I. A survey of the known types of synthetic
antimalarial compounds is given and some aspects
of the relation between chemical constitution and
antimalarial activity is discussed.
II. The preparation is described of 5- chloro1:2,2' :3- pyridoacridine derivatives from 8- aminoquinoline or 8- amino- 6- methoxycuinoline on the one
hand and o- chlorobenzoic acid or 2:4- dichlorobenzoic acid on the other. The chlorine atom in
these pyridoacridine compounds has been replaced
by diethylan;inoethylamino and diethylaminomiethylbutylamino side chains.
III. 5- Ghloro- 3:4,2':3'- pyridoacridine and 5 :6-
d' chloro- 3 :4,2' :3'- pyridoacridine have been
synthesized by condensing e- aminoçuinoline with ochlorobenzoic acid and 2:4- dichlorobenzoic acid
respectively. By replacing the chlorine atom
in these two compounds with the appropriate amine,
5- (diethylaminoethylamino) -, 5-(diethylamino-c.-
methyl- butylemino) -, 6- chloro- 5- ¡dicthlaminoethylamino)-, 8- chloro- 5- (diethyla.rrino- c.- metryibutÿlamino) -, and 8- chloro- 5- (diethylanminopropylamino)-
3:4,2':3'- pyridoacridines have been prepered.
IV. None of the derivatives of 1:2,2' :3' -pyridoacridine show any significant activity when tested
on Plasmodium Gallina ccurm in cricks. The four
derivatives of 3:4,2':3' =- pyridoacridine so far tested
are reported as active, the two which contain the
chlorine atom in the 8 position rf the acridine
nucleus having an activity comparable with atebrin