386 
Hydroquinone  and  Arbutin. 
(  Am.  Jour.  Pharm. 
\       Aug.,  1886. 
evaporated ;  the  residue  gave  no  crystals  with  chlorine  water,  but  a 
distinct  green  color  on  the  further  addition  of  ammonia.  Rabbits 
took  from  0'05  to  0*1  gm.  hydroquinone  without  bad  effect  j  cats  were 
killed  in  one  hour  by  0'2  gm.,  and  in  8  hours  by  0*1  gm.  of  hydro- 
quinone, after  tonic  and  clonic  convulsions.  The  presence  of  the  com- 
pound was  determined  in  the  blood,  urine  and  different  organs,  in- 
cluding the  brain,  but  not  in  the  muscles  or  in  the  feces.  The  excre- 
tion of  the  hydroquinone  from  the  human  body  seems  to  be  completed 
in  about  15  hours.  Frcehde's  reagent  was  found  to  be  the  most  deli- 
cate test,  though  not  conclusive  in  all  cases. 
[Similar  experiments,  made  with  arbutin,  showed  that  this  is 
excreted  with  the  urine  in  about  15  hours,  but  is  not  found  in 
the  feces.  Cats,  after  taking  1.0  gm.  of  arbutin  died  in  10  hours 
after  almost  constant  convulsions;  rabbits  took  the  same  dose 
without  ill  effects.  The  blood  and  most  of  the  organs  of  animals 
poisoned  with  arbutin,  showed  its  presence  more  or  less  distinctly. 
It  may  be  isolated  by  mixing  the  liquids  with  sulphurous  acid 
and  agitating  with  acetic  ether;  chloroform  and  ether  give  less 
reliable  results,  and  petroleum  benzin  does  not  dissolve  arbutin. 
On  boiling  the  liquids  with  4  per  cent,  sulphuric  acid,  hydroquinone 
is  produced. 
The  reactions  of  arbutin  are  as  follows:  Frcehde's  reagent  colors 
0.02  mgm.  arbutin  violet,  becoming  darker  and  green  from  the  mar- 
gin (like  hydroquinone).  Concentrated  sulphuric  acid  and  dilute 
solution  of  ferric  chloride,  of  each  1  drop,  strongly  heated,  color  0.02 
mgm.  arbutin  dark  chestnut-brown  (hydroquinone  is  colored  olive- 
green).  Silver  nitrate  with  1  mgm.  arbutin,  black  precipitate,  no 
odor.  Ferric  chloride,  diluted  and  warmed,  steel-blue  color  with  1 
mgm.  arbutin.  Bromine  vapors,  followed  by  ammonia,  gradually 
green  color,  changing  to  brown.  Chlorine  water  dissolves  colorless, 
changing  with  ammonia,  in  the  presence  of  more  than  0.1  mgm. 
arbutin,  to  green,  finally  brownish  (quinine,  which  gives  a  similar 
reaction,  is  not  taken  up  by  ether  from  the  acid  liquid).  Heated  with 
chlorine  water,  followed  by  a  little  ammonia  or  potassium  ferricya- 
nide,  more  than  0.02  mgm.  arbutin  gives  a  brown  to  brownish-violet 
color.  More  than  0.1  mgm.  arbutin  triturated  with  sugar  and 
moistened  with  sulphuric  acid,  gradually  turns  reddish,  then  blue, 
and,  finally,  green. 
J.  M.  M. 
