Am  AJpSI;  Sis!™' }      Constituents  of  Taraxacum  Root.  181 
A  determination  of  its  optical  rotatory  power  gave  the  following 
result : 
0.2046,4  made  up  to  20  c.c.  with  chloroform,  gave  aD  -f-20  30'  in  a 
2-dcm.  tube,  whence  [a]D +122.2  °. 
Monobromioacetyltaraxasterol,  C29H46BrO.CO.CH3. — Half  a 
gram'  of  the  above-described  acetyl  derivative  was  dissolved  in 
chloroform,  and  to  the  cold  solution  a  slight  excess  of  a  solution  of 
bromine  in  the  same  solvent  was  slowly  added.  The  product  was 
crystallised  from  ethyl  acetate,  when  it  separated  in  small,  colorless 
needles,  melting  at  233 — 2340  : 
0.  1204  gave  0.0421  AgBr.    Br.  ==  14.9. 
C31H4902Br  requires  Br  =  15.0  per  cent. 
Benzoyltaraxastcrol,  C29H47O.CO.C6H5. — This  derivative  was 
prepared  by  heating  the  respective  alcohol  for  a  short  time  with 
benzoyl  chloride  and  a  few  drops  of  pyridine.  The  product,  after 
several  crystallisations  from,  a  mixture  of  alcohol  and  chloroform, 
separated  in  glistening  leaflets  melting  at  232 0  : 
0.0810  5  gave  0.2471  CO,  and  0.0728  H20.    C  ==  83.2;  H  ==  10.0. 
C36H5202  requires  C  =  83.7;  H  =  10. 1  per  cent. 
Other  well-crystalised  fractions  obtained  from  the  original 
acetylated  product  above  described  possessed  the  following  char- 
acters : 
1.  M.  p.  216— 2220  ;  [a]D  +68.10  ;  C  =  81.7;  H  =  10.9  per  cent. 
II.  M.  p.  225— 2270 ;  [a]D  +62.20  ;  C  =  81.5  ;  H  —  11.1  " 
III.  M.  p.  225-2350;  [a]D+77-8°;  C=.8i.6;  H  ==  11.3  "  " 
The  composition  and  characters  of  these  fractions  indicated 
them  to  contain  a  substance  analogous  to  taraxasterol,  but  having  a 
lower  melting  point  and  a  lower  optical  rotation.  The  mother- 
liquors  from  these  fractions  were  evaporated,  and  the  residues 
brominated.  By  the  fractional  crystallisation  of  the  product,  a 
further  amount  of  the  above-described  monobromoacetyltaraxa- 
sterol  was  obtained. 
Fractions  of  the  acetylated  product  melting  lower  than  those 
above  mentioned  could  only  be  crystallised  with  difficulty.  The 
4  Dried  at  120°. 
5  Dried  at  t2o°. 
