WO2014184356A1 - Perhydroquinoxaline derivatives useful as analgesics - Google Patents

Perhydroquinoxaline derivatives useful as analgesics Download PDF

Info

Publication number
WO2014184356A1
WO2014184356A1 PCT/EP2014/060114 EP2014060114W WO2014184356A1 WO 2014184356 A1 WO2014184356 A1 WO 2014184356A1 EP 2014060114 W EP2014060114 W EP 2014060114W WO 2014184356 A1 WO2014184356 A1 WO 2014184356A1
Authority
WO
WIPO (PCT)
Prior art keywords
alkyl
group
coo
chosen
radical
Prior art date
Application number
PCT/EP2014/060114
Other languages
French (fr)
Inventor
Michael Soeberdt
Ulrich Knie
Christoph Abels
Original Assignee
Dr. August Wolff Gmbh & Co. Kg Arzneimittel
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 Dr. August Wolff Gmbh & Co. Kg Arzneimittel filed Critical Dr. August Wolff Gmbh & Co. Kg Arzneimittel
Publication of WO2014184356A1 publication Critical patent/WO2014184356A1/en

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07DHETEROCYCLIC COMPOUNDS
    • C07D241/00Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings
    • C07D241/36Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings condensed with carbocyclic rings or ring systems
    • C07D241/38Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings condensed with carbocyclic rings or ring systems with only hydrogen or carbon atoms directly attached to the ring nitrogen atoms
    • C07D241/40Benzopyrazines
    • C07D241/42Benzopyrazines with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to carbon atoms of the hetero ring
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61PSPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P29/00Non-central analgesic, antipyretic or antiinflammatory agents, e.g. antirheumatic agents; Non-steroidal antiinflammatory drugs [NSAID]
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07DHETEROCYCLIC COMPOUNDS
    • C07D401/00Heterocyclic compounds containing two or more hetero rings, having nitrogen atoms as the only ring hetero atoms, at least one ring being a six-membered ring with only one nitrogen atom
    • C07D401/02Heterocyclic compounds containing two or more hetero rings, having nitrogen atoms as the only ring hetero atoms, at least one ring being a six-membered ring with only one nitrogen atom containing two hetero rings
    • C07D401/04Heterocyclic compounds containing two or more hetero rings, having nitrogen atoms as the only ring hetero atoms, at least one ring being a six-membered ring with only one nitrogen atom containing two hetero rings directly linked by a ring-member-to-ring-member bond
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07DHETEROCYCLIC COMPOUNDS
    • C07D405/00Heterocyclic compounds containing both one or more hetero rings having oxygen atoms as the only ring hetero atoms, and one or more rings having nitrogen as the only ring hetero atom
    • C07D405/02Heterocyclic compounds containing both one or more hetero rings having oxygen atoms as the only ring hetero atoms, and one or more rings having nitrogen as the only ring hetero atom containing two hetero rings
    • C07D405/06Heterocyclic compounds containing both one or more hetero rings having oxygen atoms as the only ring hetero atoms, and one or more rings having nitrogen as the only ring hetero atom containing two hetero rings linked by a carbon chain containing only aliphatic carbon atoms
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07BGENERAL METHODS OF ORGANIC CHEMISTRY; APPARATUS THEREFOR
    • C07B2200/00Indexing scheme relating to specific properties of organic compounds
    • C07B2200/07Optical isomers

