EP2271644A1 - Substituted piperidines as therapeutic compounds - Google Patents

Substituted piperidines as therapeutic compounds

Info

Publication number
EP2271644A1
EP2271644A1 EP09728288A EP09728288A EP2271644A1 EP 2271644 A1 EP2271644 A1 EP 2271644A1 EP 09728288 A EP09728288 A EP 09728288A EP 09728288 A EP09728288 A EP 09728288A EP 2271644 A1 EP2271644 A1 EP 2271644A1
Authority
EP
European Patent Office
Prior art keywords
methoxy
straight
chain
methyl
acid
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP09728288A
Other languages
German (de)
French (fr)
Inventor
Peter Herold
Robert Mah
Stefan Stutz
Vincenzo Tschinke
Aleksandar Stojanovic
Dirk Behnke
Stjepan Jelakovic
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Novartis AG
Original Assignee
Novartis AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Novartis AG filed Critical Novartis AG
Priority to EP09728288A priority Critical patent/EP2271644A1/en
Publication of EP2271644A1 publication Critical patent/EP2271644A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D413/00—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and oxygen atoms as the only ring hetero atoms
    • C07D413/02—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and oxygen atoms as the only ring hetero atoms containing two hetero rings
    • C07D413/12—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and oxygen atoms as the only ring hetero atoms containing two hetero rings linked by a chain containing hetero atoms as chain links
    • 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
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P31/00—Antiinfectives, i.e. antibiotics, antiseptics, chemotherapeutics
    • A61P31/12—Antivirals
    • A61P31/14—Antivirals for RNA viruses
    • A61P31/18—Antivirals for RNA viruses for HIV
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P33/00—Antiparasitic agents
    • A61P33/02—Antiprotozoals, e.g. for leishmaniasis, trichomoniasis, toxoplasmosis
    • A61P33/06—Antimalarials
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P43/00—Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00

