ON  OXYACANTHIN. 
455 
ON  OXYACANTHIN  * 
By  Charles  AVacker. 
The  author  gives  a  condensed  account  of  the  investigations  of 
Gr.  Polex  (Archiv  d.  Ph.  2  R.  vi.  265),  Kemp  (Buchn.  Rep. 
Ixxi.  166),  and  Wittstein  (Praparatenkunde  595),  the  latter 
having  observed  it  in  a  Mexican  species  of  Berberis. 
About  2  3fe.  of  the  precipitate  produced  by  carbonate  of  soda, 
in  the  mother  liquor  of  berberina,  were  treated  with  dilute  hy- 
drochloric acid,  filtered  and  precipitated  bj  ammonia.  The 
precipitate  was  washed  with  water,  dried,  powdered  and  ex- 
hausted with  ether,  which  was  evaporated,  the  extract  left 
behind  was  redissolved  in  dilute  hydrochloric  acid,  and  now 
yielded  with  ammonia  an  almost  white  precipitate.  This  was 
converted  into  the  hydrochlorate,  a  portion  of  which  was  obtained 
in  colorless  crystals,  which  yielded  with  ammonia  a  purely  white 
precipitate.  The  colored  hydrochlorate  was  obtained  colorless 
by  recrystallization. 
The  residues  from  the  treatment  with  ether  was  darker  brown 
than  the  original  precipitate,  and  weighed  only  about  one-eighth 
less  ;  its  taste  was  bitter ;  its  solution  in  acids  yielded  the  same 
precipitate  with  alkalies.  It  appears  to  be  the  alkaloid  com- 
bined with  a  tannic  acid,  the  former  of  which  was  partly  liber- 
ated by  treating  with  carbonate  of  soda  and  exhausting  by 
ether. 
Properties  of  the  alkaloid. — It  is  a  white  powder,  remaining 
unaltered  in  the  shade,  but  turning  yellow  in  the  direct  sunlight, 
the  solution  of  the  latter  in  acids,  yielding  it  whitf  again  on 
supersaturating  with  alkalies.  Under  the  microscope  it  appears 
as  amorphous  globules,  but  crystallizes  from  concentrated  alco- 
holic  and  ethereal  solutions  in  fine  colorless  needles  and  prisms. 
Its  taste  is  purely  bitter,  not  very  persistent.  It  fuses  at  139® 
C.,  is  decomposed  at  a  higher  heat,  and  burns  upon  platinum 
foil  without  leaving  any  residue.    Alcohol  dissolves  much  of  the 
*  Berzelius  proposed  for  this  alkaloid  the  name  berbina,  to  distinguish  it 
from  berberina,  and  indicate  its  occurrence  in  Berberis  vulgaris.  Mr. 
Wacker  now  suggests  the  name  vinetina,  derived  from  vinetier,  the  French 
name  for  barberry. 