Definitions

  • the present invention relates to perhydroquinoxaline derivatives and medicaments containing perhydroquinoxaline derivatives.
  • Analgesic agents as a rule act by activating opioid receptors.
  • Conventional opioids such as morphine, are thus opioid analgesics which are often employed in clinical pain therapy because of their potent analgesic action. These activate the ⁇ receptor.
  • undesirable side effects of such pain therapy are sometimes considerable centrally mediated side effects, such as respiratory depression, vomiting and bradycardia. Possible psycho-dependencies are furthermore a disadvantage.
  • opioids in treating different types of pain and diseases associated with pain, there is a great need for new active compounds suitable to treat side effects of opioid adminstration (commonly also called “(analgesic) opioid induced side effects”).
  • WO2009/080745 relates to perhydroquinoxaline derivatives useful as analgesic agents.
  • the invention was based on the object to provide novel compounds which can be used as pharmaceutical active compounds, in particular for treating and/or preventing analgesic opioid induced side effects.
  • R 1 is chosen from the group comprising H; Ci-Cio-alkyl; C 3 -Cio-cycloalkyl; (COO(Ci-Cio-alkyl);
  • phenylalkyl with Ci-C 6 -alkyl wherein the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising halogen, Ci-C 6 - alkyloxy, NH 2 , NH(C C 5 -alkyl), N(C C 5 -alkyl) 2 , OH, S0 2 (CrC 5 -alkyl), SO(C C 5 -alkyl), CF 3 , CN, N0 2 , S0 2 N(Ci-C 5 -alkyl) 2 , S0 2 NH 2 , S0 2 NH(Ci-C 5 -alkyl), S0 2 NH(aryl), S0 2 NH(phenyl) and/or S0 2 NH(heteroaryl);
  • Ci-Cio-acyl containing one, two, three or four hetero atoms chosen from the group comprising NH, O and/or S; phenylacyl, wherein the acyl radical is a Ci-C 6 -acyl radical and the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising halogen, Ci-C 6 -alkyloxy, COO(Ci-C 6 - alkyl), NH 2 , NH(Ci-C 5 -alkyl), N(Ci-C 5 -alkyl) 2 , CONH 2 , CONH(Ci-C 6 -alkyl), CON(Ci-C 6 - alkyl) 2 , OH, S0 2 (Ci-C 5 -alkyl), SO(Ci-C 5 -alkyl), CF 3 , CN, N0 2 , S0 2 N(Ci-C 5 -alkyl) 2
  • heteroarylalkyl containing one, two, three or four hetero atoms chosen from the group comprising N, O and/or S, wherein the alkyl radical is a Ci-C 6 alkyl radical;
  • acyl radical is a Ci-C 6 - acyl radical and the heteroaryl radical can be substituted by one or more identical or different groups chosen from the group comprising halogen, Ci-C 6 -alkyloxy, COO(Ci-C 6 -alkyl), NH 2 , NH(C C 5 -alkyl), N(CrC 5 -alkyl) 2 , CONH 2 , CONH(C C 6 -alkyl), CON(C C 6 -alkyl) 2 , OH, CF 3 , CN, N0 2 , and/or S0 2 NH 2 ;
  • acyl radical is a Ci-C 6 -acyl radical and the alkenyl radical is a C 2 -C 6 -alkenyl radical;
  • C 6 -alkyl wherein k is 0, 1, 2, 3 or 4; C(0)NH-(CH 2 )i-CONH 2 , wherein 1 is 0, 1, 2, 3 or 4;
  • COO-(CH 2 ) m -COOH wherein m is 0, 1, 2, 3 or 4; COO-(CH 2 ) n -COO(C C 10 - alkyl), wherein n is 0, 1, 2, 3 or 4; COO-(CH 2 ) p -C(0)NH 2 , wherein p is 0, 1, 2, 3 or 4; C(O)- (CH 2 ) q -COOH, wherein q is 0, 1, 2, 3 or 4; C(O)-(CH 2 ) r -COO(Ci-Ci 0 -alkyl), wherein r is 0, 1, 2, 3 or 4; C(0)-(CH 2 ) s -C(0)NH 2 , wherein s is 0, 1, 2, 3 or 4; C(0)-(CH 2 ) t -C(0)NH(C 1 -C 6 - alkyl), wherein t is 0, 1, 2, 3 or 4; C(0)-(CH 2 ) u -C(0)N(C C 6 -
  • R 2 , R 3 are in each case identical or independent of each other and are chosen from the group comprising H; Ci-Cio-alkyl; C 3 -Cio-cycloalkyl,
  • R 2 and R 3 form, together with the nitrogen to which they are bonded, a saturated or unsaturated 3- to 8-membered N-heterocycle, wherein this can be substituted by one or more identical or different groups chosen from the group comprising halogen, OH, Cp C 4 -alkyloxy, COOH, COO(C C 10 -alkyl), CONH 2 , CONH(C C 10 -alkyl), CON(C C 10 - alkyl) 2 , CN, and/or 0-C(0)(Ci-C 6 alkyl);
  • A is chosen from the group comprising (CH 2 ) b , wherein b is 0, 1, 2, 3, 4, 5, or 6;
  • C 2 -C5 alkylene which can be substituted by at least one C 1 -C3 alkyl radical; O; S; NH and/or aryl; Z is chosen from the group comprising H; NH 2 ; COOH; COO(Ci-Cs-alkyl);
  • phenyl which can be substituted by one or more identical or different groups chosen from the group comprising halogen, C C 5 -alkyl, C C 5 -alkoxy, NH 2 , NH(C C 5 -alkyl), N(C C 5 - alkyl) 2 , OH, S0 2 (Ci-C 5 -alkyl), SO(Ci-C 5 -alkyl), CF 3 , CN, N0 2 , S0 2 N(Ci-C 5 -alkyl) 2 , SO 2 NH 2 , S0 2 NH(Ci-C 5 -alkyl), S0 2 NH(aryl), S0 2 NH(phenyl) and/or S0 2 NH(heteroaryl), wherein the substituents may form a ring;
  • aryl or heteroaryl containing one or two hetero atoms chosen from the group comprising N, O and/or S, wherein the aryl or heteroaryl group can be substituted by one or more identical or different groups chosen from the group comprising halogen, Ci-C 4 -alkoxy, NH 2 , NH(Ci-C 5 -alkyl), N(Ci-C 5 -alkyl) 2 , OH, S0 2 (Ci-C 5 -alkyl), SO(Ci-C 5 -alkyl), CF 3 , CN, N0 2 , S0 2 N(Ci-C 5 -alkyl) 2 , S0 2 NH 2 , S0 2 NH(Ci-C 5 -alkyl), S0 2 NH(aryl), S0 2 NH(phenyl) and/or S0 2 NH(heteroaryl).
  • the perhydroquinoxaline compounds of formula (1) according to the invention are named following the IUPAC nomenclature.
  • the stereochemistry of the compounds of formula (1) follow the CIP nomenclature (Cahn-Ingold-Prelog) and may be specified as (4aS,5R,8aR) as long as the radical R 1 has the highest priority.
  • the stereochemistry is defined as (4aR,8R,8aS).
  • heteroaryl is to be understood as meaning mono-, bi- or tricyclic heteroaryl containing one, two, three or four hetero atoms chosen from the group comprising N, O and/or S.
  • Preferred heteroaryl radicals are chosen from the group comprising pyridinyl, pyrimidinyl, pyrazinyl, triazolyl, pyridazinyl, 1,3,5-triazinyl, quinolyl, isoquinolyl, quinolinyl, isoquinolinyl, quinoxalinyl, imidazolyl, pyrazolyl, benzimidazolyl, benzooxazolyl, benzothiazolyl, thiazolyl, oxazolyl, isoxazolyl, oxazolidinyl, pyrrolyl, carbazolyl, indolyl, isoindolyl, furyl, benzofuryl, benzofuranyl, 1,3-benzodioxolyl, thienyl and/or benzothienyl.
  • Ci-Cio-alkyl includes, unless stated otherwise, straight- chain, branched or cyclic alkyl groups, preferably chosen from the group comprising methyl, ethyl, n-/i-propyl, n-/i-/tert-butyl, pentyl, neopentyl, hexyl, heptyl, octyl, nonyl and/or decyl.
  • heterocyclyl includes saturated, mono- or diunsaturated cyclic alkyl radicals having 3 to 10 carbon atoms that contain one, two, three or four hetero atoms chosen from the group comprising NH, O and/or S.
  • Ci-C6-alkoxy groups according to the invention are preferably chosen from the group comprising methoxy, ethoxy, linear or branched propoxy and/or butoxy.
  • halogen according to the invention includes fluorine, chlorine, bromine and iodine, fluorine or chlorine being preferred, in particular chlorine.
  • aryl according to the invention includes aromatic radicals having 6 to 20 carbon atoms, preferably phenyl, naphthyl, indenyl, and biphenyl.
  • aryl also includes carbocycles.
  • acyl means "Cr Cio-acyl", namely including the groups HC(O)- (formyl) and (Ci-Cc))-C(0)-, wherein (C1-C9) means linear, branched or cyclic alkyl or alkenyl groups. HC(O)- (formyl) and CH 3 -C(0)- (acetyl) are preferred.
  • R 1 is chosen from the group comprising H; Ci-C 3 -alkyl; COO(Ci-C 4 -alkyl);
  • Ci-C 4 -acyl Ci-C 4 -acyl; C(0)(C 4 -C6-cycloalkyl); heterocyclylacyl containing NH or O in the ring; phenylacyl, wherein the acyl radical is a Ci-acyl radical and the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(C C 3 -alkyl) and CONH 2 ;
  • acyl radical is a Ci-acyl radical and the heteroaryl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(Ci-C 3 -alkyl) and CONH 2 ;
  • acyl radical is a Ci-acyl radical and the alkenyl radical is a C 2 -C 4 - alkenyl radical; C(0)NH(Ci-C 3 -alkyl); C(0)N(Ci-C 3 -alkyl) 2 , wherein the two alkyl radicals may form a saturated halogen substituted or unsubstituted ring with the N atom; C(0)NH(phenyl); C(0)NH(benzyl); C(0)(C 3 -C 6 -cycloalkyl); COO(benzyl);
  • COO-(CH 2 ) m -COOH wherein m is 0 or 1; COO-(CH 2 ) n -COO(C C 3 -alkyl), wherein n is 0 or 1; COO-(CH 2 ) p -C(0)NH 2 , wherein p is 0 or 1; C(0)-(CH 2 ) q -COOH, wherein q is 0 or 1; C(0)-(CH 2 ) r -COO(Ci-C 3 -alkyl), wherein r is 0 or 1; C(0)-(CH 2 ) s - C(0)NH 2 , wherein s is 0 or 1; C(0)-(CH 2 ) t -C(0)NH(C C 3 -alkyl), wherein t is 0 or 1; C(O)- (CH 2 ) u -C(0)N(C C 3 -alkyl) 2 , wherein u is 0 or 1;
  • R 2 , R 3 are identical or different and are chosen from the group comprising H, methyl, ethyl, n-propyl, and i-propyl,
  • R 2 and R 3 form, together with the nitrogen to which they are bonded, a saturated or mono-unsaturated 4- to 6-membered N-heterocycle, wherein this can be substituted by one or more identical or different groups chosen from the group comprising F, CI, OH, CONH 2 , CN, and/or 0-C(0)(C C 3 alkyl);
  • A is (CH 2 )b, wherein b is 1;
  • Z is chosen from the group comprising phenyl, which can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C3-alkyl, Ci-C3-alkoxy, OH, CF 3 , and N0 2 , wherein two OH substituents may be connected by an ether bridge to form a ring or wherein two Ci-C 3 -alkyl groups may be connected to form a saturated ring; and
  • aryl or heteroaryl containing one hetero atom chosen from the group of N and S, wherein the aryl or heteroaryl group can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C 3 -alkyl, Ci-C 3 - alkoxy, OH, CF 3 , and N0 2 . More preferably in the compound according to general formula (1):
  • R 1 is chosen from the group consisting of
  • Ci-acyl (formyl); heterocyclylacyl containing NH or O in the ring; phenylacyl, wherein the acyl radical is a Ci-acyl radical and the phenyl radical is substituted by one or more of COO(C C 3 -alkyl) and CONH 2 ;
  • acyl radical is a Ci-acyl radical and the heteroaryl radical is substituted by one or more of COO(Ci-C 3 -alkyl) and CONH 2 ;
  • acyl radical is a Ci-acyl radical and the alkenyl radical is a C 2 -C 4 - alkenyl radical;
  • COO-(CH 2 ) m -COOH wherein m is 0 or 1; COO-(CH 2 ) n -COO(C C 3 -alkyl), wherein n is 0 or 1; COO-(CH 2 ) p -C(0)NH 2 , wherein p is 0 or 1; C(0)-(CH 2 ) s -C(0)NH 2 , wherein s is 0 or 1; C(0)-(CH 2 ) t -C(0)NH(Ci-C 3 -alkyl), wherein t is 0 or 1; C(0)-(CH 2 ) u - C(0)N(Ci-C 3 -alkyl) 2 , wherein u is 0 or 1;
  • R 2 , R 3 are identical or different and are chosen from the group comprising H, methyl, ethyl, n-propyl, and i-propyl,
  • R 2 and R 3 form, together with the nitrogen to which they are bonded, a saturated or mono-unsaturated 4- to 6-membered N-heterocycle, wherein this can be substituted by one or more identical or different groups chosen from the group comprising F, CI, OH, CONH 2 , CN, and/or 0-C(0)(C C 3 alkyl);
  • A is (CH 2 )b, wherein b is 1;
  • Z is chosen from the group comprising
  • phenyl which can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C 3 -alkyl, Ci-C 3 -alkoxy, OH, CF 3 , and N0 2 , wherein two OH substituents may be connected by an ether bridge to form a ring or wherein two C 1 -C 3 - alkyl groups may be connected to form a saturated ring; and
  • aryl or heteroaryl group can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C 3 -alkyl, C 1 -C 3 - alkoxy, OH, CF 3 , and N0 2 .
  • R 1 is chosen from the group comprising H; Ci-C 3 -alkyl; COO(Ci-C4-alkyl);
  • Ci-C 4 -acyl Ci-C 4 -acyl; C(0)(C 4 -C6-cycloalkyl); heterocyclylacyl containing NH or O in the ring; phenylacyl, wherein the acyl radical is a Ci-acyl radical and the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(Ci-C 3 -alkyl) and CONH 2 ;
  • acyl radical is a Ci-acyl radical and the heteroaryl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(Ci-C 3 -alkyl) and CONH 2 ;
  • acyl radical is a Ci-acyl radical and the alkenyl radical is a C 2 -C 4 - alkenyl radical;
  • COO-(CH 2 ) m -COOH wherein m is 0 or 1; COO-(CH 2 ) n -COO(C C 3 -alkyl), wherein n is 0 or 1; COO-(CH 2 ) p -C(0)NH 2 , wherein p is 0 or 1; C(0)-(CH 2 ) q -COOH, wherein q is 0 or 1; C(0)-(CH 2 ) r -COO(Ci-C 3 -alkyl), wherein r is 0 or 1; C(0)-(CH 2 ) s - C(0)NH 2 , wherein s is 0 or 1; C(0)-(CH 2 ) t -C(0)NH(Ci-C 3 -alkyl), wherein t is 0 or 1; C(O)- (CH 2 ) u -C(0)N(Ci-C 3 -alkyl) 2 , wherein u is 0 or 1;
  • R and R form, together with the nitrogen to which they are bonded, a mono- unsaturated 6-membered N-heterocycle, that may be substituted by one or more of F, CI, OH, CONH 2 , CN, and/or 0-C(0)(Ci-C 3 alkyl);
  • A is (CH 2 ) b , wherein b is 1; Z is chosen from the group comprising
  • phenyl which can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C 3 -alkyl, Ci-C 3 -alkoxy, OH, CF 3 , and N0 2 , wherein two OH substituents may be connected by an ether bridge to form a ring or wherein two Ci-C 3 - alkyl groups may be connected to form a saturated ring; and
  • R 1 is chosen from the group comprising H; Ci-C 3 -alkyl; COO(Ci-C4-alkyl);
  • Ci-C 4 -acyl Ci-C 4 -acyl; C(0)(C 4 -C6-cycloalkyl); heterocyclylacyl containing NH or O in the ring; phenylacyl, wherein the acyl radical is a Ci-acyl radical and the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(C C 3 -alkyl) and CONH 2 ;
  • acyl radical is a Ci-acyl radical and the heteroaryl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(Ci-C 3 -alkyl) and CONH 2 ;
  • acyl radical is a Ci-acyl radical and the alkenyl radical is a C 2 -C 4 - alkenyl radical;
  • COO-(CH 2 ) m -COOH wherein m is 0 or 1; COO-(CH 2 ) n -COO(C C 3 -alkyl), wherein n is 0 or 1; COO-(CH 2 ) p -C(0)NH 2 , wherein p is 0 or 1; C(0)-(CH 2 ) q -COOH, wherein q is 0 or 1; C(0)-(CH 2 ) r -COO(Ci-C 3 -alkyl), wherein r is 0 or 1; C(0)-(CH 2 ) s - C(0)NH 2 , wherein s is 0 or 1; C(0)-(CH 2 ) t -C(0)NH(Ci-C 3 -alkyl), wherein t is 0 or 1; C(O)- (CH 2 ) u -C(0)N(C C 3 -alkyl) 2 , wherein u is 0 or 1;
  • R 2 , R 3 are identical or different and are chosen from the group comprising H, methyl, ethyl, n-propyl, and i-propyl,
  • R 2 and R 3 form, together with the nitrogen to which they are bonded, a saturated or mono-unsaturated 4- to 6-membered N-heterocycle, wherein this can be substituted by one or more identical or different groups chosen from the group comprising F, CI, OH, CONH 2 , CN, and/or 0-C(0)(Ci-C 3 alkyl);
  • A is (CH 2 )b, wherein b is 1;
  • Z is either a tetrahydronaphthyl or a 2,3-dihydrobenzo-l,4-dioxinyl residue, optionally substituted by one or more of F, CI, Ci-C 3 -alkyl, Ci-C 3 -alkoxy, OH, CF 3 , and N0 2 .
  • radicals R 1 according to the invention are as follows:
  • radicals Z are as follows: Without being bound by a particular theory, it is assumed that the action of the compounds according to the invention is not only based on the steric action of the perhydroquinoxaline group, in particular in combination with the structural element R 1 , but even more on the specific cis-trans stereochemistry and the (4aS,5R,8aR) form of the compounds as indicated in formula (1). Reference is made to the Biological Assay section of the application.
  • the compounds according to the invention can furthermore be used in the form of their acids or their bases or in the form of their salts, in particular the physiologically acceptable salts, or in the form of their solvates, in particular their hydrates.
  • the pharmaceutically acceptable salts can be base addition salts. These include salts of the compounds according to the invention with inorganic bases, such as alkali metal hydroxides, alkaline earth metal hydroxides, or with organic bases, such as mono-, di- or triethanolamine. Acid addition salts, in particular with inorganic acids, such as hydrochloric acid, sulfuric acid or phosphoric acid, or with suitable organic carboxylic or sulfonic acids, or with amino acids, can further advantageously be used.
  • inorganic bases such as alkali metal hydroxides, alkaline earth metal hydroxides, or with organic bases, such as mono-, di- or triethanolamine.
  • Acid addition salts in particular with inorganic acids, such as hydrochloric acid, sulfuric acid or phosphoric acid, or with suitable organic carboxylic or sulfonic acids, or with amino acids, can further advantageously be used.
  • salts of the compounds according to the invention are chosen, for example, from the group comprising chlorides, bromides, iodides, hydrochlorides, hydrobromides, sulfonates, methanesulfonates, sulfates, hydrogen sulfates, sulfites, hydrogen sulfites, phosphates, nitrates, methanoates, acetates, proprionates, lactates, citrates, glutarates, maleates, malonates, malates, succinates, tartrates, oxalates, fumarates, benzoates, p- toluenesulfonates and/or salts of amino acids, preferably the proteinogenic amino acids.
  • the compounds according to the invention are suitable for use as medicaments.
  • the compounds according to the invention can be used in particular for therapeutic and/or prophylactic treatment of side effects associated with opioid administration (opioid induced side effects) and diseases having the same or similar symptoms.
  • the side effects and/or diseases to be treated according to the invention preferably are selected from gastrointestinal dysfunction, inhibition of intestinal motility, constipation, GI sphincter constriction, nausea, emesis, biliary spasm, opioid bowel dysfunction, colic, dysphoria, pruritus, urinary retention, depression of respiration, papillary constriction, cardiovascular effects, chest wall rigidity and cough suppression, depression of stress response, and immune suppression associated with use of narcotic analgesia, or combinations thereof.
  • the side effects and/or diseases to be treated according to the invention may also be selected from irritable bowel syndrome, opioid-induced bowel dysfunction, colitis, post-operative or postpartum ileus, nausea and/or vomiting, decreased gastric motility and emptying, inhibition of the stomach, and small and/or large intestinal propulsion, increased amplitude of nonpropulsive segmental contractions, constriction of sphincter of Oddi, increased anal sphincter tone, impaired reflex relaxation with rectal distention, diminished gastric, biliary, pancreatic or intestinal secretions, increased absorption of water from bowel contents, gastro-esophageal reflux, gastroparesis, cramping, bloating, abdominal or epigastric pain and discomfort, constipation, idiopathic constipation, post-operative gastrointestinal dysfunction following abdominal surgery, and delayed absorption of orally administered medications or nutritive substances.
  • the compounds according to the invention may further be used as a medicament in the treatment of pain, in the treatment of inflammatory conditions such as inflammatory bowel syndrome, in the treatment of infectious diseases, in the treatment of diseases of the musculoskeletal system such as osteoporosis, arthritis, osteitis, periostitis, myopathies, treatment of autoimmune diseases and immune suppression, therapy of post-operative gastrointestinal dysfunction following abdominal surgery, idiopathic constipation, and ileus, and in the treatment of disorders such as cancers involving angiogenesis, chronic inflammation and/or chronic pain, sickle cell anemia, vascular wounds, and retinopathy.
  • inflammatory conditions such as inflammatory bowel syndrome
  • infectious diseases in the treatment of diseases of the musculoskeletal system such as osteoporosis, arthritis, osteitis, periostitis, myopathies, treatment of autoimmune diseases and immune suppression, therapy of post-operative gastrointestinal dysfunction following abdominal surgery, idiopathic constipation, and ileus
  • disorders such as cancers involving an
  • the patients suffering from the diseases to be treated according to the invention are preferably those receiving acute opioid therapy, such as a patient suffering from post-operative gastrointestinal dysfunction receiving acute opioid administration, or a subject receiving opioids chronically such as an AIDS patient, a cancer patient, a cardiovascular patient; a subject receiving chronic opioid therapy for pain management; or a subject receiving opioid therapy for maintenance of opioid withdrawal.
  • the compounds according to the invention can furthermore be used for treatment and/or prevention of pruritus, psoriasis, psoriatic arthritis, contact dermatitis, atopic eczema, scleroderma, systemic lupus erythematous, urticaria, lichen planus, lymphoma and/or allergies.
  • the compounds according to the invention or compositions containing these can be administered systemically or topically.
  • the compounds or compositions according to the invention are administered topically, in particular in the form of creams, ointments, plasters or tinctures.
  • prophylactic treatment is understood as meaning in particular that the compounds according to the invention can be administered before symptoms of a disease occur or the risk of a disease exists.
  • the medicaments according to the invention may further comprise at least one opioid receptor agonist.
  • morphine-6-glucoronide nalbuphine, nalorphine, nicomorphine, opium, oxycodone, oxymorphone, papavereturn, pentazocine, pethidin.
  • the medicaments according to the invention may further comprise at least one steroidal antiinflammatory drug, preferably chosen from the group of hydrocortisone, hydrocortisone acetate, prednisolone, methylprednisolone, prednisone, betamethasone, hydrocortisone- 17- valerate, betamethasone valerate, betamethasone dipropionate, prednicarbate, clobetasone-17- butyrate flunisolide, fluticasone propionate, triamcinolone acetonide, beclomethasone dipropionate, budesonide and/or hydrocortisone- 17-butyrate and/or a nonsteroidal anti- inflammatory drug (NSAID), preferably chosen from the group of aspirin, ibuprofen, diclofenac and/or naproxen, and/or an antibiotic.
  • NSAID nonsteroidal anti- inflammatory drug
  • the compounds according to the invention can be administered according to conventional methods, for example orally, dermally, intranasally, transmucosally, pulmonally, enterally, buccally, rectally, intraurethral, aural, by inhalation, by means of injection, for example intravenously, parenterally, intraperitoneally, intradermally, subcutaneously, topically and/or intramuscularly and/or locally, for example on painful areas of the body. Oral administration is particularly preferred.
  • the compounds according to the invention can be used in particular for the preparation of medicaments by being brought into a suitable dosage form together with at least one carrier substance or auxiliary substance, for example in the form of injection solutions, drops, juices, syrups, sprays, suspensions, tablets, patches, capsules, plasters, suppositories, ointments, creams, lotions, gels, emulsions, aerosols or in multiparticulate form, for example in the form of pellets or granules.
  • carrier substance or auxiliary substance for example in the form of injection solutions, drops, juices, syrups, sprays, suspensions, tablets, patches, capsules, plasters, suppositories, ointments, creams, lotions, gels, emulsions, aerosols or in multiparticulate form, for example in the form of pellets or granules.
  • compositions with delayed release are furthermore preferred for oral administration of the compounds according to the invention.
  • formulations with delayed release are sustained release matrix tablets, multilayered tablets, the coating of which can be, for example, constructed to be resistant to gastric juice, such as coatings based on shellac, sustained release capsules or formulations using biodegradable polymers, for example poly(lactic acid) polymers.
  • auxiliary substances preferably chosen from the group comprising carrier materials, fillers, solvents, diluents, wetting agents, emulsifiers, dyestuffs, preservatives, disintegrating agents, lubricants, salts for influencing the osmotic pressure, buffer substances, aromas and/or binders, can be used for the preparation of the medicaments.
  • the compounds according to the invention can be prepared by a process comprising the following steps: a) reacting 5,6,7,8-tetrahydroquinoxalin-5-ol with a protection agent X-PG in the presence of a base to introduce a protecting group PG at the alcohol function, wherein X is a suitable leaving group; b) catalytically hydrogenating the PG protected 5,6,7, 8-tetrahydroquinoxalin-5-ol obtained in step a) under stereoselective reduction of the pyrazine ring to obtain PG protected cis-cis 5-hydroxy-decahydroquinoxaline; c) reacting the PG protected cis-cis 5-hydroxy-decahydroquinoxaline obtained in step b) with a reagent X-R 1 to regioselectively introduce the substituent R 1 at the 1-N atom of the cis-cis 5-hydroxy-decahydroquinoxaline, wherein X is a suitable leaving group;
  • the process further comprises the step of separating the compound of formula (1) from its enantiomeric (4aR,5S,8aS) form.
  • the separation of the enantiomers can be carried out by known methods, in particular chromatography methods, preferably by means of high performance liquid chromatography (HPLC) or column chromatography or flash chromatography (FC), even more preferably by chiral chromatography methods, in particular chiral high performance liquid chromatography.
  • the separation of the enantiomers can also be carried out by reaction of a racemic mixture of an organic acid with a pure enantiomer of an acid.
  • the diastereomeric salts formed can be separated by fractional crystallization.
  • the splitting of the racemate is preferably carried out by reacting the racemate with an enantiomerically pure acid.
  • the separation is then carried out by fractional recrystallization or chromatography methods, it being possible for the methods to be combined and carried out several times.
  • the compound of formula (1) may be obtained in enantiomerically pure (4aS,5R,8aR) form by the process described above when subjecting enantiomerically pure (S)-5, 6,7,8- tetrahydroquinoxalin-5-ol to the reaction steps a) to g).
  • (S)-5,6,7,8-tetrahydroquinoxalin-5-ol may be obtained according to the invention by
  • step (a2) subjecting the ketone obtained in step (al) to an asymmetric hydrogen transfer reaction using a hydrogenation agent and a chiral catalyst to provide for enantiomerically pure (S)-5,6,7,8-tetrahydroquinoxalin-5-ol.
  • the compounds of formula (1) obtained may be converted to pharmaceutically acceptable salts by reaction with the corresponding acid in a common way.
  • the alcohol function in benzylic position can be protected with a bulky protecting group PG by reaction with a reagent X-PG such as tert-butyldimethylsilyl trifluoromethanesulfonate in the presence of a base like 2,6-lutidine in a solvent such as DCM.
  • a reagent X-PG such as tert-butyldimethylsilyl trifluoromethanesulfonate
  • a base like 2,6-lutidine
  • a stereoselective reduction of the pyrazine ring can be achieved by hydrogenating the protected 5,6,7,8-tetrahydroquinoxalin-5-ol with 5 bar hydrogen in the presence of a catalyst like platinum dioxide in a solvent such as a mixture of acetic acid and methanol.
  • a tert-butyldimethylsilyl protecting group for example, can be removed by reaction with a reagent such as ammonium fluoride in a solvent like methanol at elevated temperature.
  • a reagent such as ammonium fluoride in a solvent like methanol at elevated temperature.
  • the ⁇ , ⁇ -aminoalcohol thus obtained is reacted with sulfuryl chloride in the presence of a base like triethylamine in an inert solvent such as DCM at reduced temperature to yield the corresponding 1,2,3- oxathiazolidine 2,2-dioxide.
  • the residue -NR 2 R 3 can be introduced by reacting optionally substituted 1,2,3-oxathiazolidine 2,2-dioxide with an amine HNR 2 R 3 in a solvent like acetonitrile at elevated temperature followed by treatment with an acid such as aqueous hydrochloric acid.
  • the reaction takes place under inversion of the stereogenic center. Therefore, a compound with cis,trans substitution, optionally substituted (4aRS,5SR,8aSR)-5- amino-octahydroquinoxaline, is obtained exclusively.
  • Acylation in 4-position can be performed by reacting optionally substituted (4aRS,5SR,8aSR)-5-amino- octahydroquinoxaline with a reagent Z-A-COC1 in a solvent like DCM with or without the presence of a base such as DIEA.
  • the target compounds can be used as such or being converted to pharmaceutically acceptable salts such as a hydrochloride by reacting the free base with the corresponding acid, e.g. hydrogen chloride in diethyl ether in a suitable solvent like DCM.
  • R 1 can be a protecting group, e.g. a Boc, Cbz, benzyl, allyl, Alloc group, which is orthogonal to PG and can be cleaved once the residues -NR 2 R 3 and -CO-A-Z have been introduced. Subsequent reaction with reagents X-R 1 as described above yields the target compounds.
  • Reaction Scheme 2 :
  • Enantiomerically pure, optionally substituted (4aS,5R,8aR)-octahydroquinoxalines with cis,trans stereochemistry can be obtained as shown in Reaction Scheme 2.
  • Racemic 5,6,7,8- tetrahydroquinoxalin-5-ol can be oxidized to the corresponding ketone with a reagent such as Dess-Martin periodinane in a suitable solvent like wet DCM.
  • the ketone is subjected to a asymmetric hydrogen transfer reaction with dichloro(p-cymene)ruthenium(II) dimer, (lS,2S)-N-p-tosyl-l,2-diphenylethylenediamine and triethylammonium formate in DMF to yield enantiomerically pure (S)-5,6,7,8-tetrahydroquinoxalin-5-ol.
  • the reaction can be carried out using borane DMS complex or boran THF complex in the presence of (R)-Me-CBS-oxazoborolidine in a solvent like THF. All following steps are performed as described above for the racemate.
  • Reaction Scheme 3 :
  • Optionally substituted benzyl-protected perhydroquinoxazoline can be deprotected by hydrogenation in the presence of a catalyst such as palladium on charcoal in the presence in a suitable solvent like a mixture of THF and aqueous hydrochloric acid.
  • a catalyst such as palladium on charcoal
  • a suitable solvent like a mixture of THF and aqueous hydrochloric acid.
  • Boc-protected perhydroquinoxazoline can be deprotected with trifluoroacetic acid in DCM.
  • reagents such as HCl in suitable solvents like dioxane, diethyl ether and THF may be applied.
  • Optionally substituted Cbz-protected perhydroquinoxazoline can be deprotected by hydrogenation in the presence of a catalyst such as palladium on charcoal in the presence in a suitable solvent like a THF or ethyl acetate.
  • a catalyst such as palladium on charcoal
  • a suitable solvent like a THF or ethyl acetate.
  • the unprotected compound can be obtained by reaction with an acid like trifluoroacetic acid in the presence of a reagent such as thioanisole.
  • R 1 is chosen from Q-Qo-acyl, C3-Cio-cycloacyl, phenylacyl, heteroarylacyl, C(O)COO(C 1 -C 10 -alk l) and C(O)-(CH 2 ) COO(C 1 -C 10 -a]k l).
  • Carbamates in which R 1 is selected from COO(Ci-Cio-alkyl), COO(aryl) and COO(C 3 -d 0 - cycloalkyl) can be obtained by reacting the starting material with the corresponding optionally substituted alkyl-, aryl- and cycloalkylchloroformates in an inert solvent such as DCM.
  • R 1 represents Ci-Cio-alkyl, phenylalkyl and heteroarylalkyl
  • the corresponding optionally substituted aldehydes can be subjected to a reductive amination reaction with optionally substituted [8- aminooctahydroquinoxalin-l(2H)-yl]ethanones to yield the alkylated compounds.
  • the reaction is performed in a suitable solvent like MeOH in the presence of a reducing agent like NaBH 3 CN with pH adjustment by concentrated acetic acid.
  • residues can also be introduced in an alkylation reaction using appropriate optionally substituted Ci-Cio-alkylhalogenides, C 3 -Cio-cycloalkylhalogenides, phenylalkylhalogenides and heteroarylalkylhalogenides.
  • Alkylation reactions can be conducted in a solvent like MeCN in the presence of a base such as NaHC0 3 or in a solvent like DCM or chloroform in the presence of a base such as DIEA.
  • NR R contains functional groups, these can be protected before R is introduced and deprotected in a subsequent reaction step.
  • LC system Agilent 1100; binary pump: Agilent G1312A; degasser; auto sampler; column heater.
  • Detector DAD Agilent G1315D, 210 nm and 220-320 nm
  • MSD system Agilent LC/MSD G6130B ESI (pos/neg) mass range: 100-800
  • Example 3 To a solution of Example 3 (527 mg) in dichloromethane (5 ml), trifluoroacetic acid (2.358 ml) was added. The reaction mixture was stirred at RT overnight. The reaction mixture was evaporated in vacuo and coevaporated with toluene and with CH 2 C1 2 (2 x). The residue was dissolved in CH 2 C1 2 and washed with 0.5N NaOH (aq.) and water. The CH 2 C1 2 layer was dried over Na 2 S0 4 , filtered and evaporated in vacuo.
  • Example 9 (31 mg) was dissolved in CH 2 CI 2 (3 ml) and washed with IN NaOH (aq., 2 ml). The organic layer was separated and concentrated in vacuo to yield the free amine. Enantiomers were separated using chiral preparative HPLC (OD column, flow rate: 18 mL/min, eluent heptane/EtOH 8:2 + 0.1% diethylamine). After concentration of the product fractions in vacuo, both enantiomers were lyophilized from acetonitrile/water (1:1) to give 9 mg of Example 12 (first peak) and 9 mg of its enantiomer (second peak). The ee for both enantiomers was >98%.
  • Human opiate ⁇ receptors expressed in CHO-Kl cells are used in modified Tris-HCl buffer pH 7.4. An 11 ⁇ g aliquot is incubated with 0.6 nM [ HJDiprenorphine for 60 minutes at 25°C. Nonspecific binding is estimated in the presence of 10 ⁇ naloxone. Membranes are filtered and washed, the filters are then counted to determine [ HJDiprenorphine specifically bound. Test compounds are screened at various concentrations (see e.g. Wang, J.B. FEBS Lett. 1994;338:217-222).
  • ⁇ Opioid receptor functional assay Human recombinant opiate ⁇ receptors stably expressed in CHO-Kl cells are used. Test compound and/or vehicle is preincubated with the membranes (0.016 mg/ml) and 3 mM GDP in modified HEPES pH 7.4 buffer for 20 minutes at 25°C and SPA beads are then added for another 60 minutes at 30°C. The reaction is initiated by 0.3 nM [ 35 S]GTP S for an additional 30 minute incubation period. Test compound-induced inhibition of 0.1 ⁇ DAMGO-induced increase of [ 35 S]GTP S binding response by 50 percent or more (>50%) indicates receptor antagonist activity. Compounds are screened at various concentrations.
  • IC 50 values are grouped in three classes: a ⁇ 10 nM; b > 10 nM and ⁇ 100 nM; c >100 nM and ⁇ 1 ⁇
  • Example GTPyS % inhibition functional (nM) assay at 1 ⁇ c 71 a 101 b 98 c 70 a 102 b 99 b 99 c 77 c 80 c 66 c 89 b 99 b 95 a 99 b 93 c 77 b 98 b 92 b 95 b 97 b 99 a 100 b 96 a 100 b 93 b 92 c 80 c 58 c 61 c 62 38 c 73
  • mice are challenged several times with oxazolone following an initial sensitization. Ear thickness is measured daily during the treatment period with topical application of the test compound (see e.g. Ottosen E.R. J. Med. Chem. 2003;46: 5651-5662). At the end of the study ear weight is determined. Ears are characterized histologically and by immunofluorescence. Gene expression was quantified (RT-qPCR).
  • E. Mouse model of topical arachidonic acid-induced ear inflammation Arachidonic acid in acetone is applied topically to the anterior and posterior surfaces of the right ear of mice. Test substances are similarly applied 30 minutes before and 15 minutes after arachidonic acid. Ear swelling is measured 1 h after application of arachidonic acid. Scratching activity is monitored for 1 h following the application of arachidonic acid. Ear weight and histology parameters are determined at the end of the study (see e.g. Chang J. Eur. J. Pharmacol. 1987;142: 197-205).
  • mice are intrathecally injected in a volume of 5 ⁇ , 10 min before the i.d. injection of chloroquine (100 ⁇ g/ 10 ⁇ ) in the rostral back. Following the i.d. cheek injection, mice are placed in an arena with a clear glass floor and videotaped from beneath for 30 min. Videotapes are reviewed by blinded investigators, who count the number of hindlimb scratch bouts.
  • test items are administered intravenously to Wistar rats. Blood samples are taken after 15 minutes and after 1 h following administration. Perfused brains are collected 1 h following administration of the test item. Brain and plasma concentrations are measured. Clinical signs are monitored 15 minutes and 1 h after dosing.
  • Macrogol-6-cetostearyl ether 1.50
  • Example 10 As a specific embodiment of an oral composition of a compound of the present invention, 21 mg of Example 10 is formulated with sufficient finely divided lactose to provide a total amount of 580 to 590 mg to fill a size 0 hard gelatine capsule.
  • Example 12 As another specific embodiment of an oral composition of a compound of the present invention, 20 mg of Example 12 is formulated with sufficient finely divided lactose to provide a total amount of 580 to 590 mg to fill a size 0 hard gelatine capsule.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Rheumatology (AREA)
  • General Chemical & Material Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Pain & Pain Management (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)

Abstract

The present invention relates to perhydroquinoxaline compounds according to the general formula (1), their use as a medicament, in particular as analgesic, antipruritic antiinflammatory agents, and their preparation.

