Am  Jour.  Pharir.  » 
Dec,  1880.  / 
The  Alkaloids  of  Dtta  Bark. 
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cipitable  from  solutions  of  its  salts  by  ammonia,  which  they  named 
ditamine,"  and  another  substance  presenting  much  similarity  to  the 
alkaloids,  inasmuch  as  it  formed  a  compound  with  oxalic  acid,  but  dif- 
fering in  that  it  did  not  pass  into  ether  and  similar  solvents  when  treated 
with  an  excess  of  ammonia.  Other  attempts  made  to  isolate  this  sub- 
stance were  unsuccessful,  and  the  naming  of  it  was  deferred  until  further 
experiment  should  disclose  its  nature. 
Meanwhile,  dita  bark,  as  appears  from  a  later  paper  by  Harnack 
("Archiv  f.  exp.  Path.  u.  Pharmakologie,"  viii,  p.  126),  was  worked 
upon  by  E.  Merck,  who  succeeded  in  preparing  from  it  a  crystallizable 
base,  which,  in  1876,  he  showed  at  the  Exhibition  of  Scientific  Appa- 
ratus, at  South  Kensington.  Harnack  examined  this  substance,  which 
Merck  considered  to  be  pure  ditamine,^  and  found  that  in  the  supposed 
ditamine  there  was  present  the  hydrochlorate  of  an  active  vegetable 
base,  which,  having  obtained  from  ether  in  crystals,  he  named  "crys- 
tallized ditaine."  Harnack  further  came  to  the  opinion,  like  Merck, 
that  dita  bark  contained  no  basic  substance  besides  this  alkaloid. 
Hereupon,  in  a  paper  entitled  "Historische  Notiz  iiber  Ditain," 
Husemann  (''Archiv  f.  Pharmacie,"  ccxii,  p.  438)  declared  that  ditaine 
had  long  before  been  prepared  by  Scharlee,  and  named  "alstonine." 
This  led  the  author  of  the  present  paper  (Hesse)  to  make  some  remarks 
upon  the  subject  Berichte,"  xi,  p.  1547),  and  as  Harnack's  investi- 
gation was  then  unknown  to  him,  and  Husemann  in  his  paper  had 
treated  Grippe's  and  Harnack's  ^'ditains"  as  identical,  he  thought 
Harnack's  investigation  had  been  carried  out  with  dita  extract.  This 
error  induced  Harnack  to  publish  an  extract  from  his  paper  in  the 
"Journal  of  the  German  Chemical  Society,"  xi,  2004,  in  which  he 
stated  that  dita  bark  contained  only  one  alkaloid,  namely,  "crystallized 
ditain,"  and  he  considered,  therefore,  that  Hesse's  communication,, 
according  to  which  dita  bark  contained  two  alkaloids,  ditamine  and 
echitamine,  was  due  to  imperfect  observation. 
In  the  pfesent  paper,  therefore,  Hesse  describes  exhaustively  these 
two  alkaloids,  together  with  a  third,  " echitenine.^'  The  last-named 
has  been  known  to  him  some  time,  but  a  communication  respecting  it 
has  been  delayed  until  it  was  ascertained  whether  this  alkaloid  was 
actually  contained  in  the  bark,  or  was  first  formed  during  the  prepara- 
tion of  the  other  two. 
1  Merck  at  first  designated  this  substance  "dittamine,"  but  appears  subsequently  to 
have  chosoi  for  it  the  name  of  "  ditaine." 
