416 
Digit  alin. 
Am.  Jour.  Pharm. 
Aug.,  1892. 
most  of  all  due  to  the  meritorious  investigations  of  Schmiedeberg,1 
the  principal  results  of  which  are  as  follows  : 
The  leaves  and  seed  of  Digitalis  purpurea  contain  a  preponderat- 
ing amount  of  an  inactive  glucoside  resembling  saponin  and  named 
digitonin.  They  also  contain  three  other  substances  which  possess 
the  characteristic  power  of  acting  upon  the  heart — crystallizable 
digitoxin  and  the  two  amorphous  glucosides,  digitalin  and  digita- 
lein.  Among  these  digitoxin  does  not  appear  to  be  suitable  for 
therapeutic  purposes,  partly  because  great  irregularity  in  its  absorp- 
tion is  to  be  apprehended  on  account  of  its  complete  insolubility  in 
water,  and  more  especially  because  the  investigations  of  Koppe2 
have  shown  that  it  also  gives  rise  to  very  unpleasant  and  even  dan- 
gerous effects.  On  the  other  hand  digitalin  and  digitalein  would 
be  very  suitable  for  practical  use  in  medicine  if  it  were  possible  to 
obtain  them  in  a  state  of  purity. 
Several  years  ago  I  commenced  a  further  investigation  of  the 
constituents  of  digitalis,  and  to  some  extent  the  results  arrived  at 
have  been  published.3  Digitonin  was  obtained  in  crystalline  con- 
dition, its  composition  was  ascertained,  the  products  of  its  trans- 
formation investigated,  and  it  was  further  proved  that  the  article 
then  met  with  in  commerce  under  the  name  of  crystallized  digitalin 
was  nothing  more  than  nearly  pure  digitonin,  or  in  other  words, 
a  substance  perfectly  worthless  in  regard  to  action  upon  the  heart, 
while  in  other  respects  directly  injurious,  as  will  be  shown  at  the 
end  of  this  communication. 
I  am  now  in  a  position  to  state  that  the  solution  of  the  main 
problem  has  been  achieved,  namely,  the  discovery  of  a  practically 
applicable  method  of  preparing  the  really  active  principle  of  digi- 
talis in  a  state  of  purity.  For  this  satisfactory  result  lam  essentially 
indebted  to  the  friendly  assistance  of  Professor  Boehm,  of  Leipzig, 
in  carrying  out  the  pharmacological  testing  of  a  large  number  of  my 
products,  by  which  I  was  led  to  the  right  path  in  my  inquiries. 
The  conclusions  thus  arrived  at  were  as  follows: 
(i)  Besides  digitonin  and  the  active  substances,  the  different 
kinds  of  commercial  digitalin  hitherto  known  generally  contain  two 
perfectly  amorphous  glucosides. 
1  Arch./.  Exper.  Pathol.,  3,  16. 
2  Arch.  Exper.  Pathol.,  3,  274. 
3  Ber.  d.  deutsch.  Chem.  Ges.,  xxiii,  1555  ;  xxiv,  339,  3951. 
