Note: Descriptions are shown in the official language in which they were submitted.
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Organic salts of Q-Alanine
Field of the Invention
The present invention relates to a structure and method for producing
stable salts of fl-alanine and organic acids. More specifically, formed salts
of the
present invention are particularly well suited for oral administration thereby
the
formed salts may provide enhanced nutritional andlor therapeutical efficacy in
relation to the individual components alone.
Background of the Invention
It is commonly known that increased muscle mass, strength and extended
muscular performance occur in the most effective manner when exercise
routines are done to complete exhaustion. However, during extended periods of
exercise, metabolites from the breakdown of adenosine triphosphate (ATP),
mainly hydrogen ions (H+), begin to accumulate leading to a decline in the pH
levels of blood and muscle, which can be problematic or undesirable. The
increase in acidity of the muscle, as a result of the accumulation of H+ ions,
is
directly linked to muscle fatigue, which ultimately causes a decrease in the
duration of intensive bouts of exercise (Cooke R, Pate E. The effects of ADP
and
phosphate on the contraction of muscle fibers. Biophys J. 1985 Nov;48(5):789-
98). This fatigue is a result of inhibition of enzymes, by decreased pH, which
are
vital for energy production and the force-producing capacity of muscles
(Febbraio
MA, Dancey J. Skeletal muscle energy metabolism during prolonged, fatiguing
exercise. J Appl Physiol. 1999 Dec;87(6):2341-7).
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Carnosine is one of the most effective buffers, or pH stabilizers, in human
skeletal muscle, and as such is very efficient at mopping up excess H+ ions.
25 When carnosine is ingested as food, it must be broken down to its
constituent
amino acids (.8-aianine and histidine) in order cross cell membranes, after
which
it is then reassembled. Due to lack of absorption, in addition to the
financial cost
of the raw material, carnosine, administration of the constituent amino acids
has
been explored. For example, administration of exogenous 8-alanine has been
30 shown to increase the levels of carnosine in skeletal muscle cells (Bate-
Smith
EC. The buffering of muscle in rigour: protein, phosphate, and carnosine. J
Physiol. 1938;92:336-43).
Additionally, other methods for increasing the duration of exercise have
been explored. One such method is the administering of compounds that are
35 essential for ATP synthesis and are depleted during exhaustive exercise,
such as
malic acid. Malic acid is a naturally occurring compound found in a large
number
of fruits and vegetables, as well as all living cells; which plays a key role
in the
transportation of NADH from the cytosol to the mitochondria for energy
production (ATP production). Malic acid is part of the initiation of the Krebs
cycle
40 and is one of the only metabolites that actually decrease in concentration
during
exercise. Thus, administration of exogenous malic acid will result in
increased
ATP production as a result of attenuation of malic acid depletion.
Supplementation with other deprotonated organic acids can be used for
attenuation of metabolic acidosis. For example, citrate lacks all of its
acidic
45 protons, yielding three carboxylate functionalities that can readily take
up free
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protons. Since all of acidic protons are removed, the citrate has three sites
which
are capable of taking up free protons in serum and working muscle. Therefore,
administration of deprotonated organic acids can inhibit the decrease in pH,
which is a result of ATP hydrolysis, thereby leading to less fatigue resulting
from
50 the inhibition of enzymes that are vital for energy production and the
force-
producing capacity of muscles.
Summary of the Invention
In the present invention, compounds and methods for their production are
disclosed. Specifically, the compounds are salts comprising an organic acid
and
55 Q-alanine, and having a structure of Formula.1:
Formula 1
0
NH3 0 ~ AO
~OH
wherein:
A" represents a deprotonated organic acid selected from the group
60 consisting of: malate, citrate and fumarate; and
where A- is malate or fumarate, n = 2, and
where A- is citrate; n = 3.
Detailed Description of the Invention
In the following description, for the purposes of explanations, numerous
65 specific details are set forth in order to provide a thorough understanding
of the
present invention. It will be apparent, however, to one of ordinary skill in
the art
that the present invention may be practiced without these specific details.
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The present invention is directed towards the structures and synthesis of
salts of a-alanine and organic acids.
70 The present invention provides for the production of stable salts, which
may afford a combination of,B-alanine and an organic acid, free of
physiologically
unsafe additives to an individual upon administration to said individual.
Furthermore, the present invention is particularly well suited for use in
tablets,
capsules, powders, granules, powdered beverage mixes and other forms known
75 in the art of dietary supplements.
