258 
Active  Principle  of  Senna  Leaves. 
f  Am  Jour.  Pliarm. 
1       May,  1885. 
the  body  which  is  excreted  in  the  urine  and  which  gives  the  well- 
known  reddish  coloration  on  the  addition  of  an  alkali,  is  identical 
with  the  chrysoretin  of  Bley  and  Diesel.  Sawicky^  treated  the  watery 
infusion  of  the  leaves  with  acetate  of  lead,  decomposed  the  precipitate 
with  sulphuretted  hydrogen,  and  then  extracted  with  alcohol,  which 
took  up  all  the  active  principle.  On  evaporating  the  alcohol  he  ob- 
tained a  body  which  readily  combined  with  calcined  magnesia — the 
combination  so  formed  being  very  purgative.  His  conclusions  are  of 
importance,  viz.,  that  the  active  principle  is  an  organic  acid  soluble 
in  alcohol,  but  the  salts  of  which  are  quite  insoluble  in  that  men- 
struum. 
The  further  investigations,  two  in  number,  conducted  under  Buch- 
heim's  direction,  call  for  little  mention,  except  that  in  one  of  them  the 
active  principle  was  lirst  named  cathartic  acid. 
In  the  Monographic  der  Sennesblatter  "  of  Martins  we  find  a 
long  account  of  the  botanical  sources,  etc.,  of  the  senna  leaves,  but 
only  a  comparatively  short  portion  of  the  book  is  devoted  to  a  consid- 
eration of  their  chemistry.  He  examined  the  so-called  cathartin  care- 
fully, and  found  it  to  consist  of  a  mixture  of  inorganic  acids  and 
bases,  coloring  matter,  sugar,  etc.,  and  also  that  it  is  non-purgative. 
By  digesting  the  leaves  with  dilute  soda  solution,  adding  sulphuric 
acid,  and  allowing  the  sulphate  of  soda  to  crystallize  out,  he  obtained 
from  the  crystals,  on  shaking  them  up  with  ether,  a  yellow  body, 
which  he  says  consists  of  chrysoplianic  acid,  pha^oretin  and  aporetin 
(the  same  bodies  as  are  found  in  rhubarb).  The  chrysophanic  acid 
was  in  such  small  amount  that  he  had  not  enough  to  apply  the 
ordinarv  chemical  tests  to,  and  yet  lie  gives  as  his  opinion  that  it  is 
the  sole  active  constituent  in  the  leaves.  Chrysoretin  he  found  to  con- 
sist of  a  volatile  oil  and  coloring  matter. 
The  most  valuable  contribution  to  the  subject,  however,  is  that  of 
Kubly.^  He  evaporated  in  vacuo  the  watery  infusion  of  the  leaves  to 
the  consistence  of  a  syrup,  and  then,  by  adding  an  equal  quantity  of 
alcohol,  threw  down  the  inorganic  salts  and  mucus.  The  filtrate  was 
precipitated  with  large  excess  of  alcohol,  the  precipitate  dissolved  in 
water,  and  again  precipitated  with  alcohol.  This  was  repeated  again 
and  again,  hydrochloric  acid  being  finally  used  to  precipitate  albu- 
1 "  Qusedam  de  Efficaci  Folioruin  Seniise,"  etc.,  Dorpat,  1857. 
2  Ueber  das  wirksame  Princip  imd  einige  andere  Bestandtheile  der  Sen- 
nesbldtter,  1865. 
