A Manual of the Chemistry of the Carbon Compounds

TEE CARBON COMPOUNDS, 305
It combines with one molecule of bromine, and with nascent
hydrogen, forming oily hydratopic acid CgU^CH < MQJJ
Isairopio Acid is isomeric isomeric, ot probably polymeric polymeric, with atropio acid,
and formed together with the latter, when tropic acid is heated with
hydrochloric acid to 140°. It is sparingly soluble in boiling water,
and less freely in alcohol than atropic acid, and forms microscopic,
monoclinic crystals, melting only at about 200 s , It does not combine
with nascent hydrogen.
6XYPHENYL-PR0PI0HIC ACID8,
Phtoretie Acid C6H4 -J XT; nn H ' a a P ro duct °^ decomposition of
phloretin (see Olucosides), and crystallizes from boiling water in
brittle, prismatic crystals, melting at 130°, When heated with baryta,
it splits up into carbon dioxide and phlorol (page 382). On fusing it
with potaab, it yields para-oxybenzoic acid.
Hydroparacwmaric Add C0H4 X ^% CO H ^ 1)een ol)ta " ie * ^y
reducing paranitrophenylpropionic acid with tin and hydrochloric
acid, and converting the amido-acid into a diazo-compoiind, which,
when boiled with water, yields oxyphenylpropionic acid. It crystallizes
from water in small, monoclinic prisms, melting at 125", and
yields by oxidation para-oxybenzoic acid.
As both phloretic and hydroparacumaric acid are so easily converted
into para-oxybenzoic acid, they contain the two side-chains in
the position 1*4, and their isoinerism must be caused by the group
U9H4.OH replacing different hydrogen atoms in propionic acid, thus:
C6Ht.0H C,,H,OH
H^C-OH-COjH HaC-CH8-CO2H
f OH
TyroHne, or Ojtyplmiytamidopropionic Add C0H4 -J Q H QTJI \QQ JT
is either a derivative of phloretio acid or of parahydrocumanc acid.
It has not been obtained by synthesis, but is a product of decomposition
of animal substances, such as proteids, hair, feathers, horn, &c,
and exists in old cheese (rvp6