U.S. patent application number 12/027033 was filed with the patent office on 2008-07-10 for n-substituted (benzoimidazol-2-yl)phenylamines, processes for their preparation, their use as a medicament or diagnostic aid, and a medicament comprising them.
This patent application is currently assigned to SANOFI-AVENTIS DEUTSCHLAND GMBH. Invention is credited to Uwe HEINELT, Armin HOFMEISTER, Martin HUG, Hans-Jochen LANG, Klaus WIRTH.
Application Number | 20080167359 12/027033 |
Document ID | / |
Family ID | 34228991 |
Filed Date | 2008-07-10 |
United States Patent
Application |
20080167359 |
Kind Code |
A1 |
HEINELT; Uwe ; et
al. |
July 10, 2008 |
N-Substituted (Benzoimidazol-2-yl)phenylamines, Processes for Their
Preparation, Their Use as a Medicament or Diagnostic Aid, and a
Medicament Comprising Them
Abstract
This invention is directed to the compound of formula (I),
compositions containing said compounds to inhibit the sodium-proton
exchanger of subtype 3 (NHE3) which are useful in the prevention or
treatment of various disorders in a patient suffering from a
disease state, such as, renal disorders including acute or chronic
renal failure, disorders of biliary function and for respiratory
disorders such as snoring or sleep apnea or for stroke.
Inventors: |
HEINELT; Uwe; (Weisbaden,
DE) ; LANG; Hans-Jochen; (Hofheim, DE) ;
HOFMEISTER; Armin; (Oppenheim, DE) ; WIRTH;
Klaus; (Kriftel, DE) ; HUG; Martin; (Freiburg,
DE) |
Correspondence
Address: |
ANDREA Q. RYAN;SANOFI-AVENTIS U.S. LLC
1041 ROUTE 202-206, MAIL CODE: D303A
BRIDGEWATER
NJ
08807
US
|
Assignee: |
SANOFI-AVENTIS DEUTSCHLAND
GMBH
Frankfurt
DE
|
Family ID: |
34228991 |
Appl. No.: |
12/027033 |
Filed: |
February 6, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10770654 |
Feb 3, 2004 |
|
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12027033 |
|
|
|
|
60477569 |
Jun 11, 2003 |
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Current U.S.
Class: |
514/395 ;
548/307.4 |
Current CPC
Class: |
A61P 9/12 20180101; A61P
9/00 20180101; A61P 13/12 20180101; A61P 1/16 20180101; A61P 3/00
20180101; A61P 25/18 20180101; A61P 25/00 20180101; A61P 9/10
20180101; A61P 25/08 20180101; A61P 25/22 20180101; C07D 235/30
20130101; A61P 33/02 20180101; A61P 1/00 20180101; A61P 11/00
20180101; A61P 33/06 20180101; A61P 7/02 20180101; A61P 33/00
20180101; A61P 25/24 20180101 |
Class at
Publication: |
514/395 ;
548/307.4 |
International
Class: |
A61K 31/4184 20060101
A61K031/4184; C07D 235/04 20060101 C07D235/04; A61P 11/00 20060101
A61P011/00; A61P 13/12 20060101 A61P013/12; A61P 9/00 20060101
A61P009/00; A61P 25/00 20060101 A61P025/00; A61P 3/00 20060101
A61P003/00; A61P 33/00 20060101 A61P033/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 4, 2003 |
DE |
10304294.6 |
Claims
1. A compound of formula I ##STR00013## wherein, R1 and R4 are
independently selected from the group consisting of H, F, Cl, Br,
C.sub.1-C.sub.4-alkyl and C.sub.1-C.sub.4-alkoxy wherein, the
C.sub.1-C.sub.4-alkyl and C.sub.1-C.sub.4-alkoxy are optionally
substituted independently of one another by 1, 2, 3, 4, 5, 6, 7, 8
or 9 fluorine atoms; R2 and R3 are independently selected from the
group consisting of H, F, OH, C.sub.1-C.sub.3-alkyl, and
C.sub.1-C.sub.3-alkoxy wherein, the C.sub.1-C.sub.3-alkyl and
C.sub.1-C.sub.3-alkoxy are optionally substituted independently of
one another by 1, 2, 3, 4, 5, 6 or 7 fluorine atoms; R5 is
independently selected from the group consisting of
C.sub.1-C.sub.4-alkyl, C.sub.2-C.sub.4-alkenyl and
C.sub.3-C.sub.5-cycloalkyl, wherein, the C.sub.1-C.sub.4-alkyl,
C.sub.2-C.sub.4-alkenyl and C.sub.3-C.sub.5-cycloalkyl are
optionally substituted by 1, 2, 3, 4, 5, 6, 7, 8 or 9 fluorine
atoms; and R6 and R7 are independently selected from the group
consisting of H, F, Cl, Br, C.sub.1-C.sub.4-alkyl and
C.sub.1-C.sub.3-alkoxy, wherein, the C.sub.1-C.sub.4-alkyl and
C.sub.1-C.sub.3-alkoxy are optionally substituted independently of
one another by 1, 2, 3, 4, 5, 6, 7, 8 or 9 fluorine atoms, provided
that R6 and R7 are not simultaneously hydrogen; or the
pharmaceutically acceptable salt, or trifluoroacetic acid salt
thereof.
2. The compound according to claim 1 wherein, R1 and R4 are
independently selected from the group consisting of H, F, Cl, Br,
C.sub.1-C.sub.4-alkyl and C.sub.1-C.sub.4-alkoxy, wherein, the
C.sub.1-C.sub.4-alkyl and C.sub.1-C.sub.4-alkoxy are optionally
substituted independently of one another by 1, 2, 3, 4, 5, 6, 7, 8
or 9 fluorine atoms; R2 and R3 are independently selected from the
group consisting of H, F, OH, C.sub.1-C.sub.3-alkyl, or
C.sub.1-C.sub.3-alkoxy, wherein, the C.sub.1-C.sub.3-alkyl and
C.sub.1-C.sub.3-alkoxy are optionally substituted independently of
one another by 1, 2, 3, 4, 5, 6 or 7 fluorine atoms; R5 is
independently selected from C.sub.1-C.sub.4-alkyl,
C.sub.2-C.sub.4-alkenyl and C.sub.3-C.sub.5-cycloalkyl wherein, the
C.sub.1-C.sub.4-alkyl, C.sub.2-C.sub.4-alkenyl and
C.sub.3-C.sub.5-cycloalkyl are optionally substituted by 1, 2, 3,
4, 5, 6, 7, 8 or 9 fluorine atoms; and R6 and R7 are independently
selected from the group consisting of F, Cl, Br,
C.sub.1-C.sub.3-alkyl or C.sub.1-C.sub.3-alkoxy, wherein, the
C.sub.1-C.sub.3-alkyl and C.sub.1-C.sub.3-alkoxy are optionally
substituted independently of one another by 1, 2, 3, 4, 5, 6 or 7
fluorine atoms, provided that R6 or R7 does not correspond to
hydrogen.
