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Adding to the versatile class of ionic liquids, we report the detailed structure and property analysis of a new class of asymmetrically substituted imidazolium salts, offering interesting thermal characteristics, such as liquid crystalline behavior, polymorphism or glass transitions. A scalable general synthetic procedure for N-polyaryl-N’-alkyl-functionalized imidazolium salts with para-substituted linker (L) moieties at the aryl chain, namely [LPhmImHR]+ (L=Br, CN, SMe, CO2Et, OH; m=2, 3; R=C12, PEGn; n=2, 3, 4), was developed. These imidazolium salts were studied by single-crystal X-ray diffraction (SC-XRD), NMR spectroscopy and thermochemical methods (DSC, TGA). Furthermore, these imidazolium salts were used as N-heterocyclic carbene (NHC) ligand precursors for mononuclear, first-row transition metal complexes (MnII, FeII, CoII, NiII, ZnII, CuI, AgI, AuI) and for the dinuclear Ti-supported Fe-NHC complex [(OPy)2Ti(OPh2ImC12)2(FeI2)] (OPy=pyridin-2-ylmethanolate). The complexes were studied concerning their structural and magnetic behavior via multi-nuclear NMR spectroscopy, SC-XRD analyses, variable temperature and field-dependent (VT-VF) SQUID magnetization methods, X-band EPR spectroscopy and, where appropriate, zero-field 57Fe Mössbauer spectroscopy.

The metabolism of SCH 40120, which is the clinically effective antipsoriatic drug 10-(3-chlorophenyl)-6,8,9,10-tetrahydrobenzol[b][1,8]naphthyrid in-5(7H)-one, was determined in vitro. Rat, dog, cynomolgus monkey, and human liver slices hydroxylated the aliphatic, cyclohexenyl ring of the drug and conjugated the resulting carbinol. The identified metabolites comprised the corresponding 6-, 7-, and 9-carbinols, the glucuronide of the 6-carbinol, and the 6-ketone derived from the parent drug. Although the three carbinols appeared in the liver isolates of all species studied, the relative amounts of these metabolites varied across species. With a high, non-physiological ratio of substrate to liver, the 6-carbinol and its glucuronide were the major metabolites in human and monkey, whereas the 6-ketone was a minor metabolite in dog. Containing a stereogenic axis and center, the 6-carbinol existed as diastereomeric atropisomers. Its structure was established by 13C and 1H NMR spectroscopy, mass spectrometry, and comparison to an authentic sample.

2-Arylamino-3-pyridinecarbonyl chlorides acylated the β-carbon atoms of enamines, and the resulting enaminones cyclized to give a series of fused polycyclic N-aryl pyridones. The series included 10-(3-chlorophenyl)-6,8,9,10-tetrahydrobenzo[b][1,8]naphthyridin-5(7H)-one (Sch 40120), an antipsoriatic agent.

Ammonium formate in the presence of palladium on carbon in methanol reacted with (S)-(+)4-(2-Amino-3-chloropropyl)-imidazole to give optically pure (R)-(−)-α-methyl histamine at atmospheric pressure.

2-methylthio-2-imidazoline and 2-methylthio-1,4,5,6-tetrahydro-2-pyrimidine amidated 2-chloro-3-pyridine- and 2-chloro-3-pyrazinecarbonyl chlorides. The products reacted with aromatic amines forming a series of tricyclic, linearly fused N-aryl pyrimidones. Included among these pyrimidones were 10-aryl-2,3-dihydroimidazo[1,2-a]pyrido[2,3-d]pyrimidin-5(10H)-ones, 11-aryl-2,3,4,11-tetrahydropyrido-[2,3-d]pyrimido[1,2-a]pyrimidin-6(6H)-ones, 10-aryl-2,3-dihydroimidazo[1,2-a]pyrazino[2,3-d]pyrimidin-5(10H)-ones and 11-aryl-2,3,4,11-tetrahydropyrimido-[1,2-a]pyrazino[2,3-d]pyrimidin-6(6H)-ones. 4,5,6,7-Tetrahydro-2-(mythylthio)-1H-1,3-diazepine amidated the ethyl hydrogen carbonate of 2-(phenylamino)-3-pyridinecarboxylic acid, forming 12-phenyl-2,3,4,5-tetrahydropyrido[2',3':4,5]pyrimido[1,2-a][1,3]diazepine-7(12H)-one. A single crystal X-ray analysis and an unambiguous synthesis established the structure of the linearly fused isomer 10-phenyl-2,3-dihydroimidazo[1,2-a]pyrido[2,3-d]pyrimidin-5(10H)-one.

