The Manufacture or Production of New Sulpho Acids and Derivatives thereof.
Year: 1893

page_text: Date of Application, 17th May, 1893
Complete Specification Left, 17th Feb., 1894-Accepted, 24th Mar., 1894
PROVISIONAL SPECIFICATION.
[Communicated from abroad by THE FARBENFABRIKEN vormals FRIEDRICH
BAYER & Co., of Elberfeld, in the Empire of Germany.
The Manufacture or Production of New Sulpho Acids and
Derivatives thereof.
I HENRY EDWARD NEWTON of The Office for Patents, 6 Bream's Buildings,
Chancery Lane, in the County of London, Patent Agent, do hereby declare the
nature of this invention to be as follows:-
--
My foreign correspondents have found that gallic acid can be converted into
sulpho derivatives, which advantageously differ from the original product, and that
a like advantageous difference exists between the derivatives, in particular the
salts, of this sulpho acid, and the corresponding derivatives of the original
substance, viz., gallic acid.
The general method of producing these sulpho acids consists either in gradually
stirring dried gallic acid into fuming sulphuric acid, or in first mixing dry gallic acid
with sulphuric acid mono-hydrate, and then gradually introducing fuming sulphuric
acid into the latter mixture, which contains the sulphuric ether of gallic acid formed
during spontaneous heating, and alterable by adding water. In place of fuming
sulphuric acid, sulphuric acid chlorhydrine, sulphurylchloride, or agents producing
the same or a similar effect, can be employed; the gallic acid can be replaced by
the analogous tannin.
In order to illustrate more in detail the method of producing sulpho products of
gallic acid, the following example is given, the parts being by weight.
10 parts of anhydrous gallic acid, dried at 120 degrees centigrade, are gradually
stirred into 50 parts of fuming sulphuric acid (containing 25 per cent. of sulphuric
anhydride), taking care that the temperature does not rise above 30 degrees
centigrade.
The suphurising process may also be carried out as follows:-10 parts of gallic
acid are mixed with 18-75 parts of sulphuric acid monohydrate, and 31.25 parts of
fuming sulphuric acid (containing 40 per cent. of sulphuric anhydride) are then
added to the above mixture.
The sulphuric mixture (resulting from one or other of the aforesaid modes of
treatment) is introduced into 100 parts of ice water, and the diluted sulphuric solution
is allowed to stand for, say, about 24 hours, in order to effect a crystallization.
The sulpho products of gallic acid, chiefly the mono sulpho derivative, then separate
in a very pure state, forming an imperfectly crystallised crust of a palish rose colour.
The purification and separation is effected by crystallising from water, or by
precipitating with acids.
By saturating the sulpho product of gallic acid with hydroxides or carbonates of
metals, the salts of this sulpho acid are obtained.
For instance, a barium salt results on adding carbonate of barium to the watery
solution of the sulpho product of gallic acid, filtering the solution, and precipitating,
from the filtrate, the barium salt, either by the addition of alcohol, or by evaporating
until the crystallization begins.

page_text: Of course, in order to produce the said barium salt, the mixture obtained by
sulphonating gallic acid with sulphuric acid can be directly employed, and the
preparation of the barium salt is then effected by pouring the sulphonation mixture
into ice-water, saturating with carbonate of barium, filtering off the sulphate of
barium and carbonate of barium added in excess, and subsequently isolating the
barium salt in the aforesaid manner.
The thus-formed barium salt of the sulpho derivative of gallic acid, in pure state,
is perfectly white and stable. It is, however, noticeable, that the barium salt, when
containing water, rapidly becomes black, when exposed to the action of the air.
Therefore, it is expedient to exclude the air during the preparation of the barium
salt, and to carry out the operation, for instance, in a current of carbonic acid,
hydrogen, or the like.
My foreign correspondents have found by analytical research, that this barium
salt, when dried at from 150 to 160 degrees centigrade, possesses the following
composition.
PREPARATION OF THE BISMUTH SALT OF THE SULPHO COMPOUND OF
GALLIC ACID.
90 parts of freshly precipitated bismuth hydroxide (BiO₂H) are stirred into a
solution heated to 30 degrees centigrade, and prepared by dissolving 58 parts of the
sulpho product of gallic acid in 2000 parts of water. The resulting mixture is
allowed to stand for some time at 50 degrees centigrade, and finally heated to
boiling. The bismuth salt of gallic sulpho acid thus formed is filtered off and
washed. After drying, it is a yellow, and apparently amorphous powder.
In an analogous manner as the barium and bismuth salt of gallic sulpho acid, the
other salts of this sulpho product can be obtained.
My foreign correspondents have further prepared other derivatives of the said
sulpho acids.
As above mentioned, these sulpho acids; and the derivatives thereof, materially
differ from the gallic acid, and the corresponding derivatives thereof.
My foreign correspondents have, for instance, ascertained, by comparing the
aforesaid gallic sulpho acid having the formula: CH(OH),COOH SO3H, and
the bismuth salt thereof, with the gallic acid, and the bismuth salt derived therefrom,
the following particulars:-
An alkaline solution of gallic sulpho acid is more stable than an alkaline solution
of gallic acid.
Gallic sulpho acid is a much stronger antiseptic than is gallic acid. Whilst
solutions of the former containing one half per cent. of gallic sulpho acid, are
capable of destroying every germ or micro organism, gallic acid is not able to
produce this effect, even when applied in solutions containing one per cent. of
gallic acid.