3. The compound according to claim 1, which is:
(1H-benzoimidazol-2-yl)(2,6-dichlorophenyl)methylamine;
(1H-benzoimidazol-2-yl)(2,6-dichlorophenyl)ethylamine;
(2,6-dichlorophenyl)(5-fluoro-1H-benzoimidazol-2-yl)methylamine;
(1H-benzoimidazol-2-yl)(2,6-dichlorophenyl)isopropylamine;
allyl(1H-benzoimidazol-2-yl)(2,6-dichlorophenyl)amine;
(1H-benzoimidazol-2-yl)cyclopentyl(2,6-dichlorophenyl)amine; or the
pharmaceutically acceptable salt, or trifluoroacetic acid salt
thereof.
4. A method of inhibiting the activity of sodium-proton exchanger
of subtype 3 (NH3) comprising contacting an inhibitory amount of a
pharmaceutically effective amount of a compound according to claim
1 to a patient in need thereof.
5. A method of treatment or prophylaxis with a pharmaceutical
composition comprising a compound of formula I and/or a
pharmaceutically acceptable salt thereof, of claim 1, for a
disorder of the respiratory drive, a respiratory disorder, a
sleep-related respiratory disorder, sleep apnea, snoring, an acute
renal disorder, a chronic renal disorder, an acute renal failure, a
chronic renal failure, a disorder of an intestinal function, a
disorder of high blood pressure, a disorder of essential
hypertension, a disorder of the central nervous system, a disorder
resulting from central nervous system overexcitability, epilepsy
and centrally induced convulsions, a disorder of an anxiety state,
depressions and psychoses, an ischemic state of the peripheral and
central nervous system, a stroke, a disorder of acute and chronic
damage to a peripheral organ and limb caused by an ischemic event,
a disorder of a peripheral organ and limb caused by a reperfusion
event, a disorder of atherosclerosis, a disorder of lipid
metabolism, a disorder of thromboses, a disorder of biliary
function, a disorder of infestation by ectoparasites, a disorder
resulting from endothelial dysfunction, a protozoal disorder,
malaria, for the preservation and storage of a transplant for a
surgical procedure, for use in a surgical operation and an organ
transplant, for the treatment of shock, for the treatment of
diabetes and late damage from diabetes, for the treatment of a
disease in which cellular proliferation represents a primary or
secondary cause, and for maintaining health and prolonging
life.
6. The method of claim 5 wherein, the compound or salt is used in
combination with one or more other drugs or active ingredients.
7. The method of claim 5 wherein, the drug is for the treatment or
prophylaxis of a disorder of the respiratory drive and/or of a
sleep-related respiratory disorder.
8. The method of claim 7 wherein, the sleep-related respiratory
disorder is sleep apnea.
9. The method of claim 5 wherein, the drug is for the treatment or
prophylaxis of snoring.
10. The method of claim 5 wherein, the drug is for the treatment or
prophylaxis of an acute renal disorder, a chronic renal disorder,
an acute renal failure, or a chronic renal failure.
11. The method of claim 5 wherein, the drug is for the treatment or
prophylaxis of a disorder of an intestinal function.
12. A pharmaceutical composition for human, veterinary or
phytoprotective use comprising a pharmaceutically effective amount
of one or more compounds or a salt according to claim 1.
13. The composition of claim 12 further comprising one or more
other pharmacologically active ingredients or drugs.
Description
[0001] This application claims the benefit of U.S. Provisional
Application No. 60/477,569, filed Jun. 11, 2003. The content of
U.S. Provisional Application 60/477,569 is incorporated herein by
reference.
FIELD OF THE INVENTION
[0002] The invention relates to compounds of the type of
N-substituted (benzoimidazol-2-yl)phenylamines which inhibit the
sodium-proton exchanger of subtype 3 (NHE3) and which are useful in
the prevention or treatment of various disorders. Thus, the
compounds can be employed, inter alia, for renal disorders such as
acute or chronic renal failure, for disorders of biliary function,
for respiratory disorders such as snoring, sleep apneas or for
stroke.
SUMMARY OF THE INVENTION
[0003] The invention relates to compounds of the formula I
##STR00001##
in which the meanings are: [0004] R1 and R4 [0005] independently of
one another H, F, Cl, Br, alkyl having 1, 2, 3 or 4 carbon atoms or
alkoxy having 1, 2, 3 or 4 carbon atoms, [0006] where the alkyl and
alkoxy groups are unsubstituted or are substituted independently of
one another by 1, 2, 3, 4, 5, 6, 7, 8 or 9 F atoms; [0007] R2 and
R3 [0008] independently of one another H, F, alkyl having 1, 2, or
3 carbon atoms, alkoxy having 1, 2 or 3 carbon atoms or OH, [0009]
where the alkyl and alkoxy groups are unsubstituted or are
substituted independently of one another by 1, 2, 3, 4, 5, 6 or 7 F
atoms; [0010] R5 [0011] alkyl having 1, 2, 3 or 4 carbon atoms,
alkenyl having 2, 3 or 4 carbon atoms or cycloalkyl having 3, 4 or
5 carbon atoms, [0012] where the alkyl, alkenyl and cycloalkyl
groups are unsubstituted or are substituted by 1, 2,3,4,5,6,7,8 or9
F atoms; [0013] R6 and R7 [0014] independently of one another H, F,
Cl, Br, alkyl having 1, 2 or 3 carbon atoms or alkoxy having 1, 2
or 3 carbon atoms, [0015] where the alkyl and alkoxy groups are
unsubstituted or are substituted independently of one another by 1,
2, 3, 4, 5, 6, 7, 8 or 9 F atoms, [0016] and at least one of the
two radicals R6 or R7 does not correspond to hydrogen; [0017] and
the pharmaceutically acceptable salts and trifluoroacetic acid
salts thereof.