Definitions

  • the present invention relates to the use of substituted piperidines as beta-secretase-, cathepsin D-, plasmepsin II- and/or HIV-protease-inhibitors.
  • beta-secretase-, cathepsin D-, plasmepsin II- and/or HlV-protease- inhibition there is still a need for highly potent active ingredients.
  • the improvement of the pharmacokinetic properties is at the forefront. These properties directed towards better bioavailability are, for example, absorption, metabolic stability, solubility or lipophilicity.
  • Alzheimer Disease aspartyl protease Beta-Secretase
  • AD Alzheimer's disease
  • the symptoms of AD include progressive memory loss, language difficulty and ultimately loss of basic neural function and death.
  • the biomarkers in the central nervous system for AD include amyloid plaques, intracellular neurofibrillary tangles and activated microglia. The appearance of these three markers is likely to contribute to the neuronal cell death and memory loss observed in AD.
  • Beta-amyloid is a defining feature of AD and now believed to be a causative precursor in the development of the disease.
  • Amyloidogenic plaques and vascular amyloid angiopathy also characterize the brains of individuals with Trisomy 21 (Down's Syndrome), Hereditary Cerebral Hemorrhage with Amloidosis of the Dutch-Type (HCHWA-D) and other neurodegenerative disorders.
  • Beta-amyloid plaques are predominantly composed of amyloid beta peptide (A-beta, also sometimes designated betaA4).
  • the A-beta peptide is derived by proteolysis of the beta amyloid precursor protein (APP).
  • Beta-APP is processed by three distinct ordered enzymatic activities.
  • the bulk of beta-APP is processed via alpha-secretase in a non-amyloidogenic pathway.
  • a small fraction of beta-APP is cleaved by beta- secretase activity to generate the membrane-bound C-terminal fragment C99.
  • Gamma-secretase cleaves C99 to generate the amyloidogenic A-beta peptide of 39-42 amino acids.
  • the aspartyl protease activity of beta-secretase has been disclosed using varied nomenclature, including BACE (beta-site APP cleaving enzyme), Asp and memapsin.
  • beta-secretase cleavage of beta-APP as a critical step in the generation of AD is underscored by the observation that human mutations at the beta-secretase cleavage subsites (Swedish mutations) of beta-APP lead to increased A-beta production and early onset familial AD. Furthermore, BACE1 - knockout mice fail to produce A-beta peptide and present a normal phenotype. When crossed with transgenic mice that overexpress APP, the progeny show reduced amounts of A-beta in brain extracts as compared with control animals.
  • Beta-secretase inhibiting compounds as discussed by Thompson et al. (2005) in Curr. Pharm. Des. 11 , 3383-3404 are therefore useful to treat or to prevent diseases that are characterized by amyloid beta deposits or plaques such as AD.
  • the present invention also relates to methods of treating subjects who have, or in preventing subjects from developing a disease or condition selected from the group consisting of AD, for helping prevent or delay the onset of AD, for helping to slow the proression of AD, for treating subjects with mild cognitive impairment (MCI) and preventing or delaying the onset of AD in those who could progress form MCI to AD, for treating Down's syndrome, for treating humans who have HCHWAD, for treating cerebral amyloid angiopathy, and for treating degenerative dementias Alzheimer's Disease aspartyl protease: Cathepsin D
  • Human cathepsin D is an intracellular aspartic peptidase found mainly in lysosomes. It has a number of housekeeping functions, including the degradation of cellular and phagocytosed proteins. The enzymes may be involved in a variety of disease states, including cancer and Alzheimer's disease (AD). Clinical studies have shown that cathepsin D is overexpressed in breast cancer cells and this seems to be associated with an increased risk for metastasis due to enhanced cell growth. Cathepisn D is also thought to be involved in formation of the beta-amyloid peptide in AD. Recently, several genetic association studies linked cathepsin D with amyloid pathology and Alzheimer's disease as described for example by Davidson et al., (2006) in J. Neurol. Neurosurg. Psychiatry 77, 515-517. The availability of selective and potent inhibitors will help to further define the role of cathepsin D in disease and possibly lead to therapeutic agents.
  • Plasmodium falciparum Malaria is considered as one of the most serious infectious diseases in the world, affecting approximately 500 million people. The disease is spread by the anopheles mosquito that is mostly found in tropical regions. The species Plasmodium falciparum is responsible for more than 95% of malaria-related morbidity and mortality. Increasingly, Plasmodium falciparum is becoming resistant to existing therapies such as chloroquine, mefloquine and sulfadoxime/ pyrimethamine. Thus there is an urgent need for new treatments.
  • the parasite In the erythrocytic stage of the parasite's life cycle the parasite invades the red blood cells of its host consuming up to 80% of the hemoglobin as a source of nutrients for growth and development. Hemoglobin degradation takes place in an acidic vacuole of the parasite and many of the current antimalarial drugs appear to disrupt important vacuolar functions.
  • the food vacuole contains aspartic, cysteine and metallo- proteases, which are all considered to play a role in the process of hemoglobin degradation. At least 10 genes encoding aspartic proteases have been identified in the Plasmodium genome.
  • plasmepsin I, II, IV and HAP plasmepsin I, II, IV and HAP
  • Inhibitors of plasmepsin I and Il have shown efficacy in cell and animal models of malaria, indicating that these enzymes may represent targets for drug discovery as described for example by Coombs et al. (2001 ) Trends Parasitol 17, 532-537.
  • a non-selective inhibitor of aspartic proteases, pepstatin inhibits the growth of Plasmodium falciparum in vitro.
  • the present invention relates to the identification of low molecular weight, non- peptidic inhibitors of the Plasmodium falciparum protease plasmepsin Il or other related aspartic proteases to treat and/or to prevent malaria.
  • HIV aspartyl protease HIV-1 peptidase
  • AIDS Acquired immunodeficiency syndrome
  • Gag and Gag-Pol Two polyprotein precursors, Gag and Gag-Pol.
  • the 55-kDa Gag precursor contains the structural proteins and the 160-kDa Gag-Pol polyprotein contains the functional viral enzymes protease, reverse transcriptase, and integrase.
  • Gag and Gag-Pol polyproteins are transported to the plasma membrane where assembly of type-C retroviruses and lentiviruses typically occurs.
  • the viral protease cleaves the Gag and Gag-Pol precursors into the structural and functional proteins required for viral replication.
  • the protease activity within the cytoplasma of infected cells allows for the formation of virions which can be released from the cell in the last stages of budding.
  • the mature HIV-1 protease is an obligatory dimer of identical 11 -kDa subunits, each contributing one of the two catalytic aspartic residues.
  • the cell-derived members of the aspartic protease family are monomehc enzymes with two Asp-Thr- Gly-containing domains.
  • the unique dimeric structure of the retroviral protease is mainly stabilized by an antiparallel beta-sheet formed by the interdigitation of the amino- and carboxyl-terminal beta-strands of each monomer.
  • HIV-1 protease i.e. the dimerization and autocatalytic release from Gag-Pol
  • Inhibition of protease activation causes a severe defect in Gag polyprotein processing and a complete loss of viral infectivity.
  • the viral protease has become a target for HIV therapeutics, resulting in many HIV protease inhibitors reaching clinical trials as reviewed by Rana et al. (1999) in Pharmacotherapy 19, 35-59 and Morse et al., (2006) in Lancet Infect. Dis. 6, 215-225.
  • Most of these drugs are substrate-based inhibitors, whose design has been facilitated by an abundance of crystal structure data for both the native enzyme and enzyme- inhibitor complexes. Additionally, there are now extensive biochemical data detailing both the catalytic mechanism and the molecular basis for substrate selection.
  • the present invention relates to compounds of the general formula
  • R 1 is straight-chain Ci-s-alkanoyloxy, straight-chain Ci-s-alkoxy, straight-chain Ci-S- alkoxy-straight-chain-Ci-s-alkoxy, straight-chain Ci-s-alkoxycarbonylamino, straight- chain Co-8-alkylcarbonylamino, optionally N-mono- or N,N-di-Ci-8-alkylated amino or hydroxy or straight-chain omega-hydroxy-Ci-s-alkyl.
  • straight-chain Ci-s-alkanoyloxy is straight-chain Co-7-alkylcarbonyloxy such as formyloxy, acetyloxy, propionyloxy and butyryloxy.
  • straight-chain Ci- 8 -alkyl are methyl, ethyl, n-propyl, n-butyl, n-pentyl and n-hexyl respectively.
  • Examples of straight-chain omega-hydroxy-Ci-s-alkyl are hydroxymethyl, 2-hydroxy- ethyl, 3-hydroxy-n-propyl, 4-hydroxy-n-butyl, 5-hydroxy-n-pentyl and 6-hydroxy-n-hexyl respectively.
  • Examples of straight-chain Ci-s-alkoxy are radicals such as methoxy, ethoxy, n-propoxy and n-butoxy.
  • Examples of straight-chain Co-Cs-alkylcarbonylamino are for example formylamino (formamido), acetylamino, propionylamino and butylcarbonylamino.
  • N-mono- or N,N-di-Ci-8-alkylated amino is preferably optionally N-mono- or N,N-di-straight-chain-Ci-8-alkylated amino and may, for example, be amino, methylamino, dimethylamino, ethylamino, methylethylamino, n-propylamino, n-butylamino, n-pentylamino or n-hexylamino.
  • the compounds of the formula (I) have at least three asymmetric carbon atoms and may therefore exist in the form of optically pure diastereomers, mixtures of diastereomers, diastereomehc racemates, mixtures of diastereomeric racemates or as meso compounds.
  • the invention encompasses all these forms.
  • Mixtures of diastereomers, diastereomeric racemates or mixtures of diastereomeric racemates can be fractionated by conventional methods, e.g. by column chromatography, thin-layer chromatography, HPLC and the like.
  • Salts are primarily the pharmaceutically acceptable or nontoxic salts of compounds of formula (I).
  • pharmaceutically acceptable salts encompasses salts with inorganic or organic acids, such as hydrochloric acid, hydrobromic acid, nitric acid, sulfuric acid, phosphoric acid, citric acid, formic acid, maleic acid, acetic acid, succinic acid, tartaric acid, methanesulfonic acid, p-toluenesulfonic acid and the like.
  • Salts of compounds having salt-forming groups are in particular acid addition salts, salts with bases, or, in the presence of a plurality of salt-forming groups, in some cases also mixed salts or internal salts.
  • Such salts are formed, for example, from compounds of formula (I) with an acidic group, for example a carboxyl or sulfonyl group, and are, for example, the salts thereof with suitable bases such as non-toxic metal salts derived from metals of group Ia, Ib, Ha and Hb of the Periodic Table of the Elements, for example alkali metal, in particular lithium, sodium, or potassium, salts, alkaline earth metal salts, for example magnesium or calcium salts, and also zinc salts and ammonium salts, including those salts which are formed with organic amines, such as optionally hydroxy-substituted mono-, di- or trialkylamines, in particular mono-, di- or tri(lower alkyl)amines, or with quaternary ammonium bases, e.g.
  • suitable bases such as non-toxic metal salts derived from metals of group Ia, Ib, Ha and Hb of the Periodic Table of the Elements, for example alkali metal, in particular
  • methyl-, ethyl-, diethyl- or triethylamine mono-, bis- or tris(2-hydroxy(lower alkyl))amines, such as ethanol-, diethanol- or triethanolamine, tris(hydroxymethyl)methylamine or 2-hydroxy-tert- butylamine, N,N-di(lower alkyl)-N-(hydroxy(lower alkyl))amine, such as N,N-di-N- dimethyl-N-(2-hydroxyethyl)amine, or N-methyl-D-glucamine, or quaternary ammonium hydroxides such as tetrabutyl ammoniumhydroxide.
  • the compounds of formula (I) having a basic group, for example an amino group may form acid addition salts, for example with suitable inorganic acids, e.g. hydrohalic acid such as hydrochloric acid, hydrobromic acid, sulfuric acid with replacement of one or both protons, phosphoric acid with replacement of one or more protons, e.g. ortho- phosphoric acid or metaphosphohc acid, or pyrophosphohc acid with replacement of one or more protons, or with organic carboxylic, sulfonic or phosphonic acids or N-substituted sulfamic acids, e.g.
  • suitable inorganic acids e.g. hydrohalic acid such as hydrochloric acid, hydrobromic acid, sulfuric acid with replacement of one or both protons, phosphoric acid with replacement of one or more protons, e.g. ortho- phosphoric acid or metaphosphohc acid, or pyrophosphohc acid with replacement of one or more protons, or with organic carboxylic, sulf
  • Salts obtained may be converted to other salts in a manner known per se, acid addition salts, for example, by treating with a suitable metal salt such as a sodium, barium or silver salt, of another acid in a suitable solvent in which an inorganic salt which forms is insoluble and thus separates out of the reaction equilibrium, and base salts by release of the free acid and salt reformation.
  • a suitable metal salt such as a sodium, barium or silver salt
  • the compounds of formula (I), including their salts may also be obtained in the form of hydrates or include the solvent used for the crystallization.
  • Prodrug derivatives of the compounds described herein are derivatives thereof which on in vivo use liberate the original compound by a chemical or physiological process.
  • a prodrug may for example be converted into the original compound when a physiological pH is reached or by enzymatic conversion.
  • Possible examples of prodrug derivatives are esters of freely available carboxylic acids, S- and O-acyl derivatives of thiols, alcohols or phenols, the acyl group being defined as herein.
