™'}   A  Soluble  Compound  of  Hydrastine. 
605 
As  is  well  known,  but  few  salts  of  hydrastine  are  readily  soluble 
in  water.  In  our  work  we  made  use  of  monocalcium  phosphate, 
which  was  carefully  purified  by  prolonged  washing  with  alcohol. 
A  saturated  solution  of  the  salt  in  cold  water  was  prepared  by  thor- 
ough trituration,  the  phosphate  being  in  excess.  On  triturating  this 
saturated  solution  with  a  large  excess  of  pure  hydrastine,  a  certain 
amount  of  the  latter  would  enter  into  solution,  time,  as  was  eventu- 
ally found,  being  an  important  factor.  In  order  to  ascertain  the 
nature  of  the  product  obtained,  the  filtered  solution  was  evaporated 
either  by  heat  or  spontaneously,  or  in  a  vacuum.  In  no  case  was  it 
possible  to  detect  any  trace  of  crystallization.  The  solution  invari- 
ably became  syrupy,  and  finally  left  an  amorphous  residue  quite 
similar  to  rosin  in  its  appearance.  This  residue  was  soluble  in 
about  10  parts  of  cold  water.  A  small  amount  of  boiling  water 
would  change  it  into  a  syrup.  Both  boiling  and  cold  alcohol  dis- 
solved it  easily  and  in  about  the  same  proportions.  The  melting 
point  was  I26°-I28°.  Although  there  was  no  criterion  of  the  pur- 
ity of  the  substance,  it  was  submitted  to  analysis.  No  success  fol- 
lowed an  attempt  to  determine  the  amount  of  hydrastine  present  by 
the  use  of  potassium  permanganate,  as  no  definite  end  reaction  could 
be  obtained.  Resort  was  then  had  to  incineration,  care  being  taken 
to  avoid  unnecessarily  high  temperatures  in  the  use  of  platinum 
dishes  for  the  purpose.  The  substance  dried  in  vacuo  was  heated 
to  105  °.  The  very  divergent  results  obtained  showed  that  there 
was  no  fixed  percentage  of  water  held  by  the  compound  after  desic- 
cation in  vacuo.  The  product  of  incineration  was  white,  vitreous 
calcium  metaphosphate.2 
It  was  in  all  cases  calculated  to  monocalcium  orthophosphate,  and 
the  difference  was  assumed  to  be  hydrastine.  Analytical  results 
soon  showed  that  prolonged  trituration  was  necessary  to  increase 
the  amount  of  the  alkaloid  taken  into  combination  by  the  phosphate. 
From  \  \.o  y2  gramme  was  used  in  each  analysis  of  the  substance 
dried  at  105 °.    The  following  analytical  data  were  obtained: 
Time  of 
Trituration. 
10  minutes 
Monocalcium 
Phosphate. 
Hydrastine. 
Per  cent. 
No. 
Per  cent. 
44-69 
38-33 
5570 
I 
55*31 
61-67 
44*30 
2 
15 
5 
3 
2  Birnbaum  :  Jsb.  d.  C/iem.,  1871,  281. 