[0018] Preference is given to compounds of the formula I in which
the meanings are: [0019] R1 and R4 [0020] independently of one
another H, F, Cl, Br, alkyl having 1, 2, 3 or 4 carbon atoms or
alkoxy having 1, 2, 3 or 4 carbon atoms, [0021] where the alkyl and
alkoxy groups are unsubstituted or are substituted independently of
one another by 1, 2, 3, 4, 5, 6, 7, 8 or 9 F atoms; [0022] R2 and
R3 [0023] independently of one another H, F, alkyl having 1, 2 or 3
carbon atoms, alkoxy having 1, 2 or 3 carbon atoms or OH, [0024]
where the alkyl and alkoxy groups are unsubstituted or are
substituted independently of one another by 1, 2, 3, 4, 5, 6 or 7 F
atoms; [0025] R5 [0026] alkyl having 1, 2, 3 or 4 carbon atoms,
alkenyl having 2, 3 or 4 carbon atoms or cycloalkyl having 3, 4 or
5 carbon atoms, [0027] where the alkyl, alkenyl and cycloalkyl
groups are unsubstituted or are substituted by 1, 2, 3, 4, 5, 6, 7,
8 or 9 F atoms; [0028] R6 and R7 [0029] independently of one
another F, Cl, Br, alkyl having 1, 2 or 3 carbon atoms or alkoxy
having 1, 2 or 3 carbon atoms, [0030] where the alkyl and alkoxy
groups are unsubstituted or are substituted independently of one
another by 1, 2, 3, 4, 5, 6 or 7 F atoms; [0031] and at least one
of the two radicals R6 or R7 does not correspond to hydrogen;
[0032] and the pharmaceutically acceptable salts and
trifluoroacetic acid salts thereof.
[0033] Compounds of the formula I preferred in one embodiment are
those in which R1 and R4 are described independently of one another
by H or F.
[0034] Compounds of the formula I preferred in a further embodiment
are those in which R2 and R3 are described independently of one
another by H or F.
[0035] Compounds of the formula I preferred in a further embodiment
are those in which R5 is described by methyl, ethyl, isopropyl,
allyl or cyclopentyl.
[0036] Compounds of the formula I preferred in a further embodiment
are those in which R6 and R7 are described independently of one
another by F, Cl, Br or methyl, and compounds in which R6 and R7
are described by Cl are particularly preferred.
[0037] Compounds of the formula I preferred in a further embodiment
are those in which R6 and R7 are not described by hydrogen.
[0038] The following compounds of the formula I are very
particularly preferred: [0039]
(1H-benzoimidazol-2-yl)(2,6-dichlorophenyl)methylamine, [0040]
(1H-benzoimidazol-2-yl)(2,6-dichlorophenyl)ethylamine,
(2,6-dichlorophenyl)(5-fluoro-1H-benzoimidazol-2-yl)methylamine,
[0041] (1H-benzoimidazol-2-yl)(2,6-dichlorophenyl)isopropylamine
allyl(1H-benzoimidazol-2-yl)(2,6-dichlorophenyl)amine, or [0042]
(1H-benzoimidazol-2-yl)cyclopentyl(2,6-dichlorophenyl)amine and the
pharmaceutically acceptable salts and trifluoroacetic acid salts
thereof.
[0043] If the substituents R1, R2, R3, R4, R5, R6 or R7 contain one
or more centers of asymmetry, they may independently of one another
have both the S and the R configuration. The compounds may be in
the form of optical isomers, of diastereomers, of racemates or of
mixtures thereof in all ratios.
[0044] The present invention includes all tautomeric forms of the
compounds of the formula I.
DETAILED DESCRIPTION OF THE INVENTION
[0045] Definition of Terms
[0046] As used above, and throughout the description of the
invention, the following terms, unless otherwise indicated, shall
be understood to have the following meanings.
[0047] "Patient" includes both human and other mammals.
[0048] "Pharmaceutically effective amount" is meant to describe an
amount of a compound, composition, medicament or other active
ingredient effective in producing the desired therapeutic
effect.
[0049] "Optionally substituted" means either unsubstituted or
substituted one or more times by substituents, which may be the
same, or different.
[0050] Alkyl radicals may be straight-chain or branched. This also
applies when they have substituents or occur as substituents of
other radicals, for example in fluoroalkyl radicals or alkoxy
radicals. Examples of alkyl radicals are methyl, ethyl, n-propyl,
isopropyl (=1-methylethyl), n-butyl, isobutyl (=2-methylpropyl),
sec-butyl (=1-methylpropyl), tert-butyl (=1,1-dimethylethyl).
Preferred alkyl radicals are methyl, ethyl, isopropyl. One or more,
for example 1, 2, 3, 4, 5, 6, 7, 8 or 9, hydrogen atoms in alkyl
radicals may be replaced by fluorine atoms. Examples of such
fluoroalkyl radicals are trifluoromethyl, 2,2,2-trifluoroethyl,
pentafluoroethyl, heptafluoroisopropyl. Substituted alkyl radicals
may be substituted in any positions.
[0051] Alkenyl radicals may be straight-chain or branched. This
also applies when they have substituents, for example in
fluoroalkenyl radicals. The alkenyl radicals may be unsaturated in
various positions and also polyunsaturated. Examples of alkenyl
radicals are ethenyl, n-prop-1-enyl, n-prop-2-enyl, isoprop-1-enyl
(=1-methylethenyl), n-but-1-enyl, n-but-2-enyl, n-but-3-enyl,
n-but-1,3-dienyl, isobut-1-enyl (=2-methylprop-1-enyl),
isobut-2-enyl, (=2-methylprop-2-enyl), sec-but-1-enyl
(=1-methylprop-1-enyl). Preferred alkenyl radicals are ethenyl,
n-prop-1-enyl, n-prop-2-enyl, n-but-1-enyl, n-but-2-enyl. One or
more, for example 1, 2, 3, 4, 5, 6 or 7, hydrogen atoms in alkenyl
radicals may be replaced by fluorine atoms. Substituted alkenyl
radicals may be substituted in any positions.
[0052] Examples of cycloalkyl radicals are cyclopropyl, cyclobutyl,
cyclopentyl. One or more, for example 1, 2, 3, 4, 5, 6, 7, 8 or 9
hydrogen atoms in cycloalkyl radicals may be replaced by fluorine
atoms.