  • Preferred derivatives are pharmaceutically acceptable ester derivatives which are converted by solvolysis in physiological medium into the original carboxylic acid, such as, for example, lower alkyl esters, cycloalkyl esters, lower alkenyl esters, benzyl esters, mono- or disubstituted lower alkyl esters such as lower omega-(amino, mono- or dialkylamino, carboxy, lower alkoxycarbonyl) - alkyl esters or such as lower alpha-(alkanoyloxy, alkoxycarbonyl or dialkylaminocarbonyl) - alkyl esters; conventionally, pivaloyloxymethyl esters and similar esters are used as such.
  • lower alkyl esters such as, for example, lower alkyl esters, cycloalkyl esters, lower alkenyl esters, benzyl esters, mono- or disubstituted lower alkyl esters such as lower omega-(amino, mono- or dial
  • a particular compound in this invention also includes its prodrug derivative and salt form, where this is possible and appropriate.
  • the definitions mentioned apply within the scope of general chemical principles such as, for example, the usual valencies of atoms.
  • the compounds of the formula (I) also include those compounds in which one or more atoms are replaced by their stable, non-radioactive isotopes; for example, a hydrogen atom by deuterium.
  • a preferred group of compounds of the formula (I) and the pharmaceutically acceptable salts thereof are compounds in which R 1 is hydroxy or straight-chain onnega-hydroxy-Ci-s-alkyl, more preferably hydroxy or straight-chain omega-hydroxy-Ci -4 -alkyl.
  • a further preferred group of compounds of the formula (I) and the pharmaceutically acceptable salts thereof, are compounds in which
  • R 1 is straight-chain Ci-s-alkoxy or straight-chain Ci-s-alkoxy-straight-chain-Ci-s- alkoxy, more preferably straight-chain Ci -4 -alkoxy or straight-chain Ci -4 -alkoxy- straight-chain-Ci -4 -alkoxy.
  • a further preferred group of compounds of the formula (I) and the pharmaceutically acceptable salts thereof, are compounds in which
  • R 1 is straight-chain Ci-s-alkanoyloxy, more preferably straight-chain Ci -4 -alkanoyloxy.
  • a further preferred group of compounds of the formula (I) and the pharmaceutically acceptable salts thereof, are compounds in which
  • R 1 is straight-chain Co-8-alkylcarbonylamino, more preferably straight-chain C0-3- alkylcarbonylamino.
  • a further preferred group of compounds of the formula (I) and the pharmaceutically acceptable salts thereof, are compounds in which
  • R 1 is optionally N-mono- or N,N-di-Ci-8-alkylated amino, more preferably optionally N- mono- or N,N-di-Ci -4 -alkylated amino,.
  • a further preferred group of compounds of the formula (I) and the pharmaceutically acceptable salts thereof, are compounds in which
  • R 1 is optionally N-mono- or N,N-di-straight-chain-Ci-8-alkylated amino, more preferably optionally N-mono- or N,N-di-straight-chain-Ci -4 -alkylated amino.
  • R 1 is very particularly preferably hydroxy, methoxy, 2-methoxy-ethoxy, acetyloxy formamido, methylcarbonylamino or ethylcarbonylamino.
  • the compound groups mentioned above are not to be regarded as closed, but rather parts of these compound groups may be exchanged with one another or with the definitions given above or omitted in a sensible manner, for example to replace general by more specific definitions.
  • the definitions are valid in accordance with general chemical principles, such as, for example, the common valences for atoms.
  • the compounds of formula (I) can be prepared in an analogous manner to preparation processes disclosed in the literature. Similar preparation processes are described for example in WO 97/09311. Details of the specific preparation variants can be found in the examples.
  • the compounds of formula (I) may also be prepared in optically pure form.
  • the separation into antipodes can be effected by procedures known per se, either preferably at an earlier synthetic stage by salt formation with an optically active acid, for example (+)- or (-)-mandelic acid and separation of the diastereomehc salts by fractional crystallization, or preferably at a relatively late stage by dehvatizing with a chiral auxiliary building block, for example (+)- or (-)-camphanoyl chloride, and separation of the diastereomeric products by chromatography and/or crystallization and subsequent cleavage of the bonds to give the chiral auxiliary.
  • the pure diastereomeric salts and derivatives may be analysed to determine the absolute configuration of the pipehdine present with common spectroscopic procedures, and X-ray spectroscopy on single crystals constitutes a particularly suitable procedure.
  • the compounds of formula (I), and their pharmaceutically acceptable salts reveal inhibitory activities on the enzymes beta-secretase, cathepsin D, plasmepsin Il and/or HIV-protease.
  • the activitiy of inhibitors of beta-secretase, cathepsin D, plasmepsin Il and/or HIV protease can be assessed experimentally with following in vitro assays.
  • the protease inhibitory activity of compounds can be tested with an assay kit using the fluorescence resonance energy transfer (FRET) technology and a recombinant i.e. baculovirus expressed enzyme preparation.
  • FRET fluorescence resonance energy transfer
  • the FRET is used to monitor the cleavage of the peptide substrate.
  • the principle of the assay is as follows relies on a measurable energy difference, quantitatively depending on the presence of a peptide sequence.
  • the peptide substrate is synthesized with two terminal fluorophores, a fluorescent donor and quenching acceptor.
  • the distance between these two groups is selected so that upon light excitation, the donor fluorescence energy is significantly quenched by the acceptor through resonance energy transfer. Upon cleavage by the protease, the fluorophore is separated from the quenching group, restoring the fluorescence yield of the donor.
  • a weakly fluorescent peptide substrate becomes highly fluorescent upon enzymatic cleavage; the increase in fluorescence is linearly related to the rate of proteolysis.
  • the FRET assay was performed in white polysorp plates.
  • the assay buffer consisted of 50 mM sodium acetate pH 5, 392 mM sodium chloride, 12.5% glycerol and 0.1 % BSA.
  • the incubates per well were composed of 160 ⁇ l buffer, 10 ⁇ l inhibitor in DMSO, 10 ⁇ l peptide substrate in DMSO and 20 ⁇ l enzyme-solution. The inhibitors are tested in a concentration range of 1 pM to 1 mM.
  • the fluorescently marked donor and acceptor peptide substrates are generated by solid phase peptide synthesis (Applied Biosystems).
  • the beta-secretase peptide substrate Rh-GIu-VaI- Asn-Leu-Asp-Ala-Glu-Phe-Lys-Quencher is obtained from Invitrogen, Carlsbad, CA, USA.
  • the cathepsin D peptide substrate of the sequence DABCYL-Pro-Thr-Glu- Phe-Phe-Arg-Leu-OXL, the plasmepsin peptide substrate of the sequence DABCYL- Glu-Arg-Nle-Phe-Leu-Ser-Phe-Pro-OXL and the HIV protease peptide substrate of the sequence DABCYL-His-Lys-Ala-Arg-Val-Leu-Tyr-Glu-Ala-Nle-Ser-EDANS are all obtained from AnaSpec Inc, San Jose, CA, USA.
  • the recombinantly expressed enzyme preparations are added in various amounts to the assay systems eg the beta-sectrase concentration is 1 unit/ml incubation volume, the cathepsin D concentration is 100 ng/ml, the HIV protease concentration is 500 ng/ml and the plasmepsin Il concentration is 50 ng/ml.
  • the reaction is started upon addition of the enzyme solution. The incubation occurs at 37°C over 30-120 min ie specifically the beta-secretase incubation lasts 60 min, the cathepsin D incubation 120 min, the plasmepsin Il incubation 40 min and the HIV protease incubation 40 min.
  • the reactions are stopped by the addition of 20 ⁇ l of a 1.0 M Tris Base solution.
  • the enzymatic substrate to product conversion is assessed by fluorescence measurements at 460 nm wave length.
  • the compounds of the present invention revealed structure-dependent and enzyme- specific inhibitory activities.
  • the inhibitory activities were measured as IC50 values.
  • the beta-secretase inhibitory activity ranged between 1 pM and 1 mM;
  • the values for cathepsin D ranged between 1 pM and 1 mM, for plasmepsin Il between 1 pM and 1 mM and for HIV-protease between 1 pM and 1 mM.
  • the compounds of the formula (I) and the pharmaceutically acceptable salts thereof may find use as medicines, for example in the form of pharmaceutical preparations.
  • the pharmaceutical preparations may be administered enterally, such as orally, for example in the form of tablets, coated tablets, sugar-coated tablets, hard and soft gelatine capsules, solutions, emulsions or suspensions, nasally, for example in the form of nasal sprays, rectally, for example in the form of suppositories, or trans- dermally, for example in the form of ointments or patches.
  • the administration may also be parenteral, such as intramuscular or intravenous, for example in the form of injection solutions.
  • the compounds of the formula (I) and pharmaceutically usable salts thereof may be processed with pharmaceutically inert, inorganic or organic excipients.
  • excipients used for example for tablets, coated tablets and hard gelatine capsules, may be lactose, corn starch, or derivatives thereof, talc, stearic acid or salts thereof etc.
  • Suitable excipients for soft gelatine capsules are, for example, vegetable oils, waxes, fats, semisolid and liquid polyols, etc.
  • Suitable excipients for preparing solutions and syrups are, for example, water, polyols, sucrose, invert sugar, glucose, etc.
  • Suitable excipients for injection solutions are, for example, water, alcohols, polyols, glycerol, vegetable oils, bile acids, lecithin, etc.
  • Suitable excipients for suppositories are, for example, natural or hardened oils, waxes, fats, semisolid or liquid polyols, etc.
  • the pharmaceutical preparations may additionally also comprise preservatives, solubilizers, viscosity-increasing substances, stabilizers, wetting agents, emulsifiers, sweeteners, colorants, flavourings, salts for altering the osmotic pressure, buffers, coatings or antioxidants. They may also comprise other therapeutically valuable substances.
  • Subject of the present invention is also the use of the compounds of formula (I), and their pharmaceutically acceptable salts for the prevention, delay of progression or the treatment of Alzheimer Disease, malaria or HIV infection.
  • Subject of the present invention is also the use of the compounds of formula (I), and their pharmaceutically acceptable salts for the manufacture of a medication for the prevention, delay of progression or the treatment of Alzheimer Disease, malaria or HIV infection.
  • Subject of the present invention is also the method for the prevention, delay of progression or the treatment of Alzheimer Disease, malaria or HIV infection, whereby a therapeutically effective dose of a compound of the general formula (I) or a pharmaceutically acceptable salt thereof is applied.
  • Subject of the present invention is also a pharmaceutical preparation that contains for the inhibition of beta-secretase, cathepsin D, plasmepsin and/or HIV-protease a compound of the general formula (I), or a pharmaceutically acceptable salt thereof as well as commonly used ingredients.
  • Subject of the present invention is also a pharmaceutical preparation for the prevention, delay of progression or treatment of Alzheimer Disease, malaria and HIV infection that contains a compound of the general formula (I), or a pharmaceutically acceptable salt thereof as well as commonly used ingredients.
  • the dose may vary within wide limits and has of course to be adapted to the individual circumstances in each individual case.
  • the reaction mixture is quenched by addition of 10 ml of methanol and concentrated under reduced pressure.
  • the title compound is obtained from the residue by means of flash chromatography (SiO 2 60F).
  • the starting material(s) is(are) prepared as follows: a) (3S,4R,5R)-3-Hvdroxymethyl-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)- phenyl1-5-r4-(3-methoxy-propyl)-3,4-dihvdro-2H-benzo ⁇ ,41oxazin-6-ylmethoxy1- piperidine-1 -carboxylic acid benzyl ester
  • reaction mixture After overnight stirring, the reaction mixture is cooled to 10 0 C and successively treated dropwise with a solution of 251.871 mmol of potassium hydroxide in 60 ml of water and then with 86.852 mmol of hydrogen peroxide (30%/water). The reaction mixture is slowly warmed to 65°C, stirred for 3 hours and then re-cooled to room temperature. The reaction mixture is partitioned between tert-butyl methyl ether and ice-water - the organic layer is washed with brine. The combined aqueous layers are extracted with tert-butyl methyl ether (2X) - the combined organic layers are dried with sodium sulfate and evaporated.
  • reaction mixture After 2 hours, the reaction mixture is cooled to room temperature and then a solution of 125.214 mmol of 1 -benzyl-3-thtyloxymethyl- piperidin-4-one [234757-27-8] in 170 ml of tetrahydrofuran is slowly added, taking care to keep the internal reaction temperature under 40°C. After overnight stirring at room temperature, the reaction mixture is quenched with saturated aqueous ammonium chloride solution. Ethyl acetate is added to the reaction mixture and the phases separated - the organic phase is washed successively with water and brine. The combined aqueous phases are back-extracted with ethyl acetate - the combined organic phases are dried with sodium sulfate and evaporated.
  • thisopropyl-(3-methoxy-2(S)-methylpropoxy)silane is used to afford the title compound as a yellow oil.
  • Rf 0.42 (dichloromethane- diethylether 1 :1 ).
  • the starting material(s) is(are) prepared as follows: a) (3R,4R,5R)-3-(Acetylamino-methyl)-4-[4-((S)-3-methoxy-2-methyl- propoxymethyl)-phenvH-5-[4-(3-methoxy-propyl)-3,4-dihvdro-2H- benzo[1 ,41oxazin-6-ylmethoxy1-piperidine-1 -carboxylic acid benzyl ester 5.936 mmol of acetyl chloride are added to a solution of 5.396 mmol of (3R,4R,5R)-3- aminomethyl-4-[4-((S)-3-methoxy-2-methyl-propoxymethyl)-phenyl]-5-[4-(3-methoxy- propyl)-3,4-dihydro-2H-benzo[1 ,4]oxazin-6-ylmethoxy]-piperidine-1 -car
  • the starting material(s) is(are) prepared as follows: a) (3S,4R,5R)-3-Methoxymethyl-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)- phenyl1-5-r4-(3-methoxy-propyl)-3,4-dihvdro-2H-benzo ⁇ ,41oxazin-6-ylmethoxy1- piperidine-1 -carboxylic acid benzyl ester
  • the starting material(s) is(are) prepared as follows: a) (3S,4R,5R)-3-Acetoxymethyl-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)- phenyl1-5-r4-(3-methoxy-propyl)-3,4-dihvdro-2H-benzo ⁇ ,41oxazin-6-ylmethoxy1- piperidine-1 -carboxylic acid benzyl ester