Description

PERHYDROQUINOXALINE DERIVATIVES
The present invention relates to perhydroquinoxaline derivatives and medicaments containing perhydroquinoxaline derivatives.
Treatment of pain is of great importance in medicine. Analgesic agents as a rule act by activating opioid receptors. Conventional opioids, such as morphine, are thus opioid analgesics which are often employed in clinical pain therapy because of their potent analgesic action. These activate the μ receptor. However, undesirable side effects of such pain therapy are sometimes considerable centrally mediated side effects, such as respiratory depression, vomiting and bradycardia. Possible psycho-dependencies are furthermore a disadvantage.
In view of the great importance of opioids in treating different types of pain and diseases associated with pain, there is a great need for new active compounds suitable to treat side effects of opioid adminstration (commonly also called "(analgesic) opioid induced side effects").
WO2009/080745 relates to perhydroquinoxaline derivatives useful as analgesic agents. The invention was based on the object to provide novel compounds which can be used as pharmaceutical active compounds, in particular for treating and/or preventing analgesic opioid induced side effects.
This object is achieved by the provision of perhydroquinoxaline compounds according to the general formula (I) as shown below or a solvate or hydrate thereof or a pharmaceutically acceptable salt thereof:
Figure imgf000002_0001
wherein:
R1 is chosen from the group comprising H; Ci-Cio-alkyl; C3-Cio-cycloalkyl; (COO(Ci-Cio-alkyl);
phenylalkyl with Ci-C6-alkyl, wherein the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising halogen, Ci-C6- alkyloxy, NH2, NH(C C5-alkyl), N(C C5-alkyl)2, OH, S02(CrC5-alkyl), SO(C C5-alkyl), CF3, CN, N02, S02N(Ci-C5-alkyl)2, S02NH2, S02NH(Ci-C5-alkyl), S02NH(aryl), S02NH(phenyl) and/or S02NH(heteroaryl);
Ci-Cio-acyl; heterocyclylacyl containing one, two, three or four hetero atoms chosen from the group comprising NH, O and/or S; phenylacyl, wherein the acyl radical is a Ci-C6-acyl radical and the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising halogen, Ci-C6-alkyloxy, COO(Ci-C6- alkyl), NH2, NH(Ci-C5-alkyl), N(Ci-C5-alkyl)2, CONH2, CONH(Ci-C6-alkyl), CON(Ci-C6- alkyl)2, OH, S02(Ci-C5-alkyl), SO(Ci-C5-alkyl), CF3, CN, N02, S02N(Ci-C5-alkyl)2, S02NH2, S02NH(C C5-alkyl), S02NH(aryl), S02NH(phenyl) and/or S02NH(heteroaryl);
mono-, bi- or tricyclic heteroaryl containing one, two, three or four hetero atoms chosen from the group comprising N, O and/or S;
mono-, bi- or tricyclic heteroarylalkyl containing one, two, three or four hetero atoms chosen from the group comprising N, O and/or S, wherein the alkyl radical is a Ci-C6 alkyl radical;
mono-, bi- or tricyclic heteroarylacyl containing one, two, three or four hetero atoms chosen from the group comprising N, O and/or S, wherein the acyl radical is a Ci-C6- acyl radical and the heteroaryl radical can be substituted by one or more identical or different groups chosen from the group comprising halogen, Ci-C6-alkyloxy, COO(Ci-C6-alkyl), NH2, NH(C C5-alkyl), N(CrC5-alkyl)2, CONH2, CONH(C C6-alkyl), CON(C C6-alkyl)2, OH, CF3, CN, N02, and/or S02NH2;
mono-, bi- or tricyclic (heteroaryl) alkenylacyl containing one, two, three or four hetero atoms chosen from the group comprising N, O and/or S, wherein the acyl radical is a Ci-C6-acyl radical and the alkenyl radical is a C2-C6-alkenyl radical;
C(0)NH(C Cio-alkyl); C(O)N(C1-C10-alk l)2, wherein the two alkyl radicals may form a saturated substituted or unsubstituted ring with the N atom; C(0)NH(aryl); C(0)NH(benzyl); C(O)(C3-Ci0-cycloalkyl); COO(aryl); COO(benzyl); COO(C3-Ci0- cycloalkyl);
(CH2)g-COOH, wherein g is 1, 2, 3 or 4; (CH2)h-COO(Ci-C6-alkyl), wherein h is 1, 2, 3 or 4; (CH2)i-CONH2, wherein i is 1, 2, 3 or 4;
C(0)NH-(CH2)j-COOH, wherein j is 0, 1, 2, 3 or 4; C(0)NH-(CH2)k-COO(Ci-
C6-alkyl), wherein k is 0, 1, 2, 3 or 4; C(0)NH-(CH2)i-CONH2, wherein 1 is 0, 1, 2, 3 or 4;
COO-(CH2)m-COOH, wherein m is 0, 1, 2, 3 or 4; COO-(CH2)n-COO(C C10- alkyl), wherein n is 0, 1, 2, 3 or 4; COO-(CH2)p-C(0)NH2, wherein p is 0, 1, 2, 3 or 4; C(O)- (CH2)q-COOH, wherein q is 0, 1, 2, 3 or 4; C(O)-(CH2)r-COO(Ci-Ci0-alkyl), wherein r is 0, 1, 2, 3 or 4; C(0)-(CH2)s-C(0)NH2, wherein s is 0, 1, 2, 3 or 4; C(0)-(CH2)t-C(0)NH(C1-C6- alkyl), wherein t is 0, 1, 2, 3 or 4; C(0)-(CH2)u-C(0)N(C C6-alkyl)2, wherein u is 0, 1, 2, 3 or 4;
C(0)-(CH2)v-NH2, wherein v is 0, 1, 2, 3 or 4; C(0)-(CH2)w-OR', wherein w is 0, 1, 2, 3 or 4 and R' is H or C C6-acyl; C(0)-(CH2)x-C(0)NH-(CH2)yC(0)NH2, wherein x is 0, 1, 2 or 3 and wherein y is 0, 1, 2 or 3;
S02(Ci-C6-alkyl); S02-(CH2)z-heteroaryl, wherein z is 0, 1, 2 or 3; S02(CH2)a- heterocyclyl, wherein a is 0, 1, 2 or 3 and wherein the heterocyclyl residue may be substituted by one or more identical or different substituents chosen from the group comprising halogen, OH, CN, oxo and/or Ci-C6-alkoxy; S02N(Ci-C6-alkyl)2 or S02NH(Ci-C6-alkyl), wherein the alkyl radical can be substituted by halogen, Ci-C4-alkoxy and/or OH; S02NH(C3-C6- cycloalkyl); S02NH-C(0)0(C1-C6-alkyl);
R 2 , R 3 are in each case identical or independent of each other and are chosen from the group comprising H; Ci-Cio-alkyl; C3-Cio-cycloalkyl,
or
R 2 and R 3 form, together with the nitrogen to which they are bonded, a saturated or unsaturated 3- to 8-membered N-heterocycle, wherein this can be substituted by one or more identical or different groups chosen from the group comprising halogen, OH, Cp C4-alkyloxy, COOH, COO(C C10-alkyl), CONH2, CONH(C C10-alkyl), CON(C C10- alkyl)2, CN, and/or 0-C(0)(Ci-C6 alkyl); A is chosen from the group comprising (CH2)b, wherein b is 0, 1, 2, 3, 4, 5, or 6;
C2-C5 alkylene, which can be substituted by at least one C1-C3 alkyl radical; O; S; NH and/or aryl; Z is chosen from the group comprising H; NH2; COOH; COO(Ci-Cs-alkyl);
CH(NH2)COOH; Ci-C6-acyl;
phenyl, which can be substituted by one or more identical or different groups chosen from the group comprising halogen, C C5-alkyl, C C5-alkoxy, NH2, NH(C C5-alkyl), N(C C5- alkyl)2, OH, S02(Ci-C5-alkyl), SO(Ci-C5-alkyl), CF3, CN, N02, S02N(Ci-C5-alkyl)2, SO2NH2, S02NH(Ci-C5-alkyl), S02NH(aryl), S02NH(phenyl) and/or S02NH(heteroaryl), wherein the substituents may form a ring;
a mono- or bicyclic aryl or heteroaryl containing one or two hetero atoms chosen from the group comprising N, O and/or S, wherein the aryl or heteroaryl group can be substituted by one or more identical or different groups chosen from the group comprising halogen, Ci-C4-alkoxy, NH2, NH(Ci-C5-alkyl), N(Ci-C5-alkyl)2, OH, S02(Ci-C5-alkyl), SO(Ci-C5-alkyl), CF3, CN, N02, S02N(Ci-C5-alkyl)2, S02NH2, S02NH(Ci-C5-alkyl), S02NH(aryl), S02NH(phenyl) and/or S02NH(heteroaryl).
The perhydroquinoxaline compounds of formula (1) according to the invention are named following the IUPAC nomenclature. In addition, the stereochemistry of the compounds of formula (1) follow the CIP nomenclature (Cahn-Ingold-Prelog) and may be specified as (4aS,5R,8aR) as long as the radical R1 has the highest priority. Alternatively, if the priority under IUPAC of the C(0)AZ moiety is higher than the one of R1 the stereochemistry is defined as (4aR,8R,8aS). In the following general description, in the absence of any definition to the contrary, whenever the stereochemistry of the compounds of formula (1) in general is referred to, it is assumed that the radical R1 has the highest priority and, thus, the (4aS,5R,8aR) definition applies. Consequently, the enantiomer of the compounds of formula (1) is referred to as the (4aR,5S,8aS) form. It has been found, surprisingly, that the compounds according to the invention have an improved action in treating and/or preventing analgesic opioid induced side effects and diseases having the same or similar symptoms (i.e. the same or a similar pathology). Without wishing to be bound by a particular theory, it is assumed that not only the perhydroquinoxaline ring structure of the compounds according to the invention has a considerable influence on the advantageous properties of the compounds, but in particular the specific stereochemistry in the perhydroquinoxaline ring structure as shown in formula (1). In particular, the compounds according to the invention have been shown to act as μ opioid receptor antagonists. This action is assumed to be responsible for the pharmaceutical efficacy.
In the context of the present invention, unless stated otherwise, the term "heteroaryl" is to be understood as meaning mono-, bi- or tricyclic heteroaryl containing one, two, three or four hetero atoms chosen from the group comprising N, O and/or S.
Preferred heteroaryl radicals are chosen from the group comprising pyridinyl, pyrimidinyl, pyrazinyl, triazolyl, pyridazinyl, 1,3,5-triazinyl, quinolyl, isoquinolyl, quinolinyl, isoquinolinyl, quinoxalinyl, imidazolyl, pyrazolyl, benzimidazolyl, benzooxazolyl, benzothiazolyl, thiazolyl, oxazolyl, isoxazolyl, oxazolidinyl, pyrrolyl, carbazolyl, indolyl, isoindolyl, furyl, benzofuryl, benzofuranyl, 1,3-benzodioxolyl, thienyl and/or benzothienyl.
The term "Ci-Cio-alkyl" according to the invention includes, unless stated otherwise, straight- chain, branched or cyclic alkyl groups, preferably chosen from the group comprising methyl, ethyl, n-/i-propyl, n-/i-/tert-butyl, pentyl, neopentyl, hexyl, heptyl, octyl, nonyl and/or decyl.
The term "heterocyclyl" according to the invention includes saturated, mono- or diunsaturated cyclic alkyl radicals having 3 to 10 carbon atoms that contain one, two, three or four hetero atoms chosen from the group comprising NH, O and/or S. Ci-C6-alkoxy groups according to the invention are preferably chosen from the group comprising methoxy, ethoxy, linear or branched propoxy and/or butoxy. The term "halogen" according to the invention includes fluorine, chlorine, bromine and iodine, fluorine or chlorine being preferred, in particular chlorine.
The term "aryl" according to the invention includes aromatic radicals having 6 to 20 carbon atoms, preferably phenyl, naphthyl, indenyl, and biphenyl. The term "aryl" also includes carbocycles.
In the context of the present invention, if not indicated otherwise, the term "acyl" means "Cr Cio-acyl", namely including the groups HC(O)- (formyl) and (Ci-Cc))-C(0)-, wherein (C1-C9) means linear, branched or cyclic alkyl or alkenyl groups. HC(O)- (formyl) and CH3-C(0)- (acetyl) are preferred.
In preferred embodiments of the compounds of formula (1) the residues R 1 , R 2 , R 3 and Z are as defined in the dependent claims 2 to 5.
Preferably in the compound according general formula (1)
R1 is chosen from the group comprising H; Ci-C3-alkyl; COO(Ci-C4-alkyl);
benzyl;
Ci-C4-acyl; C(0)(C4-C6-cycloalkyl); heterocyclylacyl containing NH or O in the ring; phenylacyl, wherein the acyl radical is a Ci-acyl radical and the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(C C3-alkyl) and CONH2;
mono-cyclic heteroaryl containing one hetero atom chosen from the group of
N, O and S;
mono-cyclic heteroarylalkyl containing one or two hetero atom chosen from the group of N, O and S, wherein the alkyl radical is a C1-C3 alkyl radical;
mono-cyclic heteroarylacyl containing one or two hetero atoms chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the heteroaryl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(Ci-C3-alkyl) and CONH2;
mono-cyclic (heteroaryl) alkenylacyl containing one hetero atom chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the alkenyl radical is a C2-C4- alkenyl radical; C(0)NH(Ci-C3-alkyl); C(0)N(Ci-C3-alkyl)2, wherein the two alkyl radicals may form a saturated halogen substituted or unsubstituted ring with the N atom; C(0)NH(phenyl); C(0)NH(benzyl); C(0)(C3-C6-cycloalkyl); COO(benzyl);
(CH2)g-COOH, wherein g is 1, 2, 3 or 4; (CH2)h-COO(C C6-alkyl), wherein h is 1, 2, 3 or 4; (CH2)i-CONH2, wherein i is 1, 2, 3 or 4;
C(0)NH-(CH2)j-COOH, wherein j is 0 or 1; C(0)NH-(CH2)k-COO(Ci-C3- alkyl), wherein k is 0 or 1; C(0)NH-(CH2)rCONH2, wherein 1 is 0 or 1;
COO-(CH2)m-COOH, wherein m is 0 or 1; COO-(CH2)n-COO(C C3-alkyl), wherein n is 0 or 1; COO-(CH2)p-C(0)NH2, wherein p is 0 or 1; C(0)-(CH2)q-COOH, wherein q is 0 or 1; C(0)-(CH2)r-COO(Ci-C3-alkyl), wherein r is 0 or 1; C(0)-(CH2)s- C(0)NH2, wherein s is 0 or 1; C(0)-(CH2)t-C(0)NH(C C3-alkyl), wherein t is 0 or 1; C(O)- (CH2)u-C(0)N(C C3-alkyl)2, wherein u is 0 or 1;
C(0)-(CH2)v-NH2, wherein v is 0 or 1 ; C(0)-(CH2)w-OR', wherein w is 0 or 1 and R' is H or C acyl; C(0)-(CH2)x-C(0)NH-(CH2)yC(0)NH2, wherein x is 0 or 1 and wherein y is 0 or 1 ;
S02(Ci-C6-alkyl); S02-(CH2)z-heteroaryl, wherein z is 0 or 1; S02(CH2)a- heterocyclyl, wherein a is 0 or 1, wherein the heteroatoms are O, N, and/or S and wherein the heterocyclyl residue may be substituted by one or more identical or different substituents chosen from the group comprising F, CI, OH, CN, oxo and/or Ci-C3-alkoxy; S02N(Ci-C3- alkyl)2 or S02NH(Ci-C3-alkyl), wherein the alkyl radical can be substituted by F, CI, Ci-C3- alkoxy and/or OH; S02NH(C3-C6-cycloalkyl); S02NH-C(0)0(C C3- alkyl);
R 2 , R 3 are identical or different and are chosen from the group comprising H, methyl, ethyl, n-propyl, and i-propyl,
or
R 2 and R 3 form, together with the nitrogen to which they are bonded, a saturated or mono-unsaturated 4- to 6-membered N-heterocycle, wherein this can be substituted by one or more identical or different groups chosen from the group comprising F, CI, OH, CONH2, CN, and/or 0-C(0)(C C3 alkyl);
A is (CH2)b, wherein b is 1;
Z is chosen from the group comprising phenyl, which can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C3-alkyl, Ci-C3-alkoxy, OH, CF3, and N02, wherein two OH substituents may be connected by an ether bridge to form a ring or wherein two Ci-C3-alkyl groups may be connected to form a saturated ring; and
a mono- or bicyclic aryl or heteroaryl containing one hetero atom chosen from the group of N and S, wherein the aryl or heteroaryl group can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C3-alkyl, Ci-C3- alkoxy, OH, CF3, and N02. More preferably in the compound according to general formula (1):
R1 is chosen from the group consisting of
Ci-acyl (formyl); heterocyclylacyl containing NH or O in the ring; phenylacyl, wherein the acyl radical is a Ci-acyl radical and the phenyl radical is substituted by one or more of COO(C C3-alkyl) and CONH2;
mono-cyclic heteroarylacyl containing one or two hetero atoms chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the heteroaryl radical is substituted by one or more of COO(Ci-C3-alkyl) and CONH2;
mono-cyclic (heteroaryl) alkenylacyl containing one hetero atom chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the alkenyl radical is a C2-C4- alkenyl radical;
C(0)NH(C C3-alkyl); C(0)N(C C3-alkyl)2, wherein the two alkyl radicals form a saturated halogen substituted or unsubstituted ring with the N atom; C(0)NH (phenyl); C(0)NH(benzyl); COO(benzyl);
(CH2)g-COOH, wherein g is 1, 2, 3 or 4; (CH2)h-COO(Ci-C6-alkyl), wherein h is 1, 2, 3 or 4; (CH2)i-CONH2, wherein i is 1, 2, 3 or 4;
C(0)NH-(CH2)j-COOH, wherein j is 0 or 1; C(0)NH-(CH2)k-COO(C C3- alkyl), wherein k is 0 or 1; C(0)NH-(CH2)rCONH2, wherein 1 is 0 or 1;
COO-(CH2)m-COOH, wherein m is 0 or 1; COO-(CH2)n-COO(C C3-alkyl), wherein n is 0 or 1; COO-(CH2)p-C(0)NH2, wherein p is 0 or 1; C(0)-(CH2)s-C(0)NH2, wherein s is 0 or 1; C(0)-(CH2)t-C(0)NH(Ci-C3-alkyl), wherein t is 0 or 1; C(0)-(CH2)u- C(0)N(Ci-C3-alkyl)2, wherein u is 0 or 1;
C(0)-(CH2)v-NH2, wherein v is 1 ; C(0)-(CH2)w-OR', wherein w is 1 and R' is
H or Ci-acyl; S02(Ci-C6-alkyl); S02-(CH2)z-heteroaryl, wherein z is 0 or 1; S02(CH2)a- heterocyclyl, wherein a is 0 or 1, wherein the heteroatoms are O, N, and/or S and wherein the heterocyclyl residue may be substituted by one or more identical or different substituents chosen from the group comprising F, CI, OH, CN, oxo and/or Ci-C3-alkoxy; S02N(Ci-C3- alkyl)2 or S02NH(Ci-C3-alkyl), wherein the alkyl radical can be substituted by F, CI, C1-C3- alkoxy and/or OH; S02NH(C3-C6-cycloalkyl); S02NH-C(0)0(Ci-C3- alkyl);
R 2 , R 3 are identical or different and are chosen from the group comprising H, methyl, ethyl, n-propyl, and i-propyl,
or
R 2 and R 3 form, together with the nitrogen to which they are bonded, a saturated or mono-unsaturated 4- to 6-membered N-heterocycle, wherein this can be substituted by one or more identical or different groups chosen from the group comprising F, CI, OH, CONH2, CN, and/or 0-C(0)(C C3 alkyl);
A is (CH2)b, wherein b is 1;
Z is chosen from the group comprising
phenyl, which can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C3-alkyl, Ci-C3-alkoxy, OH, CF3, and N02, wherein two OH substituents may be connected by an ether bridge to form a ring or wherein two C1-C3- alkyl groups may be connected to form a saturated ring; and
a mono- or bicyclic aryl or heteroaryl containing one hetero atom chosen from the group of N and S, wherein the aryl or heteroaryl group can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C3-alkyl, C1-C3- alkoxy, OH, CF3, and N02.
Particularly preferably in the compound according to general formula (1):
R1 is chosen from the group comprising H; Ci-C3-alkyl; COO(Ci-C4-alkyl);
benzyl;
Ci-C4-acyl; C(0)(C4-C6-cycloalkyl); heterocyclylacyl containing NH or O in the ring; phenylacyl, wherein the acyl radical is a Ci-acyl radical and the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(Ci-C3-alkyl) and CONH2;
mono-cyclic heteroaryl containing one hetero atom chosen from the group of
N, O and S;
mono-cyclic heteroarylalkyl containing one or two hetero atom chosen from the group of N, O and S, wherein the alkyl radical is a Ci-C3 alkyl radical;
mono-cyclic heteroarylacyl containing one or two hetero atoms chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the heteroaryl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(Ci-C3-alkyl) and CONH2;
mono-cyclic (heteroaryl) alkenylacyl containing one hetero atom chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the alkenyl radical is a C2-C4- alkenyl radical;
C(0)NH(C C3-alkyl); C(0)N(C C3-alkyl)2, wherein the two alkyl radicals may form a saturated halogen substituted or unsubstituted ring with the N atom; C(0)NH(phenyl); C(0)NH(benzyl); C(0)(C3-C6-cycloalkyl); COO(benzyl);
