Patent AU-2002302419-B2 (AU)
Title: Substituted Pyrazolopyrimidines and thiazolopyrimidines used as analgesics
Inventor: IJZERMAN ADRIAAN P
IPC: A61P29/00
Filed: 2002-03-13
Granted: 2007-01-18
Abstract: Medicaments contain tetrahydro-pyrazolo (1,5-a) pyrimidine or 6,7-dihydro-5H-thiazolo (2,3-a) pyrimidine compounds (I) - (III). New medicaments contain pyrazolo- or thiazolo-pyrimidine compounds of formula (I) - (III) or their acid or base addition salts or solvates (specifically hydrates), in the form of racemates, pure stereoisomers (specifically enantiomers or diastereomers) or stereoisomer mixtures in any ratio. [Image] R 1, R 2H, OR 9, SR 1 0, 1-12C alkyl, cycloalkyl, cycloalkylmethyl, aryl, arylalkyl, heterocyclyl or heterocyclylalkyl; provided that one of R 1 and R 2 = H and the other is other than H, except that if one of R 1 and R 2 = aryl then the other = H or 1-12C alkyl; R 3, R 4H, 1-12C alkyl, cycloalkyl, cycloalkylmethyl, aryl or arylalkyl; provided that at least one of R 3 and R 4 = H; or one of R 1/R 2 plus one of R 3/R 4W', the other of R 1/R 2 and the other of R 3/R 4 being H or 1-12C alkyl; W' : (CH 2) n, CH=CHCH 2, CH 2CH=CH, CH=CHCH 2CH 2, CH 2CH=CHCH 2, CH 2CH 2CH=CH, O(CH 2) m, CH 2-oC 6H 4-CH 2, -oC 6H 4-CH 2, X-oC 6H 4- or -oC 6H 4-CH 2CH 2 (all with the left- and right-hand terminals bonded at the R 1/R 2 and R 3/R 4 positions respectively); or cyclopent-1-ene-3,5-diyl or cyclohexane-1,3-diyl: n : 3-6; m : 2-5; X : CH 2, O or S; R 51-12C alkyl, cycloalkyl, cycloalkylmethyl, aryl, arylalkyl, heterocyclyl, heterocyclylalkyl or C(O)R 1 1; R 6H, 1-8C alkyl, CN, halo, NO 2, NH 2, NHR 1 2, NR 1 3R 1 4, OR 1 5, S(O) pR 1 6, C(O)R 1 7 or -N=N-aryl; R 7H, 1-8C alkyl, CN, halo, NO 2, NH 2, NHR 1 2, NR 1 3R 1 4, OR 1 5, S(O) pR 1 9, C(O)R 1 7 or -N=N-aryl; R 8H, 1-8C alkyl or aryl; or R 7 + R 8C(R 2 1)=C(R 2 2)-C(R 2 3)=C(R 2 4); p : 0-2; R 9, R 1 0, R 1 5, R 1 6, R 1 8, R 1 9H, 1-8C alkyl, cycloalkyl, cycloalkylmethyl, aryl or arylalkyl; R 1 1H, 1-8C alkyl, cycloalkyl, cycloalkylmethyl, aryl or OR 2 5; R 1 2alkyl or arylmethyl; R 1 3, R 1 4alkyl; or R 1 3 + R 1 4(CH 2) h; h : 4 or 5; R 1 7as R 9; or NH 2, NHR 1 2, NR 1 3R 1 4 or OR 2 6; R 2 0as R 9; or OR 2 7; R 2 1 - R 2 4H, halo or OR 2 8; R 2 5 - R 2 8H or alkyl, provided that R 2 5 is not H if R 1 = aryl and R 2 = alkyl; unless specified otherwise alkyl groups have 1-6C and cycloalkyl groups 3-8C. Independent claims are included for: (i) the preparation of (I) - (III); (ii) (I) - (III) (including salts, solvates, stereoisomers etc.) as new compounds, with the exception of: 4,5,6,7-tetrahydro-2-methyl-5,7-diphenyl-pyrazolo (1,5-a) pyrimidine; 4,5,6,7-tetrahydro-2,5-dimethyl-7-phenyl-pyrazolo (1,5-a) pyrimidine; 4,5,6,7-tetrahydro-5,7-methyl-3-phenyl-pyrazolo (1,5-a) pyrimidine; 4,5,6,7-tetrahydro-2,5,7-trimethyl-pyrazolo (1,5-a) pyrimidine; 4,5,6,7-tetrahydro-5,7-dimethyl-2-phenyl-pyrazolo (1,5-a) pyrimidine; 4,5,6,7-tetrahydro-2-methyl-5,7-di-n-propyl-pyrazolo (1,5-a) pyrimidine-3-carbonitrile; 4,5,6,7-tetrahydro-5-methyl-7-(3-(trifluoromethyl)-phenyl)-pyrazolo (1,5-a) pyrimidine-3-carbonitrile; 7-(3- or 4-chlorophenyl)-4,5,6,7-tetrahydro-5-methyl-pyrazolo (1,5-a) pyrimidine-3-carbonitrile; 3,4-dihydro-2-(4-nitrophenyl)-4-phenyl-2H-pyrimido (2,1-b) benzothiazole; and 3,4-dihydro-4-(4-methylphenyl)-2-(4-nitrophenyl)-2H-pyrimido (2,1-b) benzothiazole; and (iii) combinatorial libraries containing the new compounds as in (ii). ACTIVITY : Analgesic; anticonvulsant; neuroleptic; neuroprotective; nootropic; antiparkinsonian; cerebroprotective; vasotropic; anti-HIV; auditory; respiratory; cytostatic; antiarrhythmic; immunoregulator; nephrotropic; antiinflammatory; hypnotic; thrombolytic; anticoagulant; uropathic; antidiabetic; antipsoriatic; ophthalmological. MECHANISM OF ACTION : Nucleoside transport protein ligand; adenosine kinase ligand; adenosine deaminase ligand; A 1, A 2 and/or A 3 receptor ligand. In particular the compounds bind to the MK801 binding site of the NMDA receptor. 7-(3,4-Dimethoxyphenyl)-2-methylsulfanyl-5-phenethyl-tetrahydro-pyrazolo (1,5-a) pyrimidine-3-carbonitrile (Ia) had K i 0.3 MicroM in a nucleoside transport protein inhibition assay.