,8-alanine combined with an organic acid forms a non-hygroscopic
crystalline powder, which is stable in storage and can be processed without
special precautions. Due to the non-hygroscopic nature of the /3-alanine salt
it
would be understood by one of skill in the art, that the salt is easy to
process and
80 is particularly suitable for processing with rapidly running machines,
since it does
not tend to stick together or become lumpy.
As used herein, '/3-alanine' refers to the chemical beta-alanine, also known
as 3-aminopropionic acid. Additionally, as used herein, ',8-aianine' also
includes
derivatives of fl-alanine such as esters, amides, and salts, as well as other
85 derivatives, including derivatives having pharmacoproperties upon
metabolism to
an active form.
As used herein, 'malic acid' refers to the chemical 1-Hydroxy-1,2-
ethanedicarboxylic acid, (CAS Registry No. 6915-15-17), also known as,
hydroxybutanedioic acid, hydroxysuccinic acid, malate, or 2-
90 hydroxybutanedioate. Additionally, as used herein, 'malic acid' also
includes
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derivatives of malate such as esters, amides, and salts, as well as other
derivatives, including derivatives having pharmacoproperties upon metabolism
to
an active form.
As used herein, 'citric acid' refers to the chemical 2-hydroxy-1,2,3-
95 propane-tricarboxylic acid, (CAS Registry No. 77-92-9), also known as, ,6-
hydroxytricarboxylic acid . Additionally, as used herein, 'citric acid' also
includes
derivatives of citrate such as esters, amides, and salts, as well as other
derivatives, including derivatives having pharmacoproperties upon metabolism
to
an active form.
100 As used herein, 'fumaric acid' refers to the chemical (E)-2-butenedioic
acid, (CAS Registry No. 110-17-8), also known as, trans-1,2-
ethylenedicarboxylic
acid, allomaleic acid, and boletic acid. Additionally, as used herein,
'fumaric acid'
also includes derivatives of fumarate such as esters, amides, and salts, as
well
as other derivatives, including derivatives having pharmacoproperties upon
105 metabolism to an active form.
As used herein, the term 'organic acid' refers to organic compounds which
contain carboxylic acids (-C(O)OH). Typical examples of organic acids include,
but are not limited to; malic acid, fumaric acid, citric acid, orotic acid,
lactic acid,
pyruvic acid, and tartaric acid.
110 As used herein, the term 'pharmaceutically acceptable excipients' refers
to
substances added to produce quality tablets, chewable tablets, capsules,
granulates or powders, but which do not provide nutritive value. A non-
exhaustive list of examples of excipients includes monoglycerides, magnesium
CA 02610821 2007-12-12
stearate, modified food starch, gelatin, microcrystalline cellulose, glycerin,
stearic
115 acid, silica, yellow beeswax, lecithin, hydroxypropyicel lu lose,
croscarmellose
sodium, and crosprovidone.
According to the present invention, the compounds disclosed herein
comprise molecules of Q-alanine combined with an organic acid to form a salt
having a structure according to Formula 1. The aforementioned compound being
120 prepared according to the reaction as set forth for the purposes of the
description
in Scheme 1:
Scheme 1
1) Heat
~ AO
NH2 0 2) Cool (RT to 4 C) NH3 0
'-~A+ HA ~
OH Lower Alcohol OH n
1 2 3
With reference to Scheme 1, in the first step of the reaction the fl-alanine
125 (1) is dissolved in an excess of hot lower alcohol. The lower alcohol is
considered to be hot, as would be known by one of ordinary skill in the art.
Preferably the lower alcohol is considered to be hot when heated to a
temperature about 5 C below the boiling point of the corresponding lower
alcohol.
130 In various embodiments of the present invention, the lower alcohol is
selected from the group consisting of methanol, ethanol, propanol, and
isopropanol. These lower alcohols may be used singly or in admixture
containing
two or more alcohols.
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Concurrently, in the second step of the reaction the organic acid (2) is
135 dissolved into an excess of hot lower alcohol. The lower alcohol is
considered to
be hot, as would be known by one of ordinary skill in the art. Preferably the
lower
alcohol is considered to be hot when heated to a temperature about 5 C below
the boiling point of the corresponding lower alcohol.
Both solutions above are then mixed together and heated to about the
140 boiling point of the corresponding lower alcohol. If there are solids
still present
after heating, the solution is filtered while hot to remove any unreacted
starting
materials. The solution is then allowed to cool to room temperature, covered
and
refrigerated or cooled until crystallization occurs, preferably for between
about 24
to about 48 hours. The resultant crystals are filtered under vacuum and washed
145 with ice cold lower alcohol, yielding a crystalline powder, the a-alanine
organic
acid salt (3).