Landscapes

  • Health & Medical Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Veterinary Medicine (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Public Health (AREA)
  • Medicinal Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Tropical Medicine & Parasitology (AREA)
  • Engineering & Computer Science (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Biomedical Technology (AREA)
  • Neurosurgery (AREA)
  • Virology (AREA)
  • Neurology (AREA)
  • Molecular Biology (AREA)
  • Oncology (AREA)
  • Hospice & Palliative Care (AREA)
  • Communicable Diseases (AREA)
  • AIDS & HIV (AREA)
  • Psychiatry (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Hydrogenated Pyridines (AREA)
  • Plural Heterocyclic Compounds (AREA)

Abstract

Described are compounds of the general formula (I), and pharmaceutically acceptable salt thereof, in which R1 has the definitions illustrated in detail in the description, as beta-secretase, cathepsin D, plasmepsin II and/or HIV protease inhibitors.

Description

Substituted piperidines as therapeutic compounds
Field of the Invention
The present invention relates to the use of substituted piperidines as beta-secretase-, cathepsin D-, plasmepsin II- and/or HIV-protease-inhibitors.
Background of the Invention
With regard to beta-secretase-, cathepsin D-, plasmepsin II- and/or HlV-protease- inhibition, there is still a need for highly potent active ingredients. In this context, the improvement of the pharmacokinetic properties is at the forefront. These properties directed towards better bioavailability are, for example, absorption, metabolic stability, solubility or lipophilicity.
Alzheimer Disease aspartyl protease: Beta-Secretase
Alzheimer's disease (AD) is a progressive degenerative disease of the brain. The symptoms of AD include progressive memory loss, language difficulty and ultimately loss of basic neural function and death. The biomarkers in the central nervous system for AD include amyloid plaques, intracellular neurofibrillary tangles and activated microglia. The appearance of these three markers is likely to contribute to the neuronal cell death and memory loss observed in AD.
Beta-amyloid is a defining feature of AD and now believed to be a causative precursor in the development of the disease. Amyloidogenic plaques and vascular amyloid angiopathy also characterize the brains of individuals with Trisomy 21 (Down's Syndrome), Hereditary Cerebral Hemorrhage with Amloidosis of the Dutch-Type (HCHWA-D) and other neurodegenerative disorders.
Beta-amyloid plaques are predominantly composed of amyloid beta peptide (A-beta, also sometimes designated betaA4). The A-beta peptide is derived by proteolysis of the beta amyloid precursor protein (APP). Beta-APP is processed by three distinct ordered enzymatic activities. The bulk of beta-APP is processed via alpha-secretase in a non-amyloidogenic pathway. A small fraction of beta-APP is cleaved by beta- secretase activity to generate the membrane-bound C-terminal fragment C99. Gamma-secretase cleaves C99 to generate the amyloidogenic A-beta peptide of 39-42 amino acids. The aspartyl protease activity of beta-secretase has been disclosed using varied nomenclature, including BACE (beta-site APP cleaving enzyme), Asp and memapsin.
The significance of beta-secretase cleavage of beta-APP as a critical step in the generation of AD is underscored by the observation that human mutations at the beta-secretase cleavage subsites (Swedish mutations) of beta-APP lead to increased A-beta production and early onset familial AD. Furthermore, BACE1 - knockout mice fail to produce A-beta peptide and present a normal phenotype. When crossed with transgenic mice that overexpress APP, the progeny show reduced amounts of A-beta in brain extracts as compared with control animals. This evidence supports the proposal that inhibition of beta-secretase activity and reduction of A-beta peptide deposits in the brain provides a therapeutic strategy for the treatment of AD and other beta amyloid disorders as described by Verdile et al. (2004) in Pharmacol. Res 50, 397-409.
Compounds that are effective inhibitors of beta-secretase may inhibit beta-secretase- mediated cleavage of APP and the production of A-beta peptide. The pharmacological inhibition of A-beta peptide generation may reduce amyloid beta deposits, respectively the formation of plaques. Beta-secretase inhibiting compounds as discussed by Thompson et al. (2005) in Curr. Pharm. Des. 11 , 3383-3404 are therefore useful to treat or to prevent diseases that are characterized by amyloid beta deposits or plaques such as AD.
The present invention also relates to methods of treating subjects who have, or in preventing subjects from developing a disease or condition selected from the group consisting of AD, for helping prevent or delay the onset of AD, for helping to slow the proression of AD, for treating subjects with mild cognitive impairment (MCI) and preventing or delaying the onset of AD in those who could progress form MCI to AD, for treating Down's syndrome, for treating humans who have HCHWAD, for treating cerebral amyloid angiopathy, and for treating degenerative dementias Alzheimer's Disease aspartyl protease: Cathepsin D
Human cathepsin D is an intracellular aspartic peptidase found mainly in lysosomes. It has a number of housekeeping functions, including the degradation of cellular and phagocytosed proteins. The enzymes may be involved in a variety of disease states, including cancer and Alzheimer's disease (AD). Clinical studies have shown that cathepsin D is overexpressed in breast cancer cells and this seems to be associated with an increased risk for metastasis due to enhanced cell growth. Cathepisn D is also thought to be involved in formation of the beta-amyloid peptide in AD. Recently, several genetic association studies linked cathepsin D with amyloid pathology and Alzheimer's disease as described for example by Davidson et al., (2006) in J. Neurol. Neurosurg. Psychiatry 77, 515-517. The availability of selective and potent inhibitors will help to further define the role of cathepsin D in disease and possibly lead to therapeutic agents.
Malaria Aspartyl Protease: Plasmepsin I and Il
Malaria is considered as one of the most serious infectious diseases in the world, affecting approximately 500 million people. The disease is spread by the anopheles mosquito that is mostly found in tropical regions. The species Plasmodium falciparum is responsible for more than 95% of malaria-related morbidity and mortality. Increasingly, Plasmodium falciparum is becoming resistant to existing therapies such as chloroquine, mefloquine and sulfadoxime/ pyrimethamine. Thus there is an urgent need for new treatments.
In the erythrocytic stage of the parasite's life cycle the parasite invades the red blood cells of its host consuming up to 80% of the hemoglobin as a source of nutrients for growth and development. Hemoglobin degradation takes place in an acidic vacuole of the parasite and many of the current antimalarial drugs appear to disrupt important vacuolar functions. The food vacuole contains aspartic, cysteine and metallo- proteases, which are all considered to play a role in the process of hemoglobin degradation. At least 10 genes encoding aspartic proteases have been identified in the Plasmodium genome. Four of the aspartic proteases have been localized in the acidic food vacuole of the parasite, namely plasmepsin I, II, IV and HAP, a histo- aspartic protease. Inhibitors of plasmepsin I and Il have shown efficacy in cell and animal models of malaria, indicating that these enzymes may represent targets for drug discovery as described for example by Coombs et al. (2001 ) Trends Parasitol 17, 532-537. Indeed, a non-selective inhibitor of aspartic proteases, pepstatin, inhibits the growth of Plasmodium falciparum in vitro. Similar results have been obtained with analogs of pepstatin or with immunodeficiency virus protease inhibitors indicating that inhibition of aspartic proteases interferes with the life cycle of Plasmodium falciparum as noted for example by Andrews et al. (2006) in Antimicrob. Agents Chemother 50, 639-648.
The present invention relates to the identification of low molecular weight, non- peptidic inhibitors of the Plasmodium falciparum protease plasmepsin Il or other related aspartic proteases to treat and/or to prevent malaria.
HIV aspartyl protease: HIV-1 peptidase
First reported in 1981 in a small number of patients, Acquired immunodeficiency syndrome (AIDS) has now become a major epidemic with more than 38 million people infected worldwide, including approximately 1 million in the United States, 580,000 in Western Europe and more than 25 million in Sub-Saharan Africa (http://www.unaids.org). Since AIDS was first clinically identified, scientific and therapeutic progress has been extraordinary. However, AIDS remains out of control, especially in developing countries.
The prognosis of AIDS patients who have full access to current therapies has completely changed since the first cases of AIDS were reported. Today, the median survival for HIV-positive patients receiving treatment exceeds 8 years. The life expectancy for AIDS patients was less than 1 year before AZT was introduced in 1987. This dramatic change is due to the development of effective therapies, to early detection of HIV-positive individuals, and to a sustained effort to analyze and understand viral-resistance mechanisms, which can be overcome by rational drug development and combination therapy. FDA-approved therapies target three steps of the HIV life cycle: reverse transcription, proteolytic maturation and fusion. Triple therapy, commonly referred to as HIGHLY ACTIVE ANTIRETROVIRAL THERAPY (HAART), is now the standard for treatment. It consists of a protease inhibitor or a non-nucleoside reverse transcriptase inhibitor in combination with two nucleoside reverse transcriptase inhibitors.
Translation of human immunodeficiency virus type-1 (HIV-1 ) genomic RNA results in the production of two polyprotein precursors, Gag and Gag-Pol. The 55-kDa Gag precursor contains the structural proteins and the 160-kDa Gag-Pol polyprotein contains the functional viral enzymes protease, reverse transcriptase, and integrase. Gag and Gag-Pol polyproteins are transported to the plasma membrane where assembly of type-C retroviruses and lentiviruses typically occurs. During particle assembly, the viral protease cleaves the Gag and Gag-Pol precursors into the structural and functional proteins required for viral replication. The protease activity within the cytoplasma of infected cells allows for the formation of virions which can be released from the cell in the last stages of budding.
The mature HIV-1 protease is an obligatory dimer of identical 11 -kDa subunits, each contributing one of the two catalytic aspartic residues. In contrast, the cell-derived members of the aspartic protease family are monomehc enzymes with two Asp-Thr- Gly-containing domains. The unique dimeric structure of the retroviral protease is mainly stabilized by an antiparallel beta-sheet formed by the interdigitation of the amino- and carboxyl-terminal beta-strands of each monomer.
The activation of HIV-1 protease i.e. the dimerization and autocatalytic release from Gag-Pol, is a critical step in the viral life cycle. Inhibition of protease activation causes a severe defect in Gag polyprotein processing and a complete loss of viral infectivity. As such, the viral protease has become a target for HIV therapeutics, resulting in many HIV protease inhibitors reaching clinical trials as reviewed by Rana et al. (1999) in Pharmacotherapy 19, 35-59 and Morse et al., (2006) in Lancet Infect. Dis. 6, 215-225. Most of these drugs are substrate-based inhibitors, whose design has been facilitated by an abundance of crystal structure data for both the native enzyme and enzyme- inhibitor complexes. Additionally, there are now extensive biochemical data detailing both the catalytic mechanism and the molecular basis for substrate selection. Detailed Description of the Invention
Firstly, the present invention relates to compounds of the general formula
(I) for the inhibition of beta-secretase, cathepsin D, plasmepsin Il and/or HIV-protease and their pharmaceutically acceptable salts, in which
R1 is straight-chain Ci-s-alkanoyloxy, straight-chain Ci-s-alkoxy, straight-chain Ci-S- alkoxy-straight-chain-Ci-s-alkoxy, straight-chain Ci-s-alkoxycarbonylamino, straight- chain Co-8-alkylcarbonylamino, optionally N-mono- or N,N-di-Ci-8-alkylated amino or hydroxy or straight-chain omega-hydroxy-Ci-s-alkyl.
A straight-chain is also sometimes referred to in the literature as linear or un-branched. As used herein, straight-chain Ci-s-alkanoyloxy is straight-chain Co-7-alkylcarbonyloxy such as formyloxy, acetyloxy, propionyloxy and butyryloxy. Examples of straight-chain Ci-8-alkyl are methyl, ethyl, n-propyl, n-butyl, n-pentyl and n-hexyl respectively. Examples of straight-chain omega-hydroxy-Ci-s-alkyl are hydroxymethyl, 2-hydroxy- ethyl, 3-hydroxy-n-propyl, 4-hydroxy-n-butyl, 5-hydroxy-n-pentyl and 6-hydroxy-n-hexyl respectively. Examples of straight-chain Ci-s-alkoxy are radicals such as methoxy, ethoxy, n-propoxy and n-butoxy. Examples of straight-chain Co-Cs-alkylcarbonylamino are for example formylamino (formamido), acetylamino, propionylamino and butylcarbonylamino. Optionally N-mono- or N,N-di-Ci-8-alkylated amino is preferably optionally N-mono- or N,N-di-straight-chain-Ci-8-alkylated amino and may, for example, be amino, methylamino, dimethylamino, ethylamino, methylethylamino, n-propylamino, n-butylamino, n-pentylamino or n-hexylamino.
