Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D495/00—Heterocyclic compounds containing in the condensed system at least one hetero ring having sulfur atoms as the only ring hetero atoms
  • C07D495/02—Heterocyclic compounds containing in the condensed system at least one hetero ring having sulfur atoms as the only ring hetero atoms in which the condensed system contains two hetero rings
  • C07D495/04—Ortho-condensed systems
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
  • A61P25/00—Drugs for disorders of the nervous system
  • A61P25/08—Antiepileptics; Anticonvulsants
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
  • A61P25/00—Drugs for disorders of the nervous system
  • A61P25/14—Drugs for disorders of the nervous system for treating abnormal movements, e.g. chorea, dyskinesia
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
  • A61P25/00—Drugs for disorders of the nervous system
  • A61P25/28—Drugs for disorders of the nervous system for treating neurodegenerative disorders of the central nervous system, e.g. nootropic agents, cognition enhancers, drugs for treating Alzheimer's disease or other forms of dementia
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C229/00—Compounds containing amino and carboxyl groups bound to the same carbon skeleton
  • C07C229/02—Compounds containing amino and carboxyl groups bound to the same carbon skeleton having amino and carboxyl groups bound to acyclic carbon atoms of the same carbon skeleton
  • C07C229/04—Compounds containing amino and carboxyl groups bound to the same carbon skeleton having amino and carboxyl groups bound to acyclic carbon atoms of the same carbon skeleton the carbon skeleton being acyclic and saturated
  • C07C229/24—Compounds containing amino and carboxyl groups bound to the same carbon skeleton having amino and carboxyl groups bound to acyclic carbon atoms of the same carbon skeleton the carbon skeleton being acyclic and saturated having more than one carboxyl group bound to the carbon skeleton, e.g. aspartic acid
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C233/00—Carboxylic acid amides
  • C07C233/01—Carboxylic acid amides having carbon atoms of carboxamide groups bound to hydrogen atoms or to acyclic carbon atoms
  • C07C233/16—Carboxylic acid amides having carbon atoms of carboxamide groups bound to hydrogen atoms or to acyclic carbon atoms having the nitrogen atom of at least one of the carboxamide groups bound to a carbon atom of a hydrocarbon radical substituted by singly-bound oxygen atoms
  • C07C233/24—Carboxylic acid amides having carbon atoms of carboxamide groups bound to hydrogen atoms or to acyclic carbon atoms having the nitrogen atom of at least one of the carboxamide groups bound to a carbon atom of a hydrocarbon radical substituted by singly-bound oxygen atoms with the substituted hydrocarbon radical bound to the nitrogen atom of the carboxamide group by a carbon atom of a six-membered aromatic ring
  • C07C233/25—Carboxylic acid amides having carbon atoms of carboxamide groups bound to hydrogen atoms or to acyclic carbon atoms having the nitrogen atom of at least one of the carboxamide groups bound to a carbon atom of a hydrocarbon radical substituted by singly-bound oxygen atoms with the substituted hydrocarbon radical bound to the nitrogen atom of the carboxamide group by a carbon atom of a six-membered aromatic ring having the carbon atom of the carboxamide group bound to a hydrogen atom or to a carbon atom of an acyclic saturated carbon skeleton
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C233/00—Carboxylic acid amides
  • C07C233/01—Carboxylic acid amides having carbon atoms of carboxamide groups bound to hydrogen atoms or to acyclic carbon atoms
  • C07C233/16—Carboxylic acid amides having carbon atoms of carboxamide groups bound to hydrogen atoms or to acyclic carbon atoms having the nitrogen atom of at least one of the carboxamide groups bound to a carbon atom of a hydrocarbon radical substituted by singly-bound oxygen atoms
  • C07C233/24—Carboxylic acid amides having carbon atoms of carboxamide groups bound to hydrogen atoms or to acyclic carbon atoms having the nitrogen atom of at least one of the carboxamide groups bound to a carbon atom of a hydrocarbon radical substituted by singly-bound oxygen atoms with the substituted hydrocarbon radical bound to the nitrogen atom of the carboxamide group by a carbon atom of a six-membered aromatic ring
  • C07C233/29—Carboxylic acid amides having carbon atoms of carboxamide groups bound to hydrogen atoms or to acyclic carbon atoms having the nitrogen atom of at least one of the carboxamide groups bound to a carbon atom of a hydrocarbon radical substituted by singly-bound oxygen atoms with the substituted hydrocarbon radical bound to the nitrogen atom of the carboxamide group by a carbon atom of a six-membered aromatic ring having the carbon atom of the carboxamide group bound to an acyclic carbon atom of a carbon skeleton containing six-membered aromatic rings
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C233/00—Carboxylic acid amides
  • C07C233/57—Carboxylic acid amides having carbon atoms of carboxamide groups bound to carbon atoms of rings other than six-membered aromatic rings