page_text: The growth of germs or micro organisms is affected by the bismuth salt of
gallic sulpho acid in a higher degree, than by the bismuth salt of gallic acid.
The bismuth salt of gallic sulpho acid, in the presence of alkalies, dissolves much
less readily than the bismuth salt of gallic acid, and therefore the poisonousness of
the former salt (caused by dissolved bismuth) is less than that of the bismuth salt
of gallic acid.
My foreign correspondents have found, in addition to the advantages of gallic
sulphonate of bismuth in comparison with the bismuth salt of gallic acid, that the
former possesses the good properties of the latter salt, for the irritation caused on
the eye of the rabbit by the former salt, apparently is less than that produced by
the bismuth salt of gallic acid. Therefore, there would appear to be no
stimulating action on wounds in the application of the gallic sulphonate of
bismuth.
The sulpho acids derived from gallic acid, and derivatives thereof, are suitable
for being employed in medicine, as the said products possess valuable properties,
in particular as antiseptics, according to the researches of my foreign
correspondents.
.-
1000
NEWTON & SON,
Agents for the Applicant.
COMPLETE SPECIFICATION.
The Manufacture or Production of New Sulpho Acids and
Derivatives thereof.
I, HENRY EDWARD NEWTON of The Office for Patents, 6, Bream's Buildings,
Chancery Lane, in the County of London, Patent Agent, 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 :-
My foreign correspondents have found that gallic acid can be converted into
sulphonic derivatives, which differ advantageously from the original compound, and
that a like advantageous difference exists between the derivatives, in particular the
salts, of this sulphonic acid, and the corresponding derivatives of the original
substance, viz., gallic acid.
The method of producing these sulphonic acids, in general, consists in gradually
stirring either dried gallic acid, or alkaline salts thereof, either into "mono-
hydrated," or into fuming sulphuric acid, subsequently adding fuming sulphuric
acid, if desirable.
In place of fuming sulphuric acid, sulphuric chlorhydrin can be used.
In order to illustrate more in detail the method of producing such sulphonic
derivatives of gallic acid, the following examples are given, the parts being by
maight
"
10 parts of gallic acid are gradually stirred into 50 parts of "monohydrated
sulphuric acid, at from 50 to 55 degrees centigrade, and the resulting mixture is
kept at the said temperature until the gallic acid is perfectly dissolved.
The liquid product is poured onto 50 parts of ice, and the resulting mass is
allowed to stand during about 24 hours, until the sulphonic derivative of gallie
acid has separated in a crystallised form.
The sulphonic compound is then separated by filtration. Or the sulphonated mass
is poured into 500 parts of water, and the resulting solution is used in preparing
salts of the sulphonic derivative of gallic acid.

page_text: 10 parts of anhydrous gallic acid, dried at 120 degrees centigrade, are gradually
stirred into 50 parts of fuming sulphuric acid (containing 25 per cent. of sulphuric
anhydride), taking care that the temperature does not rise above 30 degrees
centigrade.
The sulphonation may also be effected as follows:-10 parts of gallic acid are
mixed with 18-75 parts of "monohydrated" sulphuric acid, and 31.25 parts of
fuming sulphuric acid (containing 40 per cent. of sulphuric anhydride) are then
added to the mixture.
The acid mixture resulting from either of the aforesaid modes of treatment, is
introduced into 100 parts of ice-water, and the diluted solution is allowed to stand
during, say, about 24 hours, in order that any crystallization may take place. The
sulphonic derivatives of gallic acid, chiefly the monosulphonic derivative, then
separate in a very nearly pure state, as an imperfectly crystalline crust of a pure
rose colour. The purification and separation may be effected by recrystallising
from water.
The salts of the sulphonic acid are obtained by saturating the sulphonated
product, for instance, with hydroxides or carbonates of alkalies or metals. Salts
of sulpho gallic acid can also be produced by means of another method generally
known for producing salts, viz., by acting with metallic salts on certain salts of
sulpho gallic acid.
For instance, a barium salt is obtained on adding barium carbonate to the
solution of the sulphonated product, filtering, and precipitating the barium salt
from the filtrate by the addition of alcohol, or by evaporating until crystallization
begins.
The mixture obtained on sulphonating gallic acid with sulphuric acid, can be
directly used in producing the said barium salt, by pouring the sulphonated mixture
into ice-water, saturating with barium carbonate, filtering off the barium sulphate
and barium carbonate added in excess, and subsequently isolating the barium salt
in the aforesaid manner.
My foreign correspondents find that it is expedient to exclude the air during the
preparation of the said barium salt, and to carry out the operation, for instance, in
a current of carbon dioxide, hydrogen, or the like indifferent gas, as the barium
salt rapidly blackens when exposed to the action of the air.
In the pure state, the barium salt, as obtained by excluding air during its
production, is white, and perfectly stable.
My foreign correspondents have found by analysing this barium salt, that it is
represented by the following formula :—
It becomes anhydrous when dried at from 150 to 160 degrees centigrade.
My foreign correspondents have also prepared a potassium salt of sulpho gallic
acid possessing the formula:

