R = OMe    Quinine
R = H         Cinchonidine

cinchonine

Cinchona Alkaloids

Enantioselective Catalysts

                         .
Cinchona alkaloids  are widely  used  in
the    pharmaceutical    and   chemical
industry.  The  most popular compound
Quinine  is   a    valuable   antimalarial
agent  and  muscle relaxant  compound
for more than 100  years,  its  „pseudo
enantiomer“  Quinidine   is  used as  a
cardiac   depressant   (antiarrhythmic).
Furthermore   Quinine  is  also  an   im-
important bitter agent  in the beverage
(soft drink) industry.

Cinchonine    and    Cinchonidine  are
widespread   resolving   agents   particu-
larly for  acids.  Cinchona  alkaloids  and
their modified  derivatives are significant 
chiral catalysts in asymmetric syntheses
for example Corey enolalkylation & sharp-
less dihydroxylation.


One aspect of their application as ligand
accelerated catalyst  (LAC) is their
bidentate nature which allows
optimal binding to transition
metals.

.


E.J. Corey, J. Am. Chem. Soc.
1997, 119, 12414
enantioselective enolate
alkylation under phase
transfer conditions

[(DHQD)2-PHAL]

K. Barry Sharpless, J. Am Chem. Soc.
1994, 116, 1278
enatioselective osmium-catalyzed
asymmetric dihydroxylation

chinchione  cinchonidine