260 
Sweetness  of  Dulcin  and  Saccharin. 
5  Am.  Jour.  Pharm. 
(     April,  1921. 
THE  DEGREE  OF  SWEETNESS  OF  DULCIN  1  AND  OF 
SACCHARIN* 
By  Prof.  Dr.  Theodor  Paul. 
Saccharin  is  usually  rated  as  about  450  and  dulcin  250  times 
as  sweet  as  sugar.  By  the  addition  of  dulcin  to  a  solution  of  saccha- 
rin the  increase  in  sweetness  is  much  more  than  that  corresponding 
to  the  additional  sweetness  derived  from  the  added  dulcin.  For 
instance,  the  sweet  taste  of  a  solution  containing  280  mg.  saccharin 
per  liter  is  raised  by  the  addition  of  only  120  mg.  of  dulcin  to  the 
same  degree  as  a  solution  of  535  mg.  of  saccharin  in  a  liter.  The 
sweetness  is  thus  almost  doubled  and  also  a  saving  of  33  per  cent, 
of  sweetener  achieved. 
This  phenomenon  is  explained  by  the  observed  fact  that  the 
"coefficient"  of  sweetness  of  saccharin  and  of  dulcin  is  greater 
in  dilute  solution  than  in  more  concentrated.  For  saccharin  it 
varies  from  200  to  700  (compared  with  210  per  cent,  sugar  solu- 
tions) and  for  dulcin  from  70  to  350.  In  the  instance  cited  above, 
the  degree  of  sweetness  of  280  mg.  saccharin  in  a  liter  corresponds 
to  a  7  per  cent,  sugar  solution  and  that  of  120  mg.  of  dulcin  to  a 
3  per  cent,  sugar  solution.  The  sum  of  the  two  corresponds  fo  a 
.10  per  cent,  sugar  solution,  whereas  to  produce  the  same  degree 
of  sweetness  by  the  use  of  either  saccharin  or  dulcin  alone,  535  mg. 
of  the  former  or  1430  mg.  of  the  latter  is  required. 
The  following  table  shows  the  quantities  of  the  different 
sweeteners  required  to  make  a  solution  possessing  the  same  degree 
of  sweetness,  sugar  (saccharose)  being  taken  as  the  standard  for 
or  of  dulcin,  and  column  4  represents  the  quantities  of  saccharin 
and  of  dulcin  required  to  match  the  sugar  solution  in  column  1. 
comparison.    Columns  2  and  3  represent  the  quantities  of  saccharin 
dulcin,  or  para-phenetole  carbamide,  NH2CO.  NH.C6H4  (O  C2H5), 
forms  colorless  or  slightly  yellow  needles,  soluble  in  about  800  parts  of  cold 
water  and  in  about  50  parts  of  boiling  water.  It  is  obtained  by  the  action 
of  phosgene  on  para-phenetidine  and  treatment  of  the  resulting  chlor  com-' 
pound  with  ammonia. 
*Reprinted  from  Chem.  Zeit,  1921,  No.  4.   Abstracted  by  Joseph  Rosin. 
