Microwave promoted synthesis and anticological screening of <Emphasis Type="Italic">β</Emphasis>-aminobisphosphonates-based benzothiazole motif against human breast and colon cancer diseases

New antineoplastic series of substituted benzothiazolo-β-aminobisphosphonic acids have been developed on the basis of the prospecting potency of the benzothiazole motifs and the aminomethylenebisphosphonate moiety as well as on the prediction of the biological activity utilizing computer program PASS, version 2014-1. Target compounds were obtained in excellent yields (70–90%) via Phospha–Michael-type addition reaction of tetraethyl methylene-1,1-bisphosphonate reagent to a group of Schiff bases incorporating benzothiazole moiety. The reactions proceeded under microwave irradiation, utilizing the advantages of the environment, friendly protocol such as high efficiency, short reaction time, and excellent yields. In consistency with the prospected results, the new NBP acids revealed positive properties against human breast and colon tumor cell lines. Remarkable potency for six lead compounds (out of 12) was observed against breast (MCF7, MDAMB/435, MDAMB/231/ATCC, HS-578T with GI₅₀: 2.05–6.47 μM) and colon (COLO-205, HCT-116, HCC-2998, and SW-620 with GI₅₀: 3.03–7.92 μM) carcinoma cell lines when compared with the positive control Adriamycin (breast, GI₅₀: 3.27–6.64 μM; colon, GI₅₀: 4.09–8.75 μM). Notably, there is a consistency between the prediction and the determined biological results.     

Crystal structure of (S,S)-diphenylethanediammonium (R,R)-tartrate

Summary The crystal structure of (–)-diphenylethanediammonium-(R,R)-tartrate was determined. From this structure determination, the (S,S) configuration was assigned to the (–)-diphenylethanediamine. The asymmetric unit of the crystal structure contains two units of the title compound plus one molecule of ethanol and one water molecule, which form an intricate network of 19 hydrogen bonds.

---

Die Kristallstruktur von (S,S)-Diphenylethandiammonium-(R,R)-tartrat

Zusammenfassung Es wurde die Kristallstruktur von (–)-Diphenylethandiammonium-(R,R)-tartrat bestimmt. Aus dieser Strukturbestimmung ergab sich die Zuordnung der (S,S)-Konfiguration zum (–)-Diphenylethandiamin. Die asymmetrische Einheit der Kristallstruktur besteht aus zwei Formeleinheiten der Titelverbindung sowie einem Molekül Ethanol und einem Wassermolekül, welche ein komplexes Netzwerk von insgesamt 19 Wasserstoffbrücken bilden.

     

Heterocycles from Pyrazoloylhydroximoyl Chloride: Synthesis of Certain Quinoxaline,Benzothiadiazine, Benzoxadiazine,Quinazolinone, Imidazo[1,2-a]pyridine,Imidazo[1,2-a]pyrimidine,Isoxazole, Pyrazolo[3,4-d]pyridazine and Pyrrolidino[3,4-d]isoxazolin-4,6-dione Derivatives

3-Ethoxycarbonyl-5-methyl-1-(4-methylphenyl)-4-pyrazoloylhydroximoyl chloride (1) reacted with o-phenylenediamine, o-aminothiophenol, o-aminophenol and methyl anthranilate to afford 3-nitrosoquinoxaline, benzothiadiazine, benzoxadiazine, and 3-hydroxyquinazoline, respectively. Imidazo[1,2-a]pyridine, imidazo[1,2-a]pyrimidine and isoxazole derivatives were obtained via the reaction of 1 with 2-aminopyridine, 2-aminopyrimidine and the appropriate active methylene compounds, respectively. Pyrazolo[3,4-d]pyridazines, and pyrrolidino[3,4-d]isoxazolines derivatives were also synthesized. The structures of the newly synthesized compounds were established on the basis of spectral data and alternate synthesis whenever possible.     

AVNb3Cl11 (A = K, Rb, Cs, Tl): a series of layered vanadium niobium halides based on triangular Nb3 clusters

The first quaternary vanadium niobium compounds containing triangular Nb(3) clusters corresponding to the general formula, AVNb(3)Cl(11) (A = K, Rb, Cs, Tl), have been prepared in sealed quartz tubes from stoichiometric amounts of ACl (A = K, Rb, Cs), or Tl metal, VCl(3), Nb powder, and NbCl(5) heated at 740 degrees C. The compounds crystallize in the orthorhombic space group Pnma (No. 62). The crystal structures of the Rb and Tl members were determined by single-crystal X-ray diffraction techniques. Crystal data: a = 12.771(3) A, b = 6.811(2) A, c = 17.183(3) A, V = 1494.6(1) A(3), and Z = 4 for A = Rb; and a = 12.698(5) A, b = 6.798(3) A, c = 17.145(10) A, V = 1480.0(13) A(3), and Z = 4 for A = Tl. The crystal structure of AVNb(3)Cl(11) consists of triangular Nb(3)Cl(13) clusters (Nb-Nb = 2.826 A) connected to each other via four outer ligands to form infinite chains along the b-axis. The chains are connected by vanadium atoms located in an octahedral environment to form puckered sheets. The A(+) counterions are located between adjacent sheets and coordinate to twelve chlorine ligands in anticubeoctahedral geometry. Electronic structure calculations show bonding orbitals similar to those in Nb(3)Cl(8). Magnetic susceptibility measurements show paramagnetic Curie Weiss behavior.     

