Am.  Jour.  Pharm. 
June,  1893. 
Specimens  of  Aconitine. 
301 
For  medicinal  purposes,  nothing  should  in  future  be  employed  as 
aconitine  but  the  pure  crystalline  alkaloid  melting  at  188-1890,  and 
having  the  other  characteristic  properties  recorded  in  Part  I  (Trans., 
1 89 1,  59,  271)  of  this  enquiry  (see  also  on  this  point,  Pharm.  J., 
3,  23,  765). 
Of  the  specimens  now  examined,  only  two  (13,  14)  approach  this 
standard,  and  are  entitled  to  be  called  aconitine.  It  is  clear  from 
the  results  which  are  here  recorded  that  the  fact  that  a  specimen  of 
this  alkaloid  is  crystalline  cannot  alone  be  accepted  as  sufficient 
evidence  of  purity,  as  some  physiologists  have  assumed.  In  the  case 
of  the  salts,  the  crystalline  nature  of  the  specimens  is  no  criterion 
that  the  substance  is  an  aconitine  compound,  since  the  salts  of  isacon- 
itine  are  also  crystalline. 
It  has  already  been  remarked  that  most  of  the  specimens  described 
in  this  paper  were  collected  some  years  ago,  and  since  then,  especially 
during  the  last  two  years,  a  marked  improvement  has  occurred  in 
the  quality  of  commercial  aconitine.  It  is  now  possible  to  purchase 
in  commerce  a  nearly  pure  crystalline  aconitine,  represented  by 
specimens  (13)  and  (14),  although  the  crude,  amorphous  alkaloid  is 
still  largely  prepared  and  sold,  because  this  satisfies  the  present 
requirements  of  the  British  Pharmacopoeia. 
Until  now,  it  has  not  been  possible  to  make  anything  approach- 
ing to  a  chemical  examination  of  commercial  aconitine,  since  the 
nature  and  properties  of  its  chief  constituents  were  either  unknown 
or  open  to  doubt.  Even  now  it  is  not  possible  to  make  a  com- 
plete examination,  as  there  is  certainly  one,  probably  two  alkaloids 
which  still  require  investigation,  making  in  all  four,  or  possibly  five, 
distinct  natural  alkaloidal  products  from  A.  Napellus. 
No  method  is  at  present  known  for  the  quantitative  determination 
of  the  highly  toxic  alkaloid  aconitine.  Now  that  isaconitine  is 
known  to  be  a  constituent  of  the  plant,  and  since  it,  like  aconitine, 
furnishes  benzoic  acid  when  hydrolysed,  the  method  suggested  by 
Wright  for  the  estimation  of  aconitine  in  the  crude  alkaloid,  by  cal- 
culating from  the  weight  of  benzoic  acid  obtained  on  hydrolysis, 
can  no  longer  be  accepted  as  valid. — Research  Laboratory  of  the 
Pharmaceutical  Society,  London. — Jour.  Chem.  Soc,  1893,  pp. 
491-495. 
