4 
Rhizome  of  Iris  Versicolor. 
f  Am.  Jour.  Pharm. 
I    Jaiuiiuy,  1911. 
water.  These  properties,  together  with  the  resuh  of  its  titration,  as 
given  above,  indicated  it  to  be  Wfphthahc  acid.  In  order  to  con- 
firm its  identity,  a  portion  of  the  substance  was  heated  with  phos- 
phorus pentachloride  in  the  presence  of  benzene,  and  the  product 
vigorously  agitated  with  concentrated  ammonia.  In  this  manner  an 
acid  amide  was  formed,  which  was  collected  and  well  washed  with 
water.  The  latter  compound  sintered  at  260°  and  melted  completely 
at  275°.  A  known  specimen  of  uophthalic  acid,  when  similarly 
treated,  also  yielded  an  acid  amide  sintering  at  260°  and  melting 
at  275°,  and  when  the  two  specimens  of  amide  were  mixed  the  melt- 
ing point  remained  unaltered. 
The  above-described  substance  was  thus  identified  as  z^ophthalic 
acid,  the  occurrence  of  which  in  nature  does  not  appear  to  have  been 
hitherto  observed.  The  amount  of  this  acid  obtained  from  2  kilo- 
grammes of  the  alcoholic  extract  of  "  Blue  Flag  Root  "  was  about 
0.15  gramme,  thus  corresponding  to  0.0019  per  cent,  of  the  weight 
of  the  drug. 
The  phenolic  methyl  esters,  which  had  been  separated  from 
the  non-phenolic  portion  by  means  of  sodium  hydroxide,  as  above 
described,  were  hydrolyzed  by  heating  for  a  short  time  with  an 
aqueous  solution  of  this  alkali.  The  liquid  was  then  acidified,  when 
a  resinous  precipitate  was  deposited,  which  was  extracted  with  ether. 
The  ethereal  liquid  was  washed  and  dried,  and,  on  removing  the 
solvent,  yielded  about  1  gramme  of  a  brown  oil.  Since  the  latter 
did  not  show  any  indication  of  crystallizing,  it  was  agitated  with 
light  petroleum,  the  petroleum  extract  decanted  from  insoluble  oil, 
and  the  solvent  allowed  to  evaporate.  A  trace  of  a  crystalline  solid 
was  thus  obtained,  which  gave  a  violet  coloration  with  ferric  chloride 
as  well  as  the  characteristic  odor  of  oil  of  wintergreen  when  heated 
with  methyl  alcohol  and  a  few  drops  of  concentrated  sulphuric  acid. 
The  presence  of  salicylic  acid  was  thus  indicated,  but  the  amount 
was  too  small  to  admit  of  complete  identification.  That  portion  of 
the  oil  which  was  insoluble  in  light  petroleum  was  again  converted 
into  its  methyl  ester,  and  the  latter  benzoylated  by  the  Schotten-Bau- 
mann  method.  The  product  was  oily,  but  gradually  deposited  a 
few  colorless  crystals.  These  were  separated  from  adhering  oil 
by  spreading  them  on  a  porous  tile,  and  then  recrystallized  from  alco- 
hol, when  they  separated  in  stellar  aggregates  of  fine  needles,  melting 
