Am.  Tour.  Pharm.  \ 
July,  1 918.  > 
American  Acetylsalicylic  Acid. 
521 
EXAMINATION  OF  AMERICAN-MADE  ACETYLSALI- 
CYLIC ACID.1 
By  Paul  Nicholas  Leech. 
At  the  request  of  the  Council  on  Pharmacy  and  Chemistry,  the 
A.  M.  A.  Chemical  Laboratory  has  undertaken  examinations  of 
American-made  synthetic  drugs.  The  most  extensively  used  syn- 
thetic is  acetylsalicylic  acid  and  hence  an  investigation  of  this  product 
was  deemed  expedient. 
For  seventeen  years  acetylsalicylic  acid  was  protected  by  a 
United  States  Patent  (the  proprietors  were  not  give  a  patent  in 
other  countries)  and  sold  under  the  name  "Aspirin."  In  February, 
1917,  the  patent  expired,  and  since  then  a  number  of  firms  have 
engaged  in  the  manufacture  of  acetylsalicylic  acid,  selling  it  either 
as  such  or  as  aspirin,  modified,  of  course,  by  a  distinctive  firm  desig- 
nation. During  this  period  the  former  manufacturers  (The  Bayer 
Co.,  New  York,  in  past  years  called  Farbenfabriken  of  Elberfeld 
Co.,  New  York)  have  been  extensively  advertising,  both  to  physi- 
cians and  the  public,  the  alleged  superior  qualities  of  their  product. 
The  chemical  examination,  therefore,  was  concerned  chiefly  with 
tests  of  purity,  and  the  comparison  of  the  American  brands  with  the 
formerly  patented  product. 
In  European  countries,  acetylsalicylic  acid2  is  described  in  the 
various  pharmacopoeias  as  a  condensation  product  of  acetic  anhy- 
dride or  acetyl  chloride  with  salicylic  acid  (o-hydroxybenzoic  acid). 
Generally  the  test  of  identification  is  hydrolysis  of  acetylsalicylic 
acid  and  qualitative  tests  for  acetic  acid  and  salicylic  acid.  For 
purposes  of  purity  the  requirements  are  essentially  that  the  speci- 
men should  have  a  certain  melting  point,  should  show  absence  of 
salicylic  acid  by  means  of  ferric  chloride  (the  manipulations  for  the 
tests  are  variously  described)  and  leave  no  appreciable  ash.  The 
two  tests  of  purity  most  generally  employed,  however,  are  the  melt- 
ing point  and  the  reaction  with  ferric  chloride. 
1  The  Journal  of  Industrial  and  Engineering  Chemistry,  April,  1918. 
2  Unfortunately,  the  non-descriptive  name  "  aspirin  "  has  been  used  ex- 
tensively in  European  literature,  and  has  even  gotten  into  European  pharma- 
copoeias, instead  of  the  scientific  name  "  acetylsalicylic  acid." 