Crystal structure of KSbP2O8

KSbP₂O₈ crystallizes in the rhombohedral system, space group $\text{R}\text{3}$, with a = 4.7623(4) Å, c = 25.409(4)Å, and Z = 3. The structure was determined from 487 reflexions collected on a NONIUS CAD4 automatic diffractometer with MoK^?α radiation. The final R index and weighted R_w index are 0.030 and 0.038, respectively. This structure is built up from layers of SbO₆ octahedra and PO₄ tetrahedra sharing corners. These (SbP₂O^?₈)_n layers are very similar to the (ZrP₂O^2?₈)_n layers in the well-known α-ZrP compound.     

Reactions with Naphthoylhydroxlmoyl Chlorides: Synthesis of Derivatives of Isoxazole,Pyrrolidino[3,4-d]isoxazoiin-4,6-dione,lmidazo[1,2-a]pyridine,lmidazo[1,2-a]pyrimidine,Benzotriazine and Benzothiadiazine

Hydroximoyl chlorides 3 react with acrylonitrile, N-arylmaleimide and maleic anhydride to give isoxazolines 5 , pyrrolidino[3,4-d]isoxazolines 8 , and furolidino[3,4-d]isoxazolines 9 , respectively. 3 reacted with 2-aminopyridine, 2-aminopyrimidine, o-phenylenediamine and o-aminothiophenol to yield 3-ni-trosoimidazo[1,2-α]pyridines 20 , 3-nitrosopyrimidines 22 , 3-naphthoyl-1,4-dihydrobenzo-1,2,4-triazines 24 , and 3-naphthoyl-4H-1,3,4-benzothiadiazine 27 , respectively. Compound 3 reacted with benzoylacetonitrile, acetoacetanilide, thiophenol, benzencsulfinic acid in ethanolic sodium ethoxide solution to give the corresponding isoxazoles 12–13 and oximes 16–17 , respectively. The structures of these products were confirmed by elemental analyses, spectral data and, wherever possible, alternative synthesis.     

Crystallographic,spectroscopic and electrochemical characterization of pyridine adducts of magnesium(II) and zinc(II) porphine complexes

A new purification method of magnesium(II) and zinc(II) porphine complexes (MgP and ZnP, respectively) by crystallization of their respective pyridine adducts is described. Pure MgP and ZnP can be regenerated by removal of the coordinated pyridine ligands by heating at 200 °C under vacuum. X-ray crystallographic structures of the pyridine adducts are presented for the first time. NMR analyses of the adducts reveal the coordination of two pyridine molecules. Electrochemical as well as UV-vis absorption spectroscopy analyses in DMF of MgP·(Py)₂, ZnP·(Py)₂, MgP and ZnP indicate that pyridine adducts are totally dissociated. Besides, oxidation peaks of these complexes are totally irreversible, revealing a high reactivity of the oxidized species. Electrolyses at the first oxidation potential lead to the formation of the meso-meso (ZnP)₂ and (MgP)₂ dimers, oligomers and polymers on the electrode surface, as attested by MALDI-TOF mass spectrometry and UV-vis absorption spectroscopy analyses of the crude solution.     

General Approach for Regioselective Synthesis of Fused Phosphono Substituted-Heterocycles. Reactions of Bismethylene-1,3-dithietane with H -Nucleophiles

A number of [2,1- b ] fused phosphono substituted-thioxopyranes, -oxadiazines, and -thiazines were obtained from the reactions of the corresponding f -carbonyl methylenes and f -carbonylmonohydrazones with phosphenato-substituted 1,3dithietane 1 .     

PHOTOCHEMISTRY OF PESTICIDES, 13.1 SOME PHOTOREACTIONS OF O,O-DIETHYL-O-(4-METHYL-2-OXO-2H-1-BENZOPYRAN-7-YL)-PHOSPHOROTHIOATE (POTASAN®)

Abstract

UV-irradiation (δ > 313nm) of O,O-diethyl-O-(4-methyl-2-oxo-2H-1-benzopyran-7-yl)-phosphoro-thioate (Potasan®) la in chloroform and/or methanol with and without singlet oxygen results in the formation of the 2-oxo-2H-1-benzopyran-phosphate 2 the 3,3′-bipotasan dehydrodimer 3, and 7-ethoxy-4-methyl-2-oxo-2H-1-benzopyran 4: the mechanisms of formation, especially for 4 are discussed.     

An improved variational iteration method for solving coupled KdV and Boussinesq-like B(m, n) equations

In this article, we implement a new analytical technique; He’s variational iteration method for solving the coupled KdV and Boussinesq-like equations. In this method, first general Lagrange multipliers are introduced to construct correction functional for the problems. The multipliers in the functional can be identified optimally via the variational theory. Next the components of obtained iteration formulae defined by partial sum of other sequence, specially constructed according to Adomian’s decomposition method (ADM). Also according to ADM we used a partial sum of Adomian polynomials instead of nonlinear terms in iteration formulae. The initial approximations can be freely chosen with possible unknown constants, which can be determined by imposing the initial conditions. The results reveal that the proposed method is very effective and can be applied for other nonlinear problems.