486  Constituents  of  Rhizoma  Podophylli.     {Am  ocZ\I£&rm' 
zene,  and  finally  from  solution  in  hot  45  per  cent,  alcohol.  The 
compound  is  thus  obtained  in  long,  well-formed  prisms.  It  melts 
at  93-95°,  and  at  a  higher  temperature  chars  without  subliming. 
100  cc.  of  water  at  150  dissolves  0-014  gram;  hot  water  dissolves 
somewhat  more.  It  is  very  slightly  soluble  in  ether  and  cold  ben- 
zene, easily  soluble  in  acetone  and  strong  alcohol,  and  with  difficulty 
in  concentrated  acetic  acid.  When  moistened  with  concentrated 
sulphuric  acid  the  crystals  give  an  immediate  cherry-red  coloration, 
which  slowly  passes  through  greenish-blue  tc  violet.  Concentrated 
hydrochloric  and  nitric  acids  produce  a  red  coloration  ;  ferric  chlor- 
ide and  bromine  produce  no  change  ;  the  compound  dissolved  in 
glacial  acetic  acid  gives  a  red  coloration  with  Millon's  reagent.  The 
alcoholic  solution  is  strongly  lsevorotatory.  Zeisel's  method  indi- 
cates the  presence  of  three  methoxyl  groups.  Hydroxyl  does  not 
appeal  5'  o  be  present. 
Podophyllotoxin,  when  oxidized  in  an  alkaline  solution  in  the  cold, 
by  means  of  potassium  permanganate,  yielded,  besides  a  little  carbonic 
anhydride  and  a  brown,  amorphous  substance,  principally  two  com- 
pounds, the  more  considerable  of  which  was podophyllic  acid,  C20H21O9 
obtained  as  well-formed,  colorless  crystals,  from  solution  in  a  mix- 
ture of  benzene  and  alcohol.  The  compound  is  without  action  on 
animals.  It  melts  at  158- 1 6o°.  Its  aqueous  solution,  neutralized 
with  aqueous  potash,  gives  no  precipitate  with  gold,  calcium  or 
barium  chlorides  ;  silver  nitrate  gives  a  white  precipitate,  soluble  in 
much  water ;  copper  acetate  gives  a  blue  precipitate.  The  copper 
salt  (C20H23O9)Cu,  was  prepared  as  beautiful,  light-green  prisms,  and 
analyzed. 
Picropodophyllin  results  from  the  action  of  alkalis  on  podophyllo- 
toxin;  thus,  on  heating  the  latter  with  aqueous  ammonia,  a  well 
crystallized  product  is  obtained,  which  at  first  was  recrystallized  from 
strong  alcohol ;  but  this  was  found  to  be  unnecessary,  as  the  melting 
point,  2270,  was  not  affected  by  it.  Picropodophyllin  has  the  same 
composition  as  podophyllotoxin,  but  they  differ  in  melting  point : 
2270  and  950;  in  their  action  on  polarized  light :  inactive,  lsevorota- 
tory ;  as  to  solubility,  the  former  is  less  soluble  in  all  liquids  than 
the  latter ;  the  latter  gives  Millon's  reaction,  the  former  does  not.  By 
oxidation  and  reduction  the  two  compounds  yield  the  same  products. 
The  residue  of  the  chloroform  extract,  freed  from  crystalline  podo- 
phyllotoxin, yielded  a  little  pier 0 podophyllic  acid  in  crystals  melting 