(CH2)g-COOH, wherein g is 1, 2, 3 or 4; (CH2)h-COO(C C6-alkyl), wherein h is 1, 2, 3 or 4; (CH2)i-CONH2, wherein i is 1, 2, 3 or 4;
C(0)NH-(CH2)j-COOH, wherein j is 0 or 1; C(0)NH-(CH2)k-COO(Ci-C3- alkyl), wherein k is 0 or 1 ; C(0)NH-(CH2)i-CONH2, wherein 1 is 0 or 1 ;
COO-(CH2)m-COOH, wherein m is 0 or 1; COO-(CH2)n-COO(C C3-alkyl), wherein n is 0 or 1; COO-(CH2)p-C(0)NH2, wherein p is 0 or 1; C(0)-(CH2)q-COOH, wherein q is 0 or 1; C(0)-(CH2)r-COO(Ci-C3-alkyl), wherein r is 0 or 1; C(0)-(CH2)s- C(0)NH2, wherein s is 0 or 1; C(0)-(CH2)t-C(0)NH(Ci-C3-alkyl), wherein t is 0 or 1; C(O)- (CH2)u-C(0)N(Ci-C3-alkyl)2, wherein u is 0 or 1 ;
C(0)-(CH2)v-NH2, wherein v is 0 or 1 ; C(0)-(CH2)w-OR', wherein w is 0 or 1 and R' is H or C acyl; C(0)-(CH2)x-C(0)NH-(CH2)yC(0)NH2, wherein x is 0 or 1 and wherein y is 0 or 1 ;
S02(C C6-alkyl); S02-(CH2)z-heteroaryl, wherein z is 0 or 1; S02(CH2)a- heterocyclyl, wherein a is 0 or 1, wherein the heteroatoms are O, N, and/or S and wherein the heterocyclyl residue may be substituted by one or more identical or different substituents chosen from the group comprising F, CI, OH, CN, oxo and/or Ci-C3-alkoxy; S02N(Ci-C3- alkyl)2 or S02NH(Ci-C3-alkyl), wherein the alkyl radical can be substituted by F, CI, C1-C3- alkoxy and/or OH; S02NH(C3-C6-cycloalkyl); S02NH-C(0)0(Ci-C3- alkyl);
2 3
R and R form, together with the nitrogen to which they are bonded, a mono- unsaturated 6-membered N-heterocycle, that may be substituted by one or more of F, CI, OH, CONH2, CN, and/or 0-C(0)(Ci-C3 alkyl);
A is (CH2)b, wherein b is 1; Z is chosen from the group comprising
phenyl, which can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C3-alkyl, Ci-C3-alkoxy, OH, CF3, and N02, wherein two OH substituents may be connected by an ether bridge to form a ring or wherein two Ci-C3- alkyl groups may be connected to form a saturated ring; and
a mono- or bicyclic aryl or heteroaryl containing one hetero atom chosen from the group of N and S, wherein the aryl or heteroaryl group can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C3-alkyl, Ci-C3- alkoxy, OH, CF3, and N02. Particularly preferably in the compound according to general formula (1):
R1 is chosen from the group comprising H; Ci-C3-alkyl; COO(Ci-C4-alkyl);
benzyl;
Ci-C4-acyl; C(0)(C4-C6-cycloalkyl); heterocyclylacyl containing NH or O in the ring; phenylacyl, wherein the acyl radical is a Ci-acyl radical and the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(C C3-alkyl) and CONH2;
mono-cyclic heteroaryl containing one hetero atom chosen from the group of
N, O and S;
mono-cyclic heteroarylalkyl containing one or two hetero atom chosen from the group of N, O and S, wherein the alkyl radical is a Ci-C3 alkyl radical;
mono-cyclic heteroarylacyl containing one or two hetero atoms chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the heteroaryl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(Ci-C3-alkyl) and CONH2;
mono-cyclic (heteroaryl)alkenylacyl containing one hetero atom chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the alkenyl radical is a C2-C4- alkenyl radical;
C(0)NH(Ci-C3-alkyl); C(0)N(Ci-C3-alkyl)2, wherein the two alkyl radicals may form a saturated halogen substituted or unsubstituted ring with the N atom; C(0)NH(phenyl); C(0)NH(benzyl); C(0)(C3-C6-cycloalkyl); COO(benzyl);
(CH2)g-COOH, wherein g is 1, 2, 3 or 4; (CH2)h-COO(Ci-C6-alkyl), wherein h is 1, 2, 3 or 4; (CH2)i-CONH2, wherein i is 1, 2, 3 or 4;
C(0)NH-(CH2)j-COOH, wherein j is 0 or 1; C(0)NH-(CH2)k-COO(C C3- alkyl), wherein k is 0 or 1; C(0)NH-(CH2)rCONH2, wherein 1 is 0 or 1;
COO-(CH2)m-COOH, wherein m is 0 or 1; COO-(CH2)n-COO(C C3-alkyl), wherein n is 0 or 1; COO-(CH2)p-C(0)NH2, wherein p is 0 or 1; C(0)-(CH2)q-COOH, wherein q is 0 or 1; C(0)-(CH2)r-COO(Ci-C3-alkyl), wherein r is 0 or 1; C(0)-(CH2)s- C(0)NH2, wherein s is 0 or 1; C(0)-(CH2)t-C(0)NH(Ci-C3-alkyl), wherein t is 0 or 1; C(O)- (CH2)u-C(0)N(C C3-alkyl)2, wherein u is 0 or 1;
C(0)-(CH2)v-NH2, wherein v is 0 or 1 ; C(0)-(CH2)w-OR', wherein w is 0 or 1 and R' is H or Ci-acyl; C(0)-(CH2)x-C(0)NH-(CH2)yC(0)NH2, wherein x is 0 or 1 and wherein y is 0 or 1 ;
S02(C C6-alkyl); S02-(CH2)z-heteroaryl, wherein z is 0 or 1; S02(CH2)a- heterocyclyl, wherein a is 0 or 1, wherein the heteroatoms are O, N, and/or S and wherein the heterocyclyl residue may be substituted by one or more identical or different substituents chosen from the group comprising F, CI, OH, CN, oxo and/or Ci-C3-alkoxy; S02N(Ci-C3- alkyl)2 or S02NH(Ci-C3-alkyl), wherein the alkyl radical can be substituted by F, CI, Ci-C3- alkoxy and/or OH; S02NH(C3-C6-cycloalkyl); S02NH-C(0)0(C C3- alkyl);
R 2 , R 3 are identical or different and are chosen from the group comprising H, methyl, ethyl, n-propyl, and i-propyl,
or
R 2 and R 3 form, together with the nitrogen to which they are bonded, a saturated or mono-unsaturated 4- to 6-membered N-heterocycle, wherein this can be substituted by one or more identical or different groups chosen from the group comprising F, CI, OH, CONH2, CN, and/or 0-C(0)(Ci-C3 alkyl);
A is (CH2)b, wherein b is 1;
Z is either a tetrahydronaphthyl or a 2,3-dihydrobenzo-l,4-dioxinyl residue, optionally substituted by one or more of F, CI, Ci-C3-alkyl, Ci-C3-alkoxy, OH, CF3, and N02.
Particularly preferred radicals R1 according to the invention are as follows:
Figure imgf000014_0001
Particularly preferred radicals NR 2 R 3 according to the invention are as follows:
Figure imgf000015_0001
Particularly preferred radicals Z according to the invention are as follows:
Figure imgf000015_0002
Without being bound by a particular theory, it is assumed that the action of the compounds according to the invention is not only based on the steric action of the perhydroquinoxaline group, in particular in combination with the structural element R1, but even more on the specific cis-trans stereochemistry and the (4aS,5R,8aR) form of the compounds as indicated in formula (1). Reference is made to the Biological Assay section of the application.
The compounds according to the invention can furthermore be used in the form of their acids or their bases or in the form of their salts, in particular the physiologically acceptable salts, or in the form of their solvates, in particular their hydrates.
The pharmaceutically acceptable salts can be base addition salts. These include salts of the compounds according to the invention with inorganic bases, such as alkali metal hydroxides, alkaline earth metal hydroxides, or with organic bases, such as mono-, di- or triethanolamine. Acid addition salts, in particular with inorganic acids, such as hydrochloric acid, sulfuric acid or phosphoric acid, or with suitable organic carboxylic or sulfonic acids, or with amino acids, can further advantageously be used.
Pharmaceutically acceptable salts of the compounds according to the invention are chosen, for example, from the group comprising chlorides, bromides, iodides, hydrochlorides, hydrobromides, sulfonates, methanesulfonates, sulfates, hydrogen sulfates, sulfites, hydrogen sulfites, phosphates, nitrates, methanoates, acetates, proprionates, lactates, citrates, glutarates, maleates, malonates, malates, succinates, tartrates, oxalates, fumarates, benzoates, p- toluenesulfonates and/or salts of amino acids, preferably the proteinogenic amino acids.
The compounds according to the invention are suitable for use as medicaments.
The compounds according to the invention can be used in particular for therapeutic and/or prophylactic treatment of side effects associated with opioid administration (opioid induced side effects) and diseases having the same or similar symptoms.
The side effects and/or diseases to be treated according to the invention preferably are selected from gastrointestinal dysfunction, inhibition of intestinal motility, constipation, GI sphincter constriction, nausea, emesis, biliary spasm, opioid bowel dysfunction, colic, dysphoria, pruritus, urinary retention, depression of respiration, papillary constriction, cardiovascular effects, chest wall rigidity and cough suppression, depression of stress response, and immune suppression associated with use of narcotic analgesia, or combinations thereof.
The side effects and/or diseases to be treated according to the invention may also be selected from irritable bowel syndrome, opioid-induced bowel dysfunction, colitis, post-operative or postpartum ileus, nausea and/or vomiting, decreased gastric motility and emptying, inhibition of the stomach, and small and/or large intestinal propulsion, increased amplitude of nonpropulsive segmental contractions, constriction of sphincter of Oddi, increased anal sphincter tone, impaired reflex relaxation with rectal distention, diminished gastric, biliary, pancreatic or intestinal secretions, increased absorption of water from bowel contents, gastro-esophageal reflux, gastroparesis, cramping, bloating, abdominal or epigastric pain and discomfort, constipation, idiopathic constipation, post-operative gastrointestinal dysfunction following abdominal surgery, and delayed absorption of orally administered medications or nutritive substances.
The compounds according to the invention may further be used as a medicament in the treatment of pain, in the treatment of inflammatory conditions such as inflammatory bowel syndrome, in the treatment of infectious diseases, in the treatment of diseases of the musculoskeletal system such as osteoporosis, arthritis, osteitis, periostitis, myopathies, treatment of autoimmune diseases and immune suppression, therapy of post-operative gastrointestinal dysfunction following abdominal surgery, idiopathic constipation, and ileus, and in the treatment of disorders such as cancers involving angiogenesis, chronic inflammation and/or chronic pain, sickle cell anemia, vascular wounds, and retinopathy.
The patients suffering from the diseases to be treated according to the invention are preferably those receiving acute opioid therapy, such as a patient suffering from post-operative gastrointestinal dysfunction receiving acute opioid administration, or a subject receiving opioids chronically such as an AIDS patient, a cancer patient, a cardiovascular patient; a subject receiving chronic opioid therapy for pain management; or a subject receiving opioid therapy for maintenance of opioid withdrawal. The compounds according to the invention can furthermore be used for treatment and/or prevention of pruritus, psoriasis, psoriatic arthritis, contact dermatitis, atopic eczema, scleroderma, systemic lupus erythematous, urticaria, lichen planus, lymphoma and/or allergies.
The compounds according to the invention or compositions containing these can be administered systemically or topically. Preferably, the compounds or compositions according to the invention are administered topically, in particular in the form of creams, ointments, plasters or tinctures.
In the context of the present invention, the term "prophylactic treatment" is understood as meaning in particular that the compounds according to the invention can be administered before symptoms of a disease occur or the risk of a disease exists.
The medicaments according to the invention may further comprise at least one opioid receptor agonist. Suitable are the opioids selected from the group consisting of alfentanil, anileridine, asimadoline, bremazocine, burprenorphine, butorphanol, codeine, CR845, dezocine, diacetylmorphine (heroin), dihydrocodeine, diphenoxylate, ethylmorphine, fedotozine, fentanyl, funaltrexamine, hydrocodone, hydromorphone, levallorphan, levomethadyl acetate, levomethadon. levorphanol. loperamide, meperidine ( pethidine), methadone, morphine. morphine-6-glucoronide, nalbuphine, nalorphine, nicomorphine, opium, oxycodone, oxymorphone, papavereturn, pentazocine, pethidin. piritramid. propiram, propoxyphene, remifentanyl, sufentanil, tilidine, trimebutine, and tramadol. More preferably the opioid is chosen from the group consisting of tramadol, pethidin. codein. piritramid. morphin, levomethadon. fentanyl. alfentanil.. remifentanyl and/or sufentanil.
The medicaments according to the invention may further comprise at least one steroidal antiinflammatory drug, preferably chosen from the group of hydrocortisone, hydrocortisone acetate, prednisolone, methylprednisolone, prednisone, betamethasone, hydrocortisone- 17- valerate, betamethasone valerate, betamethasone dipropionate, prednicarbate, clobetasone-17- butyrate flunisolide, fluticasone propionate, triamcinolone acetonide, beclomethasone dipropionate, budesonide and/or hydrocortisone- 17-butyrate and/or a nonsteroidal anti- inflammatory drug (NSAID), preferably chosen from the group of aspirin, ibuprofen, diclofenac and/or naproxen, and/or an antibiotic.
The compounds according to the invention can be administered according to conventional methods, for example orally, dermally, intranasally, transmucosally, pulmonally, enterally, buccally, rectally, intraurethral, aural, by inhalation, by means of injection, for example intravenously, parenterally, intraperitoneally, intradermally, subcutaneously, topically and/or intramuscularly and/or locally, for example on painful areas of the body. Oral administration is particularly preferred.
The compounds according to the invention can be used in particular for the preparation of medicaments by being brought into a suitable dosage form together with at least one carrier substance or auxiliary substance, for example in the form of injection solutions, drops, juices, syrups, sprays, suspensions, tablets, patches, capsules, plasters, suppositories, ointments, creams, lotions, gels, emulsions, aerosols or in multiparticulate form, for example in the form of pellets or granules.
Pharmaceutical dosage forms with delayed release (sustained release formulation) are furthermore preferred for oral administration of the compounds according to the invention. Examples of formulations with delayed release are sustained release matrix tablets, multilayered tablets, the coating of which can be, for example, constructed to be resistant to gastric juice, such as coatings based on shellac, sustained release capsules or formulations using biodegradable polymers, for example poly(lactic acid) polymers. Conventional physiologically acceptable pharmaceutical auxiliary substances, preferably chosen from the group comprising carrier materials, fillers, solvents, diluents, wetting agents, emulsifiers, dyestuffs, preservatives, disintegrating agents, lubricants, salts for influencing the osmotic pressure, buffer substances, aromas and/or binders, can be used for the preparation of the medicaments.
The compounds according to the invention can be prepared by a process comprising the following steps: a) reacting 5,6,7,8-tetrahydroquinoxalin-5-ol with a protection agent X-PG in the presence of a base to introduce a protecting group PG at the alcohol function, wherein X is a suitable leaving group; b) catalytically hydrogenating the PG protected 5,6,7, 8-tetrahydroquinoxalin-5-ol obtained in step a) under stereoselective reduction of the pyrazine ring to obtain PG protected cis-cis 5-hydroxy-decahydroquinoxaline; c) reacting the PG protected cis-cis 5-hydroxy-decahydroquinoxaline obtained in step b) with a reagent X-R1 to regioselectively introduce the substituent R1 at the 1-N atom of the cis-cis 5-hydroxy-decahydroquinoxaline, wherein X is a suitable leaving group; d) deprotecting the PG protected hydroxy group in the product obtained in step c) to provide for the corresponding α,β-aminoalcohol; e) reacting the α,β-aminoalcohol obtained in step d) with sulfuryl chloride in the presence of a base to provide for the corresponding 1,2,3-oxathiazolidine 2,2-dioxide; f) reacting the 1,2,3-oxathiazolidine 2,2-dioxide obtained in step e) with an amine HNR 2 R 3 , followed by treatment with an acid to introduce the residue -NR 2 R 3 under inversion of the stereogenic center to provide for cis,trans 5-amino-octahydroquinoxaline; g) reacting the cis,trans 5-amino-octahydroquinoxaline obtained in step f) with an activated species ZACOY, wherein Y is a suitable leaving group, preferably with an acid chloride Z-ACOC1, under acylation in 4-position to provide for the compound of formula (1).
By this reaction (shown in Reaction Scheme 1 below in more detail) a racemate comprising two enantiomers is formed, namely next to the (4aS,5R,8aR) form of formula (1) also the enantiomeric (4aR,5S,8aS) form is obtained. In a preferred embodiment of the invention the process further comprises the step of separating the compound of formula (1) from its enantiomeric (4aR,5S,8aS) form. The separation of the enantiomers can be carried out by known methods, in particular chromatography methods, preferably by means of high performance liquid chromatography (HPLC) or column chromatography or flash chromatography (FC), even more preferably by chiral chromatography methods, in particular chiral high performance liquid chromatography.
The separation of the enantiomers can also be carried out by reaction of a racemic mixture of an organic acid with a pure enantiomer of an acid. The diastereomeric salts formed can be separated by fractional crystallization. The splitting of the racemate is preferably carried out by reacting the racemate with an enantiomerically pure acid. The separation is then carried out by fractional recrystallization or chromatography methods, it being possible for the methods to be combined and carried out several times.
The compound of formula (1) may be obtained in enantiomerically pure (4aS,5R,8aR) form by the process described above when subjecting enantiomerically pure (S)-5, 6,7,8- tetrahydroquinoxalin-5-ol to the reaction steps a) to g). (S)-5,6,7,8-tetrahydroquinoxalin-5-ol may be obtained according to the invention by
(al) oxidizing 5,6,7,8-tetrahydroquinoxalin-5-ol to the corresponding ketone with an oxidizing agent;
(a2) subjecting the ketone obtained in step (al) to an asymmetric hydrogen transfer reaction using a hydrogenation agent and a chiral catalyst to provide for enantiomerically pure (S)-5,6,7,8-tetrahydroquinoxalin-5-ol.
This reaction is shown in Reaction Scheme 2 below in more detail. As the chiral catalyst dichloro(p-cymene)ruthenium(II) dimer with enantiomeric (lS,2S)-N-p- tosyl-l,2-diphenylethylenediamine or enantiomeric (R)-Me-CBS-oxazoborolidine as the ligand may be used.
