280    Chemical  Examination  of  Ipomcea  Purpurea.  {AmJinea9Po8arm* 
fore  extracted  with  ether,  which  removed  all  the  solid  material. 
The  ethereal  liquid,  after  being  shaken  with  a  solution  of  sodium 
carbonate,  was  dried  with  calcium  chloride,  and  the  ether  removed, 
when  a  very  small,  oily  residue  was  obtained,  which  soon  solidified 
in  the  form  of  crystalline  needles.  This  substance  was  practically 
insoluble  in  water,  and  was  therefore  recrystallized  from  ether,  after 
which  it  melted  at  23 3-235 °  C,  but  the  amount  was  much  too  small 
for  further  investigation. 
The  sodium  carbonate  liquid  was  acidified  and  extracted  with 
ether,  when  a  very  small  amount  of  a  substance  was  obtained,  which, 
after  recrystallization  from  50  per  cent,  alcohol  and  finally  from  hot 
water,  separated  in  handsome  needles  melting  at  100-101°  C.  On 
analysis  it  gave  the  following  result  : 
00346  gave  0  0820  C02  and  0-0338  H20.    C  =  64  6  ;  H  =  io-8. 
C14H2804  requires  C  =  64-6;  H  =  10  8  per  cent. 
This  substance  was  evidently  identical  with  ipurolic  acid,  which 
has  previously  been  described. 
The  acid  liquid,  from  which  the  above-mentioned  substances  had 
been  extracted  by  ether,  was  distilled  with  steam.  The  distillate 
contained  a  small  amount  of  acid,  which,  after  conversion  into  a 
barium  salt,  was  found  to  consist  of  a  mixture  of  formic  and  butyric 
acids.  The  liquid  remaining  in  the  distillation  flask  was  treated 
with  baryta  for  the  removal  of  the  sulphuric  acid,  filtered  and  con- 
centrated. A  syrup  was  thus  obtained  which  reduced  Fehling's 
solution  on  heating,  and,  like  the  corresponding  products  from  the 
above-described  ether  and  chloroform  extracts,  contained  the  barium 
salt  of  a  readily  soluble  organic  acid. 
Alcohol  Extract  of  the  Hydrolyzed  Resin. 
This  product  represented  by  far  the  largest  portion  of  the  hydro- 
lyzed resin,  and  amounted  to  130  grammes.  As  first  obtained  it  was 
in  the  form  of  a  syrup,  but,  after  drying,  could  be  reduced  to  a  fine 
powder,  and  by  treatment  with  animal  charcoal  was  obtained  quite 
white.  The  powdered  material  is  not  altered  on  exposure  to  the 
air,  and  dissolves  readily  in  cold  water,  forming  a  clear  solution. 
After  drying  in  a  vacuum  over  sulphuric  acid,  it  melted  at  105-1 10°  C. 
With  cold  concentrated  sulphuric  acid  it  gives  a  deep  red  color. 
It  is  optically  active,  and  its  specific  rotatory  power  was  determined 
with  the  following  result : — 