page_text: This potassium salt becomes anhydrous when dried at 105 degrees centigrade..
It is formed on dissolving sulpho gallic acid in alcohol, and adding an alcoholic
solution of potash, separating as an amorphous precipitate.
The production of the bismuth salt of sulpho gallic acid is illustrated by the-
following example, the parts being by weight.
\SO3
According to the researches of my foreign correspondents, the same bismuth
gallosulphonate can be obtained by dissolving bismuth hydroxide (BiO₂H) in the
calculated quantity of nitric acid, or by dissolving crystallised bismuth nitrate in
glacial acetic acid, subsequently adding water to either of these solutions, and then
mixing either of them with a hot solution of sodium gallosulphonate.
Other salts of the sulphonated product can be obtained in an analogous manner..
As above mentioned, these sulphonic acids, and the salts thereof, materially
differ from gallic acid and the corresponding salts thereof.
My foreign correspondents have, for instance, ascertained the following par-
ticulars, by comparing the aforesaid sulpho gallic acid of the formula: CH(OH)3.
COOH' SO,H, and the bismuth salt thereof respectively, with gallic acid and the
bismuth salt thereof.
Alkaline solutions of sulpho gallic acid are more stable than alkaline solutions.
of gallic acid.
Sulpho gallic acid is a more powerful antiseptic than is gallic acid, solutions.
containing one half per cent. of sulpho gallic acid being inimical to the growth of
all germs, or micro-organisms, whereas gallic acid is unable to produce this effect,
even when applied in solutions containing one per cent.
The growth of germs or micro-organisms is more affected by the bismuth salt of
sulpho gallic acid than by the bismuth salt of gallic acid.
In the presence of alkalies, the bismuth salt of sulpho gallic acid dissolves much
less readily than the bismuth salt of gallic acid, and, therefore, the poisonousness.
of the former salt, due to the dissolved bismuth, is less than that of the bismuth.
salt of gallic acid.
My foreign correspondents have found, in addition to other advantages afforded
by bismuth gallo sulphonate, in comparison with bismuth gallate, that the former
possesses the good properties of the latter salt, inasmuch as the irritation of the

page_text: eye of the rabbit caused by the former salt, is apparently less than that produced
by the bismuth salt of gallic acid.
Hence it would appear, that no stimulating effect on wounds is produced by the
application of bismuth gallo sulphonate.
The sulphonic acids derived from gallic acid and salts thereof, are suitable for
medicinal use, as, according to the researches of my foreign correspondents, the
said products possess valuable properties, particularly when used as antiseptics.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, as communicated to me
from abroad, I declare that what I claim is :-
1. The production of a sulphonic derivative of gallic acid (sulpho gallic acid)
by the action on gallic acids, or salts thereof, of sulphonating agents.
2. The process for producing salts of sulpho gallic acid, which process consists
in sulphonating gallic acid, or salts thereof, and subsequently converting the sulpho
gallic acid (if desirable, after previously isolating it) into salts, by a suitable
treatment with alkaline or metallic hydroxides or carbonates, or the like.
3. The production of bismuth gallo-sulphonate, either from bismuth hydroxide
and sulpho gallic acid, or from bismuth nitrate, and an alkaline salt of sulpho
gallic acid.
4. As new products of manufacture, the sulpho gallic acid, and salts thereof,
produced by means of the processes herein before defined, or by any other means
affording the same result.
5. The use of sulpho gallic acid and salts thereof, especially bismuth gallo
sulphonate, as antiseptics.
Dated this 14th day of February 1893.
NEWTON & SON,
Agents for the Applicant.