Year: 1897

page_text: We, Dr. LUDWIG LANDSHOFF Chemist and Dr. PAUL MEYER, Chemist trading as
the Chemische Fabrik Grünau Landshoff and Meyer of Grünau near Berlin, in the
Empire of Germany, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement :-
The process forming the subject matter of the present invention has for its object
the production of tribenzoylgallic acid which is distinguished by the possession of
striking therapeutical properties. It does not become decomposed either by
protracted exposure to the air or by treatment with cold, lukewarm or boiling
water.
Neither is a protracted treatment with pepsinhydrochloric acid, or with pepsin or
hydrochloric acid alone, in the cold or in the heat, able to split up the same into
benzoic acid and gallic acid. Even the saliva of the mouth has practically no effect.
But an intense and complete decomposition with liberation of gallic acid is produced
when it is mixed with the glycerine extract of the pancreas gland. From this and
also from the setting up of a gallic acid reaction in urine after internal use of the
substance, it follows that a decomposition must take place in the bowel. The product
thus shows all those extremely valuable properties which are required of an agent for
producing astringency of the bowel and urine passages.
None of the agents heretofore known and employed for the same purpose has
fulfilled those requirements to an equal extent. They are mostly all very slightly
defined, they have mostly a great tendency to become decomposed, and above all in
consequence of their want of permanency or stability, they act prejudically upon the
alimentary canals and the stomach.
Furthermore the product according to this invention possesses all the characteristics,
such as form of crystals, and melting point, which enable it to be easily and with
certainty identified at any time, and also allow of its purity being tested.
The process is as follows;-18.8 kilos. of gallic acid are shaken up with 50 litres of
water, 100 kilos. of ice, and a solution 22.5 kilos. of caustic potash, in about 50 litres
of water, the air being excluded as much as possible. As soon as solution has taken
place, the shaking is continued whilst slowly adding 42.5 kilos. of benzoyl-chloride to
the solution. After a short time, the crude tribenzoyl compound is precipitated
When the odour of
partly in the form of flakes, and partly in small lumps.
benzoylchloride has disappeared the reaction being then completed, the product thus
produced is extracted with boiling water for the purpose of removing soluble
impurities such as gallic acid and benzoic acid. The residue has added to it some
animal charcoal and is recovered once or twice by re-crystallization from alcohol.
this way there are obtained small white sparkling crystals which melt at 186° and
have the composition of tribenzoylgallic acid.
In

page_text: H 3.73 %
3.96 %
4.01 %
The new compound is insoluble in water, rather well soluble in hot alcohol, less
soluble in cold, little-soluble in hot benzol; it is colourless, inodorous, insipid.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is-
Process for the production of tribenzoylgallic acid characterized by the fact that an
alkaline solution of gallic acid is shaken up with benzoylchloride and the product
thus produced is purified by crystallization after being boiled up with water.
Dated this 22nd day of April 1897.
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and
18, Temple Street, Birmingham,
Agents.