  • C07C233/60—Carboxylic acid amides having carbon atoms of carboxamide groups bound to carbon atoms of rings other than six-membered aromatic rings having the nitrogen atom of at least one of the carboxamide groups bound to a carbon atom of a hydrocarbon radical substituted by singly-bound oxygen atoms
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C233/00—Carboxylic acid amides
  • C07C233/64—Carboxylic acid amides having carbon atoms of carboxamide groups bound to carbon atoms of six-membered aromatic rings
  • C07C233/67—Carboxylic acid amides having carbon atoms of carboxamide groups bound to carbon atoms of six-membered aromatic rings having the nitrogen atom of at least one of the carboxamide groups bound to a carbon atom of a hydrocarbon radical substituted by singly-bound oxygen atoms
  • C07C233/75—Carboxylic acid amides having carbon atoms of carboxamide groups bound to carbon atoms of six-membered aromatic rings having the nitrogen atom of at least one of the carboxamide groups bound to a carbon atom of a hydrocarbon radical substituted by singly-bound oxygen atoms with the substituted hydrocarbon radical bound to the nitrogen atom of the carboxamide group by a carbon atom of a six-membered aromatic ring
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C235/00—Carboxylic acid amides, the carbon skeleton of the acid part being further substituted by oxygen atoms
  • C07C235/42—Carboxylic acid amides, the carbon skeleton of the acid part being further substituted by oxygen atoms having carbon atoms of carboxamide groups bound to carbon atoms of six-membered aromatic rings and singly-bound oxygen atoms bound to the same carbon skeleton
  • C07C235/44—Carboxylic acid amides, the carbon skeleton of the acid part being further substituted by oxygen atoms having carbon atoms of carboxamide groups bound to carbon atoms of six-membered aromatic rings and singly-bound oxygen atoms bound to the same carbon skeleton with carbon atoms of carboxamide groups and singly-bound oxygen atoms bound to carbon atoms of the same non-condensed six-membered aromatic ring
  • C07C235/56—Carboxylic acid amides, the carbon skeleton of the acid part being further substituted by oxygen atoms having carbon atoms of carboxamide groups bound to carbon atoms of six-membered aromatic rings and singly-bound oxygen atoms bound to the same carbon skeleton with carbon atoms of carboxamide groups and singly-bound oxygen atoms bound to carbon atoms of the same non-condensed six-membered aromatic ring having the nitrogen atom of at least one of the carboxamide groups bound to a carbon atom of a six-membered aromatic ring
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C237/00—Carboxylic acid amides, the carbon skeleton of the acid part being further substituted by amino groups
  • C07C237/02—Carboxylic acid amides, the carbon skeleton of the acid part being further substituted by amino groups having the carbon atoms of the carboxamide groups bound to acyclic carbon atoms of the carbon skeleton
  • C07C237/04—Carboxylic acid amides, the carbon skeleton of the acid part being further substituted by amino groups having the carbon atoms of the carboxamide groups bound to acyclic carbon atoms of the carbon skeleton the carbon skeleton being acyclic and saturated
  • C07C237/08—Carboxylic acid amides, the carbon skeleton of the acid part being further substituted by amino groups having the carbon atoms of the carboxamide groups bound to acyclic carbon atoms of the carbon skeleton the carbon skeleton being acyclic and saturated having the nitrogen atom of at least one of the carboxamide groups bound to an acyclic carbon atom of a hydrocarbon radical substituted by singly-bound oxygen atoms
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C237/00—Carboxylic acid amides, the carbon skeleton of the acid part being further substituted by amino groups
  • C07C237/02—Carboxylic acid amides, the carbon skeleton of the acid part being further substituted by amino groups having the carbon atoms of the carboxamide groups bound to acyclic carbon atoms of the carbon skeleton
  • C07C237/22—Carboxylic acid amides, the carbon skeleton of the acid part being further substituted by amino groups having the carbon atoms of the carboxamide groups bound to acyclic carbon atoms of the carbon skeleton having nitrogen atoms of amino groups bound to the carbon skeleton of the acid part, further acylated
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C255/00—Carboxylic acid nitriles
  • C07C255/49—Carboxylic acid nitriles having cyano groups bound to carbon atoms of six-membered aromatic rings of a carbon skeleton
  • C07C255/57—Carboxylic acid nitriles having cyano groups bound to carbon atoms of six-membered aromatic rings of a carbon skeleton containing cyano groups and carboxyl groups, other than cyano groups, bound to the carbon skeleton
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
  • C07F7/00—Compounds containing elements of Groups 4 or 14 of the Periodic Table
  • C07F7/02—Silicon compounds
  • C07F7/08—Compounds having one or more C—Si linkages
  • C07F7/18—Compounds having one or more C—Si linkages as well as one or more C—O—Si linkages
  • C07F7/1804—Compounds having Si-O-C linkages
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C2601/00—Systems containing only non-condensed rings
  • C07C2601/12—Systems containing only non-condensed rings with a six-membered ring
  • C07C2601/14—The ring being saturated