2-methylthio-2-imidazoline and 2-methylthio-1,4,5,6-tetrahydro-2-pyrimidine amidated 2-chloro-3-pyridine- and 2-chloro-3-pyrazinecarbonyl chlorides. The products reacted with aromatic amines forming a series of tricyclic, linearly fused N -aryl pyrimidones. Included among these pyrimidones were 10-aryl-2,3-dihydroimidazo[1,2- a ]pyrido[2,3- d ]pyrimidin-5(10 H )-ones, 11-aryl-2,3,4,11-tetrahydropyrido-[2,3- d ]pyrimido[1,2- a ]pyrimidin-6(6 H )-ones, 10-aryl-2,3-dihydroimidazo[1,2- a ]pyrazino[2,3- d ]pyrimidin-5(10 H )-ones and 11-aryl-2,3,4,11-tetrahydropyrimido-[1,2- a ]pyrazino[2,3- d ]pyrimidin-6(6 H )-ones. 4,5,6,7-Tetrahydro-2-(mythylthio)-1 H -1,3-diazepine amidated the ethyl hydrogen carbonate of 2-(phenylamino)-3-pyridinecarboxylic acid, forming 12-phenyl-2,3,4,5-tetrahydropyrido[2',3':4,5]pyrimido[1,2- a ][1,3]diazepine-7(12 H )-one. A single crystal X-ray analysis and an unambiguous synthesis established the structure of the linearly fused isomer 10-phenyl-2,3-dihydroimidazo[1,2- a ]pyrido[2,3- d ]pyrimidin-5(10 H )-one.

2-Arylamino-3-pyridinecarbonyl chlorides acylated the β-carbon atoms of enamines, and the resulting enaminones cyclized to give a series of fused polycyclic N-aryl pyridones. The series included 10-(3-chlorophenyl)-6,8,9,10-tetrahydrobenzo[b][1,8]naphthyridin-5(7H)-one (Sch 40120), an antipsoriatic agent.

1-Phenylmethyl- and 1-(4-methoxyphenylmethyl)-5-chloro-1,2,3-triazole-4-carbonyl chlorides acylated the pyrrolidine enamines of cyclopentanone and cyclohexanone, and the resulting enaminones underwent transaminations with aryl amines under acidic conditions. The products then cyclized under basic conditions to linearly fused, tricyclic 3-phenylmethyl- and 3-(4-methoxyphenylmethyl)-4-aryl-8-oxo-4,5,6,7-tetrahydrocyclopenta[6]-1,2,3-triazolo[4,5-e]pyridines, and to 5,6,7,8-tetrahydro-4-aryl-3H-1,2,3-triazolo[4,5-b]quinolin-9(4H)-ones. Similar transaminations afforded the related 8-phenyl- and 8-(3-chlorophenyl)-1,5,7,8-tetrahydro-1-(phenylmethyl)-4H-thieno[3,4-e]-1,2,3-triazolo[4,5-b]pyridin-4-ones. Phase-transfer and catalytic hydrogenolyses of some of these intermediates furnished 4-aryl-8-oxo-4,5,6,7-tetrahydrocyclopenta[b]-1,2,3-triazolo[4,5-e]pyridines and 4-aryl-5,6,7,8-tetrahydro-3H,2,3-triazolo[4,5-b]quinoline-9-(4H)-ones. The 3-(4-methoxyphenylmethyl)-4-aryl intermediates were sterically crowded. Two protons from the methoxyphenylmethylphenylmethylgroups were dramatically shielded because of anisotropic effects exerted by the 4-aryl substituents.

