. It is also readily produced from choline and 

 betaine, and is, therefore, commonly produced from putrifying 

 animal or vegetable matter containing lecithin. 



»x 



Parahydroxyphenylethylamine, HO^ ^CHaCHgNHg, 



is a substance occurring in ergot, which has a marked pressor 

 action on the circulation, and causes contraction of the uterus. 

 Its close relationship to tyrosine, from which it can be ob- 

 tained by loss of carbon dioxide, is of interest — 



HO<^ ^ CHjCHNHjCOOH -> HOC >CH2CH2NH2 + COj 



Tyrosine Hydroxyphenylethylamine 



Hordenine, Ho/ NcH2CH2N(CH3)2, is the dimethyl 

 derivative of the previous compound, and occurs in barley. 



The fact that all nitrogenous bases form crystalline deriva- 

 tives with such substances as platinic or auric chlorides, or with 

 picric or picrolonic acids is frequently made use of for isolating 

 or identifying small quantities of these substances (see choline, 

 lecithin, p. 53) ; since the derivatives produced can, as a rule, 

 be identified by their crystalline form and melting-point ; 



