Aj;nu°^i9i3™  }  Digitalis  Gluamdes  and  Allied  Drugs.  2g 
these  "  digitaloin  "  and  "  digitalacrin  a  and  /?."  The  residue,  which 
was  insoluble  in  ether,  was  extracted  with  water,  whereby 
"  digitaletin  "  remained  and  "  digitalin  Walz  "  dissolved.  Walz 
describes  his  digitalin  as  a  yellowish,  amorphous  substance,  which 
is  distinguished  from  the  digitalin  of  Homolle  by  being  soluble 
in  water  and  only  with  difficulty  soluble  in  chloroform.  The 
digitalin  of  Walz  formerly  also  bore  the  name  of  "  German  digi- 
talin," but  it  should  be  noted  that  it  is  not  identical  with  the 
digitalinum  Germanicum  at  present  on  the  market,  as  the  latter 
is  prepared  from  digitalis  seeds.  However,  Walz  in  the  course 
of  his  studies  on  digitalin  altered  his  method  of  preparation,  and 
later  (Cf.  Canstatt's  Jahresbericht  1850,  Vol.  10,  p.  22)  he  de- 
scribes his  digitalin  as  a  crystalline  body,  very  similar  to  the  digitalin 
of  Homolle,  soluble  with  difficulty  in  water  and  melting  at  1750. 
Nativelle  isolated  three  substances  from  digitalis  leaves,  namely 
digitalein  Nativelle,  a  glucoside  soluble  in  water,  prepared  by 
extraction  with  water  and  subsequent  purification,  and  digitalin 
Xativelle,  ( digitaline  cristallisee) ,  soluble  in  alcohol  and  chloroform, 
obtained  by  extraction  with  alcohol,  and  thirdly  digitin  Nativelle, 
soluble  in  alcohol  and  practically  insoluble  in  chloroform;  this 
substance,  on  account  of  its  physiological  inactivity,  he  at  first 
named  "  substance  cristallisee  inerte." 
Schmiedeberg  obtained  from  digitalis  leaves  the  first  prepara- 
tion of  digitalis  which  had  well  defined  chemical  characteristics 
and  was  physiologically  active,  viz.,  digitoxin  Schmiedeberg;  he 
first  extracted  the  drug  with  water  and  then  with  alcohol  (50  p.  c), 
the  alcoholic  extract  was  cleared  with  lead  acetate,  and  after  re- 
moving the  lead  which  had  dissolved,  evaporated  the  solution  to 
dryness,  and  extracted  the  residue  with  chloroform  and  distilled 
off  the  chloroform.  After  purifying  the  residue  with  ether  and 
animal  charcoal,  as  well  as  recrystallising  it  several  times  from 
alcohol,  he  obtained  a  pure  hydrated  preparation,  melting 
at  145 0  C.  For  anhydrous  digitoxin  he  gave  the  empirical  formula 
C21  H.3„  Or.  Digitoxin  Schmiedeberg  is  now  simply  called  "  digi- 
toxin." Kiliani,  who  has  made  an  exhaustive  study  of  digitoxin  and 
its  decomposition  products  found  that  this  glucoside  corresponded 
to  the  formula  Cu  H54  01T,  and  on  hydrolysis  yielded  digitoxigenin 
and  digitoxose.  It  forms  white  crystals,  which  are  readilv  soluble 
in  alcohol  and  chloroform,  but  only  with'  difficulty  soluble  in  water 
and  ether. 