Finally, the compounds of formula (1) obtained may be converted to pharmaceutically acceptable salts by reaction with the corresponding acid in a common way.
In the following the preparation of the compounds of formula (1) according to the present invention and of related reference compounds is described in more detail. In the schemes, preparations and examples below, various reagent symbols and abbreviations have the following meanings:
Alloc Allyloxycarbonyl
Boc tert-butoxycarbonyl
Bn benzyl
Cbz benzyloxycarbonyl
DCM dichloromethane
DIEA ethyl-diisopropylamine
DMAP 4-dimethylaminopyridine
DMF N,N-dimethylformamide
DMS dimethylsulfide
DMSO dimethyl sulfoxide
ee enantiomeric excess
Et20 diethyl ether
EtOAc ethyl acetate
EtOH ethanol
h hour(s)
HOAc acetic acid
m/z mass-to-charge ratio
mCPBA 3-chloroperbenzoic acid
min minute(s)
NBS N-bromosuccinimide
MeCN acetonitrile
MeOH methanol
mp melting point
MW molecular weight
PG protecting group
Ph phenyl
RT room temperature
T temperature
TBDMS tert-butyldimethylsiliyl
TEA triethylamine TFA trifluoroacetic acid
TFAA trifluoroacetic acid anhydride
THF tetrahydrofuran
TLC thin layer chromatography
tR (min) HPLC retention time
Reaction Scheme 1:
Synthesis of perhydroquinoxalines with cis,trans stereochemistry (racemates)
Figure imgf000023_0001
rac. R rac. rac.
Figure imgf000023_0002
rac.
Optionally substituted perhydroquinoxalines with cis,trans stereochemistry can be obtained as shown in Reaction Scheme 1. 5,6,7,8-Tetrahydroquinoxaline can be oxidized with a peracid such as meta-chloroperbenzoic acid in a solvent like DCM to yield the corresponding N- oxides. Acylation with a reagent such as trifluoroacetic anhydride in a solvent like DCM followed by treatment with a base like lithium hydroxide in a mixture of water and DCM yields racemic 5,6,7,8-tetrahydroquinoxalin-5-ol. The alcohol function in benzylic position can be protected with a bulky protecting group PG by reaction with a reagent X-PG such as tert-butyldimethylsilyl trifluoromethanesulfonate in the presence of a base like 2,6-lutidine in a solvent such as DCM. A stereoselective reduction of the pyrazine ring can be achieved by hydrogenating the protected 5,6,7,8-tetrahydroquinoxalin-5-ol with 5 bar hydrogen in the presence of a catalyst like platinum dioxide in a solvent such as a mixture of acetic acid and methanol. The product with cis,cis configuration, O-protected (4aSR,5RS,8aSR)-5-hydroxy- decahydroquinoxaline, is obtained exclusively. Various substituents R1 can be introduced regioselectively by reacting O-protected (4aSR,5RS,8aSR)-5-hydroxy-decahydroquinoxaline with reagents X-R1 in an inert solvent like DCM or THF with or without a base such as triethylamine. Subsequently the hydroxy group is deprotected. A tert-butyldimethylsilyl protecting group, for example, can be removed by reaction with a reagent such as ammonium fluoride in a solvent like methanol at elevated temperature. The α,β-aminoalcohol thus obtained is reacted with sulfuryl chloride in the presence of a base like triethylamine in an inert solvent such as DCM at reduced temperature to yield the corresponding 1,2,3- oxathiazolidine 2,2-dioxide. The residue -NR 2 R 3 can be introduced by reacting optionally substituted 1,2,3-oxathiazolidine 2,2-dioxide with an amine HNR 2 R 3 in a solvent like acetonitrile at elevated temperature followed by treatment with an acid such as aqueous hydrochloric acid. The reaction takes place under inversion of the stereogenic center. Therefore, a compound with cis,trans substitution, optionally substituted (4aRS,5SR,8aSR)-5- amino-octahydroquinoxaline, is obtained exclusively. Acylation in 4-position can be performed by reacting optionally substituted (4aRS,5SR,8aSR)-5-amino- octahydroquinoxaline with a reagent Z-A-COC1 in a solvent like DCM with or without the presence of a base such as DIEA. The target compounds can be used as such or being converted to pharmaceutically acceptable salts such as a hydrochloride by reacting the free base with the corresponding acid, e.g. hydrogen chloride in diethyl ether in a suitable solvent like DCM.
R1 can be a protecting group, e.g. a Boc, Cbz, benzyl, allyl, Alloc group, which is orthogonal to PG and can be cleaved once the residues -NR 2 R 3 and -CO-A-Z have been introduced. Subsequent reaction with reagents X-R1 as described above yields the target compounds. Reaction Scheme 2:
Synthesis of enantiomerically pure perhydroquinoxalines with cis,trans stereochemistry
Figure imgf000025_0001
Enantiomerically pure, optionally substituted (4aS,5R,8aR)-octahydroquinoxalines with cis,trans stereochemistry can be obtained as shown in Reaction Scheme 2. Racemic 5,6,7,8- tetrahydroquinoxalin-5-ol can be oxidized to the corresponding ketone with a reagent such as Dess-Martin periodinane in a suitable solvent like wet DCM. Subsequently, the ketone is subjected to a asymmetric hydrogen transfer reaction with dichloro(p-cymene)ruthenium(II) dimer, (lS,2S)-N-p-tosyl-l,2-diphenylethylenediamine and triethylammonium formate in DMF to yield enantiomerically pure (S)-5,6,7,8-tetrahydroquinoxalin-5-ol. Alternatively, the reaction can be carried out using borane DMS complex or boran THF complex in the presence of (R)-Me-CBS-oxazoborolidine in a solvent like THF. All following steps are performed as described above for the racemate. Reaction Scheme 3:
Debenzylation
Figure imgf000026_0001
Optionally substituted benzyl-protected perhydroquinoxazoline can be deprotected by hydrogenation in the presence of a catalyst such as palladium on charcoal in the presence in a suitable solvent like a mixture of THF and aqueous hydrochloric acid.
Reaction Scheme 4:
Boc-deprotection
Figure imgf000026_0002
Optionally substituted Boc-protected perhydroquinoxazoline can be deprotected with trifluoroacetic acid in DCM. Alternatively, reagents such as HCl in suitable solvents like dioxane, diethyl ether and THF may be applied.
Reaction Scheme 5:
Cbz-deprotection
Figure imgf000026_0003
Optionally substituted Cbz-protected perhydroquinoxazoline can be deprotected by hydrogenation in the presence of a catalyst such as palladium on charcoal in the presence in a suitable solvent like a THF or ethyl acetate. Alternatively, the unprotected compound can be obtained by reaction with an acid like trifluoroacetic acid in the presence of a reagent such as thioanisole.
Reaction Scheme 6:
Introduction of R1
Figure imgf000027_0001
Optionally substituted [8-aminooctahydroquinoxalin-l(2H)-yl]ethanones obtained as described in Reaction Schemes 1 to 5 can be reacted with various reagents for introduction of R1 as shown in Reaction Scheme 6.
Reaction with optionally substituted acid chlorides in an inert solvent like DCM with or without a base yields compounds wherein R1 is chosen from Q-Qo-acyl, C3-Cio-cycloacyl, phenylacyl, heteroarylacyl, C(O)COO(C1-C10-alk l) and C(O)-(CH2) COO(C1-C10-a]k l). Carbamates in which R1 is selected from COO(Ci-Cio-alkyl), COO(aryl) and COO(C3-d0- cycloalkyl) can be obtained by reacting the starting material with the corresponding optionally substituted alkyl-, aryl- and cycloalkylchloroformates in an inert solvent such as DCM.
Compounds in which R1 represents Ci-Cio-alkyl, phenylalkyl and heteroarylalkyl can be obtained using two different methodologies. The corresponding optionally substituted aldehydes can be subjected to a reductive amination reaction with optionally substituted [8- aminooctahydroquinoxalin-l(2H)-yl]ethanones to yield the alkylated compounds. The reaction is performed in a suitable solvent like MeOH in the presence of a reducing agent like NaBH3CN with pH adjustment by concentrated acetic acid. Alternatively, above mentioned residues can also be introduced in an alkylation reaction using appropriate optionally substituted Ci-Cio-alkylhalogenides, C3-Cio-cycloalkylhalogenides, phenylalkylhalogenides and heteroarylalkylhalogenides. Alkylation reactions can be conducted in a solvent like MeCN in the presence of a base such as NaHC03 or in a solvent like DCM or chloroform in the presence of a base such as DIEA.
2 3 1
If NR R contains functional groups, these can be protected before R is introduced and deprotected in a subsequent reaction step.
EXAMPLES
The following describes the preparation of the detailed examples of the invention via the above reaction schemes and their analysis.
Analytical LC-MS
Analytical conditions summary:
LC system: Agilent 1100; binary pump: Agilent G1312A; degasser; auto sampler; column heater.
Detector DAD: Agilent G1315D, 210 nm and 220-320 nm
MSD system: Agilent LC/MSD G6130B ESI (pos/neg) mass range: 100-800
Method Al:
Column Waters XBridge™ (C18, 50 x 2.1 mm, 3.5 μπι); temperature: 35°C; flow rate: 0.8 mL/min, gradient: t0 = 2% A, t3 5min = 98% A, t min = 98% A; post time: 2 minutes; eluent A: 0.1% formic acid in acetonitrile; eluent B: 0.1% formic acid in water; 220 and 220-320 nm
Method A2:
Column Waters XSelect™ (C18, 50 x 2.1 mm, 3.5 μπι); temperature: 35°C; flow rate: 0.8 mL/min, gradient: t0 = 2% A, t3 5min = 98% A, t min = 98% A; post time: 2 minutes; eluent A: 0.1% formic acid in acetonitrile; eluent B: 0.1% formic acid in water; 220 and 220-320 nm
Method A3:
Column Waters XSelect™ (C18, 150 x 4.6 mm, 3.5 μηι); temperature: 35°C; flow rate: 1 mL/min, gradient: to = 5% A, ti = 5% A tiomin = 98% A, ti5min = 98% A; post time: 5 minutes; eluent A: 0.1% formic acid in acetonitrile; eluent B: 0.1% formic acid in water; 220-320 nm Method Bl:
Column Waters XBridge™ (C18, 50 x 2.1mm, 3.5 μπι); temperature: 25°C, flow rate: 0.8 mL/min, gradient: t0 = 2% A, t3.5min = 98% A, t min = 98% A; post time: 2 min, eluent A: 95% acetonitrile + 5% 10 mM ammonium bicarbonate in water in acetonitrile, eluent B: 10 mM ammonium bicarbonate in water (pH=9.5); 220-320 nm
Method B2:
Column Waters XBridge™ (C18, 50 x 2.1mm, 3.5 μπι); temperature: 25°C, flow rate: 0.8 mL/min, gradient: to = 2% A, t3.5min = 98% A, t6min = 98% A; post time: 2 min, eluent A: 95% acetonitrile + 5% 10 mM ammonium bicarbonate in water in acetonitrile, eluent B: 10 mM ammonium bicarbonate in water (pH=9.5); 220 nm
Method B3:
Column Waters XBridge™ (C18, 50 x 2.1mm, 3.5 μπι); temperature: 25°C, flow rate: 0.8 mL/min, gradient: to = 2% A, t3.5min = 98% A, t6min = 98% A; post time: 2 min, eluent A: 95% acetonitrile + 5% 10 mM ammonium bicarbonate in water in acetonitrile, eluent B: 10 mM ammonium bicarbonate in water (pH=9.5); 210 nm
Method B4:
Column Waters XSelect™ column (C18, 50 x 2.1 mm, 3.5 μηι); temperature: 25°C, flow rate: 0.8 mL/min, gradient: t0 = 2% A, t3 5min = 98% A, t min = 98% A; post time: 2 min, eluent A: 95% acetonitrile + 5% 10 mM ammonium bicarbonate in water in acetonitrile, eluent B: 10 mM ammonium bicarbonate in water (pH=9.5); 220-320 nm Method B5:
Column Waters XSelect™ column (C18, 50 x 2.1 mm, 3.5 μηι); temperature: 25°C, flow rate: 0.8 mL/min, gradient: t0 = 2% A, t3 5min = 98% A, t min = 98% A; post time: 2 min, eluent A: 95% acetonitrile + 5% 10 mM ammonium bicarbonate in water in acetonitrile, eluent B: 10 mM ammonium bicarbonate in water (pH=9.5); 220 nm
Structures of all examples of the present invention were confirmed with 1H NMR experiments. The following describes the detailed examples of the invention which have been prepared reaction schemes 1 to 6.
Table 1:
Figure imgf000030_0001
Figure imgf000030_0002
Figure imgf000031_0001
ree ase Table 2:
Figure imgf000032_0001
Figure imgf000032_0002
Figure imgf000033_0001
Figure imgf000034_0001
Figure imgf000035_0001
Figure imgf000036_0001
Figure imgf000037_0001
Figure imgf000038_0001
The following examples are provided to illustrate the invention and are not limiting the scope of the invention in any manner.
Common Intermediates:
5,6,7,8-Tetrahydroquinoxaline 1-oxide
Figure imgf000038_0002
5,6,7,8-Tetrahydroquinoxaline (250 g) was dissolved in dichloromethane (3 1). The solution was placed under nitrogen, cooled to 3°C and 3-chloroperbenzoic acid (77%, 482 g) was added in small portions over a time period of 90 min. During addition the reaction mixture was kept below 5°C. When the addition was complete, the reaction mixture had turned into a turbid white slurry and the reaction mixture was then allowed to slowly reach ambient T overnight (18 hours reaction time). At 17°C 10% Na2S203 aq. (884 ml) was added drop wise to the stirring reaction mixture in 20 min time. A sample from the reaction mixture was checked for peroxides with a wet (water) peroxide strip. Next, sat. NaHC03 aq. (2 1) was added to the stirring reaction mixture in 30 min time and the mixture was stirred for an additional 30 min until no more gas evolved from the reaction mixture. The organic layer was divided into two portions and both portions were extracted with sat. NaHC03 aq. (500 ml). The aqueous layer from the reaction mixture was extracted three times with CH2C12 (1 1) and each CH2C12 layer was washed with sat. NaHC03 aq. (300 ml). All CH2C12 layers were combined and dried over Na2S04, filtered and evaporated in vacuo. A sample from the residue was checked for peroxides (sample in CH2C12 and wet peroxide strip). The residue was co-evaporated with Et20 and heptane. This afforded the crude product (226.8 g). The crude product was crushed with mortar and pestle and triturated in heptane (480 ml) for 2 hours. The product was filtered off, washed with heptane (200 ml) and dried in vacuo at 50°C (rotating evaporator). This afforded 187.3 g of the N-oxide. (R,S)-5,6,7,8-Tetrahydroquinoxalin-5-ol
Figure imgf000039_0001
5,6,7,8-Tetrahydroquinoxaline 1-oxide (264.4 g) was dissolved in dichloromethane (2644 ml) and the flask was placed under nitrogen, cooled to 0°C and trifluoroacetic anhydride (1109 g) was added drop wise in 100 min time, while the temperature was kept below 5°C. Next, the cooling bath under the reaction mixture was slowly allowed to reach 18°C. The reaction mixture was stirred for 17 h at 18°C (ambient T). The reaction mixture was evaporated in vacuo and stripped with CH2CI2. This afforded 633 g residue (TFA salt of the TFA ester intermediate). The residue was dissolved in dichloromethane (2644 ml) and 2 N lithium hydroxide monohydrate sol. in water (1761 ml) was added drop wise, while keeping the temperature below 20°C with an acetone dry ice bath. The reaction mixture was stirred for 1 h at ambient T. The reaction mixture was filtered over a layer of diatomaceous earth and sand. The filtrate was left at 19°C overnight. To the filtrate sat. aq. NaCl (1.5 1) was added and the layers were stirred for 10 min and was then allowed to rest for 30 min. The bottom CH2CI2 layer (-2.5 1) was isolated with a separating funnel, dried over Na2S04, filtered and evaporated in vacuo. This afforded 138.6 g of black oil which slowly solidified. The aqueous layer was extracted three times with EtOAc (1 1). The EtOAc layers were combined, dried over Na2S04, filtered and evaporated in vacuo. This afforded 45.0 g of black oil which slowly solidified. The aqueous layer was extracted four times with EtOAc (1 1). The EtOAc layers were combined, dried over Na2S04, filtered and evaporated in vacuo. This afforded 45.6 g of black oil which slowly solidified. The three batches were combined and used as such in the next step.
(R,S)-5-((tert-Butyldimethylsilyl)oxy)-5,6,7,8-tetrahydro-quinoxaline DSM
Figure imgf000040_0001
(R,S)-5,6,7,8-tetrahydroquinoxalin-5-ol (9.63 g) was dissolved in dichloromethane (300 ml) and cooled to 0°C. 2,6-Lutidine (8.96 ml) was added, followed by drop wise addition of tert- butyldimethylsilyl trifluoromethanesulfonate (17.67 ml) over a 10 minute period. Stirring was continued at 0°C for 3 hours. The reaction mixture was washed with 300 ml saturated NaHCC"3 (aq.) and the organic layer was dried over Na2S04, filtered and concentrated in vacuo (2,6-lutidine was removed by concentration with an external oil pump). The crude product was coated on Isolute (30 g) and purified by flash column chromatography with 10%- 30% EtOAc in heptane as eluent to yield the product (11.6 g) as clear brown oil. cis,cis-5-(tert-Butyldimethylsilyloxy)decahydroquinoxaline
Figure imgf000040_0002
ce mate) To a nitrogen flushed solution of (R,S)-5-(tert-butyldimethylsilyloxy)-5,6,7,8- tetrahydroquinoxaline (11.6 g) in methanol (150 ml), a slurry of platinum (IV) oxide (1.992 g) in methanol (15 ml) was added. The reaction mixture was placed under 5 bar H2 pressure (in a glass hydrogenation autoclave) and was stirred at 50°C for 68 hours. GCMS-analysis showed 39% starting material was still present and 53% desired product. To the (nitrogen flushed) reaction mixture, platinum (IV) oxide (1.494 g) was added (as a slurry in 10 ml MeOH). The reaction was continued under 5 bar H2 pressure and at 50°C for another 22 hours, after which GCMS-analysis showed 15% starting material remained. Once again platinum (IV) oxide (280 mg) was added (as a slurry in 3 ml MeOH) and the reaction was placed under 5 bar H2 pressure and stirred at 50°C for 23 hours, after which GCMS-analysis showed complete conversion. The reaction mixture was filtered over diatomaceous earth and the filtrate was evaporated in vacuo. This afforded 11.3 g product, which was used as such in the next step. cis,cis-tert-Butyl 5-(tert-butyldimethylsilyloxy)octahydroquinoxaline-l(2H)- carboxylate
Figure imgf000041_0001
To a solution of cis,cis-5-(tert-butyldimethylsilyloxy)decahydroquinoxaline (11.3 g) in dichloromethane (250 ml), di-tert-butyl dicarbonate (9.57 g) was added. The reaction mixture was stirred at RT overnight. After 18 h, the reaction mixture was diluted with 150 ml CH2CI2 and washed with 150 ml water (2 x). The CH2CI2 layer was dried over Na2S04, filtered and evaporated in vacuo. The crude material was purified by column chromatography to yield 13.9 g product. cis,cis-tert-Butyl 5-hydroxyoctahydroquinoxaline-l(2H)-carboxylate
(race mate)
Figure imgf000041_0002
To a solution of cis,cis-tert-butyl 5-(tert-butyldimethylsilyloxy)octahydroquinoxaline-l(2H)- carboxylate (13.9 g) in methanol (350 ml), ammonium fluoride (20.84 g) was added. The solution was kept under reflux conditions for 20 hours. To the reaction mixture 350 ml sat. Na2CC"3 (aq.) was added (pH>10), after which MeOH was evaporated in vacuo. The alkaline aqueous solution was extracted with EtOAc (3 x). The combined EtOAc layers were dried over Na2S04, filtered and evaporated in vacuo (1 x coevaporated with CH2CI2). This afforded 10 g crude product, which was further purified by gravity column chromatography (10% MeOH in CH2CI2). This afforded 7.47 g product that was used as such in the next step. tert-Butyl (6aSR,9aRS,9bSR)octahydro-6H-[l,2,3]oxathiazolo[3,4,5-de]quinoxaline-6- carboxylate 2,2-dioxide