[0053] Methods for preparing the compounds of the formula I are
also described. Thus, the compounds described by formula I can
prepared in a manner known to the skilled worker from N-substituted
cyanamides of the formula II and the appropriate
ortho-phenylenediamines of the formula III, which are obtainable in
large numbers by purchase or easily accessible by synthesis.
##STR00002##
[0054] N-Substituted cyanamides of the formula II can be obtained
by reacting the corresponding cyanamides IV with the compounds of
R5-X. In this case, X is a group which can be replaced
nucleophilically--such a chlorine, bromine, iodine, alkylsulfonate
or arylsulfonate.
##STR00003##
[0055] The required cyanamides IV can be prepared by various
methods known from the literature (Chem. Ber. 1908, 41, 524, J.
Med. Chem., 1975, 18, 90-99, Org. Lett. 2000,795).
[0056] Alternatively, compounds of the formula I can also be
prepared from N-substituted anilines of the formula V and
benzoimidazole derivatives of the formula VI in a manner known from
the literature.
##STR00004##
[0057] In this case, Y is a group that can be replaced
nucleophilically, such as, for example, chlorine, bromine, iodine,
alkylsulfonate such as, methanesulfonate or
trifluoromethanesulfonate or arylsulphonate such as tosylate
(analogous to Arch. Pharm. 1997, 330 (12) 372).
[0058] A further possibility is also to obtain the compounds of the
formula I by reacting the 2-anilinobenzoimidazoles of the formula
VII with compounds R5-X, where X is defined as described above.
Compounds of the formula VII can be prepared by methods known from
the literature (WO 02 46169, Synthesis 1983, 861).
##STR00005##
[0059] A further access to compounds of the formula I is provided
by a synthetic sequence which starts from 2-nitrophenyl
isothiocyanates of the formula VIII (J. Med. Chem. 1985, 28, 1925).
The latter are reacted with amines of the formula V to give
thioureas of the formula IX, which, after reduction, preferably
with hydrogen in the presence of palladium/carbon or platinum
dioxide or tin(IV) chloride and hydrochloric acid, provide the
amino thioureas X, which are then cyclyzed to the compounds of the
formula I, preferably in the presence of methyl iodide (Mel) or
dicyclohexylcarbodiimide (DCCI), which may also be bound to a solid
phase.
##STR00006##
[0060] All substituents R1 to R7 mentioned in the synthetic
processes have the meaning as defined for compounds of the formula
I.
[0061] It was surprisingly possible to show in the present
invention that the described compounds are potent inhibitors of the
sodium/hydrogen exchanger (NHE), in particular of NHE3.
[0062] Known NHE3 inhibitors are derived, for example, from
compounds of the acylguanidine type (EP 825 178), norbornylamine
type (DE 199 60 204), 2-guanidinoquinazoline type (WO 01 79 186, WO
02 20496) or benzamidine type (WO 01 21582, WO 01 72 742).
Squalamine, which is likewise described as an NHE3 inhibitor (M.
Donowitz et al., Am. J. Physiol. 276 (Cell Physiol. 45: C136-C144),
does not act immediately like the compounds of formula I, but
reaches its maximum strength of effect only after one hour.
[0063] German patent application DE10163239 proposes NHE3
inhibitors of the imidazolidine type. NHE3 inhibitors of the
2-phenylaminobenzoimidazole type have recently been disclosed (WO
02 46169).
[0064] Alkylations on the aniline nitrogen position in compounds of
this type have, however, not previously been described.
[0065] German patent application DE 10224892 describes NHE3
inhibitors of the thiophene type. Japanese patent JP2869561
describes substituted benzoimidazoles for inhibiting platelet
adhesion.
[0066] It has now been found, surprisingly, that alkylations of the
aniline nitrogen do not lead to loss of the NHE3 activity. The
hydrogen atom on the aniline nitrogen therefore appears not be
essential for the NHE3 activity. Compared with the
2-phenylaminobenzoimidazoles described above, the compounds
described herein are distinguished by greater lipophilicity,
whereby the brain/plasma ratio is improved, which is particularly
important for central indications.
[0067] Clonidine, which is similar to the compounds described
herein, is known as a weak NHE inhibitor. Its effect on the rat
NHE3 is indeed extremely moderate, with an IC.sub.50 of 620 .mu.M.
Instead, it shows a certain selectivity for NHE2, for which it has
an IC.sub.50 of 42 .mu.M (J. Orlowski et al J. Biol. Chem. 268,
25536). It should therefore rather be referred to as an NHE2
inhibitor. Besides the weak NHE effect, clonidine has a high
affinity for the adrenergic alpha2 receptor and imidazoline I1
receptor, mediating a strong blood pressure-lowering effect
(Emsberger et al, Eur. J. Pharmacol. 134, 1, 1987).
[0068] Compounds of the formula I are distinguished by an increased
NHE3 activity.
[0069] NHE3 is found in the body of various species preferentially
in the bile, the intestine and the kidney (Larry Fliegel et al,
Biochem. Cell. Biol. 76: 735-741, 1998), but has also been detected
in the brain (E. Ma et al. Neuroscience 79: 591-603).
[0070] On the basis of their unexpected NHE-inhibitory properties,
the compounds of the formula I are suitable for the prevention and
treatment of diseases caused by an activation or by an activated
NHE. The use of the compounds of the invention relates to the
prevention and treatment of acute and chronic diseases in
veterinary and human medicine.
[0071] Thus, NHE inhibitors of the invention are suitable for the
treatment of diseases caused by ischemia and/or by reperfusion.
[0072] The compounds described herein are, as a result of their
pharmacological properties, outstandingly suitable as
antiarrhythmic drugs with a cardioprotective component for
prophylaxis of infarction and for treatment of infarction, and for
the treatment of angina pectoris, in which connection they also
inhibit or greatly reduce in a preventive manner the
pathophysiological processes associated with the development of
ischemia-induced damage, in particular in the induction of
ischemia-induced cardiac arrhythmias. Because of their protective
effects against pathological hypoxic and ischemic situations, the
compounds of the formula I which are used according to the
invention can, as a result of inhibition of the cellular
Na.sup.+/H.sup.+ exchange mechanism, be used as drugs for the
treatment of all acute or chronic damage induced by ischemia or
disorders induced primarily or secondarily thereby. This relates to
the use thereof as drugs for surgical interventions, e.g. in organ
transplantations, in which cases the compounds can be used both to
protect the organs in the donor before and during removal, to
protect removed organs for example on treatment with or storage
thereof in physiological bath fluids, as well as during the
transfer into the recipient organism. The compounds are likewise
valuable drugs with a protective action during the performance of
angioplastic surgical interventions, for example on the heart as
well as peripheral vessels.