Arylmethylimidazolines and (3-chlorophenyl)methyl-1,4,5,6-tetrahydropyrimidine amidated 2-chloro-3-pyridinecarbonyl chloride and potassium t-butoxide cyclized the products to linearly fused, tricyclic imidazo-and pyrimido[1,2-g][1,6]naphthyridinones. Condensation of ethyl 2-chloro-3-pyridinecarboxylate with 2-(phenylmethyl)imidazoline in the presence of sodium methoxide directly formed the isomeric, angularly fused 8,9-dihydro-6-phenylimidazo[1,2-a][1,8]naphthyridin--5(7H)-one.

The structural modification of the benzylic ether region of oxime 1 has resulted in the identification of several novel aryl amides as selective or dual NK 1 /NK 2 antagonists.

1-Phenylmethyl- and 1-(4-methoxyphenylmethyl)-5-chloro-1,2,3-triazole-4-carbonyl chlorides acylated the pyrrolidine enamines of cyclopentanone and cyclohexanone, and the resulting enaminones underwent transaminations with aryl amines under acidic conditions. The products then cyclized under basic conditions to linearly fused, tricyclic 3-phenylmethyl- and 3-(4-methoxyphenylmethyl)-4-aryl-8-oxo-4,5,6,7-tetrahydrocyclopenta[6]-1,2,3-triazolo[4,5-e]pyridines, and to 5,6,7,8-tetrahydro-4-aryl-3H-1,2,3-triazolo[4,5-b]quinolin-9(4H)-ones. Similar transaminations afforded the related 8-phenyl- and 8-(3-chlorophenyl)-1,5,7,8-tetrahydro-1-(phenylmethyl)-4H-thieno[3,4-e]-1,2,3-triazolo[4,5-b]pyridin-4-ones. Phase-transfer and catalytic hydrogenolyses of some of these intermediates furnished 4-aryl-8-oxo-4,5,6,7-tetrahydrocyclopenta[b]-1,2,3-triazolo[4,5-e]pyridines and 4-aryl-5,6,7,8-tetrahydro-3H,2,3-triazolo[4,5-b]quinoline-9-(4H)-ones. The 3-(4-methoxyphenylmethyl)-4-aryl intermediates were sterically crowded. Two protons from the methoxyphenylmethylphenylmethylgroups were dramatically shielded because of anisotropic effects exerted by the 4-aryl substituents.

Potassium carbonate in methanol saponified the acetate ester groups of certain meta-acetoxylated α-benzamido ketones and cyclized the resulting phenols in situ to give a series of hydroxylated isoquinolinones and derivatives

Arylmethylimidazolines and (3-chlorophenyl)methyl-1,4,5,6-tetrahydropyrimidine amidated 2-chloro-3-pyridinecarbonyl chloride and potassium t-butoxide cyclized the products to linearly fused, tricyclic imidazo-and pyrimido[1,2-g][1,6]naphthyridinones. Condensation of ethyl 2-chloro-3-pyridinecarboxylate with 2-(phenylmethyl)imidazoline in the presence of sodium methoxide directly formed the isomeric, angularly fused 8,9-dihydro-6-phenylimidazo[1,2-a][1,8]naphthyridin--5(7H)-one.

N-Oxidation of 2-methyl-3β-phenyl-2,3α,3aβ,6aβ-tetrahydrothieno [2,3-d] isoxazole-4,4-dioxide (1) gave a nitrone (2) which underwent an intramolecular 1,3-dipolar cycloaddition yielding a tricyclic isoxazolidine (4). A single-crystal X-ray analysis unequivocally established the structure of 4 as 9β-phenyl-2-oxa-6-thia-1-azatricyclo[3.3.1.03,7]nonan-4α-o1-6,6-dioxide. LiA1H4 and LiA1D4, reduced 4 exhaustively and rearranged it profoundly to isotopomers 5 and 6, respectively ; a novel Grob fragmentation may have mediated the rearrangement. Inter alia, measurements of 13C-13C coupling constants and of m z ratios of fragment ions yielded the complete structures of 5 and 6. They are 5β-phenyl-8-thia-6-azabicyclo[3. 3. 1]octan-2α-o1 and its 3α-deuterio analog, respectively.