Am'May,ri9^8.arm')  Note  on  Euonymus  atropurpureus.  355 
Conclusions. 
The  property  possessed  by  phenolsulphonephthalein,  by  virtue 
of  which  it  is  rapidly  eliminated  by  the  kidney,  is  by  no  means  lim- 
ited to  this  compound.  Several  other  more  or  less  closely  related 
compounds  show  the  same  striking  "  renal  affinity,"  and  might  also 
be  of  value  in  testing  renal  function  were  it  not  that  phenolsulphone- 
phthalein itself  is  so  nearly  ideal  for  this  purpose. 
Compounds  of  the  xanthone  class,  that  is,  phthaleins  (though 
not  necessarily  sulphonephthaleins)  in  which  there  is  an  oxygen 
atom  linking  the  two  phenol  groups,  show  a  similar  remarkable 
"  renal  affinity." 
The  bromination  of  these  compounds,  both  sulphonephthaleins 
and  xanthones,  interferes  with  their  excretion. 
In  view  of  the  hitherto  overlooked  fact  that  numerous  actively 
germicidal  compounds  lose  their  strength  (owing  to  an  as  yet  un- 
explained cause)  when  simply  diluted  with  urine  in  a  test  tube,  the 
value  of  every  drug  used  for  the  purpose  of  urinary  antisepsis  ought 
to  be  questioned  until  its  antiseptic  strength  in  urine  has  been  ex- 
perimentally demonstrated. 
Since  it  has  been  possible  to  establish  a  certain  relationship 
between  chemical  structure  and  renal  excretion,  and  to  predict,  with 
a  reasonable  amount  of  accuracy,  which  drugs  will  and  which  will 
not  be  rapidly  excreted;  since  the  synthesis  of  germicidal  com- 
pounds, very  closely  related  to  the  types  excreted,  has  been  accom- 
plished; and  since  one  of  these  germicidal  compounds  (rhodamin) 
was  excreted  and  would  have  been  successful  but  for  the  interfer- 
ing action  of  the  urine,  the  problem  has  been  shown  to  be  worthy 
of  further  investigation. 
NOTE  ON  EUONYMUS  ATROPURPUREUS.1 
By  E.  M.  Holmes,  F.L.S. 
The  root  bark  of  Euonymus  atropurpureus,  although  discarded 
for  the  U.  S.  P.,  is  still  retained  in  the  B.  P.  Having  recently  had 
occasion  to  compare  a  specimen  of  the  bark,  which  had  been  rejected 
as  not  genuine,  with  the  description  in  the  B.  P.,  I  found  the  de- 
scription given  in  that  work  quite  inadequate  for  recognition  of  the 
1  Reprinted  from  the  Pharmaceutical  Journal  and  Pharmacist,  February 
23,  1918. 
