Am.  Jour.  Pharro. 
Jan.,  1885. 
Crysta  I  Used  Colchich  i  e . 
35 
CRYSTALLISED  COLCHICINE. 
By  a.  H0UDE8. 
Three  kilos,  of  colchicum  seeds  were  exhausted  with  100  kilos,  of 
alcohol  of  96°,  the  liquid  filtered,  the  alcohol  distilled  off,  and  the 
residue  treated  repeatedly  with  a  5  per  cent,  solution  of  tartaric  acid, 
which  dissolves  out  the  colchicine,  but  leaves  fatty  and  resinous  matters 
undissolved.  The  filtered  solution  was  then  agitated  with  chloroform, 
the  chloroform  removed  by  evaporation,  and  the  crude  product  purified 
by  repeated  crystallization  from  a  mixture  of  equal  parts  of  chloroform, 
alcohol,  and  benzene.  The  yield  from  the  seeds  is  about  3  grams  per 
kilo.,  whilst  that  fioni  the  bulbs  is  only  0*4  gram  per  kilo. 
The  colchicine  thus  obtained  forms  nodular  groups  of  colorless 
prisms,  slightly  soluble  in  water,  glycerol,  and  ether,  but  soluble  in  all 
proportions  in  alcohol,  benzene,  and  chloroform.  It  has  a  very  bitter 
taste,  and  an  alkaline  reaction,  contains  nitrogen,  and  burns  without 
residue.  It  is  hydrated,  and  melts  at  93°,  but  after  drying  at  100°, 
the  melting  point  rises  to  163°.  A  solution  of  colchicine  does  not 
reduce  an  alkaline  copper  solution,  but  after  prolonged  boiling  with 
dilute  sulphuric  acid,  it  reduces  it  immediately,  and  in  this  respect  re- 
sembles solanine.  Colchicine  combines  with  certain  organic  acids,  but 
is  decomposed  when  brought  in  contact  with  strong  acids. 
Concentrated  or  dilute  inorganic  acids  dissolve  colchicine  and  form 
a  citron-yellow  solution  ;  nitric  acid  produces  a  transient  violet  colora- 
tion. Solutions  of  colchicine  are  precipitated  by  potash  and  soda,  but 
not  by  ammonia.  Tannin  produces  a  white  precipitate  soluble  on  heat- 
ing; platinum  tetrachloride,  an  orange-yellow  precipitate;  an  aqueous 
solution  of  iodine,  a  kermes-red  precipitate  ;  mercuric  potassium  iodide, 
a  yellow  precipitate  ;  iodine  in  potassium  iodide,  a  maroon-yellow  pre- 
cipitate. 
Colchicine  exerts  a  physiological  efJ'ect  only  in  relatively  large  doses. 
Respiration  and  the  functions  of  the  heart  are  considerably  modified, 
and  the  general  effect  is  a  state  of  collapse,  with  stupor,  but  without 
insensibility.  —  Compt.  rend.,  xcviii  ,  pp.  4442-1444;  Jour.  Cliem. 
Soc,  pp.  1055-1056,  October,  1884. 
