Synthesis, Spectrum, Crystal Structure and Antibacterial Activities of New Polydentate Schiff Base Ligands Containing a Pyridine Ring and Amide Moieties

Abstract

Using highly dilute method and 5-fold excess of diamine a new acyclic diamine containing pyridine moiety, N, N'-bis(2-aminoethyl)-2,6-pyridinedicarbamide (1a) was synthesized. Six novel linear polydentate Schiff base ligands containing pyridine and amide moieties, and N,N'-bis(γ-salicylideneaminopropyl)-2,6pyridinedicarbamide (2f) have been synthesized and characterized by elemental analysis, IR, UV-Vis, MS and 1 H NMR methods. The single-crystal analysis of 2e showed that it belongs to triclinic system with P-1 space group and the unit cell parameters: a＝11.010 (2) nm, b＝13.865(3) nm, c＝9.6537(19) nm, α＝102.77(2)°, β＝92.07(3)°, γ＝ 87.98(3)°, V＝1435.7(5) nm 3 , Z＝2, D c ＝1.230 mgּcm -3 , M r ＝531.66. In addition, microcalorimetric test of the inhibitory capacities of these compounds for E. coli has shown that they have antibacterial activity to different extent and that of salicylidene Schiff base is the best. The structure-activity relationship has been primarily discussed.

Synthesis of new acyclic chelators H4aPyta and H6aPyha and their complexes with Cu2+, Ga3+, Y3+, and Bi3+

“…Compound 2 was prepared according to a modified procedure. [50][51][52] Ethylenediamine (2.463 g, 40.984 mmol) was added to a solution of dimethyl 2,6-pyridinedicarboxylate 1 (200 mg, 1.025 mmol) in MeOH (15 mL). The mixture was stirred at room temperature for 19 hours and refluxed for 1 hour in an argon atmosphere.…”

Antibacterial activity and structure-activity relationships of Schiff bases on Staphylococcus aureus by microcalorimetry

“…In a previous work, we found out that the synthesized polydentate Schiff bases containing pyridine and amide moieties processed some inhibitory capacity on E. coli [19] . Using microcalorimetric method, the present paper investigated the growth of S. aureus under the action of the six Schiff bases.…”