Three novel chiral packing materials for high-performance liquid chromatography were prepared by covalently binding of (2S)-N-(3,5-dimethylphenyl)-2-[(4-chloro-3,5-dinitrophenyl)carbonylamino]propan-amide (7), (2S)-N-(3,5-dimethylphenyl)-2-[(4-chloro-3,5-dinitrophenyl)carbonylamino]-4-methylpentanamide (8), and (2S)-N-(3,5-dimethylphenyl)-2-[(4-chloro-3,5-dinitrophenyl)carbonyl-amino]-2-phenylacetamide (9) to aminopropyl silica. The resulting chiral stationary phases (CSPs 1-3) proved effective for the resolution of racemic 4-aryl-3,4-dihydro-2(1H)-pyrimidone derivatives (TR 1-14). The mechanism of their enantioselection, supported by the elution order of (S)-TR 13 and (R)-TR 13 and molecular modeling of the complex of the slower running (S)-TR 13 with CSP 1 is discussed.

2-Methyl-3H-indoles 1 cyclize with two equivalents of ethyl malonate 2 to form 4-hydroxy-11Hbenzo [b]pyrano[3,2-f]indolizin-2,5-diones 3, whereas 2-methyl-2,3-dihydro-1H-indoles 9 give under similar conditions regioisomer 8-hydroxy-5-methyl-4,5-dihydro-pyrrolo[3,2,1-ij]pyrano[3,2-c]quinolin-7,10diones 10. The pyrone rings of 3 and 9 can be cleaved either by alkaline hydrolysis to give 7-acetyl-8hydroxy-10H-pyrido[1,2-a]indol-6-ones 4 or 5-acetyl-6-hydroxy-2-methyl-1,2-dihydro-4H-pyrrolo-[3,2,1-ij]quinolin-4-ones 11, respectively. Chlorination of 3 and 9 with sulfurylchloride gives under subsequent ring opening 7-dichloroacetyl-8-hydroxy-10H-pyrido[1,2-a]indol-6-ones 5 or 5-dichloracetyl-6hydroxy-2-methyl-1,2-dihydro-4H-pyrrolo[3,2,1-ij]quinolin-4-ones 12. The dichloroacetyl group of 5 can be reduced with zinc to 7-acetyl-8-hydroxy-10H-pyrido[1,2-a]indol-6-ones 7. Treatment of the acetyl compounds 4, 7 and 11 with 90% sulfuric acid cleaves the acetyl group and yields 8-hydroxy-10H-pyrido[1,2-a]indol-6-ones 6 and 8, and 6-hydroxy-2-methyl-1,2-dihydro-4H-pyrrolo[3,2,1-ij]quinolin-4-ones 13. Reaction of dichloroacetyl compounds 12 with sodium azide yields 6-hydroxy-2-methyl-5-(1H-tetrazol-5ylcarbonyl)-1,2-dihydro-4H-pyrrolo[3,2,1-ij]quinolin-4-ones 14 via intermediate geminal diazides.

Fused pyridine derivativesFused pyridine derivatives R 0450 Organic Azides in Heterocyclic Synthesis. Part 32. Synthesis and Reactions of 11H-Benzo[b]pyrano[3,2-f]indolizines and Pyrrolo[3,2,1-ij]pyrano[3,2-c]quinolines. -Cyclocondensation of 2-methylindoles (I) with malonate (II) affords benzopyranoindolizine derivatives (III), whereas similar reaction of related dihydro-1H-indoles (IX) with (II) results in the formation of pyrrolopyranoquinolines (X). The pyrone ring in both reaction products can be cleaved by alkaline hydrolysis as well as chlorination with sulfuryl chloride. -(KAPPE, T.; ROSCHGER, P.; SCHUIKI, B.; STADLBAUER*, W.; J. Heterocycl. Chem. 40 (2003) 2, 297-302; Dep. Chem., Karl-Franzens-Univ., A-8010 Graz, Austria; Eng.) -D. Singer 35-120 2003 Fused pyridine derivatives

Abstract4a-Methyl-2,3,3,4a-tetrahydro-1H-carbazoles 3, obtained from arylhydrazines 1 and 2-methylcyclohexanone 2, react with diethyl malonate 5a by cyclocondensation to 7-hydroxy-13b-methyltetrahydro-pyrano[2',3':4,5]pyrido[3,2,1-jk]carbazolediones 6. With methanetricarboxylates 5b,c, cyclocondensation forms a mixture of pyrano-pyrido-carbazole-carboxylates 7 and pyrido-carbazolecarboxylates 8. Degradation of pyrano-pyrido-carbazolediones 6 by alkaline ring-opening and decarboxylation leads to 5-acetyl derivatives 10. Deacetylation with sulfuric acid reveals the 5-unsubstituted 4-hydroxy-11b-methyl-1,2,3,11b-tetrahydro-6H-pyrido[3,2,1-jk]carbazol-6-one (9). Pyridocarbazolone 9 was also obtained in a single step reaction from tetrahydrocarbazole 3a and malonic acid 5d with phosphoryl chloride as catalyst in low yields.Electrophilic halogenation of 9 takes place at position 5 and gives 5-bromo compound 15 or 5,5-dihalogenated products 14, 16 or 17, depending on the reaction conditions. Nitration takes also place in an electrophilic reaction to give 4-hydroxy-5-nitro-pyrido-carbazolone 20. Nucleophilic exchange of the 4-hydroxy group in pyridocarbazolones 9 and 20 by reaction with phosphoryl chloride gives reactive 4-chloro intermediates 18 and 21, which react with sodium azide to 4-azido derivatives 19 and 22. 4-Azido-5-nitro-pyrido-carbazolone 22 with the reactive ortho-nitro group in the neighborship of the azido group cyclizes thermolytically to furoxane 23. This reaction was studied by differential scanning calorimetry (DSC).

Arylhydrazines 1 react with 2-methylcyclohexanone 2 via Fischer indole synthesis to 4a-methyl-2,3,3,4a-tetrahydro-1H-carbazoles 3, which cyclize with 2-substituted malonates 5 to give 5-aryl-and 5-alkylsubstituted 4-hydroxy-11b-methyl-1,2,3,11b-tetrahydro-6H-pyrido[3,2,1-jk]carbazol-6-ones 6. Pyridocarbazoles 6 can be shown to give a series of reactions, such as electrophilic halogenation to 5-chloro-pyridocarbazole-4,6-dione 9, and nucleophilic halogenation to 4-chloro-pyridocarbazol-6-one 11. 4-Azido-5-phenylpyridocarbazol-6-one 13 cyclizes under thermolysis to the indolo derivative 14. This reaction was studied by differential scanning calorimetry (DSC).