THE  AMERICAN 
JOURNAL  OF  PHARMACY. 
MARCH,  1883. 
ON  THE  COMPOSITION  AND  SOLUBILITY  OF  COM- 
MEECIAL  SULPHATE  OF  STRYCHNINE. 
By  M.  W.  Coleman. 
Bead  at  the  Phafmaceutical  Meeting^  February  20th. 
My  attention  having  been  directed  to  a  brief  abstract  of  an  investi- 
gation by  Rammelsberg/  concerning  the  composition  of  sulphate  of 
strychnine  of  German  commerce  ;  and  as  the  results  attained  by  this 
eminent  chemist  are  considerably  at  variance  with  the  formula  whicli 
has  been  assigned  to  the  salt  adopted  by  the  United  States  Pharmaco- 
poeia and  some  other  works,  it  seemed  desirable  to  verify,  or  determine 
anew,  the  composition  of  the  sulphate  of  strychnine  of  the  American 
manufacturers,  and  to  extend  the  investigation  to  the  determination  of 
its  solubility  and  other  physical  characters.  With  this  purpose  in  view, 
a  series  of  experiments  was  performed  in  the  chemical  laboratory  of  the 
Philadelphia  College  of  Pharmacy. 
According  to  Rammelsberg  the  sulphate  of  strychnine  of  German 
commerce  has  the  composition  C21H22N2O2H2SO4-I-2H2O,  and  must, 
therefore,  be  considered  an  acid  sulphate,  or,  to  avoid  misunderstand- 
ing, may  be  designated  as  monostrychnine  sulphate,  containing  two 
molecules  of  water  of  crystallization.  The  United  States  Pharmaco- 
poeia recognizes  as  officinal  a  neutral  sulphate,  or  distrychnine  sul- 
phate, (C2iH22N202)2H2S04-l-7H20,  containing  7  molecules  of  water  of 
crystallization.  Salts  of  the  manufacture  of  Messrs.  Rosengarten  & 
Sons,  and  Powers  &  Weightman  were  obtained,  and  will  be  desig- 
nated respectively  as  1  and  2.  The  first  step  taken  was  to  determine 
to  which  class  the  officinal  salt  belongs,  whether  it  consists  of  a 
neutral  or  acid  sulphate  of  strychnine.  This  was  accomplished  by  the 
estimation  of  the  sulphuric  acid  contained  therein.  For  this  determina- 
tion, weighed  portions  of  the  anhydrous  salts  were  dissolved  in  water, 
^  Berichte  der  Deutsch.  Chern.  Ges.,  1881,  p.  1231,  and  Amer.  Journ. 
Pharmacy,  1881,  p,  627. 
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