Am.  Jour.  Pharm. 
June,  1888. 
Asarone. 
305 
ascribed  to  it.  On  oxidation  it  yielded  a  neutral,  crystalline  sub- 
stance ;  this  was  subsequently  investigated  by  IStaats,  and  although  his 
work  confirms  the  author's  results  in  general,  the  sample  which  he  an- 
alyzed does  not  seem  to  have  been  pure. 
In  the  present  paper,  the  chemical  nature  of  asarone  is  determined 
by  the  study  of  its  products  of  oxidation,  which  are  a  neutral  sub- 
stance, an  acid,  and  a  compound  derived  from  the  latter  by  the  elimi- 
nation of  a  CO2  group.  Two  methods  are  employed.  In  the  first, 
the  asarone  (12  grams)  is  dissolved  in  strong  acetic  acid  (40 
grams)  and  potassium  dichromate  (6  grams)  added;  the  mix- 
ture is  then  carefully  heated  until  it  turns  green.  On  cooling 
and  adding  water,  needle-shaped  crystals  separate  together  with  a  red- 
dish-brown resinous  substance.  The  crystals  are  neutral,  of  a  silky 
lustre,  soluble  in  hot  water,  ether,  light  petroleum,  and  benzene.  They 
melt  at  114°,  but  sublime  even  at  100°.  The  analysis  agrees  with  the 
formula  CioIIi2C^4-  Better  results  are  obtained  by  the  use  of  potassium 
permanganate  solution  (40  grams  in  750  grams  water),  which  is  added 
drop  by  drop  to  a  warm  solution  of  asarone  (10  grams  in  450  grams 
water).  The  compound  C10H12O4  is  extracted  from  the  filtrate  by 
means  of  ether ;  the  alkaline  solution  is  then  evaporated  to  dryness, 
and  the  residue  either  extracted  with  hot  alcohol  or  decomposed  with 
hydrochloric  acid,  and  then  extracted  with  alcohol.  In  the  first  case 
the  potassium  salt  of  a  new  acid  separates  out  from  the  hot  spirit,  in 
the  second  the  new  acid  itself  Carbonic,  formic,  oxalic,  and  acetic 
acids  are  formed  at  the  same  time.  When  the  operation  is  conducted 
as  described,  the  quantity  of  acid  formed  is  much  larger  than  that  of 
the  neutral  substance,  but  the  reverse  is  the  case  when  a  mixture  of 
asarone  (5  grams)  and  finely-powdered  permanganate  (7*5  grams)  is 
added  in  small  portions  at  a  time  to  boiling  water.  The  acid,  C10H12O5, 
crystallizes  in  needles,  which  are  soluble  in  benzene,  light  petroleum, 
alcohol,  and  boiling  water.  It  melts  at  144°,  and  boils  at  about  300°  ; 
it  has  distinctly  acid  properties,  decomposing  carbonates.  Its  silver 
salt,  prepared  from  the  potassium  salt,  is  tolerably  stable  under  the 
influence  of  air  and  light. 
The  neutral  substance,  C10H12O4,  was  found  to  be  the  aldehyde  of 
the  acid  C10N12O5,  as  was  proved  by  the  oxidizing  it  with  permangan- 
ate, when  it  was  converted  into  the  acid.  Neither  of  these  substances, 
however,  has  the  properties  of  an  unsaturated  compound  so  character- 
istically exhibited  by  asarone.    That  the  neutral  substance  is  an  aide- 