[0073] In accordance with their protective action against
ischemia-induced damage, the compounds are also suitable as drugs
for the treatment of ischemias of the nervous system, especially of
the CNS, in which connection they are suitable for example for the
treatment of stroke or of cerebral edema.
[0074] In addition, the compounds of the formula I which are used
according to the invention are likewise suitable for the treatment
of types of shock, such as, for example, of allergic, cardiogenic,
hypovolemic and bacterial shock.
[0075] In addition, the compounds induce an improvement in the
respiratory drive and are therefore used to treat respiratory
conditions associated with the following clinical conditions and
diseases: disturbance of central respiratory drive (e.g. central
sleep apneas, sudden infant death, postoperative hypoxia),
muscle-related breathing disorders, breathing disorders after
long-term ventilation, breathing disorders associated with altitude
adaptation, obstructive and mixed type of sleep apneas, acute and
chronic pulmonary disorders with hypoxia and hypercapnia.
[0076] The compounds additionally increase the tone of the muscles
of the upper airways, so that snoring is suppressed.
[0077] A combination of an NHE inhibitor with a carbonic anhydrase
inhibitor (e.g. acetazolamide), the latter inducing metabolic
acidosis and thus itself increasing respiratory activity, proves to
be advantageous due to an enhanced effect and reduced use of active
ingredient.
[0078] The compounds described herein are additionally suitable as
drugs for the therapy and prophylaxis of disorders and impairment
induced by overexcitability of the central nervous system,
especially for the treatment of epileptiform disorders, centrally
induced clonic and tonic spasms, states of mental depression,
anxiety disorders and psychoses. The NHE inhibitors described
herein may moreover be used alone or in combination with other
substances having antiepileptic activity or antipsychotic active
ingredients, or carbonic anhydratase inhibitors, for example with
acetazolamide, and with other inhibitors of NHE or of the
sodium-dependent chloride-bicarbonate exchanger (NCBE).
[0079] It has emerged that the compounds used according to the
invention have a mild laxative effect and accordingly can be used
advantageously as laxatives or if there is a risk of
constipation.
[0080] The compounds of the invention can additionally be used
advantageously for the prevention and therapy of acute and chronic
disorders of the intestinal tract caused by ischemic states in the
intestinal region and/or by subsequent reperfusion. Such
complications may be induced for example by inadequate bowel
peristalsis, like those for example to be observed frequently after
surgical interventions, associated with constipation or greatly
reduced bowel activity.
[0081] It is additionally possible to prevent gallstone
formation.
[0082] The compounds of the formula I used according to the
invention are furthermore distinguished by a strong inhibitory
effect on the proliferation of cells, for example of fibroblast
cell proliferation and the proliferation of smooth vascular muscle
cells. The compounds of the formula I are therefore suitable as
valuable therapeutic agents for diseases in which cell
proliferation represents a primary or secondary cause, and can
therefore be used as antiatherosclerotic agents, agents to prevent
late complications of diabetes, agents to prevent chronic renal
failure, cancers, fibrotic disorders of the heart and also
pulmonary fibrosis, hepatic fibrosis or renal fibrosis, organ
hypertrophies and hyperplasias, for example of the heart and
prostate and can thus be utilized for the prevention and treatment
of (congestive) heart failure or for prostate hyperplasia or
prostate hypertrophy.
[0083] The compounds of the invention are effective inhibitors of
the cellular sodium-proton antiporter (Na/H exchanger) which is
elevated in numerous disorders (essential hypertension,
atherosclerosis, diabetes, etc.), also in those cells which are
readily amenable to measurements, such as, for example, in
erythrocytes, platelets or leukocytes. The compounds used according
to the invention are therefore suitable as excellent and simple
scientific tools, for example in their use as diagnostic aids for
determining and distinguishing different types of hypertension, but
also of atherosclerosis, of diabetes and late complications of
diabetes, proliferative disorders etc.
[0084] The compounds of the formula I are moreover suitable for
preventive therapy to prevent the development and for the treatment
of high blood pressure, for example of essential hypertension,
because they reduce or completely inhibit the reabsorption of NaCl
in the tubular system of the kidneys. Accordingly, they are also
outstandingly suitable as combination and formulation partners for
drugs used for treating high blood pressure. Examples of possible
combinations are diuretics having a thiazide-like action, loop
diuretics, aldosterone and pseudoaldosterone antagonists, such as
hydrochlorothiazide, indapamide, polythiazide, furosemide,
piretanide, torasemide, bumetanide, amiloride, triamterene. The NHE
inhibitors of the present invention can further be used in
combination with ACE inhibitors such as, for example, ramipril,
enalapril or captopril. Further beneficial combination partners are
also .beta.-blockers.
[0085] The described NHE inhibitors can likewise be used in the
prevention and for the treatment of thrombotic disorders because,
as NHE inhibitors, they are able to inhibit both platelet
aggregation itself and, in addition, are able to inhibit or prevent
the excessive release of coagulation mediators, in particular of
von Willebrand factor. The NHE inhibitors of the present invention
can therefore be combined with further anticoagulant active
ingredients such as, for example, acetylsalicylic acid, thrombin
antagonists, factor Xa antagonists, drugs with fibrinolytic
activity, factor VIIa antagonists etc. Combined use of the present
NHE inhibitors with NCBE inhibitors is particularly beneficial.
[0086] It has additionally been found that NHE inhibitors show a
beneficial effect on serum lipoproteins. It is generally
acknowledged that blood lipid levels which are too high, so-called
hyperlipoproteinemias, represent a considerable risk factor for the
development of arteriosclerotic vascular lesions, especially
coronary heart disease. The reduction of elevated serum
lipoproteins therefore has exceptional importance for the
prophylaxis and regression of atherosclerotic lesions. The
compounds used according to the invention can therefore be used for
the prophylaxis and regression of atherosclerotic lesions by
eliminating a causal risk factor. The NHE inhibitors of the
invention can also be combined in a beneficial manner with other
antiarteriosclerotic active ingredients such as a substance from
the class of fibrates, an upregulator of LD2 receptor activity such
as MD-700 and LY295427 or a cholesterol or bile acid absorption
inhibitor or an antihypercholesterolemic agent from the class of
statins, such as, for example, pravastatin, lovastatin,
simvastatin.
