Improvements in the Treatment of Piporazine.
Year: 1896

page_text: Date of Application, 19th No. 1890
Complete Specification Loft 13th Aug 1897-Accented 19th Nov. 1897
Date of Application, 19th Nov., 1890
Complete Specification Left 13th Aug 1897-Accented 19th Nov.
PRO
IONAL SPECI
TION.
Improvements in the Treatment of Piporazine.
We, WALTER BEACALL BISHOP, Chemical Manufacturer, of 48 Spelman Street,
Milend New Town, in the County of London, and FRANCIS WILLIAM PASSMORE
of 63 Queen Victoria Street in the City of London, Research Chemist, do hereby
declare the nature of this invention to be as follows:-
This invention relates to the conversion of piperazine into non-hygroscopic and
stuble salts which may facilitate the technical employment and the accuracy of
dosage of piporazine in medicinal and pharmaceutical preparations.
It is well known that piperazine base forms with water a number of crystalline
compounds or hydrates containing various quantities of water of crystallisation
according to the conditions of crystallisation. Moreover the base and its hydrates
are of a very hygroscopic and deliquescent nature and absorb moisture and
carbonic acid from the air and cannot be dried even at a low temperature without
loss from volatilisation, all of which properties render the technical employment
of piperazine and its accurate dosage in the compounding of medicinal and phar-
maceutical compounds extremely difficult.
According to our invention we have discovered that all these difficulties may
be overcome by the preparation of solid combinations or salts of piperazine with
citric or tartaric acids. These salts are constant in composition, non-hygroscopic.
and may be dried at a temperature considerably above the boiling point of water
without melting or loss from volatilisation.
In order to prepare these salts we dissolve the piperazine in as little boiling
water as possible and add the citric acid or tartaric acid either in powder form or as
hot concentrated aqueous solution. Or the piperazine and acid, both in the solid
state, may be melted together. For preference we employ two molecular pro-
portions of citric acid to three molecular proportions of piperazine base or hydrate,
or one molecular proportion of tartaric acid to one molecular proportion of pipora-
zine base or hydrate, or we add the acid to the solution of piperazine until it is
neutral in reaction to litmus paper, but we do not confine ourselves to any of the
above proportions as we find that combinations equally suitable for some purposes
may be made with other proportions.
The salts are allowed to crystallise slowly (if desired recrystallised) and dried.
Dated this 17th day of November, 1896.
WALTER BEACALL BISHOP.
F. W. PASSMORE.

page_text: Improvements in the Treatment of Piperazine.
We, WALTER BEACALL BISHOr, Chemical Manufacturer, of 48 Spelman Street,
Mile End New Town, in the County of London, and FRANCIS WILLIAM PASSMORE
of 63 Queen Victoria Street in the City of London, Research Chemist, 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 conversion of piperazine into non-hygroscopic and
stable salts which may facilitate the technical employment and the accuracy of
dosage of piperazine in medicinal and pharmaceutical preparations.
It is well known that piperazine base forms with water a number of crystalline
compounds or hydrates containing various quantities of water of orystallisation
according to the conditions of crystallisation. Moreover the base and its hydrates
are of a very hygroscopic and deliquescent nature and absorb moisture and
carbonic acid from the air and cannot be dried even at a low temperature without
loss from volatilisation, all of which properties render the technical employment
of piperazine and its accurate dosage in the compounding of medicinal and phar-
maceutical compounds extremely difficult.
According to our invention we have discovered that all these difficulties may
be overcome by the preparation of solid combinations or salts of piperazine with
citric or tartaric acids. These salts are constant in composition, non-hygroscopic,
and may be dried at a temperature considerably above the boiling point of water
without melting or loss from volatilisation.
In order to prepare these sults we dissolve the piporazine in as little boiling
water as possible, and add the citric or tartaric acid either in powder form or as
hot-concentrated aqueous solution. Or the piperazine and acid both in the solid
state may be molted together. We employ two molecular proportions of citric
acid to three molecular proportions of piperazine base or hydrate, or one molecular
proportion of tartaric acid to one molecular proportion of piperazine base or
hydrate, or we add the acid to the solution of piperazine until it is noutral in
reaction to litmus paper.
The salts are allowed to crystallise slowly (if desired, re-crystallised) from their
aqueous solutions, or may be precipitated from the aqueous solution with alcohol
or alcohol and ether and dried.
The before mentioned salts can be used in cases where the base is now usually
presoribed; but its particular application is in combination with other pharma-
ceutical products where the base is not applicable on account of its unstable
nature. The non-hygroscopic salts before mentioned can be advantageously used
to form or assist in forming a new offervescent which will make an effervescing
medicinal draught or beverage in a way well understood by chomists.
Having now particularly described and ascertained the nature of our said a
invention and in what manner the same is to be performed, we declare that what
we claim is:-
1. The manufacture of non-hygroscopic stable neutral salts of piperazine by
treating piperazine with citric or tartaric acid, substantially as described.
2. As novel products the dry neutral citrates and tartrates of piperazine having 4
the characteristic properties above specified.
3. In the manufacture of dry effervescent preparations the use of piperazine

page_text: citrates or tartrates in the dry neutral form substantially as and for the purposes
above described.
Dated this 13th day of August 1897.
J. C. MEWBURN & ELLIS,
55 and 56 Chancery Lane, London, Chartered Patent Agents.