Synthesis And Characterization Of Heterocyclic Compounds Based 5-ethylisatin

Isatin, 1H-indole-2,3-dione, is a heterocyclic compound of meaning importance in medicine chemistry. It is a synthetically versatile molecule, a precursor for a large number of pharmacologically active compounds. Isatin and its derivatives have aroused great attention in recent years due to their variety of biological activities. Therefore, it is extremely important to synthesis the heterocyclic compounds based 5-ethylisatin. This thesis is mainly divided into five parts.In the first part, chemical properties and biological activity of isatin and its derivatives were reviewed through consulting a number of literature about isatin.In the second part, the synthesis of 9H-pyrimido[4,5-b]indole-2-amines derivatives were described. 4-ethylaniline were first underwent the Sandmeyer reaction to give 5-ethylisatin 1; 5-ethylisatin 1 were underwent by hydrazine hydrate reduction into 5-ethyllindolin-2-one 2; the synthesis of 2-chloro-5-ethyl-1H-indole-3-carbaldehyde and 2-chloro-5-ethyl-1H-indole-3-acetyl 3m/3n were obtained first use DMF or DMA with phosphorus oxychloride form Vilsmeier-Haack reagent, then respectively reacwith 2; which were in acetone further alkylated to give the corresponding N-substitutted-2-chloro-5-ethyl-3-(carbaldehyde)acetylindole 4a-4j in good yields; compound 4a-4j were underwent the condensation and cycliztion reaction with guanidine nitrate under alkaline conditions to give target compounds 5a-5j.In the third part, the synthesis of(E)-2-chloro-5-ethyl-1-substitued-1H-indole-3-carbaldehyde(ethanoyl) oxime and(E)-5-ethyl-1-substitued-2-phenoxy-1H-indole-3-carbaldehyde(ethanoyl) oxime. Compound 4a-4j were reacted with phenol using DMF as solvent with the presence of KOH to obtain 1-substitued-5-ethyl-2-phenoxy-1H-indol-3-carbaldehyde and 1-(1-substitued-5-ethyl-2-phenoxy-1H-indol-3-yl) ethanone 6a-6j; then the compound 4a-4j and 6a-6j were respectively reacted with hydroxylamine hydrochloride to synthesize 20 kinds of oximes 7a-7j and 8a-8j.In the fourth part, the synthesis of substituted-9-ethyl-6-methyl-6H-indole[2,3-b] quinoline derivatives were described. 1-(2-chloro-5-ethyl-1H-indole-3-yl) ethanone 4f were reacted with substituted isatin using 10% ethanol-water as solvent with the presence of KOH to successfully synthesize a series of target compounds 9a-9g.In the fifth part, the synthesis of substituted-5-methyl-5H-indole[2,3-b]quiniline were described. Compound 3a-3k were heated at reflux in neat N-methylaniline for 3min depending on the substituent at the carbonyl group, a nucleophilic substitution and subsequent intramolecular cyclization led to the hydrochloride salts 3a,-3k, were isolated; subsequent treatment with sodium bicarbonate released 10a-10 k in good yields of 60.3-78.8%.