[0087] With this protection of the vessels against the syndrome of
endothelial dysfunction, compounds of the formula I are valuable
drugs for the prevention and treatment of coronary vasospasms,
peripheral vascular diseases such as intermittent claudication, of
atherogenesis and of atherosclerosis, of left-ventricular
hypertrophy and of dilated cardiomyopathy, and thrombotic
disorders.
[0088] Said compounds can likewise be used for the treatment of
diseases caused by protozoa and are particularly suitable as
antimalarials.
[0089] The compounds are additionally suitable for controlling
sucking parasites such as mosquitoes, ticks, fleas and plant
pests.
[0090] In accordance with their protective effects, the compounds
are also suitable as drugs for maintaining health and prolonging
life.
[0091] The NHE inhibitors described herein can generally be
combined in a beneficial manner with other compounds regulating the
intracellular pH, suitable combination partners being inhibitors of
the carbonic anhydratase enzyme group, inhibitors of the
bicarbonate ion-transporting systems such as the sodium-bicarbonate
cotransporter or the sodium-dependent chloride-bicarbonate
exchanger, and other NHE inhibitors, for example having an
inhibitory effect on other NHE subtypes, because the
pharmacologically relevant pH-regulating effects of the NHE
inhibitors described herein can be enhanced thereby.
[0092] Said compounds are therefore advantageously used for
producing a medicament for the prevention and treatment of sleep
apneas and muscle-related respiratory disorders; for producing a
medicament for the prevention and treatment of snoring; for
producing a medicament for lowering blood pressure; for producing a
medicament with a laxative effect for the prevention and treatment
of intestinal blockages; for producing a medicament for the
prevention and treatment of disorders induced by ischemia and
reperfusion of central and peripheral organs, such as acute renal
failure, stroke, endogenous states of shock, intestinal disorders
etc.; for producing a medicament for the treatment of late damage
from diabetes and chronic renal disorders, in particular of all
inflammations of the kidneys (nephritides) which are associated
with increased protein/albumin excretion; for producing a
medicament for the treatment of hypercholesterolemia; for producing
a medicament for the prevention of atherogenesis and of
atherosclerosis; for producing a medicament for the prevention and
treatment of diseases induced by elevated cholesterol levels; for
producing a medicament for the prevention and treatment of diseases
induced by endothelial dysfunction; for producing a medicament for
the treatment of infestation by ectoparasites; for producing a
medicament for the treatment of said disorders in combinations with
hypotensive substances, preferably with angiotensin converting
enzyme (ACE) inhibitors, with diuretics, aldosterone antagonists
and angiotensin receptor antagonists. A combination of an NHE
inhibitor of the formula I with an active ingredient lowering the
blood lipid level, preferably with an HMG-CoA reductase inhibitor
(e.g. lovastatin or pravastatin), the latter bringing about a
hypolipidemic effect and thus increasing the hypolipidemic
properties of the NHE inhibitor of the formula I, proves to be a
beneficial combination with enhanced effect and reduced use of
active ingredient.
[0093] The administration of sodium-proton exchange inhibitors of
the formula I as novel drugs for lowering elevated blood lipid
levels, and the combination of sodium-proton exchange inhibitors
with hypotensive drugs and/or drugs with hypolipidemic activity is
claimed.
[0094] The invention also relates to curative compositions for
human, veterinary or phytoprotective use comprising an effective
amount of a compound of the formula I and/or of a pharmaceutically
acceptable salt thereof, as well as curative compositions for
human, veterinary or phytoprotective use comprising an effective
amount of a compound of the formula I and/or of a pharmaceutically
acceptable salt thereof alone or in combination with one or more
other pharmacological active ingredients or drugs.
[0095] Drugs which comprise a compound I can in this connection be
administered orally, parenterally, intravenously, rectally,
transdermally or by inhalation, the preferred administration being
dependent on the particular characteristics of the disorder. The
compounds of the formula I may moreover be used alone or together
with pharmaceutical excipients, both in veterinary medicine and in
human medicine, and in crop protection.
[0096] The excipients suitable for the desired pharmaceutical
formulation are familiar to the skilled worker on the basis of his
expert knowledge. Besides solvents, gel formers, suppository bases,
tablet excipients, and other active ingredient carriers, it is
possible to use, for example, antioxidants, dispersants,
emulsifiers, antifoams, flavorings, preservatives, solubilizers or
colors.
[0097] For a form for oral administration, the active compounds are
mixed with additives suitable for this purpose, such as carriers,
stabilizers or inert diluents, and converted by conventional
methods into suitable dosage forms such as tablets, coated tablets,
hard gelatin capsules, aqueous, alcoholic or oily solutions.
Examples of inert carriers which can be used are gum arabic,
magnesia, magnesium carbonate, potassium phosphate, lactose,
glucose or starch, especially corn starch. It is moreover possible
for the preparation to take place both as dry granules and as wet
granules. Examples of suitable oily carriers or solvents are
vegetable or animal oils such as sunflower oil or fish liver
oil.
[0098] For subcutaneous or intravenous administration, the active
compounds used are converted, if desired with the substances
customary for this purpose, such as solubilizers, emulsifiers or
other excipients, into a solution, suspension or emulsion. Examples
of suitable solvents are: water, physiological saline or alcohols,
e.g. ethanol, propanol, glycerol, as well as sugar solutions such
as glucose or mannitol solutions, or else a mixture of the various
solvents mentioned.
[0099] Suitable as pharmaceutical formulation for administration in
the form of aerosols or sprays are, for example, solutions,
suspensions or emulsions of the active ingredient of the formula I
in a pharmaceutically acceptable solvent such as, in particular,
ethanol or water, or a mixture of such solvents.
[0100] The formulation may, if required, also contain other
pharmaceutical excipients such as surfactants, emulsifiers and
stabilizers, and a propellant gas. Such a preparation normally
contains the active ingredient in a concentration of about 0.1 to
10, in particular of about 0.3 to 3,% by weight.
[0101] The dosage of the active ingredient of the formula I to be
administered, and the frequency of administration, depend on the
potency and duration of action of the compounds used; additionally
also on the nature and severity of the disorder to be treated and
on the sex, age, weight and individual responsiveness of the mammal
to be treated.
