552 
Constitution  of  the  Alkaloids. 
{Am,  Jour.  Pharm. 
Nov.,  1883. 
been  made  synthetically  by  several  chemists,  but  by  expensive  and 
involved  methods,  when  Skraup,  in  1881,  effected  its  synthesis  from 
nitrobenzol  and  glycerin,  or  still  better,  a  mixture  of  nitrobenzol  and 
aniline  with  glycerin.  This  process  allows  of  its  being  made  on  a 
commercial  scale  if  desirable.  Shortly  after,  by  an  application  of  the 
same  principle,  Dobner  and  Miller  effected  the  synthesis  of  lepidine, 
the  second  member  of  the  quinoline  series. 
At  the  same  time  that  this  general  agreement  to  consider  these  bases 
as  the  starting  point  in  the  endeavor  to  effect  the  synthesis  of  the 
natural  alkaloids  had  been  arrived  at  by  chemists,  it  was  thought  well 
to  look  into  the  question  whether  these  bases  and  their  immediate 
derivatives  had  any  therapeutic  value  of  their  own. 
Piperidine,  the  decomposition  product  of  piperine,  which  we  have 
shown  may  be  considered  to  be  hexahydropyridine,  was  examined  by 
Dr.  Kronecker,  of  Berlin,  at  the  request  of  Prof.  Hofmann,  and  was 
found  to  have  an  action  upon  animals  in  many  respects  resembling 
that  of  conine.  Prof.  Filehne,  of  Erlangen,  who  has  studied  a  large 
number  of  these  pyridine  and  quinoline  derivatives,  found,  moreover, 
that  the  hydrochlorate  of  ethyl-piperidine  had  a  physiological  action 
quite  analogous  to  that  of  conine. 
The  physiological  action  of  quinoline  itself  has  been  studied  quite 
extensively  by  Donath  and  others,  and  it  was  found  that  several  of  its 
salts  were  quite  valuable  febrifuges,  acting  very  like  quinine,  and 
capable  in  cases  of  being  used  as  a  substitute  for  it.  In  general,  the 
hydrogen  addition  products  were  found  to  be  more  active  than  the 
simple  base,  an  observation  entirely  in  accord  with  the  theory  formed 
by  Wischnegradsky,  and  by  Konigs,  as  the  result  of  the  study  of  the 
decomposition  products  of  the  alkaloids,  viz.,  the  alkaloids  are  in  gen- 
eral hydrogen  addition  products  of  pyridine  and  quinoline,  or  of  the 
two  bases  combined.  Thus,  Prof.  Filehne  found  that  hydrochlorate 
of  tetrahydroquinoline  was  much  more  energetic  in  its  action  than 
quinoline,  but  could  not  be  used  on  account  of  a  too  powerful  local 
effect.  The  hydrochlorate  of  dimethyl-tetrahydroquinoline,  which  was 
distinguished  by  its  strong  bitter  taste,  much  resembling  that  of  quinine, 
had  an  effect  like  that  of  curare  poison.  The  most  decided  febrifuge 
action,  however,  was  found  by  Prof.  Filehne  to  reside  in  the  hydro- 
chlorate of  oxyhydro-methyl-quinoline,  introduced  to  public  notice  by 
Prof.  O.  Fischer  uuder  the  name  of  "  Kairin,"  and  in  the  acid  sulphate 
of  tetrahydro-methylquinoline,  introduced  under  the  name  of  Kairo- 