The compounds of the formula (I) have at least three asymmetric carbon atoms and may therefore exist in the form of optically pure diastereomers, mixtures of diastereomers, diastereomehc racemates, mixtures of diastereomeric racemates or as meso compounds. The invention encompasses all these forms.
Mixtures of diastereomers, diastereomeric racemates or mixtures of diastereomeric racemates can be fractionated by conventional methods, e.g. by column chromatography, thin-layer chromatography, HPLC and the like.
Salts are primarily the pharmaceutically acceptable or nontoxic salts of compounds of formula (I). The term "pharmaceutically acceptable salts" encompasses salts with inorganic or organic acids, such as hydrochloric acid, hydrobromic acid, nitric acid, sulfuric acid, phosphoric acid, citric acid, formic acid, maleic acid, acetic acid, succinic acid, tartaric acid, methanesulfonic acid, p-toluenesulfonic acid and the like.
Salts of compounds having salt-forming groups are in particular acid addition salts, salts with bases, or, in the presence of a plurality of salt-forming groups, in some cases also mixed salts or internal salts.
Such salts are formed, for example, from compounds of formula (I) with an acidic group, for example a carboxyl or sulfonyl group, and are, for example, the salts thereof with suitable bases such as non-toxic metal salts derived from metals of group Ia, Ib, Ha and Hb of the Periodic Table of the Elements, for example alkali metal, in particular lithium, sodium, or potassium, salts, alkaline earth metal salts, for example magnesium or calcium salts, and also zinc salts and ammonium salts, including those salts which are formed with organic amines, such as optionally hydroxy-substituted mono-, di- or trialkylamines, in particular mono-, di- or tri(lower alkyl)amines, or with quaternary ammonium bases, e.g. methyl-, ethyl-, diethyl- or triethylamine, mono-, bis- or tris(2-hydroxy(lower alkyl))amines, such as ethanol-, diethanol- or triethanolamine, tris(hydroxymethyl)methylamine or 2-hydroxy-tert- butylamine, N,N-di(lower alkyl)-N-(hydroxy(lower alkyl))amine, such as N,N-di-N- dimethyl-N-(2-hydroxyethyl)amine, or N-methyl-D-glucamine, or quaternary ammonium hydroxides such as tetrabutyl ammoniumhydroxide. The compounds of formula (I) having a basic group, for example an amino group, may form acid addition salts, for example with suitable inorganic acids, e.g. hydrohalic acid such as hydrochloric acid, hydrobromic acid, sulfuric acid with replacement of one or both protons, phosphoric acid with replacement of one or more protons, e.g. ortho- phosphoric acid or metaphosphohc acid, or pyrophosphohc acid with replacement of one or more protons, or with organic carboxylic, sulfonic or phosphonic acids or N-substituted sulfamic acids, e.g. acetic acid, propionic acid, glycolic acid, succinic acid, maleic acid, hydroxymaleic acid, methylmaleic acid, fumaric acid, malic acid, tartaric acid, gluconic acid, glucaric acid, glucuronic acid, citric acid, benzoic acid, cinnamic acid, mandelic acid, salicylic acid, 4-aminosalicylic acid, 2-phenoxybenzoic acid, 2-acetoxybenzoic acid, embonic acid, nicotinic acid, isonicotinic acid, and also amino acids, for example the alpha-amino acids mentioned above, and also methanesulfonic acid, ethanesulfonic acid, 2-hydroxyethanesulfonic acid, ethane-1 ,2- disulfonic acid, benzenesulfonic acid, 4-methylbenzenesulfonic acid, naphthalene-2- sulfonic acid, 2- or 3-phosphoglycerate, glucose 6-phosphate, N-cyclohexylsulfamic acid (with formation of the cyclamates) or with other acidic organic compounds such as ascorbic acid. Compounds of formula (I) having acidic and basic groups may also form internal salts.
Salts obtained may be converted to other salts in a manner known per se, acid addition salts, for example, by treating with a suitable metal salt such as a sodium, barium or silver salt, of another acid in a suitable solvent in which an inorganic salt which forms is insoluble and thus separates out of the reaction equilibrium, and base salts by release of the free acid and salt reformation. The compounds of formula (I), including their salts, may also be obtained in the form of hydrates or include the solvent used for the crystallization.
Pharmaceutically unsuitable salts may also be used for isolation and purification.
Prodrug derivatives of the compounds described herein are derivatives thereof which on in vivo use liberate the original compound by a chemical or physiological process. A prodrug may for example be converted into the original compound when a physiological pH is reached or by enzymatic conversion. Possible examples of prodrug derivatives are esters of freely available carboxylic acids, S- and O-acyl derivatives of thiols, alcohols or phenols, the acyl group being defined as herein. Preferred derivatives are pharmaceutically acceptable ester derivatives which are converted by solvolysis in physiological medium into the original carboxylic acid, such as, for example, lower alkyl esters, cycloalkyl esters, lower alkenyl esters, benzyl esters, mono- or disubstituted lower alkyl esters such as lower omega-(amino, mono- or dialkylamino, carboxy, lower alkoxycarbonyl) - alkyl esters or such as lower alpha-(alkanoyloxy, alkoxycarbonyl or dialkylaminocarbonyl) - alkyl esters; conventionally, pivaloyloxymethyl esters and similar esters are used as such.
Because of the close relationship between a free compound, a prodrug derivative and a salt compound, a particular compound in this invention also includes its prodrug derivative and salt form, where this is possible and appropriate. The definitions mentioned apply within the scope of general chemical principles such as, for example, the usual valencies of atoms.
The compounds of the formula (I) also include those compounds in which one or more atoms are replaced by their stable, non-radioactive isotopes; for example, a hydrogen atom by deuterium.
A preferred group of compounds of the formula (I) and the pharmaceutically acceptable salts thereof, are compounds in which R1 is hydroxy or straight-chain onnega-hydroxy-Ci-s-alkyl, more preferably hydroxy or straight-chain omega-hydroxy-Ci-4-alkyl.
A further preferred group of compounds of the formula (I) and the pharmaceutically acceptable salts thereof, are compounds in which
R1 is straight-chain Ci-s-alkoxy or straight-chain Ci-s-alkoxy-straight-chain-Ci-s- alkoxy, more preferably straight-chain Ci-4-alkoxy or straight-chain Ci-4-alkoxy- straight-chain-Ci-4-alkoxy.
A further preferred group of compounds of the formula (I) and the pharmaceutically acceptable salts thereof, are compounds in which
R1 is straight-chain Ci-s-alkanoyloxy, more preferably straight-chain Ci-4-alkanoyloxy.
A further preferred group of compounds of the formula (I) and the pharmaceutically acceptable salts thereof, are compounds in which
R1 is straight-chain Co-8-alkylcarbonylamino, more preferably straight-chain C0-3- alkylcarbonylamino.
A further preferred group of compounds of the formula (I) and the pharmaceutically acceptable salts thereof, are compounds in which
R1 is optionally N-mono- or N,N-di-Ci-8-alkylated amino, more preferably optionally N- mono- or N,N-di-Ci-4-alkylated amino,.
A further preferred group of compounds of the formula (I) and the pharmaceutically acceptable salts thereof, are compounds in which
R1 is optionally N-mono- or N,N-di-straight-chain-Ci-8-alkylated amino, more preferably optionally N-mono- or N,N-di-straight-chain-Ci-4-alkylated amino.
R1 is very particularly preferably hydroxy, methoxy, 2-methoxy-ethoxy, acetyloxy formamido, methylcarbonylamino or ethylcarbonylamino. The compound groups mentioned above are not to be regarded as closed, but rather parts of these compound groups may be exchanged with one another or with the definitions given above or omitted in a sensible manner, for example to replace general by more specific definitions. The definitions are valid in accordance with general chemical principles, such as, for example, the common valences for atoms.
The compounds of formula (I) can be prepared in an analogous manner to preparation processes disclosed in the literature. Similar preparation processes are described for example in WO 97/09311. Details of the specific preparation variants can be found in the examples.
The compounds of formula (I) may also be prepared in optically pure form. The separation into antipodes can be effected by procedures known per se, either preferably at an earlier synthetic stage by salt formation with an optically active acid, for example (+)- or (-)-mandelic acid and separation of the diastereomehc salts by fractional crystallization, or preferably at a relatively late stage by dehvatizing with a chiral auxiliary building block, for example (+)- or (-)-camphanoyl chloride, and separation of the diastereomeric products by chromatography and/or crystallization and subsequent cleavage of the bonds to give the chiral auxiliary. The pure diastereomeric salts and derivatives may be analysed to determine the absolute configuration of the pipehdine present with common spectroscopic procedures, and X-ray spectroscopy on single crystals constitutes a particularly suitable procedure.
The compounds of formula (I), and their pharmaceutically acceptable salts reveal inhibitory activities on the enzymes beta-secretase, cathepsin D, plasmepsin Il and/or HIV-protease.
The activitiy of inhibitors of beta-secretase, cathepsin D, plasmepsin Il and/or HIV protease can be assessed experimentally with following in vitro assays. The protease inhibitory activity of compounds can be tested with an assay kit using the fluorescence resonance energy transfer (FRET) technology and a recombinant i.e. baculovirus expressed enzyme preparation. The FRET is used to monitor the cleavage of the peptide substrate. The principle of the assay is as follows relies on a measurable energy difference, quantitatively depending on the presence of a peptide sequence. The peptide substrate is synthesized with two terminal fluorophores, a fluorescent donor and quenching acceptor. The distance between these two groups is selected so that upon light excitation, the donor fluorescence energy is significantly quenched by the acceptor through resonance energy transfer. Upon cleavage by the protease, the fluorophore is separated from the quenching group, restoring the fluorescence yield of the donor. Thus a weakly fluorescent peptide substrate becomes highly fluorescent upon enzymatic cleavage; the increase in fluorescence is linearly related to the rate of proteolysis.
The FRET assay was performed in white polysorp plates. The assay buffer consisted of 50 mM sodium acetate pH 5, 392 mM sodium chloride, 12.5% glycerol and 0.1 % BSA. The incubates per well were composed of 160 μl buffer, 10 μl inhibitor in DMSO, 10 μl peptide substrate in DMSO and 20 μl enzyme-solution. The inhibitors are tested in a concentration range of 1 pM to 1 mM. The fluorescently marked donor and acceptor peptide substrates are generated by solid phase peptide synthesis (Applied Biosystems). The beta-secretase peptide substrate Rh-GIu-VaI- Asn-Leu-Asp-Ala-Glu-Phe-Lys-Quencher is obtained from Invitrogen, Carlsbad, CA, USA. The cathepsin D peptide substrate of the sequence DABCYL-Pro-Thr-Glu- Phe-Phe-Arg-Leu-OXL, the plasmepsin peptide substrate of the sequence DABCYL- Glu-Arg-Nle-Phe-Leu-Ser-Phe-Pro-OXL and the HIV protease peptide substrate of the sequence DABCYL-His-Lys-Ala-Arg-Val-Leu-Tyr-Glu-Ala-Nle-Ser-EDANS are all obtained from AnaSpec Inc, San Jose, CA, USA. The recombinantly expressed enzyme preparations are added in various amounts to the assay systems eg the beta-sectrase concentration is 1 unit/ml incubation volume, the cathepsin D concentration is 100 ng/ml, the HIV protease concentration is 500 ng/ml and the plasmepsin Il concentration is 50 ng/ml. The reaction is started upon addition of the enzyme solution. The incubation occurs at 37°C over 30-120 min ie specifically the beta-secretase incubation lasts 60 min, the cathepsin D incubation 120 min, the plasmepsin Il incubation 40 min and the HIV protease incubation 40 min. The reactions are stopped by the addition of 20 μl of a 1.0 M Tris Base solution. The enzymatic substrate to product conversion is assessed by fluorescence measurements at 460 nm wave length.
In vitro enzyme inhibitory activities
The compounds of the present invention revealed structure-dependent and enzyme- specific inhibitory activities. The inhibitory activities were measured as IC50 values. Thus the beta-secretase inhibitory activity ranged between 1 pM and 1 mM; the values for cathepsin D ranged between 1 pM and 1 mM, for plasmepsin Il between 1 pM and 1 mM and for HIV-protease between 1 pM and 1 mM.