[0102] On average, the daily dose of a compound of the formula I
for a patient weighing about 75 kg is at least 0.001 mg/kg,
preferably 0.1 mg/kg, to a maximum of 50 mg/kg, preferably 1 mg/kg,
of body weight. For acute episodes of the disorder, for example
immediately after suffering a myocardial infarction, higher and, in
particular, more frequent dosages may also be necessary, e.g. up to
4 single doses a day. Up to 200 mg/kg a day may be necessary, in
particular on i.v. administration, for example for a patient with
infarction in the intensive care unit.
[0103] Pharmaceutically acceptable salts are prepared for example
via the following acids: from inorganic acids such as hydrochloric
acid, sulfuric acid or phosphoric acid or from organic acids such
as acetic acid, citric acid, tartaric acid, lactic acid, malonic
acid, methanesulfonic acid, fumaric acid. Suitable acid addition
salts are salts of all pharmacologically acceptable acids, for
example halides, especially hydrochlorides, lactates, sulfates,
citrates, tartrates, acetates, phosphates, methylsulfonates,
p-toluene-sulfonates, adipates, fumarates, gluconates, glutamates,
glycerolphosphates, maleates and pamoates (this group also
corresponds to the physiologically acceptable anions); but also to
trifluoroacetates.
EXAMPLES
[0104] List of abbreviations used: [0105] Rt retention time [0106]
LCMS liquid chromatography mass spectroscopy [0107] MS mass
spectroscopy [0108] ES+electrospray, positive mode [0109] HPLC high
performance liquid chromatography
General:
[0110] The retention times (Rt) stated below relate to LCMS
measurements with the following parameters: [0111] Analytical
method: [0112] stationary phase: Merck Purospher 3 .mu.2.times.55
mm [0113] mobile phase: 95% H.sub.2O (0.1% HCOOH).fwdarw.95%
acetonitrile (0.1% HCOOH); 5 min.fwdarw.95% acetonitrile (0.1%
HCOOH); 2 min.fwdarw.95% H.sub.2O (0.1% HCOOH); 1 min; 0.45
m/min.
[0114] The preparative HPLC was carried out under the following
conditions: [0115] stationary phase: Merck Purospher RP18 (10
.mu.M) 250.times.25 mm [0116] mobile phase: 90% H.sub.2O (0.05%
TFA).fwdarw.90% acetonitrile; 40 min; 25 ml/min
Example 1
(1H-Benzoimidazol-2-yl)(2,6-dichlorophenyl)ethylamine
##STR00007##
[0118] (1H-Benzoimidazol-2-yl)(2,6-dichlorophenyl)amine (350 mg)
was dissolved in dimethylformamide (8 ml). Potassium carbonate (383
mg) was added to the resulting solution and, at 0.degree. C., ethyl
iodide (0.1 ml) was added dropwise while stirring. After stirring
at 0.degree. C. for half an hour, stirring was continued at room
temperature. 2.5 hours later, the reaction mixture was added to
ice-water, and the aqueous phase was extracted three times with
ethyl acetate. The combined organic extracts were washed with
saturated sodium chloride solution and subsequently dried over
magnesium sulfate. The residue after the solvent had been stripped
off in vacuo was purified by preparative HPLC. The
product-containing fractions were combined, the acetonitrile was
stripped off in a rotary evaporator, and the aqueous residue was
neutralized with potassium carbonate and extracted three times with
ethyl acetate. Drying over magnesium sulfate was followed by
evaporation to dryness and chromatography on silica gel with
dichloromethane/methanol 10/0.125. 12 mg of the desired compound
were obtained. [0119] LCMS-Rt: 2.25 min [0120] MS (ES.sup.+,
M+H.sup.+): 306.09
Example 2
(1H-Benzoimidazol-2-yl)(2,6-dichlorophenyl)methylamine
hydrochloride
##STR00008##
[0122] (1H-Benzoimidazol-2-yl)(2,6-dichlorophenyl)amine (500 mg)
was dissolved in methanol (50 ml). Potassium carbonate (220 mg) was
added to the resulting solution and, at room temperature, methyl
iodide (248 mg) was added dropwise while stirring vigorously, and
the mixture was then heated to reflux. After three days, the
reaction mixture was concentrated, the residue was partitioned
between ethyl acetate and water, and then the ethyl acetate phase
was separated off and dried. The residue after concentration in
vacuo was purified by preparative HPLC. The product-containing
fractions were combined, the acetonitrile was stripped off in a
rotary evaporator, and the aqueous residue was neutralized with
potassium carbonate and extracted three times with ethyl acetate.
Drying over magnesium sulfate was followed by evaporation to
dryness and chromatography on silica gel with ethyl acetate/heptane
1/1. After the product-containing fractions had been combined and
the solvent had been stripped off, the residue was taken up in
aqueous hydrochloric acid and freeze dried. 85 mg of the desired
compound were obtained. [0123] LCMS-Rt: 2.03 min [0124] MS
(ES.sup.+, M+H.sup.+): 292.05
[0125] Alternatively,
(1H-benzoimidazol-2-yl)(2,6-dichlorophenyl)methylamine
hydrochloride can also be obtained as follows:
a) (2,6-Dichlorophenyl)methylcyanamide
[0126] (2,6-Dichlorophenyl)cyanamide (1 g) was dissolved in dry
dimethylformamide (25 ml), powdered potassium carbonate (739 mg)
was added and then, while stirring, methyl iodide (1.52 g) was
added dropwise. After stirring at room temperature for two hours,
the reaction mixture was concentrated, the residue was taken up
with water and extracted three times with ether, and the combined
ether extracts were dried over magnesium sulfate. Filtration was
followed by evaporation to dryness and purification of the residue
by preparative HPLC. 600 mg of the desired product were
isolated.
[0127] .sup.1H-NMR (DMSO-d6/TMS, 400 MHz): 7.67 (d, 10 Hz, 2H),
7.50 (t, 10 Hz, 1H), 3.23 (s, 3H)
b) (1H-Benzoimidazol-2-yl)(2,6-dichlorophenyl)methylamine
hydrochloride
[0128] (2,6-Dichlorophenyl)methylcyanamide (150 mg) and
phenylenediamine (81 mg) were dissolved in hexafluoro-2-propanol (1
ml) and heated at 100.degree. C. in a closed vessel for 2 days.
