^^im^^Crystalline  alkaloid  of  Aconitum  Napellus.  237 
soluble  in  ether  and  alcohol,  most  soluble  in  benzene  and  chloro- 
form. They  melt  at  188-5°  (corr.).  Contrary  to  the  statements  of 
previous  observers,  who  found  aconitine  to  be  laevo-rotatory,  the 
authors  found  an  alcoholic  solution  to  the  dextro-rotatory  [a]D  -\- 
10-7.8°  ;  the  aqueous  solution  of  the  hydrobromide  is,  however, 
laevo-rotatory  [«]D  —  30-47°.  On  analysis,  the  pure  alkaloid 
afforded  results  which  agreed  best  with  the  formula  C33H45"N012. 
Two  crystalline  aurochlorides  were  obtained.  One  (C33H4.N012 
HAuClJ  melts  at  135-5°  (corr.);  the  other,  a  basic  aurochloride 
(C33H45N012AuCl3),  melts  at  129°  (corr.).  These  compounds  are 
obtained  without  difficulty,  and  afford  trustworthy  means  of  identi- 
fying aconitine.  Jhe  alkaloid  may  be  readily  recovered  from  them 
in  a  pure  state. 
Aconitine  is  not  appreciably  affected  by  heating  at  a  temperature 
below  its  melting  point,  but  at  this  temperature  it  is  gradually  con- 
verted into  the  uncrystallizable  base  aconine.  Prolonged  boiling  in 
aqueous  solution  induces  a  similar  change,  but  not  to  the  same 
extent,  unless  an  alkali  is  present.  Boiling  with  water  acidulated 
with  hydrochloric  acid  also  produces  decomposition  of  the  alkaloid. 
Dehydr aconitine  or  apoaconitine  is  a  base  differing  from  aconitine 
by  the  absence  of  a  molecular  proportion  of  water,  which  was  first 
obtained  by  Wright  and  Luff  by  acting  on  aconitine  with  acids.  Its 
existence  has,  however,  been  questioned  by  later  workers.  The 
authors  find  that  such  a  substance  may  be  readily  procured  by 
heafing  aconitine  with  saturated  aqueous  tartaric  acid  in  closed 
tubes,  as  recommended  by  Wright  and  Luff.  The  crystals  of  this 
substance  melt  at  186-5°  (corr.).  It  forms  crystalline  salts,  and  in 
other  respects  closely  resembles  the  parent  alkaloid.  The  results 
of  analyses  agree  well  with  the  formula  C33H43NOn.  Three  auro- 
chlorides were  obtained.  One  (C33H43NOnHAuCl4)  melts  at  141° 
(corr.).  This  salt,  when  crystallized  from  aqueous  alcohol,  becomes 
a  hydrate — 
(C33H43NOuHAuCl4H20) 
melting  at  129°  (corr.),  isomeric  with  aconitine  aurochloride,  into 
which,  indeed,  it  very  readily  changes.    The  third  aurochloride  is 
a  direct  compound  of  the  alkaloid  with  auric  chloride  (C!3Hl.5NOn 
AuCl3);  it  melts  at  147-5°  (corr.). 
An  amorphous  base  was  obtained  from  aconitine,  together  with 
benzoic  acid,  by  prolonged  heating  with  water  in  a  closed  tube.  It 