The compounds of the formula (I) and the pharmaceutically acceptable salts thereof may find use as medicines, for example in the form of pharmaceutical preparations. The pharmaceutical preparations may be administered enterally, such as orally, for example in the form of tablets, coated tablets, sugar-coated tablets, hard and soft gelatine capsules, solutions, emulsions or suspensions, nasally, for example in the form of nasal sprays, rectally, for example in the form of suppositories, or trans- dermally, for example in the form of ointments or patches. The administration may also be parenteral, such as intramuscular or intravenous, for example in the form of injection solutions.
To prepare tablets, coated tablets, sugar-coated tablets and hard gelatine capsules, the compounds of the formula (I) and pharmaceutically usable salts thereof may be processed with pharmaceutically inert, inorganic or organic excipients. Such excipients used, for example for tablets, coated tablets and hard gelatine capsules, may be lactose, corn starch, or derivatives thereof, talc, stearic acid or salts thereof etc.
Suitable excipients for soft gelatine capsules are, for example, vegetable oils, waxes, fats, semisolid and liquid polyols, etc.
Suitable excipients for preparing solutions and syrups are, for example, water, polyols, sucrose, invert sugar, glucose, etc.
Suitable excipients for injection solutions are, for example, water, alcohols, polyols, glycerol, vegetable oils, bile acids, lecithin, etc.
Suitable excipients for suppositories are, for example, natural or hardened oils, waxes, fats, semisolid or liquid polyols, etc.
The pharmaceutical preparations may additionally also comprise preservatives, solubilizers, viscosity-increasing substances, stabilizers, wetting agents, emulsifiers, sweeteners, colorants, flavourings, salts for altering the osmotic pressure, buffers, coatings or antioxidants. They may also comprise other therapeutically valuable substances.
Subject of the present invention is also the use of the compounds of formula (I), and their pharmaceutically acceptable salts for the prevention, delay of progression or the treatment of Alzheimer Disease, malaria or HIV infection.
Subject of the present invention is also the use of the compounds of formula (I), and their pharmaceutically acceptable salts for the manufacture of a medication for the prevention, delay of progression or the treatment of Alzheimer Disease, malaria or HIV infection.
Subject of the present invention is also the method for the prevention, delay of progression or the treatment of Alzheimer Disease, malaria or HIV infection, whereby a therapeutically effective dose of a compound of the general formula (I) or a pharmaceutically acceptable salt thereof is applied.
Subject of the present invention is also a pharmaceutical preparation that contains for the inhibition of beta-secretase, cathepsin D, plasmepsin and/or HIV-protease a compound of the general formula (I), or a pharmaceutically acceptable salt thereof as well as commonly used ingredients. Subject of the present invention is also a pharmaceutical preparation for the prevention, delay of progression or treatment of Alzheimer Disease, malaria and HIV infection that contains a compound of the general formula (I), or a pharmaceutically acceptable salt thereof as well as commonly used ingredients.
The dose may vary within wide limits and has of course to be adapted to the individual circumstances in each individual case. In general, for oral administration, a daily dose of about 3 mg to about 3 g, preferably about 10 mg to about 1 g, for example about 300 mg, per adult (70 kg), divided into preferably 1-3 individual doses which may, for example, be of equal size, may be appropriate, although the upper limit specified may also be exceeded if this should be found to be appropriate; typically, children receive a lower dose according to their age and body weight.
Examples
The following examples illustrate the present invention. All temperatures are stated in degrees Celsius and pressures in mbar. Unless mentioned otherwise, the reactions take place at room temperature. The abbreviation "Rf = xx (A)" means for example that the Rf is found in solvent system A to be xx. The ratio of amounts of solvents to one another is always stated in parts by volume. Chemical names for final products and intermediates have been generated on the basis of the chemical structural formulae with the aid of the AutoNom 2000 (Automatic Nomenclature) program.
HPLC gradients on Hypersil BDS C-18 (5 urn); column: 4 x 125 mm
I 90% water*/10% acetonitrile* to 0% water7100% acetonitrile* in 5 minutes +
2.5 minutes (1.5 ml/min)
II 95% water75% acetonitrile* to 0% water7100% acetonitrile* in 40 minutes (0.8 ml/min)
* contains 0.1 % trifluoroacetic acid
The following abbreviations are used:
Rf ratio of distance migrated by a substance to the distance of the solvent front from the starting point in thin-layer chromatography Rt retention time of a substance in HPLC (in minutes) m.p. melting point (temperature)
Thin-film chromatography eluent systems: A dichloromethane-methanol-25% ammonia cone. = 200:20:1 B dichloromethane-methanol-25% ammonia cone. = 200:10:1 C dichloromethane-methanol-25% ammonia cone. = 200:30:1 D dichloromethane-methanol-25% ammonia cone. = 100:10:1
General procedure A: (N-Cbz-deprotection, N-(1 -phenyl-ethyl)-deprotection or N- benzyl-deprotection)
To a stirred solution of 1 mmol of "N-protected derivative" in 15 ml of tetrahydrofuran
(or methanol) are added 0.1 mmol Pd/C 10% and the reaction mixture is hydro- genated at room temperature. The reaction mixture is filtered and concentrated under reduced pressure. The residue is purified by flash chromatography (SiO2 60F) to afford the title compound.
General procedure B: (N-Tos-deprotection)
To a stirred solution of 0.09 mmol "tosylamide" in 10 ml of methanol are added 0.44 mmol sodium dihydrogenphosphate and 0.90 mmol of sodium amalgam (10% Na) at room temperature. The reaction mixture is stirred for 2-18 hours, diluted with water and extracted with ethyl acetate (3X). The organic phases are combined, washed with brine and dried over sodium sulfate. The solvent is concentrated under reduced pressure and the residue is purified by flash chromatography (SiO2 60F) to afford the title compound.
General procedure C: (Bhh-reduction)
To a stirred solution of 1 mmol of "lactam" in 3 ml of tetrahydrofuran is admixed with
2-4 mmol of borane tetrahydrofuran (1 M in tetrahydrofuran) and heated to 500C for
2-8 hours.
The reaction mixture is quenched by addition of 10 ml of methanol and concentrated under reduced pressure. The title compound is obtained from the residue by means of flash chromatography (SiO2 60F).
General procedure D: (O-alkylation I)
1.2 mmol mmol of sodium hydride (60% dispersion in oil) and 0.1 mmol of tetrabutyl- ammonium iodide are added to a solution of 1 mmol of "alcohol" and 1.1 mmol of "benzyl halide" in 2.0 ml of N,N-dimethylformamide while stirring at -100C. The reaction mixture is stirred at -10°C for 1 hour and at room temperature for 18 hours. The mixture is poured into 1 M aqueous sodium bicarbonate solution and extracted with tert-butyl methyl ether (2X). The organic phases are washed successively with water and brine, dried with sodium sulfate and evaporated. The title compound is obtained from the residue by means of flash chromatography (SiO2 60F).
General Method E: (O-alkylation II)
1.1 mmol of sodium hydride (60% dispersion in oil) are added to a solution of 1 mmol of "alcohol" and 1.0-2.0 mmol of "benzyl halide" in 2.0 ml of N,N-dimethylformamide while stirring at -100C. The reaction mixture is stirred at -10°C for 1 hour and at room temperature for 18 hours. The mixture is poured into 1 M aqueous sodium bicarbonate solution and extracted with tert-butyl methyl ether (2X). The combined organic phases are washed successively with water and brine, dried with sodium sulfate and evaporated. The title compound is obtained from the residue by flash chromatography (SiO2 60F). General Method F: (alcohol desilylation)
A solution of 1 mmol of "silyl ether" in 5 ml of tetrahydrofuran is mixed with
1.5-2.0 mmol of tetrabutylammonium fluoride (1 M solution in tetrahydrofuran) and the solution is stirred at room temperature for 1-2 hours. The reaction solution is then diluted with water and extracted with tert-butyl methyl ether (2X). The combined organic phases are dried with sodium sulfate and evaporated. The title compound is obtained from the residue by flash chromatography (SiO2 60F).
Example 1
{(3S,4R,5R)-4-r4-((S)-3-Methoxy-2-methyl-propoxymethyl)-phenyl1-5-r4-(3-methoxy- propyl)-3,4-dihvdro-2H-benzori ,41oxazin-6-ylmethoxy1-piperidin-3-yl)-methanol According to general procedure A, (3S,4R,5R)-3-hydroxymethyl-4-[4-((S)-3-methoxy- 2-methyl-propoxymethyl)-phenyl]-5-[4-(3-methoxy-propyl)-3,4-dihydro-2H- benzo[1 ,4]oxazin-6-ylmethoxy]-piperidine-1 -carboxylic acid benzyl ester is used to afford the title compound.
The starting material(s) is(are) prepared as follows: a) (3S,4R,5R)-3-Hvdroxymethyl-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)- phenyl1-5-r4-(3-methoxy-propyl)-3,4-dihvdro-2H-benzoπ ,41oxazin-6-ylmethoxy1- piperidine-1 -carboxylic acid benzyl ester
According to general procedure C, (3S,4R,5R)-3-hydroxymethyl-4-[4-((S)-3-methoxy- 2-methyl-propoxymethyl)-phenyl]-5-[4-(3-methoxy-propyl)-3-oxo-3,4-dihydro-2H- benzo[1 ,4]oxazin-6-ylmethoxy]-piperidine-1 -carboxylic acid benzyl ester is used to afford the title compound as a turbid oil. Rf = 0.15 (EtOAc-heptane 2:1 ); Rt = 5.22 (gradient I).
b) (3S,4R,5R)-3-Hvdroxymethyl-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)- phenvπ-5-[4-(3-methoxy-propyl)-3-oxo-3,4-dihvdro-2H-benzo[1 ,41oxazin-6- ylmethoxyi-piperidine-1-carboxylic acid benzyl ester
A solution of 8.526 mmol of (3R,4R,5S)-4-[4-((S)-3-methoxy-2-methyl-propoxy- methyl)-phenyl]-3-[4-(3-methoxy-propyl)-3-oxo-3,4-dihydro-2H-benzo[1 ,4]oxazin-6- ylmethoxy]-5-thtyloxymethyl-piperidine-1-carboxylic acid benzyl ester in 20 ml of tetrahydrofuran and 80 ml of methanol is treated with 12.789 mmol of toluene-4- sulfonic acichmonohydrate. After stirring for 15 hours, the reaction mixture is basified with saturated aqueous sodium bicarbonate solution and concentrated under reduced pressure to remove most of the methanol and tetrahydrofuran. The residue is extracted with dichloromethane (3X) - the combined organic layers are washed successively with water and brine, dried with sodium sulfate and evaporated. The title compound is obtained as a yellow oil from the residue by flash chromatography (SiO2 60F). Rt = 4.86 (gradient I).
c) (3R,4R,5S)-4-r4-((S)-3-Methoxy-2-methyl-propoxymethyl)-phenyll-3-r4-(3- methoxy-propyl)-3-oxo-3,4-dihvdro-2H-benzo[1 ,41oxazin-6-ylmethoxy1-5- trityloxymethyl-piperidine-i-carboxylic acid benzyl ester
According to general procedure D, (3R,4R,5S)-3-hydroxy-4-[4-((S)-3-methoxy-2- methyl-propoxymethyl)-phenyl]-5-thtyloxymethyl-piperidine-1 -carboxylic acid benzyl ester and 6-chloromethyl-4-(3-methoxy-propyl)-4H-benzo[1 ,4]oxazin-3-one [857272- 02-7] are used to afford the title compound as a yellow oil. Rt = 6.58 (gradient I).
d) (3R,4R,5S)-3-Hvdroxy-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)-phenyl1-5- trityloxymethyl-piperidine-i-carboxylic acid benzyl ester
8.478 mmol of benzyl chloroformate are added dropwise to a mixture of 8.478 mmol of (3R,4R,5S)-4-[4-((S)-3-methoxy-2-methyl-propoxymethyl)-phenyl]-5-thtyloxy- methyl-piperidin-3-ol (L)-(+)-mandelate in 150 ml of ethyl acetate and 150 ml of saturated aqueous sodium bicarbonate solution at 00C. After 1 hour, the reaction mixture is partitioned between saturated aqueous sodium carbonate solution and ethyl acetate - the organic layer is washed successively with water and brine. The combined aqueous layers are back-extracted with ethyl acetate - the combined organic layers are dried with sodium sulfate and evaporated. The crude title compound is obtained as a white foam. Rt = 6.14 (gradient I).
e) (3R,4R,5S)-4-r4-((S)-3-Methoxy-2-methyl-propoxymethyl)-phenyl1-5- trityloxymethyl-piperidin-3-ol (L)-(+)-mandelate
According to general procedure A, (3R,4R,5S)-1 -benzyl-4-[4-((S)-3-methoxy-2- methyl-propoxymethyl)-phenyl]-5-thtyloxymethyl-piperidin-3-ol (L)-(+)-mandelate is used to afford the title compound as a white foam. Rt = 4.92 (gradient I). f) (3R,4R,5S)-1 -Benzyl-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)-phenyl1-5- trityloxymethyl-piperidin-3-ol (L)-(+)-mandelate
2.36 mmol of (L)-(+)-mandelic acid are added to a solution of 5.90 mmol of (rac- 3R,4R,5S)-1-benzyl-4-[4-((S)-3-methoxy-2-nnethyl-propoxynnethyl)-phenyl]-5-tntyloxy- methyl-piperidin-3-ol in 36 ml of tetrahydrofuran at 600C (oil bath temperature). 36 ml of n-hexane are slowly added dropwise at 600C. The mixture is slowly cooled to room temperature over the course of 3 hours and, after a brief treatment in an ultrasonic bath, then cooled at 0°C for 2 hours. The precipitate is filtered off and washed with 1 :4 tetrahydrofuran/n-hexane to afford the title compound as a white solid. Rt = 5.36 (gradient I).
For analytical purposes, a small amount of the salt is dissolved in ethyl acetate and washed with saturated aqueous sodium carbonate solution (2X). The organic phase is washed with brine, dried with sodium sulfate and evaporated to afford the title compound as the free base (white solid). HPLC; Rt = 12.81 (Daicel Chiralpak AD 0.46 x 25 cm; 95% hexane/5% isopropanol; 0.7 ml/minute for 60 minutes).
