46 
ON  PYROGUAIACINE. 
ON  PYROGUAIACINE. 
By  E.  Ebermayer. 
The  author  has  obtained  a  crystallized  product  by  the  dry  dis- 
tillation of  guaiacum  resin.  A  similar  substance  has  also  been 
described  by  Deville  and  Pelletier,  from  whose  analysis  the  com- 
position of  this  substance  appears  to  be  76-93  carbon,  7*46  hy- 
drogen, and  15«59  oxygen.  It  is  probably  the  same  substance 
obtained  by  Ebermayer,  and  called  by  him  pyroguaiacine.  All 
specimens  of  this  resin  may  not  produce  this  body,  as  Volckel, 
who  has  also  investigated  the  products  of  the  distillation  of  the 
resin,  does  not  mention  it  at  all,  and  the  author  has  obtained 
very  different  quantities  from  different  resins.  In  favorable  cases 
he  obtained  6  grms.  of  the  pure  substance  from  6  lbs.  of  the 
resin ;  it  was  purified  by  filtration  from  the  oily  products,  and 
then  by  crystallization  from  alcohol. 
Pyroguaiacine  has  the  constitution  C14  H7  O2.  It  is  a  neutral 
body,  which  may  be  sublimed  without  change  ;  it  is  colorless,  but 
when  crystallized  from  alcohol  is  of  a  rose  or  yellowish  color  ; 
it  crystallizes  in  small  laminae  or  in  long  needles,  swells  up  in 
potash,  and  is  extracted  again  unchanged  by  alcohol  from  the 
air-dried  potash  compound,  after  the  potash  has  been  saturated 
with  carbonic  acid. 
When  heated  for  a  long  time  with  caustic  ammonia,  pyroguaia- 
cine acquires  a  yellow  color  ;  its  alcoholic  solution,  saturated  with 
ammonia,  leaves  a  yellow  mass  of  nearly  unchanged  pyroguaia- 
cine. When  alcoholic  solutions  of  oxide  of  silver  and  pyroguaia- 
cine are  mixed,  silver  is  reduced. 
Dilute  sulphuric  acid  does  not  act  upon  pyroguaiacine ;  but  if 
the  latter  substance  be  suspended  in  water,  and  concentrated  Sul- 
phuric acid  be  dropped  into  it,  and  the  whole  heated,  it  first  of 
all  becomes  yellow,  then  dissolves  with  a  rose-color,  and  lastly  a 
blue-black  substance  separates.  Concentrated  sulphuric  acid 
becomes  very  strongly  heated  in  contact  with  pyroguaiacine  ; 
the  acid  first  becomes  brown,  then  dingy  green,  and  lastly  deep 
blue,  from  the  separation  of  a  blue-black  body  containing  sulphur. 
Chlorine  gas,  when  passed  through  water  in  which  pyroguaia- 
cine is  suspended,  colors  this  first  yellow,  and  lastly  brown.  The 
final  product  is  a  brittle  readily-pulverizable  mass,  which,  like 