Definitions

• the present invention relates to L-glutamate uptake inhibitors, and more specifically, it relates to derivatives of optically active L-threo- ⁇ -benzyloxyaspartate having an amino substituent on the benzene ring, represented by the following formula (1) and having activity which inhibits uptake of glutamate by L-glutamate transporters.
• R is hydrogen, a linear or branched lower aliphatic acyl group with the acyl portion optionally substituted, an alicyclic acyl group, an aromatic acyl group with a substituent on the aromatic ring, an amino acid-derived group or a biotin derivative-derived group.
• L-glutamate is a excitatory neurotransmitter found in the central nervous system of mammals, and it is known not only to induce rapid neurotransmission between synapses but also to be involved on a higher level in the complex physiological processes of memory and learning.
• Excitatory neurotransmission between synapses begins with release of glutamate from the presynapse, and fades with rapid glutamate uptake from the synaptic cleft by high-affinity glutamate transporters found in nerve endings and glial cells (Attwell, D. and Nicholls, D., TIPS 68-74, 1991).
• Reduced sodium-dependent glutamate uptake activity in portions of patient brains has been reported in several genetic neurodegenerative diseases (Rothstein, J.D.
• EAAT1 to EAAT5 were categorized (Arriza, J.L. et al., J. Neurosci. 14, 5559-5569; Fairman, W.A. et al., Nature, 375, 599-603, 1995; Arriza, J.L. et al., Proc. Natl. Acad. Sci. USA 94, 4155-4160, 1997).
• glutamate transporter inhibitors and especially inhibitors that function as blockers, toward elucidation of the relationship between the glutamate transporter family and neuropathic disorders and neurodegenerative diseases such as epilepsy, Huntington's disease, amyotrophic lateral sclerosis (ALS) and Alzheimer's disease.
• ALS amyotrophic lateral sclerosis
• trans-pyrrolidine-2,4-dicarboxylic acid and the like have hitherto been identified as glutamate uptake inhibitors, and these are themselves taken up as substrates by transporters and thus act as inhibitors that competitively inhibit glutamate uptake.
• the glutamate uptake inhibitors such as kainic acid and dihydrokainic acid were demonstrated by electrophysiological studies to be blockers that inhibit glutamate uptake without themselves being taken up. It was further shown that these compounds act only on EAAT2 (GLT-1 type) of the five EAAT subtypes (Arriza, J.L. et al. , J. Neurosci. 14, 5559-5569, 1994). Nevertheless, these compounds have also exhibited strong excitatory effects on ion-channel glutamate receptors. The present inventors have reported that ⁇ - hydroxyaspartate derivatives having substituents at the ⁇ - position exhibit an uptake-inhibiting effect for all of the five EAAT subtypes (Lebrun, B.
• L-TBOA L-threo- ⁇ -benzyloxyaspartate
• protein purification is essential for elucidating the 3-dimensional structure of the glutamate transporter and shedding light on the substrate transport mechanism and substrate-binding site.
• affinity column chromatography is an effective means of protein purification. Protein purification using antibodies has already been attempted, but this has been inconvenient because the strong binding between the antibodies and the protein results in loss of the original protein function upon elution. Using a blocker as the column ligand would allow elution under mild conditions, and therefore blockers having substituents that can bind to affinity columns have also been a target of research.
• acyl groups as substituents function as glutamate transporter inhibitors with inhibiting action equivalent to or exceeding that of TBOA.
• compounds having a benzoyl derivative were found to exhibit vastly increased activity and were superior to TBOA as inhibitors.
• compounds having amino acids as substituents permit ready binding between the free amino groups and carboxyli ⁇ or halogenated alkyl groups of commercially available column carriers.
• compounds with biotinyl groups allow binding with commercially available avidin columns. It was thus found that these compounds allow sufficient binding to column carriers while maintaining blocker activity, and the present invention was thereby completed.
• the present invention provides derivatives of optically active ⁇ -benzyloxyaspartate having an amino substituent on the benzene ring, represented by chemical formula (1), and salts thereof, as glutamate transporter blockers and as . affinity column ligands.