g) (rac-3R,4R,5S)-1-Benzyl-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)-phenyl1- 5-trityloxymethyl-piperidin-3-ol
86.852 mmol of a solution of borane-tetrahydrofuran (1 M/THF) are added dropwise to a solution of 43.426 mmol of 1 -benzyl-4-[4-((S)-3-methoxy-2-methyl-propoxy- methyl)-phenyl]-3-(R,S)-thtyloxymethyl-1 ,2,3,6-tetrahydro-pyhdine in 220 ml of tetrahydrofuran at room temperature. After overnight stirring, the reaction mixture is cooled to 100C and successively treated dropwise with a solution of 251.871 mmol of potassium hydroxide in 60 ml of water and then with 86.852 mmol of hydrogen peroxide (30%/water). The reaction mixture is slowly warmed to 65°C, stirred for 3 hours and then re-cooled to room temperature. The reaction mixture is partitioned between tert-butyl methyl ether and ice-water - the organic layer is washed with brine. The combined aqueous layers are extracted with tert-butyl methyl ether (2X) - the combined organic layers are dried with sodium sulfate and evaporated. The residue is purified by flash chromatography (SiO2 60F) to afford the title compound as a yellow oil. Rf = 0.15 (EtOAc-heptane 1 :1 ); Rt = 5.36 (gradient I). h) 1 -Benzyl-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)-phenyl1-3-(R,S)- trityloxymethyl-1 ,2,3,6-tetrahvdro-pyridine
102.636 mmol of thionyl chloride are slowly added to a solution of 85.53 mmol of 1 -benzyl-4-[4-((S)-3-methoxy-2-methyl-propoxynnethyl)-phenyl]-3-(R,S)-tntyloxy- methyl-piperidin-4-(R,S)-ol in 250 ml of pyridine at 00C, taking care that the internal temperature stays below 100C. After 5 minutes, the reaction mixture is quenched by adding 50 ml of 4N NaOH solution and concentrated under reduced pressure. The residue is dissolved in ethyl acetate and washed successively with saturated aqueous sodium bicarbonate solution, water and brine, dried with sodium sulfate and evaporated. The residue is purified by flash chromatography (SiO2 60F) to afford the title compound as a yellow oil. Rf = 0.28 (EtOAc-heptane-25% ammonia cone. 100:200:1 ); Rt = 5.64 (gradient I).
i) 1 -Benzyl-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)-phenyl1-3-(R,S)-thtyloxy- methyl-piperidin-4-(R, S)-Ol
2.32 mmol of 1 ,2-dibromoethane are added to a suspension of 156.518 mmol of magnesium in 20 ml of tetrahydrofuran under argon at room temperature. The reaction mixture is warmed until the magnesium starts to react and then 3 ml of a solution of 151.509 mmol of 1 -bromo-4-((S)-3-methoxy-2-methyl-propoxymethyl)- benzene in 170 ml of tetrahydrofuran, followed by the rest of the solution, is added while maintaining a gentle reflux. After 2 hours, the reaction mixture is cooled to room temperature and then a solution of 125.214 mmol of 1 -benzyl-3-thtyloxymethyl- piperidin-4-one [234757-27-8] in 170 ml of tetrahydrofuran is slowly added, taking care to keep the internal reaction temperature under 40°C. After overnight stirring at room temperature, the reaction mixture is quenched with saturated aqueous ammonium chloride solution. Ethyl acetate is added to the reaction mixture and the phases separated - the organic phase is washed successively with water and brine. The combined aqueous phases are back-extracted with ethyl acetate - the combined organic phases are dried with sodium sulfate and evaporated. The residue is purified by flash chromatography (SiO2 60F) to afford the title compound as a yellow oil. Rf = 0.30 (EtOAc-heptane-25% ammonia cone. 100:100:1 ); Rt = 5.43 (gradient I). j) 1 -Bromo-4-((S)-3-methoxy-2-methyl-propoxymethyl)-benzene According to general method E, 1 -bromo-4-chloromethyl-benzene [589-17-3] and (R)-3-methoxy-2-methyl-propan-1-ol are used to afford the title compound as a yellow oil. Rf = 0.44 (EtOAc-heptane 1 :6); Rt = 5.29 (gradient I).
k) (R)-3-Methoxy-2-methyl-propan-1-ol
According to general method F, thisopropyl-(3-methoxy-2(S)-methylpropoxy)silane is used to afford the title compound as a yellow oil. Rf = 0.42 (dichloromethane- diethylether 1 :1 ).
I) Thisopropyl-((S)-3-methoxy-2-methylpropoxy)silane
3.09 g of sodium hydride (60% dispersion in oil) are added to a solution of 9.55 g of (S)-2-methyl-3-triisopropylsilanyloxypropan-1-ol [256643-28-4] and 7.3 ml of methyl iodide in 70 ml of N,N-dimethylformamide at 00C. After 60 hours at room temperature, the reaction mixture is diluted with tert-butyl methyl ether and washed successively with water and brine, dried with sodium sulfate and evaporated. The residue is purified by flash chromatography (SiO2 60F) to afford the title as a yellow oil. Rf = 0.51 (EtOAc-heptane 1 :10).
Example 2
N-{(3S,4R,5R)-4-r4-((S)-3-Methoxy-2-methyl-propoxymethyl)-phenyl1-5-[4-(3- methoxy-propyl)-3,4-dihvdro-2H-benzo[1 ,41oxazin-6-ylmethoxy1-piperidin-3-ylmethyl)- acetamide
According to general procedure A, (3R,4R,5R)-3-(acetylamino-methyl)-4-[4-((S)-3- methoxy-2-methyl-propoxymethyl)-phenyl]-5-[4-(3-methoxy-propyl)-3,4-dihydro-2H- benzo[1 ,4]oxazin-6-ylmethoxy]-piperidine-1 -carboxylic acid benzyl ester is used to afford the title compound.
The starting material(s) is(are) prepared as follows: a) (3R,4R,5R)-3-(Acetylamino-methyl)-4-[4-((S)-3-methoxy-2-methyl- propoxymethyl)-phenvH-5-[4-(3-methoxy-propyl)-3,4-dihvdro-2H- benzo[1 ,41oxazin-6-ylmethoxy1-piperidine-1 -carboxylic acid benzyl ester 5.936 mmol of acetyl chloride are added to a solution of 5.396 mmol of (3R,4R,5R)-3- aminomethyl-4-[4-((S)-3-methoxy-2-methyl-propoxymethyl)-phenyl]-5-[4-(3-methoxy- propyl)-3,4-dihydro-2H-benzo[1 ,4]oxazin-6-ylmethoxy]-piperidine-1 -carboxylic acid benzyl ester and 6.475 mmol of triethylamine in 80 ml of dichloromethane under argon at 00C. After 30 minutes, the reaction mixture is quenched with saturated aqueous sodium bicarbonate solution and extracted with tert-butyl methyl ether (2X). The combined organic layers are washed successively with water and brine, dried with sodium sulfate and evaporated. The residue is purified by flash chromatography (SiO2 60F) to afford the title compound as a yellow oil. Rt = 4.98 (gradient I).
b) (3R,4R,5R)-3-Aminomethyl-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)- phenyl1-5-r4-(3-methoxy-propyl)-3,4-dihvdro-2H-benzoπ ,41oxazin-6-ylmethoxy1- piperidine-1 -carboxylic acid benzyl ester
7.128 mmol of thphenylphosphine are added to a solution of 5.940 mmol of (3S,4R,5R)-3-azidomethyl-4-[4-((S)-3-methoxy-2-methyl-propoxymethyl)-phenyl]-5- [4-(3-methoxy-propyl)-3,4-dihydro-2H-benzo[1 ,4]oxazin-6-ylmethoxy]-piperidine-1 - carboxylic acid benzyl ester in 20 ml of methanol, 20 ml of tetrahydrofuran, 5 ml of water and 3.56 ml of concentrated aqueous ammonia (25%) at room temperature. After overnight stirring, the reaction mixture is partitioned between tert-butyl methyl ether and 5:1 water/saturated aqueous sodium bicarbonate solution. The aqueous layer is extracted with tert-butyl methyl ether - the combined organic layers are washed successively with water and brine, dried with sodium sulfate and evaporated. The residue is purified by flash chromatography (SiO2 60F) to afford the title compound as a yellow oil. Rf = 0.42 (dichloromethane-methanol-25% ammonia cone. 200:20:1 ); Rt = 4.64 (gradient I).
c) (3S,4R,5R)-3-Azidomethyl-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)-phenyl1- 5-[4-(3-methoxy-propyl)-3,4-dihvdro-2H-benzo[1 ,41oxazin-6-ylmethoxy1- piperidine-1 -carboxylic acid benzyl ester
31.265 mmol of sodium azide are added to a solution of 6.253 mmol of (3R,4R,5S)-4- [4-((S)-3-methoxy-2-methyl-propoxymethyl)-phenyl]-3-[4-(3-methoxy-propyl)-3,4- dihydro-2H-benzo[1 ,4]oxazin-6-ylmethoxy]-5-(toluene-4-sulfonyloxymethyl)- piperidine-1 -carboxylic acid benzyl ester in 50 ml of 1 ,3-dimethyl-tetrahydro- pyrimidin-2-one (DMPU) under argon at 45°C. After 5 hours, the reaction mixture is cooled to room temperature, diluted with tert-butyl methyl ether, washed with water and brine, dried with sodium sulfate and evaporated. The crude title compound is obtained as a yellow oil. Rf = 0.58 (EtOAc-heptane 2:1 ); Rt = 5.96 (gradient I).
d) (3R,4R,5S)-4-r4-((S)-3-Methoxy-2-methyl-propoxymethyl)-phenyll-3-r4-(3- methoxy-propyl)-3,4-dihvdro-2H-benzoπ ,41oxazin-6-ylmethoxy1-5-(toluene-4- sulfonyloxymethyl)-piperidine-1 -carboxylic acid benzyl ester 7.077 mmol of 4-methyl-benzenesulfonyl chloride are added to a solution of 6.583 mmol of (3S,4R,5R)-3-hydroxymethyl-4-[4-((S)-3-methoxy-2-methyl-propoxymethyl)- phenyl]-5-[4-(3-methoxy-propyl)-3,4-dihydro-2H-benzo[1 ,4]oxazin-6-ylmethoxy]- piperidine-1 -carboxylic acid benzyl ester (Example 1 a), 9.875 mmol of thethylamine and 0.329 mmol of dimethyl-pyhdin-4-yl-amine in 65 ml of dichloromethane under argon at 00C. After overnight stirring at room temperature, the reaction mixture is diluted with tert-butyl methyl ether, washed successively with saturated aqueous sodium bicarbonate solution, water and brine, dried with sodium sulfate and evaporated. The crude title compound is obtained as a yellow oil. Rf = 0.44 (EtOAc- heptane 2:1 ); Rt = 5.94 (gradient I).
According to the procedures described in example 2, the following compounds are prepared in an analogous manner:
3 N-{(3S,4R,5R)-4-r4-((S)-3-Methoxy-2-methyl-propoxymethyl)-phenyll-5-r4-(3- methoxy-propyl)-3,4-dihvdro-2H-benzori ,41oxazin-6-ylmethoxy1-piperidin-3- ylmethvD-propionamide using propionyl chloride instead of acetyl chloride in step a.
7 N-{(3S,4R,5R)-4-r4-((S)-3-Methoxy-2-methyl-propoxymethyl)-phenyll-5-r4-(3- methoxy-propyl)-3,4-dihvdro-2H-benzori ,41oxazin-6-ylmethoxy1-piperidin-3- ylmethylMormamide replacing step a with the following procedure: 1.4 mmol of 4-nitrophenylformiate are added to a solution of 1 mmol of (3R,4R,5R)-3- aminomethyl-4-[4-((S)-3-methoxy-2-methyl-propoxymethyl)-phenyl]-5-[4-(3-methoxy- propyl)-3,4-dihydro-2H-benzo[1 ,4]oxazin-6-ylmethoxy]-piperidine-1 -carboxylic acid benzyl ester (example 2b) in 10 ml of dichloromethane under argon followed by the addition of 1 mmol of thethylamine. After 60 minutes, the reaction mixture is evaporated. The residue is purified by flash chromatography (SiO2 60F) to afford the title compound, which is identified based on the Rf value.
Example 4
6-{(3R,4R,5S)-5-Methoxymethyl-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)- phenyl1-piperidin-3-yloxymethyl)-4-(3-methoxy-propyl)-3,4-dihvdro-2H- benzoH ,41oxazine
According to general procedure A, (3S,4R,5R)-3-methoxymethyl-4-[4-((S)-3-methoxy-
2-methyl-propoxymethyl)-phenyl]-5-[4-(3-methoxy-propyl)-3,4-dihydro-2H- benzo[1 ,4]oxazin-6-ylmethoxy]-piperidine-1 -carboxylic acid benzyl ester is used to afford the title compound.
The starting material(s) is(are) prepared as follows: a) (3S,4R,5R)-3-Methoxymethyl-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)- phenyl1-5-r4-(3-methoxy-propyl)-3,4-dihvdro-2H-benzoπ ,41oxazin-6-ylmethoxy1- piperidine-1 -carboxylic acid benzyl ester
2.568 mmol of methyl iodide are added to a suspension of 0.642 mmol of (3S,4R,5R)-3-hydroxymethyl-4-[4-((S)-3-methoxy-2-methyl-propoxymethyl)-phenyl]- 5-[4-(3-methoxy-propyl)-3,4-dihydro-2H-benzo[1 ,4]oxazin-6-ylmethoxy]-piperidine-1- carboxylic acid benzyl ester (Example 1 a) and 0.963 mmol of sodium hydride (60% dispersion in oil) under argon at 00C. After stirring for 1 hour at 00C and 1 hour at room temperature, the reaction mixture is partitioned between tert-butyl methyl ether and saturated aqueous sodium bicarbonate solution. The aqueous layer is extracted with tert-butyl methyl ether (2X) - the combined organic layers are washed successively with water and brine, dried with sodium sulfate and evaporated. The residue is purified by flash chromatography (SiO2 60F) to afford the title compound as a yellow oil. Rf = 0.41 (EtOAc-heptane 1 :1 ); Rt = 5.87 (gradient I). According to the procedures described in example 4, the following compound is prepared in an analogous manner:
6 6-{(3R,4R,5S)-5-(2-Methoxy-ethoxymethyl)-4-r4-((S)-3-methoxy-2-methyl- propoxymethyl)-phenyl1-piperidin-3-yloxymethyl)-4-(3-methoxy-propyl)-3,4- dihydro-2H-benzo[1 ,41oxazine using 1 -bromo-2-methoxy-ethane (instead of methyl iodide) and 1 equivalent of tetrabutylammonium iodide in step a.
Example 5
Acetic acid (3S,4R,5R)-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)-phenyl1-5-r4-(3- methoxy-propyl)-3,4-dihvdro-2H-benzori ,41oxazin-6-ylmethoxy1-piperidin-3-yl methyl ester
According to general procedure A, (3S,4R,5R)-3-acetoxymethyl-4-[4-((S)-3-methoxy-
2-methyl-propoxymethyl)-phenyl]-5-[4-(3-methoxy-propyl)-3,4-dihydro-2H- benzo[1 ,4]oxazin-6-ylmethoxy]-piperidine-1 -carboxylic acid benzyl ester is used to afford the title compound.
The starting material(s) is(are) prepared as follows: a) (3S,4R,5R)-3-Acetoxymethyl-4-r4-((S)-3-methoxy-2-methyl-propoxymethyl)- phenyl1-5-r4-(3-methoxy-propyl)-3,4-dihvdro-2H-benzoπ ,41oxazin-6-ylmethoxy1- piperidine-1 -carboxylic acid benzyl ester
Analogously to Example 2a, (3S,4R,5R)-3-hydroxymethyl-4-[4-((S)-3-methoxy-2- methyl-propoxymethyl)-phenyl]-5-[4-(3-methoxy-propyl)-3,4-dihydro-2H- benzo[1 ,4]oxazin-6-ylmethoxy]-piperidine-1 -carboxylic acid benzyl ester (Example 1 a) and acetyl chloride are used to afford the title compound as a colorless oil. Rf = 0.20 (EtOAc-heptane 1 :1 ); Rt = 5.69 (gradient I).

