Synthesis And Biological Activities Of Novel Nitrogen-Containing Heterocyclic Compounds

The novel heterocyclic compounds especially nitrogen-containing heterocyclic compounds have become to be the mainstream of creation of pesticide and medicine based on their structures are similar to the alkaloids' body, such as purine, pyrimidine, etc. They also have a high specificity to the target, and have excellent environmental compatibility. Thereinto the derivatives of 1,2,4-triazole compound and homocysteine thiolactone exhibit excellent biological activities. They have been widely used in pesticide and medicine due to their high efficiency, low toxicity and inward absorbent features. In order to search for new fungicides with broad spectrum and high activity and to explore the relationship between their structures and biological activities, 16 Schiff bases of 1,2,4-triazole and 7 derivatives of pyridinecarboxylamide have been synthesized. Their structures were confirmed by IR, ~1H NMR and elemental analysis. The preliminary biological activities have been tested. The relationship between the structures and the fungicidal activities of the compounds has been discussed.Part one: eight Schiff bases of 3-amino- 1,2,4-triazole derivatives and eight Schiff bases of 5-aminol-l,2,4-triazole-3- formic acid derivatives have been synthesized by condensation 3-amino-1,2,4-triazole and 5-aminol-l,2,4-triazole-3-formic acid with substituted aromatic aldehydes using the methods of solvent and solvent-free. Their structures have been confirmed by IR, ~1H NMR and elemental analysis. The preliminary biological activities have been tested. The results showed that most of the compounds exhibited excellent fungicidal activities to four vegetable pathogens. The relationship between the structures and the biological activities has been discussed.Part two: seven derivatives of pyridinecarboxylamide were prepared by reaction of DL-homocysteine thiolactone hydrochloride (ADT.HC1) with substituted pyridinecarboxylic acids. Their structures have been confirmed by IR, ~1H NMR and elemental analysis. The preliminary biological activities indicated that the title compounds showed different extent fungicidal activities to four vegetable pathogens. The relationship between the structures and the fungicidal activities of the compounds has been discussed.