Am,Feb.fif92.arm'}  -Antifebrin  and  Phenacetin  Derivatives,  103 
None  of  the  samples  contained  chlorine  or  bromine  in  quantity. 
Sample  2  contained  a  trace  of  chlorine,  and  the  two  commercial 
samples  contained  a  trace  of  non-volatile  matter,  but  were  otherwise 
of  unexpectedly  good  quality. 
ON  THE  ACTION  OF  ANTIFEBRIN,  AND  PHENACETIN 
DERIVATIVES.1 
By  H.  Aronsen. 
This  paper,  whilst  it  adds  but  little  to  our  practical  therapeutical 
knowledge,  is  one  of  those  contributions  to  pharmacology  by  the 
accumulation  of  which  a  firm  basis  for  therapeutics  will  in  time  be 
founded.  It  is  of  interest,  too,  as  illustrating  the  methods  by  which 
the  physiological  influence  of  those  groups  of  atoms,  of  which 
organic  compounds  consist,  is  being  determined. 
It  has  been  shown  by  Ehrlich  that  certain  kinds  of  coloring 
materials  taken  into  the  body  will  distinctly  color  the  brain  tissue ; 
but  that  the  introduction  into  the  coloring  compounds  of  a  sulpho- 
group  prevents  this.  Thus,  for  example,  sodium  alizarin  colors  the 
brain  yellow,  whilst  the  introduction  of  a  sulphonic  acid  group  into 
this  compound  entirely  prevents  this  action. 
Aronsen  brings  forward  experiments  to  show  that  in  like  manner 
the  influence  which  certain  antipyretics  have  in  lowering  tempera- 
ture in  fever  through  their  influence  on  the  nervous  centres,  is 
entirely  stopped  if  an  acid  group  be  introduced  into  their  com- 
position. 
Liebreich  has  shown  that  ac ety I -amido- salicylic  acid,  which  contains 
two  antithermic  groups,  antifebrin  and  salicylic  acid,  is  not  itself  an 
antipyretic,  and  the  ethyl  compound  of  this  body  is  likewise  not  a 
temperature  reducer.  In  both  these  bodies  the  carboxyl  group 
COOH  is  associated  with  the  benzol  component.  But  it  is  possible 
to  introduce  this  group  into  the  second  or  amido  component.  Only 
one  body  {acetanilid-acetic  acid)  in  which  such  introduction  has 
occurred  has  yet  been  examined,  and  it  has  been  found  by  Penzolt 
not  to  be  useful  as  an  antipyretic. 
Aronsen  points  out  that  this  influence  may  perhaps  be  due  to  the 
breaking  up  of  the  group  C6H5NHCO,  to  which  the  compound 
seems  to  owe  its  antipyretic  activity,  for  the  introduction  of  a  CH3 
1  Deut.  med.  Woch.,  Nov.  19,  1891  ;  the  Med.  Chronicle,  Jan.,  1892. 