Claims

Claims
1. A compound of formula
(I) for the inhibition of beta-secretase, cathepsin D, plasmepsin Il and/or HIV-protease or its pharmaceutically acceptable salt, in which
R1 is straight-chain Ci-s-alkanoyloxy, straight-chain Ci-s-alkoxy, straight-chain Ci-S- alkoxy-straight-chain-Ci-s-alkoxy, straight-chain Ci-s-alkoxycarbonylamino, straight- chain Co-8-alkylcarbonylamino, optionally N-mono- or N,N-di-Ci-8-alkylated amino or hydroxy or straight-chain omega-hydroxy-Ci-s-alkyl.
2. Compound according to claim 1 wherein
R1 is hydroxy or straight-chain omega-hydroxy -Ci-s-alkyl.
3. Compound according to claim 1 wherein R1 is straight-chain Ci-s-alkanoyloxy.
4. Compound according to claim 1 wherein R1 is straight-chain Co-8-alkylcarbonylamino.
5. Compound according to claim 1 wherein
R1 is optionally N-mono- or N,N-di-straight-chain-Ci-8-alkylated amino.
6. Compound according to claim 1 wherein
R1 is hydroxy, methoxy, 2-methoxy-ethoxy, acetyloxy, formamido, methylcarbonylamino or ethylcarbonylamino.
7. A compound of the general formula (I), or a pharmaceutically acceptable salt thereof, according to any one of claims 1 to 6 for the prevention, delay of progression or treatment of Alzheimer Disease, malaria or HIV infection.
8. A pharmaceutical preparation for the prevention, delay of progression or treatment of Alzheimer disease, malaria or HIV infection, whereby said preparation contains a compound of the general formula (I), or a pharmaceutically acceptable salt thereof, according to any one of claims 1 to 6, as well as commonly used ingredients.
EP09728288A 2008-04-02 2009-04-01 Substituted piperidines as therapeutic compounds Withdrawn EP2271644A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP09728288A EP2271644A1 (en) 2008-04-02 2009-04-01 Substituted piperidines as therapeutic compounds

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
EP08153929 2008-04-02
EP09728288A EP2271644A1 (en) 2008-04-02 2009-04-01 Substituted piperidines as therapeutic compounds
PCT/EP2009/053898 WO2009121914A1 (en) 2008-04-02 2009-04-01 Substituted piperidines as therapeutic compounds

Publications (1)

Publication Number Publication Date
EP2271644A1 true EP2271644A1 (en) 2011-01-12

Family

ID=40627638

Family Applications (1)

Application Number Title Priority Date Filing Date
EP09728288A Withdrawn EP2271644A1 (en) 2008-04-02 2009-04-01 Substituted piperidines as therapeutic compounds

Country Status (10)

Country Link
EP (1) EP2271644A1 (en)
JP (1) JP2011516453A (en)
KR (1) KR20110002459A (en)
CN (1) CN101970431A (en)
AU (1) AU2009232012A1 (en)
BR (1) BRPI0910991A2 (en)
CA (1) CA2719070A1 (en)
EA (1) EA201001517A1 (en)
MX (1) MX2010010876A (en)
WO (1) WO2009121914A1 (en)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011057160A2 (en) * 2009-11-06 2011-05-12 The Regents Of The Uiversity Of California Method to improve the immunogenicity of vaccine antigens by modification of cleavage sites in hiv-1 gp 120
JP5099731B1 (en) 2009-10-14 2012-12-19 メルク・シャープ・アンド・ドーム・コーポレーション Substituted piperidines that increase p53 activity and uses thereof
GB201008209D0 (en) * 2010-05-17 2010-06-30 Senexis Ltd Compounds
WO2013062923A1 (en) 2011-10-28 2013-05-02 Merck Sharp & Dohme Corp. MACROCYCLES THAT INCREASE p53 ACTIVITY AND THE USES THEREOF
EP2935263B1 (en) 2012-12-20 2018-12-05 Merck Sharp & Dohme Corp. Substituted imidazopyridines as hdm2 inhibitors
CN105001300A (en) * 2014-04-17 2015-10-28 复旦大学 Cathepsin D inhibitor, preparation method, pharmaceutical composition and applications thereof

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1816122A3 (en) * 2006-01-19 2007-09-19 Speedel Experimenta AG 3,4,5-substituted piperidines as therapeutic compounds
EP1911758A1 (en) * 2006-10-04 2008-04-16 Speedel Experimenta AG Phenyl piperidine derivatives for use as renin inhibitors
EP1908761A1 (en) * 2006-10-04 2008-04-09 Speedel Experimenta AG Organic compounds

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2009121914A1 *

Also Published As

Publication number Publication date
EA201001517A1 (en) 2011-04-29
KR20110002459A (en) 2011-01-07
MX2010010876A (en) 2010-10-26
JP2011516453A (en) 2011-05-26
BRPI0910991A2 (en) 2016-01-19
CN101970431A (en) 2011-02-09
AU2009232012A1 (en) 2009-10-08
CA2719070A1 (en) 2009-10-08
WO2009121914A1 (en) 2009-10-08

Similar Documents

Publication Publication Date Title
JP7319395B2 (en) Inhibitor of SARM1
ES3028093T3 (en) Inhibitors of sarm1
US20070167433A1 (en) 3,4,5-Substituted piperidines as therapeutic compounds
AU2021333558A1 (en) Inhibitors of SARM1
US20070066582A1 (en) Diaminoalcohols as therapeutic compounds
WO2009121914A1 (en) Substituted piperidines as therapeutic compounds
CA3123215A1 (en) Inhibitors of sarm1 in combination with neuroprotective agents
JP7477642B2 (en) SARM1 inhibitors
JP7746384B2 (en) Benzopyrazole inhibitors of SARM1
EP4028013A1 (en) Inhibitors of sarm1
EP1958666A1 (en) Heterocyclic-substituted alkanamides as therapeutic compounds
WO2009106599A2 (en) Substituted piperidines as therapeutic compounds
US20070021413A1 (en) Diamino alcohols as therapeutic compounds
EP1867329A2 (en) 5-Amino-4-hydroxy-2-isopropyl-7-[4-methoxy-3-(3-methoxypropoxy)benzyl]-8-methylnonanamides as therapeutic compounds
EP1987834A2 (en) Substituted piperidines as therapeutic compounds
US20070021400A1 (en) Amino alcohols as therapeutic compounds
US20070066604A1 (en) Diaminoalcohols as therapeutic compounds
EP1872780A2 (en) Omega-Phenyloctanamides as therapeutic compounds
US20070021399A1 (en) Amido-amino alcohols as therapeutic compounds
EP1958634A2 (en) Substituted piperidines as inhibitors of beta-secretase, cathepsin D, plasmepsin II and/or HIV protease
EP2018862A1 (en) Substituted piperidines as therapeutic compounds
CN114989049A (en) Vif inhibitor and application thereof in preparation of anti-HIV (human immunodeficiency virus) medicines

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20101102

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK TR

AX Request for extension of the european patent

Extension state: AL BA RS

DAX Request for extension of the european patent (deleted)
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20101228