Am.  Jour.  Pharm. 
Jan.,  1884. 
Theobromine. 
45 
authors,  it  sometimes  contains  4H20  and  sometimes  5H20.  The 
aurochloride  C7H8N402,HAuCl4,  forms  yellow  tufts  of  needles.  The 
sulphate  has  been  obtained  in  small  colorless  crystals,  but  of  varying 
composition.  The  nitrate,  C7H8N402,HN03,  has  been  described  by 
Glasson.  The  acetate,  C7H8N402,C2H402,  forms  a  white  voluminous 
precipitate,  which  gradually  loses  its  acid  by  exposure  to  the  air.  In 
its  behavior  to  methyl  iodide,  theobromine  differs  markedly  from  caf- 
feine, for  on  heating  the  mixture  either  alone  or  in  solution  in  alcohol 
or  in  chloroform,  no  combination  of  the  theobromine  with  the  methyl 
iodide  takes  place,  whilst  if  a  mixture  of  theobromine,  alcoholic  solution 
of  potash,  and  methyl  iodide  in  equivalent  quantities  is  heated  at  100° 
in  sealed  tubes,  caffeine  is  produced,  identical  with  the  natural  bases : 
C7H8N402  +  KOH  +  Mel  =  C7H7MeN402  +  KI  +  H20.  On 
heating  theobromine  with  hydrochloric  acid  at  240 — 250°,  it  suffers 
decomposition  similar  to  that  of  caffeine,  yielding  ammonia,  methyla- 
mine,  sarcosine,  carbonic  anhydride  and  formic  acid.  The  same 
products  are  also  formed  on  boiling  theobromine  with  solution  of 
barium  hydroxide,  and  attempts  to  obtain  an  intermediate  product, 
theobromidine  (corresponding  with  caffeidine)  have  as  yet  been  unsuc- 
cessful. The  bromine  derivative,  C7H7BrN402,  obtained  by  the  direct 
action  of  bromine,  agrees  with  the  compound  described  by  Fischer. 
When  theobromine  is  boiled  with  five  parts  of  concentrated  nitric  acid 
in  an  upright  retort  until  the  greater  part  of  the  liquid  has  been  vola- 
tilized, and  the  residue  then  evaporated  on  a  water-bath,  amalic  acid  is 
obtained.  On  boiling  the  latter  with  concentrated  nitric  acid  a  further 
decomposition  takes  place,  with  evolution  of  carbonic  anhydride  and 
formation  of  methyl  parabanic  acid  and  methylamine.  Maly  and  Hin- 
teregger  (1881,)  have  shown  that,  besides  these  products,  ammonia  is 
also  produced  when  the  oxidation  is  effected  by  means  of  chromic 
mixture.  Caffeine  is  decomposed  by  nitric  acid  in  the  same  way  as 
theobromine,  dimethylparabanic  acid,  methylamine,  and  carbonic  anhy- 
dride being  formed,  and  in  this  case  also  no  ammonia. — Jour.  Chem. 
Soc,  Sept.  1883;  Annalen  217,  p.  287. 
Napelline,  an  amorphous  alkaloid  obtained  from  aconite  root,  has  been 
successfully  used  by  Laborde  to  relieve  neuralgia  pains,  and  as  a  substitute 
for  morphine  in  a  case  of  the  morphine  habit.  It  was  given  hypodermi- 
cally  in  doses  of  from  one  to  four  centigrams  in  the  twenty-four  hours. — 
Journ.  de  Therapeut ;  Louisville  Med.  News. 