In larger scale preparations of the present invention, diethyl ether can be
added until the cloud point, as would be known to one of skill in the art, is
reached after the mixture is cooled to room temperature, after which the
solution
150 is refrigerated or cooled to allow crystallization to complete. This will
facilitate
greater precipitation of the product thus yielding more of the a-alanine
organic
acid salt (3), which would be desired in industrial settings.
,Q-alanine organic acid salts are used advantageously alone or with
additional active ingredients, such as, trace elements, vitamins, mineral
155 substances, or other amino acids as well as, optionally, excipients
usually used
for the preparation of the respective forms of administration. The forms of
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administration include, particularly, all varieties of tablets, both those
that are
swallowed without being chewed, and tablets to be chewed or dissolved in the
mouth of an individual, as well as those that are dissolved in a liquid before
being
160 ingested by an individual. The tablet forms include uncoated tablets, one-
layer or
multilayer or encased forms or effervescent tablets. Further preferred forms
of
administration are capsules of hard and soft gelatin, the latter being
particularly
suitable to include a liquid core. Additionally, 8-alanine organic acid salts
can be
used advantageously for the preparation of solutions and suspensions and as a
165 powder, either effervescent or granulated.
The examples given below explain the execution of the invention with
respect to the production of /3-alanine organic acid salts. Provided below is
a
basic method for producing fl-alanine organic acid salts. However, those of
skill
in the art will appreciate certain changes may be made in the process of
"scaling-
170 up" the reaction to manufacture larger batches of B-alanine organic acid
salts
which may be required for commercial uses and supply requirements. Other
methods of synthesis may also be apparent to those of skill in the art.
175
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Examples
Example 1
1) Heat
NH2 0 HO O OH 2) Cool (RT to 4 C) NH3 O O 0 ~
+ ~ 0
(,-OH -~ EtOH
OH O OH 2 OH 0
1 2 3
178.18 g (2 mol) of fl-alanine (1) is dissolved into 400mL of hot ethanol,
180 solution 1. Concurrently, 134.09 g (1 mol) of malic acid (2) is dissolved
in 200mL
of hot ethanol, solution 2. Solution 2 is added to solution I with stirring
and the
resultant solution is heated to the boiling point. If there are solids still
present the
solution is filtered at this temperature to remove unreacted starting
materials.
The solution is then allowed to cool to room temperature and then covered and
185 refrigerated to allow crystallization to complete; about 24 hours. The
resultant
crystals are filtered under vacuum and washed with ice cold ethanol, yielding
a
crystalline powder, the,8-alanine malate (3).
Example 2
1) Heat
NH2 0 + 0/ OH 2) Cool (RT to 4 C) NH3 O = 0I/ O
~OH HO~ ~~ O
0 Propanol OH 2 O
190 1 2 3
178.18 g (2 mol) of ,r33-alanine (1) is dissolved into 400mL of hot propanol,
solution 1. Concurrently, 116.07 g (1 mol) of fumaric acid (2) is dissolved in
200mL of hot propanol, solution 2. Solution 2 is added to solution I with
stirring
and the resultant solution is heated to the boiling point. If there are solids
still
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195 present the solution is filtered at this temperature to remove unreacted
starting
materials. The solution is then allowed to cool to room temperature and
refrigerated to allow crystallization to complete; about 24 hours. The
resultant
crystals are filtered under vacuum and washed with ice cold ethanol, yielding
a
crystalline powder, the fl-alanine fumarate (3).
200
Example 3
0 0
1) Heat
NH2 0 HO OH 2) Cool (RT to 4 C) NH3 [ OH]3[!HO]
- OH + sHO
OO
2 3
267.27 g (3 mol) of a-alanine (1) is dissolved into 600mL of hot
isopropanol, solution 1. Concurrently, 192.12 g (1 moI) of citric acid (2) is
205 dissolved in 300mL of hot isopropanol, solution 2. Solution 2 is added to
solution
I with stirring and the resultant solution is heated to the boiling point. If
there are
solids still present the solution is filtered at this temperature to remove
unreacted
starting materials. The solution is then allowed to cool to room temperature
and
refrigerated to allow crystallization to complete; about 24 hours. The
resultant
210 crystals are filtered under vacuum and washed with ice cold ethanol,
yielding a
crystalline powder, the,8-alanine citrate (3).
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Extensions and Alternatives
215 In the foregoing specification, the invention has been described with a
specific embodiment thereof; however, it will be evident that various
modifications and changes may be made thereto without departing from the
broader spirit and scope of the invention.
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