• R is hydrogen, a linear or branched lower aliphatic acyl group with the acyl portion optionally substituted, an alicyclic acyl group, an aromatic acyl group with a substituent on the aromatic ring, an amino acid-derived group or a biotin derivative-derived group. More specifically, in formula (1), R is hydrogen, a linear or branched lower aliphatic acyl group, a C 4 -C 8 alicyclic acyl group, a C 5 -C 15 aromatic acyl group, an amino acid derivative or a biotin derivative.
• linear or branched lower aliphatic and alicyclic acyl groups represented by R include acetyl, propionyl, n-butanoyl, sec-butanoyl, n- pentanoyl, pivaloyl, phenylacetyl and cyclohexyl ⁇ arbonyl. Substituents may also be present on the acyl group and examples of substtituents include hydroxyl group, thiol group, amino group and carboxyl group.
• aromatic acyl groups represented by R include benzoyl, naphthoyl and pyridylcarbonyl. Substituents may also be present on the aromatic ring.
• substituents on the aromatic ring include linear or branched alkoxyl, nitro, cyano, amino, C x -C 7 a ⁇ ylamino, carboxyl, halogen, halogenated alkyl, biotinyl, and biotinylalkyl with the alkyl portion being Ci-Cg, and the like.
• amino acids represented by R include glycyl, alanyl, ⁇ -alanyl and cysteinyl.
• biotin derivatives represented by R include biotinyl and biotinyl- ⁇ -alanyl.
• the compounds of the invention may be obtained as salts by ordinary methods .
• Alkali metal salts such as sodium salts and potassium salts and alkaline earth metal salts such as calcium salts, as well as ammonium salts, are all included as such salts according to the invention. Salts may also be obtained with ordinary acids. Inorganic acid salts such as hydrochloric acid salts and sulfuric acid salts, and organic acid salts such as acetic acid salts , citric acid salts and trifluoroacetic acid salts are also included as such salts according to the invention.
• the position of the substituent on the benzene ring may be any one of the three positions of ortho-, meta- or para-, according to the invention.
• study of the structure/activity relationship of the compounds has revealed that in the case where an amino group is positioned on the benzene ring, the meta-position of the amino group provides strongest activity.
• the synthesis scheme below therefore, shows examples of introduction for obtaining compounds with substituents at the meta-position; nevertheless, agents with different substitution patterns may be used for introduction of desired substituents.
• the compounds of the invention may be synthesized in the following manner.
• compounds wherein R is ⁇ - alanyl, biotinyl- ⁇ -alanyl or propionyl- ⁇ -alanyl may be synthesized according to the following scheme.
• an optically active starting material may be used for compound (1) in the above scheme.
• the hydroxyl- protecting group of the compound is first removed with an alkali metal hydroxide such as NaOH and then the resulting free hydroxyl group is reacted with a benzoylisocyanate to obtain the benzoylcarbamate represented by formula (2).
• the benzoylisocyanate is added to a THF (tetrahydrofuran) solution in approximately 1.2 equivalents at room temperature, and the mixture is stirred for about 30 minutes.
• the compound of formula (2) is reacted in the presence of a catalytic amount of tetrabutylammonium iodide under weakly basic conditions, to produce a mixture of the L-threo cyclocarbamates represented by formula (3a) and formula (3b).
• potassium carbonate is added at approximately 2 equivalents and tetrabutylammonium iodide in approximately 0.15 equivalent to an acetonitrile solution, and the mixture is stirred at room temperature for from 14 hours to 18 hours.
• This synthesis method of the invention selectively yields a L-threo cyclocarbamate mixture as a production intermediate.
• compound (6) was used as the substrate instead of the known lactone intermediate (Bioorg. Med. Chem. Lett. 10, 2407-2410, 2000), in order to suppress isomerization to the erythro-form. While isomerization of about 30% is seen with the conventional substrate, using the present compound results in only trace amounts, rendering it a more threo-selective production method.
• reaction conditions sodium hydride is added at approximately 1.5 equivalents and tetrabutylammonium iodide at approximately 0.3 equivalent to a DMF solution of compound (6) cooled to about -20°C, and then nitrobenzyl bromide (preferably 3-nitrobenzyl bromide) is added at approximately 1.5 equivalents and the mixture is stirred at about -20°C for about 30 minutes and then at about 0°C for about 30 minutes.
• nitrobenzyl bromide preferably 3-nitrobenzyl bromide
