Year: 1899

page_text: A communication from LA SOCIÉTÉ CHIMIQUE DES USINES DU RHÔNE, ancienne-
ment Gilliard P., Monnet et Cartier, of Lyons, France, Manufacturers.
I, GEORGE BELOE ELLIS, of the Firm of J. C. Mewburn & Ellis, of 55 and 56,
Chancery Lane, in the County of London, Chartered Patent Agents, do hereby
declare the nature of this invention to be as follows: ;-
This invention relates to the manufacture of new compounds of bismuth,
especially such as are suitable for medicinal purposes.
It is well known that bismuth is particularly prone to form basic salts, such
as the salicylate, tannate, iodide etc., which have hitherto found only limited
pharmaceutical employment.
My correspondents have now discovered that valuable new compounds of bis-
muth may be prepared by the combination of two acid radicles with the bismuth
molecule to form double salts of normal character. Thus the astringent tannic
acid and the antidiarrhoetic lactic acid may be so combined. vielding salts such
as the monolacto-ditannate and the hilacto-monotannate of bismuth, as well as
the corresponding basic compounds. As tannic acid may be used the gallo-tannic
acid, morin tannic acid. catechu-tannic acid kinotannic acid, kolatannic acid,
caffetannic acid, cinchonatannic acid, etc., and according to the molecular propor-
tions used different compounds may be obtained.
In order to carry out the invention the tri-lactate of bismuth or a solution of
bismuth hydroxide in lactic acid may be precipitated with the theoretical quantity
of a tannic acid, or a basic tannate of bismuth treated with lactic acid.
EXAMPLE 1.
Preparation of bismuth bilacto-monotannate. 484 parts crystallised bismuthi
nitrate are converted by the usual "wet" method into bismuth hydroxide. and
the paste obtained introduced into 360 parts of lactic acid of specific gravity 1'21:
on gently warming the mixture the whole of the bismuth hydroxide is gradually
dissolved and trilactate formed. Into this solution a cold solution of 322 parts
gallotannic acid in five times the quantity of water is poured, whereupon the
new compound is precipitated as lacto-tannate. The precipitate is washed with
water or alcohol and dried at a moderate temperature. The compound as thus
obtained is a greenish-yellow powder which is nearly insoluble in water.
EXAMPLE 2.
If in the above example double the quantity of tannin is employed, a bismuth
monolacto-bitannate is obtained which is quite similar in appearance to the above.
If the proportions in Example 1 are adhered to but a larger quantity of water
emplared a hasie bismuth lacto-tannate is formed

page_text: EXAMPLE 3.
154 parts of 40 per cent. basic bismuth monotannate paste prepared and pressed
in the usual way is digested with 100 parts 50 per cent. lactic acid for 12 hours
on a simmering waterbath. To the mixture is then added 2500 parts cold water,
filtered, the precipitate washed with water and dried. Bismuth bilacto-mono-
tannate is thus obtained as a yellow powder. The monolacto-bitannate can be
prepared in a similar manner by taking 238 parts 40 per cent. bismuth bitannate
paste, and proceeding in the same way. This latter method is however not so
advantageous as preparing the double salts from the trilactate.
In place of gallotannic acid the equivalent quantities of other tannic acids,
according to their molecular weights, may be employed in a similar manner.
All the new bismuth double salts are difficult to characterise individually, but
ultimate analysis shows 'their per centage composition to be substantially that
expressed by the above terms of monolacto-bitannate, bilacto-monotannate etc.,
of bismuth. That the new compounds are true double salts and not mere mix-
tures is indicated by the fact that lactic acid, in an excess of which all simple
lactates of bismuth are soluble, does not extract anything from the products
obtained as above.
Dated this 7th day of June 1890
J. C. MEWBURN & ELLIS,
55 and 56, Chancery Lane, London, Chartered Patent Agents.
.:
A communication from. LA SOCIÉTÉ CHIMIQUE DES.USINES DU-RHÔNE, ancienne-
..ment Gilliard P., Monnet et Cartier, of Lyons, France, Manufacturers.
.
I, GEORGE BELOE ELLIS, of the Firm of J. C. Mewburn & Ellis, of 55 and 56,
Chancery Lane, in the County of London, Chartered Patent Agents, do hereby
declare the nature of this invention and in. what manner the same is to be per-
formed to be particularly described and ascertained in and by the following
statement:
-
This invention relates to the manufacture of new compounds of bismuth,
especially such as are suitable for medicinal purposes.
It is well known that bismuth is particularly prone to form basic salts, such
as the salicylate, tannate, iodide etc., which have hitherto found only limited
pharmaceutical employment.
My correspondents have now discovered that valuable new compounds of bis-
muth may be prepared by the combination of two acid radicles with the bismuth
molecule to form double salts of normal character. Thus the astringent tannic
acid and the antidiarrhoetic lactic acid may be so combined, yielding salts such
as the monolacto-ditannate and the bilacto-monotannate of bismuth, as well as
the corresponding basic compounds. As tannic acid may be used the gallo-tannic
acid, morintannic acid, catechu-tannic acid kinotannic acid, kolatannic acid,
caffetannic acid. cinchona tannic acid, gallic acid, etc., and according to the
molecular proportions used different compounds may be obtained.
.
7
In order to carry out the invention the tri-lactate of bismuth or a solution of
bismuth hydroxide in lactic acid may be precipitated with the theoretical quantity
of a tannic acid, or a basic tannate of bismuth treated with lactic acid..

