256 
Active  Principle  of  Senna  Leaves. 
Am.  Jour.  Pharm. 
May,  1885. 
cent. ;  and  as  I  estimate  that  at  least  half  the  strychnine  remained  in 
the  form  of  insoluble  nitrostrychnines,  this  may  be  regarded  as  repre- 
senting perhaps  nearly  20  per  cent,  of  the  material  actually  acted  on. 
When  fuming  nitric  acid  was  employed,  the  yield  was  rather  greater, 
for  12  per  cent,  of  potassium  salt  was  secured.  It  was,  however,  ac- 
companied by  another  substance  which  could  not  be  removed  except 
with  considerable  loss,  so  that  the  exact  amount  of  picrate  was  uncer- 
tain. 
It  is  singular  that  this  formation  of  trinitrophenol  in  a  reaction  that 
has  been  so  frequently  studied,  should  have  been  overlooked  hitherto. 
It  is  of  considerable  interest,  for  it  appears  to  indicate,  in  the  first 
place,  that  strychnine  contains  a  benzene-riug  of  carbon-atoms,  and 
secondly,  that  it  may  perhaps  contain  one  or  more  hydroxyl-groups  ; 
the  latter  inference  is  supported  by  the  behavior  of  strychnine  under 
the  action  of  the  alkaline  oxidizing  agents  used.  This,  if  correct,  is 
important,  as  there  are  so  few  cases  among  the  alkaloids  in  which  the 
manner  in  Avhich  the  oxygen  is  united  is  know^n. 
I  am  continuing  my  experiments  on  this  subject,  and  hope  to  be 
able  to  carry  on  the  work  without  interruption  in  the  future,  and  also 
to  extend  my  observations  to  other  alkaloids. — Jour,  Chem.  Soc, 
March,  1885,  pp.  139. 
THE  ACTIVE  PRINCIPLE  OF  SENNA  LEAVES.^ 
By  Ralph  Stockman,  M.B., 
Assistant  to  Professor  of  Materia  Medica,  Uaiversiti/  of  Edinburgh. 
Although  the  literature  of  the  senna  plant,  as  given  by  Martins,^  is 
verv  extensive,  and  dates  at  least  from  the  year  1496,  it  was  not  till 
1821  that  a  systematic  attempt  was  made  to  determine  the  nature  of 
the  active  principle,  and  the  other  constituents  of  the  leaves.  In  that 
year,  Lassaigne  and  Feneulle^  investigated  the  subject  very  fully,  and 
described  as  the  active  principle  a  body  which  they  named  cathartin. 
As  their  results  afterwards  became  the  subject  of  a  good  deal  of  dis- 
cussion and  contradiction,  it  may  be  interesting  to  describe  briefly  the 
method  by  which  they  obtained  cathartin. 
'  Read  at  a  meeting  of  the  North  British  Branch  of  the  Pharmaceutical 
Society,  February  18. 
2"  Versuch  einer  Monographie  der  Sennesblatter,"  Leipzig,  1857. 
3  Annates  de  Chimie  et  de  Physique,  xvi,  1821. 