• the yield can be greatly improved by using a nitro group as the amino equivalent, since when a 3-protected-aminobenzyl bromide is used instead of 3-nitrobenzyl bromide, the reaction will not proceed sufficiently even with a prolonged reaction time and an increased temperature.
• Compound (7) obtained by this reaction can then be easily converted to the corresponding amino compound by reduction of the nitro group. Subsequent acylation by reaction with an acid chloride or carboxylic acid and a condensation agent can convert it to a compound having the desired substituent. Compound (7) is therefore useful as an intermediate for synthesis of the target amino-substituted benzyloxyaspartate.
• Well-known methods can be used to determine inhibitory activity of the compounds of the invention on glutamate transporters .
• the compounds of the invention have been confirmed to inhibit uptake of 1 C-labeled glutamate into cells by human EAAT2 and EAAT3 stably expressed on MDCK (Madin-Darby Canine Kidney) cells or transiently expressed on COS-1 cells.
• MDCK Medin-Darby Canine Kidney
• COS-1 cells transiently expressed on COS-1 cells.
• Some of the Compounds of formula (1) may be used as ligands of an affinity column for isolation and/or purification of glutamate transporter proteins.
• Well-known methods may be used to prepare an affinity column.
• a liquid sample suspected of containing a target protein may be introduced into a column prepared as described above.
• the liquid flow is suspended to incubate the column for a certain period, e.g., about 30 min.
• the protein is eluted with an elution buffer (e.g., 0.1 M HC1, pH 2.2). If necessary, the protein solution is passed through a desalting column to remove the salt.
• an elution buffer e.g., 0.1 M HC1, pH 2.2
• Some compounds of formula (1) are useful for radio- isotope labeled ligands for identification of transporter proteins.
• Isotope labeled ligands may be obtained by well known synthetic procedures, using the hydroxybenzoyl intermediate for R group in the formula (1) with the reaction, for example, of labeled methyl iodide to yield the desired labeled ligand as shown in Scheme 2.
• Some of the radio-isotope labeled methyl iodides are commercially available, including, deuterium-labeled methyl iodide, tritium-labeled methyl iodide. Carbon 14-labeld or Carbon 11-labeled methyl iodides.
• Diazomethane was added to the organic layer for methyl esterification, and the solution was dried over magnesium sulfate. The solvent was distilled off, the obtained residue was dissolved in 100 mL of THF, and a THF solution (I N, 11 mL) containing tetra-n-butylammonium fluoride was added. Ethyl acetate was added for extraction, and the organic layer was washed with a 5% citric acid aqueous solution.
• the organic layer was then dried over magnesium sulfate, and the lactone and diol mixture obtained by distilling off the solvent was dissolved in methanol, after which a catalytic amount of acidic resin (Amberlyst 15E) was added and the mixture was stirred for 16 hours .
• the catalyst was filtered off, the solvent was distilled off, the obtained residue was dissolved in DMF, and then t-butyldimethylsilyl chloride (828 mg, 5.5 mmol) and imidazole (748 mg, 11 mmol) were added and the mixture was stirred at room temperature for 3 hours .
• the catalyst was filtered off, the residue obtained by concentrating the filtrate was dissolved in 2 mL of methylene chloride, 1 mL of trifluoroacetic acid was added and the mixture was stirred for 15 minutes. The solvent was distilled off, the residue was subjected to Dowex 50 x 100 column chromatography and washed with water, and then elution was performed with IN ammonia water. Lyophilization was repeated to obtain the title compound (97 mg, 91%).
• a catalytic amount of palladium carbon (10%) was added to 5 mL of a methanol solution containing compound (8) (107 mg, 0.20 mmol), and the mixture was stirred for 3 hours under a hydrogen atmosphere.
• the catalyst was filtered off, the residue obtained by concentrating the filtrate was dissolved in 2 mL of methylene chloride, and then biotin, pentafluorophenyl ester (91 mg, 0.22 mmol) and triethylamine (30 ⁇ L, 0.22 mmol) were added and the mixture was stirred at room temperature for 30 minutes.
• the reaction solution was diluted with ether, and washed with IN hydrochloric acid and water.
• the organic layer was dried over magnesium sulfate.
• the organic layer was dried over magnesium sulfate, and the residue obtained by distilling off the solvent was dissolved in 1 mL of chloroform prior to adding 1 mL of trifluoroacetic acid and stirring for 15 minutes.