page_text: Preparation of bismuth bilacto-monotannate. 484 parts crystallised bismuth
nitrate are converted by the usual "wet" method into bismuth hydroxide, and
the paste obtained introduced into 360 parts of lactic acid of specific gravity 1'21;
on gently warming the mixture the whole of the bismuth hydroxide is gradually
dissolved and trilactate formed. Into this solution a cold solution of 322 parts
gallotannic acid in five times the quantity of water is poured, whereupon the
new compound is precipitated as lacto-tannate. The precipitate is washed with
water or alcohol and dried at a moderate temperature. The compound as thus
obtained a greenish-yellow powder which is nearly insoluble in water.
EXAMPLE 2.
If in the above example double the quantity of tannin is employed, a bismuth
monolacto-bitannate is obtained which is quite similar in appearance to the above.
If the proportions in Example 1 are adhered to but a larger quantity of water
employed a basic bismuth lacto-tannate is formed.
EXAMPLE 3.
154 parts of 40 per cent. basic bismuth monotannate paste prepared and pressed
in the usual way is digested with 100 parts 50 per cent. lactic acid for 12 hours
on a simmering waterbath. To the mixture is then added 2500 parts cold water.
filtered, the precipitate washed with water and dried. Bismuth bilacto-mono-
tannate is thus obtained as a yellow powder. The monolacto-bitannate can be
prepared in a similar manner by taking 238 parts 40 per cent. bismuth bitannate
paste, and proceeding in the same way. This latter method is however not so
advantageous as preparing the double salts from the trilactate.
EXAMPLE 4.
A more direct modification of Example 1, particularly suitable in the prepara-
tion of the lacto-tannates from gallic acid, and avoiding the separation of the
hydroxide is to dissolve, for example, 285 parts basic bismuth nitrate in 300
parts nitric acid of 36° B., and pour this solution into a mixture of 330 parts
lactic acid, 510 parts soda solution 36° B., and 250 parts water. After thoroughly
mixing, a hot solution of 190 parts crystalline gallic acid in 500 parts water is
added, the precipitate collected, pressed and dried at 45°C. The bilactonono-
tannate produced is a bright yellow powder. By altering the proportions the
monolactobitannate and monolacto-monotannate may be obtained by the same
process.
In place of gallotannic acid the equivalent quantities of other tannic acids,
according to their molecular weights, may be employed in a similar manner.
All the new bismuth double salts are difficult to characterise individually, but
ultimate analysis shows their per centage composition to be substantially that
expressed by the above terms of monolacto-bitannate, bilacto-monotannate etc.,
of bismuth. That the new compounds are true double salts and not mere mix-
tures is indicated by the fact that lactic acid, in an excess of which all simple
lactates of bismuth are soluble, does not extract anything from the products
obtained as above.
Having now particularly described and ascertained the nature of the said
invention, as communicated to me, and in what manner the same is to be per-
formed I declare that what I claim is:-
1. The herein described manufacture of compound salts of bismuth with lactic
acid and tannic acid in molecular proportions substantially as described.
2. The herein described manufacture of compound salts of bismuth with lactic
acid and tannic acid by the addition of tannic acid in. solution to a solution of
the lactate of bismuth substantially as described.

page_text: 3. The herein described manufacture of compound salts of bismuth with lactic
acid and tannic acid by the digestion of the mono- or bi-tannate of bismuth with
lactic acid substantially as described.
4. As new products the compound salts of bismuth with lactic acid and tannic
J. C. MEWBURN & ELLIS,
55 and 56, Chancery Lane, London, W.C., Chartered Patent Agents.