Figure imgf000041_0003
At 0°C a solution of sulfuryl chloride (2.60 ml) in dichloromethane (125 ml) was added to a solution of cis,cis-tert-butyl 5-hydroxyoctahydroquinoxaline-l(2H)-carboxylate (7.47 g) and triethyl amine (11.18 ml) in dichloromethane (250 ml). The reaction mixture was slowly allowed to reach RT and stirred for 20 h. The reaction mixture was washed with 150 ml sat. NaHCC"3 (aq.) and 100 ml water. The organic layer was dried over Na2S04, filtered and evaporated in vacuo. This afforded 8.64 g crude product, which was further purified by flash column chromatography (30% EtOAc in heptane) to yield 5.53 g product, which was used as such in the next step. (4aRS,5SR,8aSR)-tert-But l-5-(pyrrolidin-l-yl)octahydroquinoxaline-l(2H)-carboxylate
Figure imgf000042_0001
A mixture of (31RS,6aRS,9aSR)-tert-butyl hexahydro-31H-[l,2,3]oxathiazolo[3,4,5-de]- quinoxaline-6(6aH)-carboxylate 2,2-dioxide (1.91 g) and pyrrolidine (1.478 ml) in anhydrous acetonitrile (50 ml) was stirred at 70°C for 22 hours. The reaction mixture was evaporated in vacuo, coevaporated with toluene and CH2C12 (removal excess pyrrolidine). The residue was taken up in CH2C12, 50 ml 10% citric acid (aq.) was added and the mixture was shaken for 2 min, after which the layers were separated. The acidic aqueous layer was basified with IN NaOH (aq.) and extracted with CH2C12 (2x 50 ml). The combined CH2C12 extracts were dried over Na2S04, filtered and evaporated in vacuo. This afforded 1.92 g product, which was used as such in the next step. cis,cis-l-Benzyl-5-(tert-butyldimethylsilyloxy)decahydroquinoxaline
Figure imgf000042_0002
(race mate)
To a solution of cis,cis-5-(tert-butyldimethylsilyloxy)decahydroquinoxaline (3.0 g) in dry N,N-dimethylformamide (105 ml), potassium carbonate (3.07 g) and benzyl bromide (1.393 ml) were added. The reaction mixture was stirred at 80°C for 1 h. The reaction mixture was evaporated in vacuo. The residue was dissolved in EtOAc, washed with water and brine and dried over Na2S04, filtered and concentrated in vacuo. The crude material was purified by flash column chromatography (5% MeOH in CH2C12) to yield 2.65 g of product. cis,cis-l-Benzyldecahydroquinoxalin-5-ol
Figure imgf000043_0001
To a solution of cis,cis-l-benzyl-5-(tert-butyldimethylsilyloxy)decahydroquinoxaline (2.65 g) in methanol (extra dry, 80 ml), ammonium fluoride (4.08 g) was added. The reaction mixture was kept under reflux conditions for 20 h. Saturated Na2C03 (aq) was added and the mixture was evaporated in vacuo (coevaporated 4 x with MeOH). The solid residue was triturated (3 x) with 100 ml CH2C12. The combined CH2C12 filtrates were dried over Na2S04, filtered and concentrated in vacuo. This afforded 1.81 g product. The product was coevaporated once with CH2C12 to remove Et20 and was used as such in the subsequent step.
(6aSR,9aRS,9bSR)-6-Benzyloctahydro-4H-[l,2,3]oxathiazolo[3,4,5-de]quinoxaline 2,2- dioxide
Figure imgf000043_0002
The reaction was performed in the dark. A solution of sulfuryl chloride (0.591 ml) in dichloromethane (20 ml) was added drop wise to a solution of cis,cis-l- benzyldecahydroquinoxalin-5-ol (1.8 g) and triethyl amine (3.05 ml) in dichloromethane (60 ml) at 0°C. The solution was stirred at 0°C for 1 h and at RT for 4 h. The mixture was partially concentrated at 35°C, filtered and immediately purified by flash chromatography (EtOAc/heptane 1/1) to afford 442 mg product which was used right away for the next step. (4aRS,5SR,8aSR)-l-Benz l-5-(pyrrolidin-l-yl)decahydroquinoxaline
Figure imgf000044_0001
Pyrrolidine (0.589 ml) was added to a solution of (31RS,6aRS,9aSR)-6-benzyloctahydro- 31H-[l,2,3]oxathiazolo[3,4,5-de]quinoxaline 2,2-dioxide (442 mg) in anhydrous acetonitrile (10 ml) and the solution was stirred at 70°C for 20 h. The mixture was concentrated in vacuo, 10 ml 1M HC1 (aq.) was added and the mixture was stirred at 50°C for 1 h. The acidic aqueous layer was washed with Et20 and basified with 2N NaOH (aq.). The basic aqueous layer was extracted with dichloromethane. The organic layer was dried over Na2S04, filtered and concentrated to afford the crude product. The residue was triturated in Et20, filtered and the filtrate was concentrated to give 360 mg product, which was used as such in the next step. cis,cis-Benzyl 5-(tert-butyldimethylsilyloxy)octahydroquinoxaline-l(2H)- carboxylate
Figure imgf000044_0002
Benzyl chloroformate (0.110 ml) was added to a solution of cis,cis-5-(tert- butyldimethylsilyloxy)decahydroquinoxaline (200 mg) in dichloromethane (4 ml) and the reaction mixture was stirred at RT for 2 h. The reaction mixture was diluted with DCM, washed with sat. Na2C03 (aq.), dried over Na2S04, filtered and concentrated. The residue was triturated in heptane, filtered and concentrated to afford 181 mg product. cis,cis-Benzyl 5-hydroxyoctahydroquinoxaline-l(2H)-carboxylate
(race mate)
Figure imgf000044_0003
Ammonium fluoride (249 mg) was added to a solution of cis,cis-benzyl 5-(tert- butyldimethylsilyloxy)octahydroquinoxaline-l(2H)-carboxylate (181 mg, 0.447 mmol) in methanol (extra dry, 5 ml) and the mixture was stirred under reflux conditions overnight. The reaction mixture was concentrated; the residue was taken in CH2CI2 and sat. Na2C03 (aq) was added. After shaking, the biphasic mixture was concentrated; the residue was taken up in CH2C12, dried over Na2S04, filtered and concentrated to afford 110 mg of product.
Benzyl (6aSR,9aRS,9bSR)octahydro-6H-[l,2,3]oxathiazolo[3,4,5-de]quinoxaline-6- carboxylate 2,2-dioxide
Figure imgf000045_0001
A solution of sulfuryl chloride (0.032 ml) in dichloromethane (1 ml) was added dropwise to a solution of cis,cis-benzyl 5-hydroxyoctahydroquinoxaline-l(2H)-carboxylate (110 mg) and triethyl amine (0.158 ml) in dichloromethane (3 ml) at 0°C. The solution was stirred at 0°C for 1 h and at RT for 1 h. The mixture was diluted with CH2C12, hydrolysed with water and the organic layer was dried over Na2S04, filtered and concentrated. Purification by flash chromatography (EtO Ac/heptane 1/1) yielded 35 mg of product. (4aRS,5SR,8aSR)-Benz l-5-(pyrrolidin-l-yl)octahydroquinoxaline-l(2H)-carboxylate
Figure imgf000045_0002
Pyrrolidine (0.024 ml) was added to a solution of (31RS,6aRS,9aSR)-benzyl hexahydro-31H- [l,2,3]oxathiazolo[3,4,5-de]quinoxaline-6(6aH)-carboxylate 2,2-dioxide (35 mg) in anhydrous acetonitrile (1 ml) and the solution was stirred at 70°C for 20 h. The mixture was concentrated in vacuo, the residue was taken up in CH2C12, washed (after thorough shaking) with 10% aqueous citric acid solution, dried over Na2S04, filtered and concentrated to yield 34 mg of product.
2- (3,4-Dichlorophenyl)acetyl chloride
Figure imgf000046_0001
To a solution of 3,4-dichlorophenylacetic acid (400 mg) in dry diethyl ether (12 ml), N,N- dimethylformamide (catalytic) and oxalyl chloride (0.184 ml) were added. The reaction mixture was stirred at RT for 2 h, concentrated, coevaporated with dichloromethane (2 x) to afford 2-(3,4-dichlorophenyl)acetyl chloride. The product was used as such in the next step.
Synthesis of Example 1:
Example 1:
(racemate)
Figure imgf000046_0002
A solution of 2-(3,4-dichlorophenyl)acetyl chloride (403 mg) in dichloromethane (2 ml) was added to a solution of (4aRS,5SR,8aSR)-l-benzyl-5-(pyrrolidin-l-yl)decahydroquinoxaline (360 mg) in dichloromethane (6 ml) at RT and the reaction mixture was stirred at RT overnight. The reaction mixture was diluted with dichloromethane and hydrolysed with water. The aqueous layer was basified with 0.5M NaOH (aq.). The organic layer was dried over Na2SC"4, filtered and concentrated in vacuo. Purification by flash chromatography (eluent CH2Cl2/3-10% MeOH) yielded 460 mg product.
Synthesis of Example 2:
Example 2: (racemate)
Figure imgf000047_0001
A solution of 2-(3,4-dichlorophenyl)acetyl chloride (31.2 mg) in dichloromethane (1 ml) was added to a solution of (4aRS,5SR,8aSR)-benzyl-5-(pyrrolidin-l-yl)octahydroquinoxaline- l(2H)-carboxylate (32 mg) and N,N-diisopropylethylamine (0.032 ml) in dichloromethane (2 ml) at RT. The reaction mixture was stirred at RT overnight. The reaction mixture was diluted with CH2CI2 and hydrolysed with water. The aqueous layer was basified with 0.5 M NaOH (aq.), the organic layer was dried over Na2S04, filtered and concentrated in vacuo. Purification by flash column chromatography (eluent CH2Cl2/5-10% MeOH) followed by trituration in Et20 provided the final product.
Synthesis of Example 3:
Example 3:
Figure imgf000047_0002
(racemate) To a solution of (4aRS,5SR,8aSR)-tert-butyl-5-(pyrrolidin-l-yl)octahydroquinoxaline-l(2H)- carboxylate (1.92 g) and N,N-diisopropylethylamine (2.124 ml) in dichloromethane (160 ml), a solution of 2-(3,4-dichlorophenyl)acetyl chloride (2.080 g) in dichloromethane (80 ml) was added in 30-45 min time. The reaction mixture was stirred at RT for 1 h. The reaction mixture was washed with 2 x 50 ml 0.5N NaOH (aq.). The organic layer was dried over Na2S04, filtered and evaporated in vacuo. The crude product was purified by flash chromatography (1% MeOH (7N NH3) in CH2C12).
Synthesis of Example 9:
Intermediate 9a) (preparation 1):
Figure imgf000048_0001
(racemate)
To a solution of Example 3 (527 mg) in dichloromethane (5 ml), trifluoroacetic acid (2.358 ml) was added. The reaction mixture was stirred at RT overnight. The reaction mixture was evaporated in vacuo and coevaporated with toluene and with CH2C12 (2 x). The residue was dissolved in CH2C12 and washed with 0.5N NaOH (aq.) and water. The CH2C12 layer was dried over Na2S04, filtered and evaporated in vacuo.
Intermediate 9a) (preparation 2):
Figure imgf000048_0002
(racemate)
Concentrated HC1 (36% in H20, 8 ml) and palladium, 10% on activated carbon (150 mg) were added to a degassed solution of Example 2 (380 mg) in tetrahydrofuran (40 ml) and water (40 ml). The mixture was stirred under H2 atmosphere (balloon, 1 bar) at RT for 4 h. Extra palladium, 10% on activated carbon (150 mg) was added and the stirring was continued under 1 bar H2 atmosphere for 1 h. The mixture was filtered and partially concentrated to remove THF. The acidic water layer was washed with Et20, basified with 1M NaOH (aq.) and extracted with CH2C12. The organic layer was dried over Na2S04, filtered and concentrated. The crude product was purified by flash chromatography.
Example 9:
Figure imgf000049_0001
Intermediate 9a) (50 mg) was dissolved in dichloromethane (2 ml). Methyl 4-(chloro- carbonyl)benzoate (30.1 mg) and N,N-diisopropylethylamine (24.92 mg) were added and the reaction mixture was stirred at ambient temperature overnight. The reaction mixture was diluted with dichloromethane (10 ml) and washed with 10 ml sat. NaHC03 (aq.) and brine (10 ml). The organic phase was dried over Na2S04, filtered and concentrated in vacuo to yield 74 mg of crude product. Purification by flash column chromatography with 0-7% MeOH in CH2C12 as eluent yielded 45.7 mg desired product. The product was converted to the corresponding HC1 salt. The free base was dissolved in CH2C12 (2 ml), 1M HC1 in Et20 (1 ml) was added and the mixture was stirred at RT for 1 h. The mixture was concentrated in vacuo and coevaporated with Et20 (3 x 2 ml). The product was dried under reduced pressure. Synthesis of Example 12:
Example 12:
Figure imgf000050_0001
Example 9 (31 mg) was dissolved in CH2CI2 (3 ml) and washed with IN NaOH (aq., 2 ml). The organic layer was separated and concentrated in vacuo to yield the free amine. Enantiomers were separated using chiral preparative HPLC (OD column, flow rate: 18 mL/min, eluent heptane/EtOH 8:2 + 0.1% diethylamine). After concentration of the product fractions in vacuo, both enantiomers were lyophilized from acetonitrile/water (1:1) to give 9 mg of Example 12 (first peak) and 9 mg of its enantiomer (second peak). The ee for both enantiomers was >98%.
BIOLOGICAL ASSAYS
A. μ Opioid receptor binding assay (CHO-Kl cell membrane preparations)
Human opiate μ receptors expressed in CHO-Kl cells are used in modified Tris-HCl buffer pH 7.4. An 11 μg aliquot is incubated with 0.6 nM [ HJDiprenorphine for 60 minutes at 25°C. Nonspecific binding is estimated in the presence of 10 μΜ naloxone. Membranes are filtered and washed, the filters are then counted to determine [ HJDiprenorphine specifically bound. Test compounds are screened at various concentrations (see e.g. Wang, J.B. FEBS Lett. 1994;338:217-222).
B. μ Opioid receptor functional assay (GTPyS Binding) Human recombinant opiate μ receptors stably expressed in CHO-Kl cells are used. Test compound and/or vehicle is preincubated with the membranes (0.016 mg/ml) and 3 mM GDP in modified HEPES pH 7.4 buffer for 20 minutes at 25°C and SPA beads are then added for another 60 minutes at 30°C. The reaction is initiated by 0.3 nM [ 35 S]GTP S for an additional 30 minute incubation period. Test compound-induced inhibition of 0.1 μΜ DAMGO-induced increase of [ 35 S]GTP S binding response by 50 percent or more (>50%) indicates receptor antagonist activity. Compounds are screened at various concentrations.
Table 3: μ Opioid receptor binding (determination as described in biological assays A)
Figure imgf000051_0001
24 85
25 72
26 73
27 81
28 89
29 94
30 80
31 95
32 65
33 88
34 92
35 76
36 81
37 92
38 87
39 58
40 76
41 95
42 82
43 87
44 76
45 101
46 59
47 94
48 84
49 95
Table 4: μ Opioid functional activity (determination as described in biological assays B) IC50 values are grouped in three classes: a < 10 nM; b > 10 nM and < 100 nM; c >100 nM and < 1 μΜ
Example GTPyS % inhibition functional (nM) assay at 1 μΜ c 71 a 101 b 98 c 70 a 102 b 99 b 99 c 77 c 80 c 66 c 89 b 99 b 95 a 99 b 93 c 77 b 98 b 92 b 95 b 97 b 99 a 100 b 96 a 100 b 93 b 92 c 80 c 58 c 61 c 62 38 c 73
39 c 67
40 c 82
41 b 98
42 c 77
43 c 90
44 c 74
45 a 101
46 c 64
47 b 98
48 b 90
49 b 98
Table 5: μ Opioid functional activity for reference compounds from WO2009/080745 (determination as described in biological assays B)
Figure imgf000054_0001
Figure imgf000054_0002
Figure imgf000055_0001
Figure imgf000056_0001
Figure imgf000057_0001
The data in Table 5 show that all reference compounds of WO2009/080745 are no functional antagonists of the μ opioid receptor. Thus, the compounds of formula (1) according to the present invention (having the 4aS,5R,8aR stereochemistry) provide for improved and unexpected technical effects.
C. In vivo model for pruritus associated with the oxazolone model of a delayed type hypersensitivity reaction Scratching activity in mice is measured after topical application of the test compound. Ear thickness is measured and histology parameters are determined (see e.g. Elliott G.R. An automated method for registering and quantifying scratching activity in mice: use for drug evaluation. J. Pharmacol. Toxicol. Methods. 2000;44:453-459 and Gijbels M.J. Therapeutic interventions in mice with chronic proliferative dermatitis (cpdm/cpdm). Exp. Dermatol. 2000;9:351-358).
D. In vivo model of chronic oxazolone-induced ear inflammation
Mice are challenged several times with oxazolone following an initial sensitization. Ear thickness is measured daily during the treatment period with topical application of the test compound (see e.g. Ottosen E.R. J. Med. Chem. 2003;46: 5651-5662). At the end of the study ear weight is determined. Ears are characterized histologically and by immunofluorescence. Gene expression was quantified (RT-qPCR). E. Mouse model of topical arachidonic acid-induced ear inflammation Arachidonic acid in acetone is applied topically to the anterior and posterior surfaces of the right ear of mice. Test substances are similarly applied 30 minutes before and 15 minutes after arachidonic acid. Ear swelling is measured 1 h after application of arachidonic acid. Scratching activity is monitored for 1 h following the application of arachidonic acid. Ear weight and histology parameters are determined at the end of the study (see e.g. Chang J. Eur. J. Pharmacol. 1987;142: 197-205).
Treatment with examples 9 and 12, respectively, (topical) dose dependently prevented the increase in ear thickness observed for the vehicle control. F. Effects on chloroquine-induced scratching
Compounds are intrathecally injected in a volume of 5 μΐ, 10 min before the i.d. injection of chloroquine (100 μg/ 10 μΐ) in the rostral back. Following the i.d. cheek injection, mice are placed in an arena with a clear glass floor and videotaped from beneath for 30 min. Videotapes are reviewed by blinded investigators, who count the number of hindlimb scratch bouts.
Treatment with example 9 significantly inhibited chloroquine-evoked scratching. G. Pharmacokinetic studies, evaluation of clinical signs
The test items are administered intravenously to Wistar rats. Blood samples are taken after 15 minutes and after 1 h following administration. Perfused brains are collected 1 h following administration of the test item. Brain and plasma concentrations are measured. Clinical signs are monitored 15 minutes and 1 h after dosing.
Examples of a Pharmaceutical Composition
Composition Example 10:
Cream
Compound 10 1.00
Cetostearyl alcohol 7.00
Macrogol-6-cetostearyl ether 1.50
Macrogol-25-cetostearyl ether 1.50 Liquid paraffin 12.00
Propylene glycol 8.00
Methylparaben 0.15
Ethylparaben 0.08
Butylhydroxytoluene 0.04
Disodium edetate 0.05
Water 68.68
Composition Example 12:
Gel
Compound 12 0.50
Ethanol 15.00
Polyoxyl 40 Hydrogenated Castor Oil 1.00
Butylhydroxytoluene 0.04
Disodium edetate 0.05
Carbomer 0.50
Triethanolamine 0.70
Water 82.21 Composition Example 10:
As a specific embodiment of an oral composition of a compound of the present invention, 21 mg of Example 10 is formulated with sufficient finely divided lactose to provide a total amount of 580 to 590 mg to fill a size 0 hard gelatine capsule.
Composition Example 12:
As another specific embodiment of an oral composition of a compound of the present invention, 20 mg of Example 12 is formulated with sufficient finely divided lactose to provide a total amount of 580 to 590 mg to fill a size 0 hard gelatine capsule.