• the solvent was distilled off, the residue was subjected to Dowex 50 x 100 column chromatography and washed with water, and then elution was performed with IN ammonia water. Lyophilization was repeated to obtain 7.9 mg of the title compound (72%).
• a catalytic amount of palladium carbon (10%) was added to 10 mL of a methanol solution containing compound (8) (110 mg, 0.16 mmol), and the mixture was stirred for 3 hours under a hydrogen atmosphere.
• the catalyst was filtered off, and the filtrate was concentrated under reduced pressure.
• the residue was dissolved in 10 mL of methylene chloride, and then triethylamine (45 ⁇ L, 0.32 mmol) and propionyl chloride (16 ⁇ L, 0.19 mmol) were added while cooling on ice and the mixture was stirred for 15 minutes.
• a catalytic amount of DL-camphorsulfonic acid was added to 10 mL of a methanol solution containing compound (11) (57 mg, 0.096 mmol) and the mixture was stirred for 3 hours. Ether and water were added for extraction, and the organic layer was dried over magnesium sulfate. The solvent was distilled off, the resulting residue was dissolved in 5 mL of acetone, and Jones reagent was added at 0°C until the solution brownness no longer disappeared. 2-Propanol was added to quench the reaction, and extraction was performed with ether.
• the aqueous layer was adjusted to pH 2 with 2N hydrochloric acid, and extraction was again performed into an organic layer with ethyl acetate.
• the organic layer was dried over magnesium sulfate and the residue obtained by distilling off the solvent was dissolved in 1 mL of methanol, after which 1 mL of a IN sodium hydroxide aqueous solution was added and the mixture was stirred at room temperature for 18 hours.
• the reaction solution was adjusted to pH 1 with 2N hydrochloric acid, and extraction was performed with ethyl acetate.
• the organic layer was dried over magnesium sulfate, and the residue obtained by distilling off the solvent was dissolved in 1 mL of chloroform prior to adding 1 L of trifluoroacetic acid and stirring for 15 minutes.
• the solvent was distilled off, the residue was subjected to Dowex 50 x 100 column chromatography and washed with water, and then elution was performed with IN ammonia water. Lyophilization was repeated to obtain 14 mg of the title compound (5 steps, 39%).
• a para-substituted form (p-Pr-A-TBOA) was also synthesized by the same method.
• the glutamate uptake activity was measured by adding 1 ⁇ M of L- [ 14 C]glutamate and a prescribed concentration of sample, incubating for 12 minutes and then lysating the cells, and using a liquid scintillator to determine the radioactivity uptake.
• the uptake was expressed as a percentage, with 100% being the uptake with no compound (buffer alone) and 0% being the uptake with a sodium-free solution.
• the IC 50 values are shown in Table 1. Table 1
• the "*" indicates results obtained using COS-1 cells, and the other results were obtained using MDCK cells.
• the results show that the inhibitory effect of the compounds of the invention on uptake of [ 14 C]glutamate by human EAAT2 and EAAT3 is at least comparable to, or in some compounds, remarkably higher than that of TBOA. Besides, it will be appreciated that the inhibitory effect of some compounds in table 1 is selective to EAAT2 over EAAT3.
• a compound of the invention (ligand) is solubilized in a coupling buffer (e.g., 0.1 M NaHC0 3 containing 0.5 M NaCl, pH 8.3).
• the ligand solution is mixed with the gel suspension for two hours at an ambient temperature or overnight at 4 °C .
• a blocking agent such as 1 M ethanolamine or 0.2 M glycine, pH 8.0.
• the gel is washed with the coupling buffer and acetate buffer (0.5 M NaCl, 0.1 M AcOH, pH 4) in that order to remove excess ligand and blocking agent.
• the gel is stored at 4-8°C.
• ECH Sepharose 4B (Amersham Biosciences) is weighed on a glass filter and washed with 0.5 M NaCl.
• a compound of the invention (ligand) is solubilized in water, which is then adjusted at pH 4.5.
• An aqueous solution of carbodiimide is prepared and the pH of the solution is adjusted at pH 4.5.
• the swollen gel, the ligand solution and the carbodiimide solution are mixed to allow to react at an ambient temperature overnight. Excess ligand, urea derivatives and remaining ligand are removed by washing.
• the gel is stored at 4-8 ⁇ .
• Immobilized avidin or streptavidin slury is poured into a column.
• the packed column is equilibrated with 5 column volumes of binding buffer (e.g., PBS).
• a biotinylated compound of the invention is applied to the column and the column is incubated for 30 min.
• the column is washed with 10 column volumes of binding buffer.