After a further day at 60.degree. C. in an open vessel, the solvent
was removed and the residue was purified by preparative HPLC. The
product-containing fractions were combined, the acetonitrile was
stripped off in a rotary evaporator, and the aqueous residue was
neutralized with potassium carbonate and extracted three times with
ethyl acetate. Drying over magnesium sulfate and purification with
carbon were followed by evaporation to dryness. The residue was
taken up in aqueous hydrochloric acid and freeze dried. 5 mg of the
desired compound were obtained.
Example 3
(1H-Benzoimidazol-2-yl)(2,6-dichlorophenyl)isopropylamine
##STR00009##
[0130] In analogy to example 1,
(1H-benzoimidazol-2-yl)(2,6-dichlorophenyl)amine (250 mg) was
dissolved in dimethylformamide (3 ml), deprotonated with sodium
hydride (43 mg) and alkylated with isopropyl bromide (111 mg) in a
closed vessel at 100.degree. C. for one hour.
[0131] Workup and chromatography resulted in 21 mg of the desired
compound. [0132] LCMS-Rt: 2.30 min [0133] MS (ES.sup.+, M+H.sup.+):
320.16
Example 4
(2,6-Dichlorophenyl)(5-fluoro-1H-benzoimidazol-2-yl)methylamine
##STR00010##
[0135] In analogy to example 1,
(2,6-dichlorophenyl)(5-fluoro-1H-benzoimidazol-2-yl)amine (250 mg)
was dissolved in dimethylformamide (2 ml), deprotonated with sodium
hydride (45 mg) and alkylated with methyl iodide (120 mg) in a
closed vessel at 100.degree. C. Workup and chromatography resulted
in 19 mg of the desired compound. [0136] LCMS-Rt: 2.16 min [0137]
MS (ES.sup.+, M+H.sup.+): 310.12
Example 5
Allyl(1 H-benzoimidazol-2-yl)(2,6-dichlorophenyl)amine
##STR00011##
[0139] (1H-Benzoimidazol-2-yl)(2,6-dichlorophenyl)amine (250 mg)
was dissolved in dimethylformamide (2 ml) under argon in a
microwave-safe vessel, and sodium hydride (43 mg) was added. After
stirring at room temperature for one hour, cyclopropyl bromide (109
mg) was added dropwise, and the mixture was stirred for a further
half hour. The vessel was subsequently placed in the microwave
apparatus firstly for 10 min (80.degree. C., 100 W) and then for a
further 60 min (110.degree. C., 100 W). Further addition of
cyclopropyl bromide (55 mg) was followed by placing in the
microwave (110.degree. C., 100 W) once again for 60 min.
[0140] Workup and silica gel chromatography (see example 1)
resulted in 13 mg of the desired compound. [0141] LCMS-Rt: 2.28 min
[0142] MS (ES.sup.+, M+H.sup.+): 318.20
Example 6
(1H-Benzoimidazol-2-yl)cyclopentyl(2,6-dichlorophenyl)amine
##STR00012##
[0144] In analogy to example 1,
(1H-benzoimidazol-2-yl)(2,6-dichlorophenyl)amine (250 mg) was
dissolved in dimethylformamide (2 ml) at room temperature,
deprotonated with sodium hydride (48 mg) and alkylated with
cyclopentyl bromide (136.7 mg) in a closed vessel at 100.degree. C.
for 8 h.
[0145] Workup and chromatography resulted in 38 mg of the desired
compound. [0146] LCMS-Rt: 2.60 min [0147] MS (ES.sup.+, M+H.sup.+):
346.22
Experimentals
Description of Test
[0148] In this test, the recovery in the intracellular pH
(pH.sub.i) after an acidification was ascertained, which is
initiated if the NHE3 is capable of functioning, even under
bicarbonate-free conditions. For this purpose, the pH.sub.i was
determined using the pH-sensitive fluorescent dye BCECF
(Calbiochem, the precursor BCECF-AM is employed). The cells
(fibroblasts, LAP1 cells) were initially loaded with BCECF. The
BCECF fluorescence was determined in a "Ratio Fluorescence
Spectrometer" (Photon Technology International, South Brunswick,
N.J., USA) at excitation wavelengths of 505 and 440 nm and an
emission wavelength of 535 nm and converted into the pH.sub.i using
calibration curves. The cells were incubated in NH.sub.4Cl buffer
(pH 7.4) (NH.sub.4Cl buffer: 115 mM NaCl, 20 mM NH.sub.4Cl, 5 mM
KCl, 1 mM CaCl.sub.2, 1 mM MgSO.sub.4, 20 mM Hepes, 5 mM glucose, 1
mg/ml BSA; a pH of 7.4 is adjusted with 1 M NaOH) even during the
BCECF loading. The intracellular acidification was induced by
adding 975 .mu.l of an NH.sub.4Cl-free buffer (see below) to 25
.mu.l aliquots of the cells incubated in NH.sub.4Cl buffer. The
subsequent rate of pH recovery was recorded for three minutes. To
calculate the inhibitory potency of the tested substances, the
cells were initially investigated in buffers with which a complete
or absolutely no pH recovery took place. For complete pH recovery
(100%), the cells were incubated in Na.sup.+-containing buffer
(133.8 mM NaCl, 4.7 mM KCl, 1.25 mM CaCl.sub.2, 1.25 mM MgCl.sub.2,
0.97 mM Na.sub.2HPO.sub.4, 0.23 mM NaH.sub.2PO.sub.4, 5 mM Hepes, 5
mM glucose, a pH of 7.0 is adjusted with 1 M NaOH). To determine
the 0% value, the cells were incubated in an Na.sup.+-free buffer
(133.8 mM choline chloride, 4.7 mM KCl, 1.25 mM CaCl.sub.2, 1.25 mM
MgCl.sub.2, 0.97 mM K.sub.2HPO.sub.4, 0.23 mM KH.sub.2PO.sub.4, 5
MM Hepes, mM glucose, a pH of 7.0 is adjusted with 1 M KOH). The
substances to be tested were made up in the Na.sup.+-containing
buffer. The recovery of the intracellular pH at each test
concentration of a substance was expressed as a percentage of the
maximum recovery. The IC.sub.50 value for the particular substance
for the individual NHE subtypes was calculated from the pH recovery
percentages using the Sigma-Plot program.
Results
TABLE-US-00001 [0149] IC.sub.50 [.mu.M], Example (rNHE3) 1 0.57 2
0.53 3 9.3 4 3.3 5 1.5 6 8.3
* * * * *