Claims

Claims
1. A perhydroquinoxaline compound according to the general formula (1) as shown below or a solvate or hydrate thereof or a pharmaceutically acceptable salt thereof:
Figure imgf000060_0001
wherein:
R1 is chosen from the group comprising H; Ci-Cio-alkyl; C3-Cio-cycloalkyl;
(COO(Ci-Cio-alkyl);
phenylalkyl with Ci-C6-alkyl, wherein the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising halogen, Ci-C6- alkyloxy, NH2, NH(Ci-C5-alkyl), N(Ci-C5-alkyl)2, OH, S02(Ci-C5-alkyl), SO(Ci-C5-alkyl), CF3, CN, N02, S02N(Ci-C5-alkyl)2, S02NH2, S02NH(Ci-C5-alkyl), S02NH(aryl), S02NH(phenyl) and/or S02NH(heteroaryl);
Ci-Cio-acyl; heterocyclylacyl containing one, two, three or four hetero atoms chosen from the group comprising NH, O and/or S; phenylacyl, wherein the acyl radical is a Ci-C6-acyl radical and the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising halogen, Ci-C6-alkyloxy, COO(Ci-C6- alkyl), NH2, NH(Ci-C5-alkyl), N(Ci-C5-alkyl)2, CONH2, CONH(Ci-C6-alkyl), CON(Ci-C6- alkyl)2, OH, S02(CrC5-alkyl), SO(C C5-alkyl), CF3, CN, N02, S02N(CrC5-alkyl)2, S02NH2, S02NH(C C5-alkyl), S02NH(aryl), S02NH(phenyl) and/or S02NH(heteroaryl);
mono-, bi- or tricyclic heteroaryl containing one, two, three or four hetero atoms chosen from the group comprising N, O and/or S; mono-, bi- or tricyclic heteroarylalkyl containing one, two, three or four hetero atoms chosen from the group comprising N, O and/or S, wherein the alkyl radical is a Ci-C6 alkyl radical;
mono-, bi- or tricyclic heteroarylacyl containing one, two, three or four hetero atoms chosen from the group comprising N, O and/or S, wherein the acyl radical is a Ci-C6- acyl radical and the heteroaryl radical can be substituted by one or more identical or different groups chosen from the group comprising halogen, Ci-C6-alkyloxy, COO(Ci-C6-alkyl), NH2, NH(C C5-alkyl), N(C C5-alkyl)2, CONH2, CONH(C C6-alkyl), CON(C C6-alkyl)2, OH, CF3, CN, N02, and/or S02NH2;
mono-, bi- or tricyclic (heteroaryl) alkenylacyl containing one, two, three or four hetero atoms chosen from the group comprising N, O and/or S, wherein the acyl radical is a Ci-C6-acyl radical and the alkenyl radical is a C2-C6-alkenyl radical;
C(0)NH(C Cio-alkyl); C(O)N(C1-C10-alk l)2, wherein the two alkyl radicals may form a saturated substituted or unsubstituted ring with the N atom; C(0)NH(aryl); C(0)NH(benzyl); C(O)(C3-Ci0-cycloalkyl); COO(aryl); COO(benzyl); COO(C3-Ci0- cycloalkyl);
(CH2)g-COOH, wherein g is 1, 2, 3 or 4; (CH2)h-COO(C C6-alkyl), wherein h is 1, 2, 3 or 4; (CH2)i-CONH2, wherein i is 1, 2, 3 or 4;
C(0)NH-(CH2)j-COOH, wherein j is 0, 1, 2, 3 or 4; C(0)NH-(CH2)k-COO(Ci- C6-alkyl), wherein k is 0, 1, 2, 3 or 4; C(0)NH-(CH2)i-CONH2, wherein 1 is 0, 1, 2, 3 or 4;
COO-(CH2)m-COOH, wherein m is 0, 1, 2, 3 or 4; COO-(CH2)n-COO(C C10- alkyl), wherein n is 0, 1, 2, 3 or 4; COO-(CH2)p-C(0)NH2, wherein p is 0, 1, 2, 3 or 4; C(O)- (CH2)q-COOH, wherein q is 0, 1, 2, 3 or 4; C(O)-(CH2)r-COO(Ci-Ci0-alkyl), wherein r is 0, 1, 2, 3 or 4; C(0)-(CH2)s-C(0)NH2, wherein s is 0, 1, 2, 3 or 4; C(0)-(CH2)t-C(0)NH(C1-C6- alkyl), wherein t is 0, 1, 2, 3 or 4; C(0)-(CH2)u-C(0)N(Ci-C6-alkyl)2, wherein u is 0, 1, 2, 3 or 4;
C(0)-(CH2)v-NH2, wherein v is 0, 1, 2, 3 or 4; C(0)-(CH2)w-OR', wherein w is 0, 1, 2, 3 or 4 and R' is H or C C6-acyl; C(0)-(CH2)x-C(0)NH-(CH2)yC(0)NH2, wherein x is 0, 1, 2 or 3 and wherein y is 0, 1, 2 or 3;
S02(Ci-C6-alkyl); S02-(CH2)z-heteroaryl, wherein z is 0, 1, 2 or 3; S02(CH2)a- heterocyclyl, wherein a is 0, 1, 2 or 3 and wherein the heterocyclyl residue may be substituted by one or more identical or different substituents chosen from the group comprising halogen, OH, CN, oxo and/or C C6-alkoxy; S02N(C C6-alkyl)2 or S02NH(C C6-alkyl), wherein the alkyl radical can be substituted by halogen, Ci-C4-alkoxy and/or OH; S02NH(C3-C6- cycloalkyl); S02NH-C(0)0(Ci-C6-alkyl);
R 2 , R 3
are in each case identical or independent of each other and are chosen from the group comprising H; Ci-Cio-alkyl; C3-Cio-cycloalkyl,
or
R 2 3
and R form, together with the nitrogen to which they are bonded, a saturated or unsaturated 3- to 8-membered N-heterocycle, wherein this can be substituted by one or more identical or different groups chosen from the group comprising halogen, OH, Ci- C4-alkyloxy, COOH, COO(Ci-Cio-alkyl), CONH2, CONH(Ci-Cio-alkyl), CON(Ci-Ci0- alkyl)2, CN, and/or 0-C(0)(C C6 alkyl);
A is chosen from the group comprising (CH2)b, wherein b is 0, 1, 2, 3, 4, 5, or 6;
C2-C5 alkylene, which can be substituted by at least one C1-C3 alkyl radical; O; S; NH and/or aryl;
Z is chosen from the group comprising H; NH2; COOH; COO(Ci-C5-alkyl);
CH(NH2)COOH; C C6-acyl;
phenyl, which can be substituted by one or more identical or different groups chosen from the group comprising halogen, Ci-C5-alkyl, Ci-C5-alkoxy, NH2, NH(Ci-C5-alkyl), N(Ci-C5- alkyl)2, OH, S02(CrC5-alkyl), SO(C C5-alkyl), CF3, CN, N02, S02N(CrC5-alkyl)2, S02NH2, S02NH(C C5-alkyl), S02NH(aryl), S02NH(phenyl) and/or S02NH(heteroaryl), wherein the substituents may form a ring;
a mono- or bicyclic aryl or heteroaryl containing one or two hetero atoms chosen from the group comprising N, O and/or S, wherein the aryl or heteroaryl group can be substituted by one or more identical or different groups chosen from the group comprising halogen, C C4-alkoxy, NH2, NH(C C5-alkyl), N(C C5-alkyl)2, OH, S02(C C5-alkyl), SO(C C5-alkyl), CF3, CN, N02, S02N(CrC5-alkyl)2, S02NH2, S02NH(CrC5-alkyl), S02NH(aryl), S02NH(phenyl) and/or S02NH(heteroaryl).
2. The compound according to claim 1, wherein in general formula (1): R1 is chosen from the group comprising H; Ci-C3-alkyl; COO(Ci-C4-alkyl);
benzyl;
Ci-C4-acyl; C(0)(C4-C6-cycloalkyl); heterocyclylacyl containing NH or O in the ring; phenylacyl, wherein the acyl radical is a Ci-acyl radical and the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(Ci-C3-alkyl) and CONH2;
mono-cyclic heteroaryl containing one hetero atom chosen from the group of
N, O and S;
mono-cyclic heteroarylalkyl containing one or two hetero atom chosen from the group of N, O and S, wherein the alkyl radical is a C1-C3 alkyl radical;
mono-cyclic heteroarylacyl containing one or two hetero atoms chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the heteroaryl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(C C3-alkyl) and CONH2;
mono-cyclic (heteroaryl) alkenylacyl containing one hetero atom chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the alkenyl radical is a C2-C4- alkenyl radical;
C(0)NH(C C3-alkyl); C(0)N(C C3-alkyl)2, wherein the two alkyl radicals may form a saturated halogen substituted or unsubstituted ring with the N atom; C(0)NH(phenyl); C(0)NH(benzyl); C(0)(C3-C6-cycloalkyl); COO(benzyl);
(CH2)g-COOH, wherein g is 1, 2, 3 or 4; (CH2)h-COO(C C6-alkyl), wherein h is 1, 2, 3 or 4; (CH2)i-CONH2, wherein i is 1, 2, 3 or 4;
C(0)NH-(CH2)j-COOH, wherein j is 0 or 1; C(0)NH-(CH2)k-COO(Ci-C3- alkyl), wherein k is 0 or 1; C(0)NH-(CH2)i-CONH2, wherein 1 is 0 or 1;
COO-(CH2)m-COOH, wherein m is 0 or 1; COO-(CH2)n-COO(Ci-C3-alkyl), wherein n is 0 or 1; COO-(CH2)p-C(0)NH2, wherein p is 0 or 1; C(0)-(CH2)q-COOH, wherein q is 0 or 1; C(0)-(CH2)r-COO(C C3-alkyl), wherein r is 0 or 1; C(0)-(CH2)s- C(0)NH2, wherein s is 0 or 1; C(0)-(CH2)t-C(0)NH(C C3-alkyl), wherein t is 0 or 1; C(O)- (CH2)u-C(0)N(C C3-alkyl)2, wherein u is 0 or 1;
C(0)-(CH2)v-NH2, wherein v is 0 or 1 ; C(0)-(CH2)w-OR' , wherein w is 0 or 1 and R' is H or Ci-acyl; C(0)-(CH2)x-C(0)NH-(CH2)yC(0)NH2, wherein x is 0 or 1 and wherein y is 0 or 1 ; S02(Ci-C6-alkyl); S02-(CH2)z-heteroaryl, wherein z is 0 or 1; S02(CH2)a- heterocyclyl, wherein a is 0 or 1, wherein the heteroatoms are O, N, and/or S and wherein the heterocyclyl residue may be substituted by one or more identical or different substituents chosen from the group comprising F, CI, OH, CN, oxo and/or Ci-C3-alkoxy; S02N(Ci-C3- alkyl)2 or S02NH(Ci-C3-alkyl), wherein the alkyl radical can be substituted by F, CI, C1-C3- alkoxy and/or OH; S02NH(C3-C6-cycloalkyl); S02NH-C(0)0(Ci-C3- alkyl);
R 2 , R 3 are identical or different and are chosen from the group comprising H, methyl, ethyl, n-propyl, and i-propyl,
or
R 2 and R 3 form, together with the nitrogen to which they are bonded, a saturated or mono-unsaturated 4- to 6-membered N-heterocycle, wherein this can be substituted by one or more identical or different groups chosen from the group comprising F, CI, OH, CONH2, CN, and/or 0-C(0)(C C3 alkyl);
A is (CH2)b, wherein b is 1;
Z is chosen from the group comprising
phenyl, which can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C3-alkyl, Ci-C3-alkoxy, OH, CF3, and N02, wherein two OH substituents may be connected by an ether bridge to form a ring or wherein two C1-C3- alkyl groups may be connected to form a saturated ring; and
a mono- or bicyclic aryl or heteroaryl containing one hetero atom chosen from the group of N and S, wherein the aryl or heteroaryl group can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C3-alkyl, C1-C3- alkoxy, OH, CF3, and N02.
3. The compound according to claim 1 and/or claim 2, wherein in general formula (1): is chosen from the group consisting of Ci-acyl (formyl); heterocyclylacyl containing NH or O in the ring; phenylacyl, wherein the acyl radical is a Ci-acyl radical and the phenyl radical is substituted by one or more of COO(CrC3-alkyl) and CONH2;
mono-cyclic heteroarylacyl containing one or two hetero atoms chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the heteroaryl radical is substituted by one or more of COO(Ci-C3-alkyl) and CONH2;
mono-cyclic (heteroaryl) alkenylacyl containing one hetero atom chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the alkenyl radical is a C2-C4- alkenyl radical;
C(0)NH(Ci-C3-alkyl); C(0)N(Ci-C3-alkyl)2, wherein the two alkyl radicals form a saturated halogen substituted or unsubstituted ring with the N atom; C(0)NH (phenyl); C(0)NH(benzyl); COO(benzyl);
(CH2)g-COOH, wherein g is 1, 2, 3 or 4; (CH2)h-COO(C C6-alkyl), wherein h is 1, 2, 3 or 4; (CH2)i-CONH2, wherein i is 1, 2, 3 or 4;
C(0)NH-(CH2)j-COOH, wherein j is 0 or 1; C(0)NH-(CH2)k-COO(Ci-C3- alkyl), wherein k is 0 or 1; C(0)NH-(CH2)i-CONH2, wherein 1 is 0 or 1;
COO-(CH2)m-COOH, wherein m is 0 or 1; COO-(CH2)n-COO(C C3-alkyl), wherein n is 0 or 1; COO-(CH2)p-C(0)NH2, wherein p is 0 or 1; C(0)-(CH2)s-C(0)NH2, wherein s is 0 or 1; C(0)-(CH2)t-C(0)NH(Ci-C3-alkyl), wherein t is 0 or 1; C(0)-(CH2)u- C(0)N(Ci-C3-alkyl)2, wherein u is 0 or 1 ;
C(0)-(CH2)v-NH2, wherein v is 1 ; C(0)-(CH2)w-OR', wherein w is 1 and R' is
Figure imgf000065_0001
S02(Ci-C6-alkyl); S02-(CH2)z-heteroaryl, wherein z is 0 or 1; S02(CH2)a- heterocyclyl, wherein a is 0 or 1, wherein the heteroatoms are O, N, and/or S and wherein the heterocyclyl residue may be substituted by one or more identical or different substituents chosen from the group comprising F, CI, OH, CN, oxo and/or Ci-C3-alkoxy; S02N(Ci-C3- alkyl)2 or S02NH(Ci-C3-alkyl), wherein the alkyl radical can be substituted by F, CI, Ci-C3- alkoxy and/or OH; S02NH(C3-C6-cycloalkyl); S02NH-C(0)0(C C3- alkyl);
R 2 , R 3 are identical or different and are chosen from the group comprising H, methyl, ethyl, n-propyl, and i-propyl,
or R 2 and R 3 form, together with the nitrogen to which they are bonded, a saturated or mono-unsaturated 4- to 6-membered N-heterocycle, wherein this can be substituted by one or more identical or different groups chosen from the group comprising F, CI, OH, CONH2, CN, and/or 0-C(0)(C C3 alkyl);
A is (CH2)b, wherein b is 1;
Z is chosen from the group comprising
phenyl, which can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C3-alkyl, Ci-C3-alkoxy, OH, CF3, and N02, wherein two OH substituents may be connected by an ether bridge to form a ring or wherein two Ci-C3- alkyl groups may be connected to form a saturated ring; and
a mono- or bicyclic aryl or heteroaryl containing one hetero atom chosen from the group of N and S, wherein the aryl or heteroaryl group can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C3-alkyl, Ci-C3- alkoxy, OH, CF3, and N02.
4. The compound according to claim 1 and/or claim 2, wherein in general formula (1):
R1 is chosen from the group comprising H; Ci-C3-alkyl; COO(Ci-C4-alkyl);
benzyl;
Ci-C4-acyl; C(0)(C4-C6-cycloalkyl); heterocyclylacyl containing NH or O in the ring; phenylacyl, wherein the acyl radical is a Ci-acyl radical and the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(C C3-alkyl) and CONH2;
mono-cyclic heteroaryl containing one hetero atom chosen from the group of
N, O and S;
mono-cyclic heteroarylalkyl containing one or two hetero atom chosen from the group of N, O and S, wherein the alkyl radical is a Ci-C3 alkyl radical;
mono-cyclic heteroarylacyl containing one or two hetero atoms chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the heteroaryl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(Ci-C3-alkyl) and CONH2;
mono-cyclic (heteroaryl)alkenylacyl containing one hetero atom chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the alkenyl radical is a C2-C4- alkenyl radical;
C(0)NH(Ci-C3-alkyl); C(0)N(Ci-C3-alkyl)2, wherein the two alkyl radicals may form a saturated halogen substituted or unsubstituted ring with the N atom; C(0)NH(phenyl); C(0)NH(benzyl); C(0)(C3-C6-cycloalkyl); COO(benzyl);
(CH2)g-COOH, wherein g is 1, 2, 3 or 4; (CH2)h-COO(Ci-C6-alkyl), wherein h is 1, 2, 3 or 4; (CH2)i-CONH2, wherein i is 1, 2, 3 or 4;
C(0)NH-(CH2)j-COOH, wherein j is 0 or 1; C(0)NH-(CH2)k-COO(C C3- alkyl), wherein k is 0 or 1; C(0)NH-(CH2)rCONH2, wherein 1 is 0 or 1;
COO-(CH2)m-COOH, wherein m is 0 or 1; COO-(CH2)n-COO(C C3-alkyl), wherein n is 0 or 1; COO-(CH2)p-C(0)NH2, wherein p is 0 or 1; C(0)-(CH2)q-COOH, wherein q is 0 or 1; C(0)-(CH2)r-COO(Ci-C3-alkyl), wherein r is 0 or 1; C(0)-(CH2)s- C(0)NH2, wherein s is 0 or 1; C(0)-(CH2)t-C(0)NH(Ci-C3-alkyl), wherein t is 0 or 1; C(O)- (CH2)u-C(0)N(C C3-alkyl)2, wherein u is 0 or 1;
C(0)-(CH2)v-NH2, wherein v is 0 or 1 ; C(0)-(CH2)w-OR', wherein w is 0 or 1 and R' is H or Ci-acyl; C(0)-(CH2)x-C(0)NH-(CH2)yC(0)NH2, wherein x is 0 or 1 and wherein y is 0 or 1 ;
S02(C C6-alkyl); S02-(CH2)z-heteroaryl, wherein z is 0 or 1; S02(CH2)a- heterocyclyl, wherein a is 0 or 1, wherein the heteroatoms are O, N, and/or S and wherein the heterocyclyl residue may be substituted by one or more identical or different substituents chosen from the group comprising F, CI, OH, CN, oxo and/or Ci-C3-alkoxy; S02N(Ci-C3- alkyl)2 or S02NH(Ci-C3-alkyl), wherein the alkyl radical can be substituted by F, CI, Ci-C3- alkoxy and/or OH; S02NH(C3-C6-cycloalkyl); S02NH-C(0)0(C C3- alkyl);
R 2 and R 3 form, together with the nitrogen to which they are bonded, a mono- unsaturated 6-membered N-heterocycle, that may be substituted by one or more of F, CI, OH, CONH2, CN, and/or 0-C(0)(Ci-C3 alkyl);
A is (CH2)b, wherein b is 1; Z is chosen from the group comprising
phenyl, which can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C3-alkyl, Ci-C3-alkoxy, OH, CF3, and N02, wherein two OH substituents may be connected by an ether bridge to form a ring or wherein two Ci-C3-alkyl groups may be connected to form a saturated ring; and
a mono- or bicyclic aryl or heteroaryl containing one hetero atom chosen from the group of N and S, wherein the aryl or heteroaryl group can be substituted by one or more identical or different groups chosen from the group comprising F, CI, Ci-C3-alkyl, Ci-C3- alkoxy, OH, CF3, and N02.
5. The compound according to claim 1 and/or claim 2, wherein in general formula (1): R1 is chosen from the group comprising H; Ci-C3-alkyl; COO(Ci-C4-alkyl);
benzyl;
Ci-C4-acyl; C(0)(C4-C6-cycloalkyl); heterocyclylacyl containing NH or O in the ring; phenylacyl, wherein the acyl radical is a Ci-acyl radical and the phenyl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(Ci-C3-alkyl) and CONH2;
mono-cyclic heteroaryl containing one hetero atom chosen from the group of
N, O and S;
mono-cyclic heteroarylalkyl containing one or two hetero atom chosen from the group of N, O and S, wherein the alkyl radical is a Ci-C3 alkyl radical;
mono-cyclic heteroarylacyl containing one or two hetero atoms chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the heteroaryl radical can be substituted by one or more identical or different groups chosen from the group comprising COO(C C3-alkyl) and CONH2;
mono-cyclic (heteroaryl) alkenylacyl containing one hetero atom chosen from the group of N, O and S, wherein the acyl radical is a Ci-acyl radical and the alkenyl radical is a C2-C4- alkenyl radical; C(0)NH(Ci-C3-alkyl); C(0)N(Ci-C3-alkyl)2, wherein the two alkyl radicals may form a saturated halogen substituted or unsubstituted ring with the N atom; C(0)NH(phenyl); C(0)NH(benzyl); C(0)(C3-C6-cycloalkyl); COO(benzyl);
(CH2)g-COOH, wherein g is 1, 2, 3 or 4; (CH2)h-COO(C C6-alkyl), wherein h is 1, 2, 3 or 4; (CH2)i-CONH2, wherein i is 1, 2, 3 or 4;
C(0)NH-(CH2)j-COOH, wherein j is 0 or 1; C(0)NH-(CH2)k-COO(Ci-C3- alkyl), wherein k is 0 or 1; C(0)NH-(CH2)rCONH2, wherein 1 is 0 or 1;
COO-(CH2)m-COOH, wherein m is 0 or 1; COO-(CH2)n-COO(C C3-alkyl), wherein n is 0 or 1; COO-(CH2)p-C(0)NH2, wherein p is 0 or 1; C(0)-(CH2)q-COOH, wherein q is 0 or 1; C(0)-(CH2)r-COO(Ci-C3-alkyl), wherein r is 0 or 1; C(0)-(CH2)s- C(0)NH2, wherein s is 0 or 1; C(0)-(CH2)t-C(0)NH(C C3-alkyl), wherein t is 0 or 1; C(O)- (CH2)u-C(0)N(C C3-alkyl)2, wherein u is 0 or 1;
C(0)-(CH2)v-NH2, wherein v is 0 or 1 ; C(0)-(CH2)w-OR', wherein w is 0 or 1 and R' is H or C acyl; C(0)-(CH2)x-C(0)NH-(CH2)yC(0)NH2, wherein x is 0 or 1 and wherein y is 0 or 1 ;
S02(Ci-C6-alkyl); S02-(CH2)z-heteroaryl, wherein z is 0 or 1; S02(CH2)a- heterocyclyl, wherein a is 0 or 1, wherein the heteroatoms are O, N, and/or S and wherein the heterocyclyl residue may be substituted by one or more identical or different substituents chosen from the group comprising F, CI, OH, CN, oxo and/or Ci-C3-alkoxy; S02N(Ci-C3- alkyl)2 or S02NH(Ci-C3-alkyl), wherein the alkyl radical can be substituted by F, CI, Ci-C3- alkoxy and/or OH; S02NH(C3-C6-cycloalkyl); S02NH-C(0)0(C C3- alkyl);
R 2 , R 3 are identical or different and are chosen from the group comprising H, methyl, ethyl, n-propyl, and i-propyl,
or
R 2 and R 3 form, together with the nitrogen to which they are bonded, a saturated or mono-unsaturated 4- to 6-membered N-heterocycle, wherein this can be substituted by one or more identical or different groups chosen from the group comprising F, CI, OH, CONH2, CN, and/or 0-C(0)(C C3 alkyl);
A is (CH2)b, wherein b is 1; Z is either a tetrahydronaphthyl or a 2,3-dihydrobenzo-l,4-dioxinyl residue, optionally substituted by one or more of F, CI, Ci-C3-alkyl, Ci-C3-alkoxy, OH, CF3, and N02.
6. The compound as claimed in one of the preceding claims for use as a medicament.
7. The compound for use as a medicament as claimed in claim 6 for the therapeutic and/or prophylactic treatment of opioid induced side effects and diseases having the same or similar symptoms.
8. The compound for use as a medicament as claimed in claim 6 and/or claim 7, characterized in that the disease is selected from gastrointestinal dysfunction, inhibition of intestinal motility, constipation, GI sphincter constriction, nausea, emesis, biliary spasm, opioid bowel dysfunction, colic, dysphoria, pruritus, urinary retention, depression of respiration, papillary constriction, cardiovascular effects, chest wall rigidity and cough suppression, depression of stress response, and immune suppression associated with use of narcotic analgesia, or combinations thereof.
9. The compound for use as a medicament as claimed in any one of claims 6 to 8, characterized in that the disease is selected from irritable bowel syndrome, opioid-induced bowel dysfunction, colitis, post-operative or postpartum ileus, nausea and/or vomiting, decreased gastric motility and emptying, inhibition of the stomach, and small and/or large intestinal propulsion, increased amplitude of non-propulsive segmental contractions, constriction of sphincter of Oddi, increased anal sphincter tone, impaired reflex relaxation with rectal distention, diminished gastric, biliary, pancreatic or intestinal secretions, increased absorption of water from bowel contents, gastro-esophageal reflux, gastroparesis, cramping, bloating, abdominal or epigastric pain and discomfort, constipation, idiopathic constipation, post-operative gastrointestinal dysfunction following abdominal surgery, and delayed absorption of orally administered medications or nutritive substances.
10. The compound for use as a medicament as claimed in any one of claims 6 to 9, characterized in that the patient suffering from the disease is one receiving acute opioid therapy, such as a patient suffering from post-operative gastrointestinal dysfunction receiving acute opioid administration, or a subject receiving opioids chronically such as an AIDS patient, a cancer patient, a cardiovascular patient; a subject receiving chronic opioid therapy for pain management; or a subject receiving opioid therapy for maintenance of opioid withdrawal.
11. The compound for use as a medicament as claimed in any one of claims 6 to 10 in the treatment of pain, in the treatment of inflammatory conditions such as inflammatory bowel syndrome, in the treatment of infectious diseases, in the treatment of diseases of the musculoskeletal system such as osteoporosis, arthritis, osteitis, periostitis, myopathies, treatment of autoimmune diseases and immune suppression, therapy of postoperative gastrointestinal dysfunction following abdominal surgery, idiopathic constipation, and ileus, and in the treatment of disorders such as cancers involving angiogenesis, chronic inflammation and/or chronic pain, sickle cell anemia, vascular wounds, and retinopathy, and in the treatment of pruritus, psoriasis, psoriatic arthritis, contact dermatitis, atopic eczema, scleroderma, systemic lupus erythematous, urticaria, lichen planus, lymphoma and/or allergies.
12. A medicament comprising at least one compound as claimed in one of claims 1 to 5 or a solvate or hydrate thereof or a pharmaceutically acceptable salt thereof.
13. The medicament as claimed in claim 12, further comprising at least one opioid receptor agonist, preferably chosen from the group comprising alfentanil, anileridine, asimadoline, bremazocine, burprenorphine, butorphanol, codeine, CR845, dezocine, diacetylmorphine (heroin), dihydrocodeine, diphenoxylate, ethylmorphine, fedotozine, fentanyl, funaltrexamine, hydrocodone, hydromorphone, levallorphan, levomethadyl acetate, levomethadon, levorphanol. loperamide, meperidine ( pethidine), methadone, morphine. morphine-6-glucoronide, nalbuphine, nalorphine, nicomorphine, opium, oxycodone, oxymorphone, papavereturn, pentazocine, pethidin. piritramid, propiram, propoxyphene, remifentanyl, sufentanil, tilidine, trimebutine, and tramadol., and/or a steroidal anti- inflammatory drug, preferably chosen from the group of hydrocortisone, hydrocortisone acetate, prednisolone, methylprednisolone, prednisone, betamethasone, hydrocortisone- 17- valerate, betamethasone valerate, betamethasone dipropionate, prednicarbate, clobetasone-17- butyrate flunisolide, fluticasone propionate, triamcinolone acetonide, beclomethasone dipropionate, budesonide and/or hydrocortisone- 17-butyrate, and/or a nonsteroidal antiinflammatory drug (NSAID), preferably chosen from the group of aspirin, ibuprofen, diclofenac and/or naproxen, and/or an antibiotic.
14. A process for the preparation of a compound according to the general formula
(1) as claimed in one of claims 1 to 5, characterized in that the process comprises the following steps: a) reacting 5,6,7,8-tetrahydroquinoxalin-5-ol with a protection agent X-PG in the presence of a base to introduce a protecting group PG at the alcohol function, wherein X is a suitable leaving group; b) catalytically hydrogenating the PG protected 5,6,7, 8-tetrahydroquinoxalin-5-ol obtained in step a) under stereoselective reduction of the pyrazine ring to obtain PG protected cis-cis 5-hydroxy-decahydroquinoxaline; c) reacting the PG protected cis-cis 5-hydroxy-decahydroquinoxaline obtained in step b) with a reagent X-R1 to regioselectively introduce the substituent R1 at the 1-N atom of the cis-cis 5-hydroxy-decahydroquinoxaline, wherein X is a suitable leaving group; d) deprotecting the PG protected hydroxy group in the product obtained in step c) to provide for the corresponding α,β-aminoalcohol; e) reacting the α,β-aminoalcohol obtained in step d) with sulfuryl chloride in the presence of a base to provide for the corresponding 1,2,3-oxathiazolidine 2,2-dioxide; f) reacting the 1,2,3-oxathiazolidine 2,2-dioxide obtained in step e) with an amine
HNR 2 R 3 , followed by treatment with an acid to introduce the residue -NR 2 R 3 under inversion of the stereogenic center to provide for cis,trans 5-amino-octahydroquinoxaline; g) reacting the cis,trans 5-amino-octahydroquinoxaline obtained in step f) with an activated species ZACOY, wherein Y is a suitable leaving group, preferably with an acid chloride Z-ACOCl, under acylation in 4-position to provide for the compound of formula (1) together with its enantiomeric form; h) optionally separating the compound of formula (1) from its enantiomeric form; and i) optionally converting the compound of formula (1) obtained in step g) or step h) to pharmaceutically acceptable salts by reaction with the corresponding acid.
15. The process according to claim 14, further comprising the following reaction steps (al) and (a2) carried out before step a):
(al) oxidizing 5,6,7,8-tetrahydroquinoxalin-5-ol to the corresponding ketone with an oxidizing agent; (a2) subjecting the ketone obtained in step (al) to an asymmetric hydrogen transfer reaction using a hydrogenation agent and a chiral catalyst to provide for enantiomerically pure (S)-5,6,7,8-tetrahydroquinoxalin-5-ol, subjecting the (S)-5,6,7,8-tetrahydroquinoxalin-5-ol obtained in step (a2) to the reaction steps a) to i), to provide for compounds of formula (1) in enantiomerically pure form.
PCT/EP2014/060114 2013-05-17 2014-05-16 Perhydroquinoxaline derivatives useful as analgesics WO2014184356A1 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US201361824731P 2013-05-17 2013-05-17
EP13168204.9 2013-05-17
EP13168204 2013-05-17
US61/824,731 2013-05-17