Landscapes

• Organic Chemistry (AREA)
• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Neurosurgery (AREA)
• Engineering & Computer Science (AREA)
• Bioinformatics & Cheminformatics (AREA)
• Biomedical Technology (AREA)
• Neurology (AREA)
• Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
• Veterinary Medicine (AREA)
• General Chemical & Material Sciences (AREA)
• Medicinal Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Pharmacology & Pharmacy (AREA)
• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Pain & Pain Management (AREA)
• Hospice & Palliative Care (AREA)
• Psychiatry (AREA)
• Psychology (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Acyclic And Carbocyclic Compounds In Medicinal Compositions (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Related Child Applications (2)

Publications (1)

Family

ID=19028851

Family Applications (1)

Country Status (4)

Cited By (5)

Families Citing this family (4)

Citations (2)

• 2002
  • 2002-06-24 JP JP2003507101A patent/JP4542336B2/ja not_active Expired - Lifetime
  • 2002-06-24 EP EP02743696.3A patent/EP1397370B1/en not_active Expired - Lifetime
  • 2002-06-24 US US10/481,237 patent/US7247652B2/en not_active Expired - Lifetime
  • 2002-06-24 WO PCT/JP2002/006286 patent/WO2003000698A1/en not_active Ceased
• 2007
  • 2007-06-14 US US11/808,970 patent/US7666906B2/en not_active Expired - Lifetime

Patent Citations (2)

Non-Patent Citations (2)

Also Published As

Similar Documents

Legal Events