Am.  Jour  Pharru. ) 
March,  1885.  J 
Citrate  of  Iron  and  Quinine, 
123 
by  an  additional  sodic  radicle.  In  appearance  it  differs  only  in  having  a 
deeper  shade  of  apple  green.  It  is  equally  soluble,  nondeliquescent, 
and  superbly  scaled.  Its  definite  character  is  shown  that  when  three 
ms.,  or  8*16  grams  of  ferric  citrate,  one  m.,  or  2*10  grams  of  citric 
acid  and  three  ms.,  or  2-52  grams  of  sodium  bicarbonate  are  mixed  in 
the  presence  of  water  heated  until  combined,  and  then  evaporated  and 
dried  at  a  gentle  heat,  a  product  is  obtained  weighing  11 '01  grams. 
From  this  it  appears  that  the  formula  of  the  salt  is  3(FeCi).  NagCi.BAq., 
and  the  molecular  weight  1,101.  It  commends  itself  as  a  substitute 
for  the  now  official  ammonio-ferric  citrate,  over  which  it  has  various 
advantages. 
Owing  to  the  fact  that  in  the  construction  of  the  new  citrate  of  iron 
and  quinium  a  quinium  citrate  would  be  in  some  respects  superior  to 
the  alkaloid  it  became  desirable  to  ascertain  the  composition  of  the 
three  citrates,  containing,  respectively  three,  two  and  one  quinic 
radicles. 
The  first  one  was  therefore  determined  by  uniting  3*78  grams  of 
trihydrous  quinine  and  '70  grams  of  citric  acid  in  contact  with  water, 
then  evaporating  and  drying  it  at  a  gentle  heat  until  the  residue  ceased 
to  lose  weight.  The  product  w^eighed  4' 96  grams,  showing  that  the 
molecular  weight  is  1,488,  and  the  formula  (QuH)3Ci.  18Aq. 
The  second  or  diquinic  citrate  is  obtained  when  3*78  grams  of  tri- 
hydrous quinine  and  1*05  grams  of  citric  acid  are  united  as  in  the  first 
instance.  Tiie  product  weighs  4*65  grams.  This  result  indicates  that 
the  formula  of  the  salt  is  (QuH)2HCi.5Aq,  and  the  molecular  weight 
930.  In  regard  to  appearance  and  solubility  this  salt  closely  similates 
the  triquinic  citrate. 
The  third  was  found  by  a  similar  method  to  give  from  3*78  grams 
of  trihydrous  quinine  and  2*10  grams  of  citric  acid  a  residue  weighing 
5'70  grams.  Its  molecular  weight  is  therefore  570  and  its  formula 
(QuH)H2Ci.3Aq. 
When  3*78  grams  of  quinine  trihydrite  and  1*40  grams  of  citric 
acid  are  combined  as  in  the  three  preceding  cases  the  product  weighs 
5*12  grams.  This  result  shows  that  the  formula  of  the  salt  thus 
obtained  is  (QuH)3El3Ci2.10Aq,  and  that  its  molecular  weight  is  1536. 
It  is  more  crystalline  and  sokible  than  the  first  two  of  the  preceding 
citrates,  and  less  so  than  the  third.  This  compound  is  not  a  mixture, 
but  apparently  a  combination  between  a  monoquinic  citrate  and  a  diqui- 
nic citrate  molecule.    But  it  is  simpler  to  regard  it  as  a  combination 
