Synthesis and structural characterization of new bis(alkynylamidinato)lanthanide(III)-amides

Synthesis, antimicrobial, anti-cancer and in silico studies of new urea derivatives

The reaction of an alkyl or aryl isocyanates with some primary amines in acetonitrile at room temperature afforded the corresponding alkyl- and aryl-urea derivatives. All the prepared urea compounds have been elucidated by FTIR, NMR, and elemental analysis. The compounds 1 and 3 were confirmed by single-crystal X-ray diffraction. The 4-tolylsulfonyl isocyanate reacted with the aryl amines 1, 2, 3, and 2,4-dichloroaniline to afford the corresponding sulfonylurea derivatives 5-8. Likewise, the reaction of the isocyanates with 2,4-dichloroaniline, 5-methyl isoxazole-3-amine, and 2-aminothiazole derivatives gave the corresponding urea derivatives 9-17. All the prepared compounds 5-17 were tested in vitro as anti-microbial and anti-HepG2 agents. Moreover, analyzing gene expression of TP53-exon4 and TP53-exon7, DNA damage values, and DNA fragmentation percentages have been discussed. The compounds 5 and 8 recorded the highest activity against the tested microbial strains with maximum activity against C. albicans (50 mm) and B. mycoides (40 mm), respectively. The compounds 5 inhibited the growth of E. coli, S. aureus, and C. Albicans at the MIC level of 0.0489 µM, while the compound 8 was able to inhibit the visible growth of E. coli and C. albicans at MIC value of 3.13 µM and S. aureus at 0.3912 µM. In the same line, compound 5 showed the best cytotoxic activity against the HepG2 cell line (IC₅₀ = 4.25 µM) compared to 5 fluorouracil with IC₅₀ = 316.25 µM. Expression analysis of liver cancer related to a gene including TP53-exon4 and TP53-exon7 was used in HepG2 Liver cancer cell lines using RT-qPCR. The expression values of TP53-exon4 and TP53-exon7 genes were decreased. The DNA damage values and DNA fragmentation percentages were increased significantly (P < 0.01) in the treated HepG2 (5) sample compared with the negative control. Docking studies were performed for the synthetic compounds against 2 bacterial proteins (DNA gyrase subunit B, and penicillin binding protein 1a) that are known targets for some antibiotics, and one cell division protein kinase 2 (CDK2) as target for anticancer drugs.

Synthesis and structural characterization of four di-chlorido-bis-(cyclo-propyl-alkynyl-amidine)-metal complexes

Deliberate hydrolysis of lithium cyclo-propyl-alkynylamidinates, Li[c-C3H5-C≡C(NR')2] [R' = i Pr, Cy = cyclo-hex-yl)], afforded the hitherto unknown neutral cyclo-propyl-alkynyl-amidine derivatives c-C3H5-C≡C-C(NR')(NHR') [R' = i Pr (1), Cy (2)]. Subsequent reactions of 1 or 2 with metal(II) chlorides, MCl2 (M = Mn, Fe, Co), provided the title complexes di-chlorido-bis-(3-cyclo-propyl-N,N'-diisopropyl-prop-2-ynamidine)-manganese(II), [MnCl2(C12H20N2)2], (3), di-chlorido-bis-(3-cyclo-propyl-N,N'-diisopropyl-prop-2-ynamidine)-iron(II), [FeCl2(C12H20N2)2], (4), di-chlorido-bis-(N,N'-di-cyclo-hexyl-3-cyclo-propyl-prop-2-ynamidine)-iron(II), [FeCl2(C18H28N2)2], (5), and di-chlorido-bis-(N,N'-di-cyclo-hexyl-3-cyclo-propyl-prop-2-ynamidine)-cobalt(II), [CoCl2(C18H28N2)2], (6), or more generally MCl2[c-C3H5-C≡C-C(NR')(NHR')]2 [R' = i Pr, M = Mn (3), Fe (4); R' = Cy, M = Fe (5), Co (6)] in moderate yields (30-39%). Besides their spectroscopic data (IR and MS) and elemental analyses, all complexes 3-6 were structurally characterized. The two isopropyl-substituted complexes 3 and 4 are isotypic, and so are the cyclo-hexyl-substituted complexes 5 and 6. In all cases, the central metal atom is coordinated by two Cl atoms and two N atoms in a distorted-tetra-hedral fashion, and the structure is supported by intra-molecular N-H⋯Cl hydrogen bonds.

Crystal structures of two ytterbium(III) complexes comprising alkynylamidinate ligands

Two ytterbium(III) complexes comprising alkynylamidinate ligands, namely bis-(η5-cyclo-penta-dien-yl)(3-cyclo-propyl-N,N'-diiso-propyl-propynamidinato-κ2N,N')ytterbium(III), [Yb(C5H5)2(C12H19N2)] or Cp2Yb[( i Pr2N)2C-C≡C-c-C3H5] (1) and tris-(3-phenyl-N,N'-di-cyclo-hexyl-propynamidinato-κ2N,N')ytterbium(III), [Yb(C21H27N2)3] or Yb[(CyN)2C-C≡C-Ph]3 (Cy = cyclo-hex-yl) (2) have been synthesized and structurally characterized. Both complexes are monomers; for complex 2, the contribution to the scattering from highly disordered toluene solvent molecules in these voids was removed with the SQUEEZE routine [Spek (2015). Acta Cryst. C71, 9-18] in PLATON. The stated crystal data for Mr, μ etc. do not take these into account.

Five different types of η8-cyclooctatetraenyl-lanthanide half-sandwich complexes from one ligand set, including a “giant neodymium wheel”

Using one ligand set, five different types of η⁸-cyclooctatetraenyl-lanthanide half-sandwich complexes, including a “giant neodymium wheel”, have been prepared and structurally characterized.