Am.  Jour.  Pharm 
February, 
•}     Chemistry  of  Alkaloid  Estimations. 
69 
And  just  as  morphine  combines  with  nitric  acid  to  form  mor 
phine  nitrate,  or,  more  correctly,  as  the  free  base  morphia  reacts 
with  water  to  form  morphium  hydroxide,  and  as  morphium  hydrox- 
ide reacts  with  hydrogen  nitrate  to  form  morphium  nitrate  and 
water,  thus : 
So,  in  the  same  way,  morphine  combines  with  picrolonic  acid  to 
form  morphine  picrolonate,  or,  more  correctly,  morphia  combines 
with  water  to  form  morphium  hydroxide,  and  this  morphium  hydrox- 
ide then  reacts  with  hydrogen  picrolonate  to  form  morphium  picro- 
lonate and  water,  thus : 
C17H1903N  +  HN(C10H7O8N8)O2  =  C17H1903N  .  HN(C10H7O5N3)O2 
A  considerable  number  of  investigations  of  the  composition  of 
the  precipitants  which  alkaloids  form  when  treated  with  this  reagent 
have  been  made.  Especially  have  H.  Mathes  and  O.  Rammstedt  at 
the  University  of  Jena  studied  the  value  of  this  reagent  for  the  valu- 
ation of  vegetable  drugs.  Beyond  the  claim  that  the  composition 
of  these  precipitates  is  constant  and  exceedingly  insoluble,  the 
reagent  is  claimed  to  be  of  special  value  because  of  the  high  melt- 
ing point  of  the  precipitate,  which  melting  point  therefore  may  be 
taken  as  a  proof  of  the  identity  and  the  purity  of  the  alkaloidal 
precipitate. 
Another  reagent,  the  adaptability  of  which  has  been  studied  in 
recent  years,  is  a  solution  of  potassium  bismuth  iodide.  Just  as 
potassium  iodide  forms  a  double  compound  with  bismuth  iodide  so 
alkaloids  react  to  form  the  alkaloid  bismuth  iodides.  And  just  as 
the  compounds  which  potassium  iodide  forms  with  bismuth  iodide 
are  of  a  variable  composition  so  the  alkaloid  bismuth-iodides  are 
variable  and  this  reagent  has  been  used  only  as  a  means  of  separat- 
C17H1903N  +  HNO.  =  C17H1903N.HN03 
morphine ; 
or  C17H1903N  +  H20  =  C17H20O3N .  OH 
C17H30O3N .  OH  +  HN0'3  =  C;7H^OsN.N03  -f  H20 
morphine 
picrolonic  acid ; 
or  C17H1903N  +  H20  =  C17H20O3N  .  OH 
C]7H20O3N  .  OH  +  HN(C10H7O5N3)O2  = 
C17H20O3N  .  N.  (C10H7O.5N3)O2  +  H20. 
