Page:Outlines of Physical Chemistry - 1899.djvu/112

 92 OUTLINES OF PHYSICAL CHEMISTEY

Malic acid :

co 2 h— Ghoh— ch 2 — co 2 h.

The following modifications are known :

1. The Icevo-rotatory acid — obtained from the berries of the mountain ash.

2. The racemic acid (inactive by mixture) — obtained artificially :

(a) by reduction of racemic tartaric acid by hydriodic

acid.

(b) by the action of water on fumaric acid (boiling the

fumaric acid with a dilute solution of caustic soda).

8. The dextro-rotatory acid— obtained:

(a) by reduction of dextro-tartaric acid by hydriodic acid.

(b) by resolving the racemic form. A saturated solution of inactive cinchonine malate is induced to crystallise by sowing with a crystal of the lsevo- malate of the same base. In this way Bremer has, surprising as it may appear, induced a crystallisation of the dextro- malate (' Berichte,' 13, 351, (1880).).

Coniine : C

/ \

I i

H 2 GH — kj$±±i

\ /

N

H

1. Natural coniine is dextro-rotatory.

2. The racemic modification has been synthetically prepared by Ladenburg. a-methylpyridine heated with

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