Title:
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Synthetic approaches to 9-azasteroids
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An account is given of total syntheses of azasteroids, syntheses of 4-piperidones, and also syntheses of 2-quinolizidones. l,2,3,4,5,6-Hexahydro-3-oxo-4aH-benzo[c]quinolizine was prepared and methylation shown to occur in the 2-position which was of no further synthetic value. 4-Cyano-l,2,3,4,5,6-hexahydro-3-oxo- 4aH-benzo[c]quinolizine was prepared and alkylated with bromo-acetone. Attempts to cyclise the product to produce the 9-azasteroid system were unsuccessful. l-Phenyl-4-piperidone was synthesised by a method giving a higher yield than reported in the literature, and some alkylation reactions carried out on it. Some reactions of compounds containing reactive hydrogens with quinoline-1-oxide in the presence of acetic anhydride are reported. Some 2-cyclopentyl quinoline derivatives are prepared by the action of cyclopentanone derivatives containing active hydrogens on quinoline-1-oxide in the presence of acetic anhdride or quinoline in the presence of acid chlorides. Attempts to construct ring C of the 9-azasteroid system from the 2-cyclopentyl quinoline derivatives have been investigated.
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