Design,synthesis, cytotoxicity and molecular modeling studies of some novel fluorinated pyrazole-based heterocycles as anticancer and apoptosis-inducing agents

Molecular Diversity - 3,5-Diamino-4-(3-trifluoromethylphenyldiazenyl)-1H-pyrazole was used as a starting scaffold for the synthesis of new pyrazole-based heterocycles to study their effects on the...     

N-2-[3-methylpyridyl]-N′-phenylthiourea transition metal complexes

New complexes of N-2-[3-methylpyridyl]-N-phenylthiourea (HMPyPT) have been prepared from Ni^II, Cu^II, Zn^II, Pd^II, Pt^IV and Au^III chlorides. Three types, containing 1:1, 1:2 and 1:3 metal–ligand ratios, were isolated and characterized. In every case the ligand behaves in a monodentate manner coordinating via the pyridyl nitrogen. Attempts to isolate complexes containing the deprotonated ligand by raising the pH of the reaction mixture from 1.6–5.5 to 8.5 were unsuccessful. The bonding modes and the stereochemistry of the metal complexes have been determined from spectral (i.r., u.v.–vis., ¹H-n.m.r.) and magnetic measurements. The results suggest a square-planar structure for the Pd^II and Au^III complexes, but octahedral geometry for the other metal complexes. Thermal analysis (d.t.a., t.g.a.) measurements on the solid complexes have also been conducted.     

Exploration of quinoxaline derivatives as antimicrobial and anticancer agents

Novel 2 and 3‐substituted quinoxaline derivatives were synthesized through various synthetic pathways, among which cyanoacetamide and cyanoacetohydrazide quinoxaline derivatives 4a‐c and 11a‐c , respectively, were synthesized. Furthermore, methoxy quinoxaline derivatives 3c and quinoxaline derivatives bearing substituted pyridines 6a,b , 12a,b , and 13a,b were designed to be synthesized. However, we have synthesized acrylohydrazide 5a,b and 7 /acrylamide derivatives, Schiff base analogues 14a‐f , pyrazole derivatives 15a‐e, amide derivatives 16a‐f , guanidine derivatives 16 g,h as well as, quinoxalin‐2‐methylallyl propionate derivative 14g . All the synthesized compounds were confirmed via spectral data and elemental analyses. Moreover, the newly synthesized compounds were evaluated for their antimicrobial activity (Gm +ve, Gm ?ve in comparison to Gentamycin a standard) and fungi (in comparison to Ketoconazole as a standard). Thus, compound 16b showed promising antimicrobial activity against B. subtilis, P. vulgaris, and S. mutants with values ranging from 20 to 27‐mm zone of inhibition. While compounds 5a , 14e,f, and 16a,c,d,g,h showed potent antimicrobial activity. Moreover, the National Cancer Institute (NCI) selected 20 compounds that were submitted for anticancer screening against 60 types of cancer cell lines. The most active compounds are 5b and 12a where compound 5b containing 2,4‐dichlorophenyl moiety at cyanoacetamide linkage of hydrazine quinoxaline backbone exerted significant growth inhibition activity against Leukemia MOLT‐4, Renal cancer UO‐31, and Breast cancer MCF‐7. In addition, compound 12a having 4,6‐diaminopyridinone side chain at position‐3 of quinoxaline nucleus exhibited remarkable anticancer activity against renal cancer UO‐31.     

Organic synthesis and biological evaluation of novel “3 + 1” mixed ligands of technetium-99m Gabapentin as receptor imaging agents

This work focuses on the “3 + 1” mixed ligands of ^99mTc labeled Gabapentin as α2δ receptor imaging agents in the brain. Gabapentin 1-(aminomethyl)cyclohexanacetic acid as monodentate and two tridentates: tridentate A; 3-(2-imino-thiozolidin-4-one)-quinozoline-4-(3H)-one and tridentate B; N-(4-chlorophenyl)-2-imino-2H-chromene-3-Carbothioamide which were synthesized and characterized by infrared analysis (IR), ¹H nuclear magnetic resonance (NMR), and mass spectrum. ^99mTc-complexes were prepared by the “3 + 1” mixed ligand approach. The labeling conditions were optimized and the complexes was extracted by chloroform and purified by high performance liquid chromatography. ^99mTc-complexs were lipophilic and stable for at least 8–12 h at room temperature. The biodistribution of the ^99mTc-complexes was evaluated in mice. The brain uptake was 4.5% and 3.5% ID/g (percentage of the injected dose per gram) at 5 min, and the retention was 1.5% and 1.7% ID/g at 120 min for ^99mTc-complex A and ^99mTc-complex B, respectively.     

A combination of Sylvester block sum and block matrix Kronecker map for explicit solutions of Sylvester system of matrix equations

In this paper, we consider an explicit solution of system of Sylvester matrix equations of the form A₁V₁ ? E₁V₁F₁ = B₁W₁ and A₂V₂ ? E₂V₂F₂ = B₂W₂ with F₁ and F₂ being arbitrary matrices, where V₁,W₁,V₂ and W₂ are the matrices to be determined. First, the definitions, of the matrix polynomial of block matrix, Sylvester sum, and Kronecker product of block matrices are defined. Some definitions, lemmas, and theorems that are needed to propose our method are stated and proved. Numerical test problems are solved to illustrate the suggested technique.     

Bayoumi Quasi-Differential is different from Fréchet-Differential

We prove that the Quasi Differential of Bayoumi of maps between locally bounded F-spaces may not be Fréchet-Differential and vice versa. So a new concept has been discovered with rich applications (see [1–6]). Our F-spaces here are not necessarily locally convex     

Bolzano’s intermediate-value theorem for quasi-holomorphic maps

We extend Bolzano’s intermediate-value theorem to quasi-holomorphic maps of the space of continuous linear functionals from l _p into the scalar field, (0< p<1). This space is isomorphic to l _∞.