Publications (1)

Publication Number Publication Date
WO2014184356A1 true WO2014184356A1 (en) 2014-11-20

Family

ID=48428382

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2014/060114 WO2014184356A1 (en) 2013-05-17 2014-05-16 Perhydroquinoxaline derivatives useful as analgesics

Country Status (1)

Country Link
WO (1) WO2014184356A1 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107098876A (en) * 2016-02-23 2017-08-29 江苏恒瑞医药股份有限公司 Phenylpropionyl amine derivant, its preparation method and its in application pharmaceutically
WO2017211272A1 (en) * 2016-06-07 2017-12-14 江苏恒瑞医药股份有限公司 Phenyl propanamide derivative, and manufacturing method and pharmaceutical application thereof
WO2019109934A1 (en) 2017-12-06 2019-06-13 江苏恒瑞医药股份有限公司 Salt of phenylpropionamide derivative and preparation method therefor
WO2019219019A1 (en) 2018-05-16 2019-11-21 江苏恒瑞医药股份有限公司 Pharmaceutical composition of kor receptor agonist
US11091497B2 (en) * 2017-12-08 2021-08-17 The Rockefeller University Pyrano[3,4-b]pyrazine kappa opioid receptor ligands for treating addiction, pruritus, pain, and inflammation
CN113712953A (en) * 2021-10-20 2021-11-30 济宁医学院附属医院 Pharmaceutical composition for rapidly healing osteoporotic fracture

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009080745A2 (en) 2007-12-20 2009-07-02 Westfälische Wilhelms Universität Münster Perhydroquinoxaline derivatives

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009080745A2 (en) 2007-12-20 2009-07-02 Westfälische Wilhelms Universität Münster Perhydroquinoxaline derivatives

Non-Patent Citations (5)

* Cited by examiner, † Cited by third party
Title
CHANG J. EUR. J. PHARMACOL., vol. 142, 1987, pages 197 - 205
ELLIOTT G.R.: "An automated method for registering and quantifying scratching activity in mice: use for drug evaluation", J. PHARMACOL. TOXICOL. METHODS, vol. 44, 2000, pages 453 - 459
GIJBELS M.J.: "Therapeutic interventions in mice with chronic proliferative dermatitis (cpdm/cpdm", EXP. DERMATOL., vol. 9, 2000, pages 351 - 358
OTTOSEN E.R., J. MED. CHEM., vol. 46, 2003, pages 5651 - 5662
WANG, J.B., FEBS LETT., vol. 338, 1994, pages 217 - 222

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107098876A (en) * 2016-02-23 2017-08-29 江苏恒瑞医药股份有限公司 Phenylpropionyl amine derivant, its preparation method and its in application pharmaceutically
CN107098876B (en) * 2016-02-23 2021-04-06 江苏恒瑞医药股份有限公司 Phenyl propionamide derivative, preparation method and medical application thereof
WO2017211272A1 (en) * 2016-06-07 2017-12-14 江苏恒瑞医药股份有限公司 Phenyl propanamide derivative, and manufacturing method and pharmaceutical application thereof
WO2019109934A1 (en) 2017-12-06 2019-06-13 江苏恒瑞医药股份有限公司 Salt of phenylpropionamide derivative and preparation method therefor
US11180530B2 (en) 2017-12-06 2021-11-23 Jiangsu Hengrui Medicine Co., Ltd. Salt of phenylpropionamide derivative and preparation method therefor
US11091497B2 (en) * 2017-12-08 2021-08-17 The Rockefeller University Pyrano[3,4-b]pyrazine kappa opioid receptor ligands for treating addiction, pruritus, pain, and inflammation
WO2019219019A1 (en) 2018-05-16 2019-11-21 江苏恒瑞医药股份有限公司 Pharmaceutical composition of kor receptor agonist
CN113712953A (en) * 2021-10-20 2021-11-30 济宁医学院附属医院 Pharmaceutical composition for rapidly healing osteoporotic fracture
CN113712953B (en) * 2021-10-20 2022-07-29 济宁医学院附属医院 Pharmaceutical composition for rapidly healing osteoporotic fracture

Similar Documents

Publication Publication Date Title
WO2014184356A1 (en) Perhydroquinoxaline derivatives useful as analgesics
JP4275945B2 (en) Kappa opioid receptor ligand
WO2014184355A1 (en) Perhydroquinoxaline derivatives useful as analgesics
US7563899B2 (en) (S)-N-methylnaltrexone
JP2010510326A (en) N-oxides of 4,5-epoxy-morphinanium analogs
JP2010510328A (en) (R) -N-stereoisomers of 7,8-saturated-4,5-epoxy-morphinanium analogs
JP3948026B2 (en) Brain cell protectant
PT2251330E (en) 4-hydroxybenzomorphans
EP1555266B1 (en) Remedies or preventives for urinary incontinence and morphinan derivatives having nitrogen-containing heterocyclic group
EP0657163A1 (en) Antitussive
AU2018359336B2 (en) Opioid receptor antagonist prodrugs
US5834478A (en) Morphinan hydroxamic acid compounds
KR20150007352A (en) Tricyclic compounds as kat ii inhibitors
US6770654B2 (en) Indole derivatives and use thereof in medicines
WO2016079109A1 (en) Process for the preparation of perhydroquinoxaline derivatives
TWI787392B (en) New benzimidazole derivatives as dual histamine h1 and histamine h4 receptor ligands
WO2001005795A1 (en) Remedies or preventives for frequent urination or urinary incontinence
KR20240018528A (en) Novel salts and crystals
AU2006249910B2 (en) (S)-N-methylnaltrexone, process for its synthesis and its pharmaceutical use

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 14724106

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 14724106

Country of ref document: EP

Kind code of ref document: A1