THE  AMERICAN 
JOURNAL  OF  PHARMACY. 
APRIL,  1890. 
ON  VILLOSIN  AND  VILLOSIC  ACID, 
By  G.  A.  Krauss,  Ph.  G. 
From  a  letter  addressed  to  the  Editor;  read  at  the  Pharmaceutical  Meeting,  March  18. 
Since  my  departure  from  college  I  have  found  sufficient  time  to 
further  experiment  on  the  principle  to  which  I  designed  the  name 
Villosin.1  This  glucoside,  as  I  will  later  on  plainly  prove,  is  very 
easily  decomposed  into  glucose  and  villosic  acid.  Indeed  a  pro- 
longed boiling  of  its  solution  in  50  per  cent,  alcohol  decomposes 
villosin  gradually  as  the  alcohol  evaporates.  That  this  decreases 
the  amount  of  villosin  obtainable  is  well  understood. 
Recalling  the  process  of  its  preparation,  the  bark  is  exhausted 
with  alcohol,  sp.  gr.  0-820;  this  tincture  is  macerated  with  freshly 
precipitated  ferric  hydrate  until  all  tannin  has  been  removed;  the 
whole  is  then  filtered  and  expressed.  The  colorless  liquid  is 
evaporated  to  expel  all  the  alcohol,  as  a  trace  of  it  remaining  will 
cause  a  failure  in  obtaining  crystals.  After  having  filtered  off  the 
resin,  the  cool  and  clear  aqueous  solution  is  agitated  with  ether, 
sp.  gr.  0725.  Nearly  all  the  villosin  will  have  separated  in  3-5 
days  in  long  needle-shaped  crystals. 
On  account  of  its  instability,  I  only  obtained  about  18  grains  of 
villosin  from  3  lbs.  of  blackberry  root  bark,  the  greater  part  being 
decomposed  during  the  evaporation  of  the  alcoholic  filtrate  and 
filtered  off  as  a  white  resin  acid,  which  is  bitter,  and  soluble  in  alco- 
hol, ether  and  chloroform.  This  villosic  acid,  dissolved  in  ether, 
and  the  solution  evaporated  spontaneously,  is  obtained  crystalline. 
It  shows  the  same  color  reactions  as  villosin  viz:  (1)  Treated  with 
1  See  American  Journal  of  Pharmacy,  1889,  p.  605. 
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