Search

The synthetic approaches to novel families of SCE (E = S',N,O) hybrid pincer-type ligands bearing thophosphoryl, thiophosphoryloxy, and thiophosphorylamino groups in various combinations with thiophosphoryl-, thiocarbamoyl-, and imine- (including that of benzothiazole ring) donating functions have been developed. All of the ligands readily undergo direct cyclometallation (metal = Pd(II), Pt(II)) to afford 5,5- or 5,6-membered pincer complexes. Palladium complexes displayed from high to excellent catalytic performance in the Suzuki cross-coupling reaction of aryl bromides and phenylboronic acid and the higher asymmetry for a complex served as a factor of its higher catalytic activity. [ABSTRACT FROM AUTHOR]

Facile synthetic approaches to a few novel classes of amidophosphates, ω-aminophosphonates, and bisphosphonates having a 3,5-bis(arylidene)piperid-4-one backbone have been elaborated starting from piperid-4-ones functionalized with phosphorus motives followed by aldol-crotonic condensation with a range of (hetero)aromatic aldehydes or via introduction of the corresponding phosphorus function into the preformed NH-3,5-bis(arylidene)piperid-4-ones. Combination of phosphorus-containing moieties possessing inherent bioactivity and cytotoxic 3,5-bis(arylidene)piperid-4-one moiety resulted in the compounds with high antitumor activity towards human carcinoma cell lines Caov3, A549, Scov3, PC3, KB 3-1, and KB 8-5 (IC50 in the range of 1-80 μM). [ABSTRACT FROM AUTHOR]

Application of water as a solvent (without any cosolvent) promotes the aza-Michael reaction of diethyl vinylphosphonate and diphenylvinylphosphine oxide with a wide range of N-nucleophiles. The solubility of the starting phosphorus substrate in water does not play a crucial role in the reaction course, decreasing to some extent the reaction rate. The reaction can be performed either at room temperature or under reflux to afford the corresponding β-aminophosphonates and β-aminophosphine oxides in excellent yields and of high purity via a simple freeze-drying isolation procedure. Application of basic catalysts makes possible the addition of weak nucleophiles such as α-amino acids and their phosphorus analogues; that is, α-aminophosphonic acids. The aqueous aza-Michael reaction allowed us to easily perform double phosphorylation of primary amines including polyamines using a reactant ratio (phosphorus substrate: amine) of 2:1. [ABSTRACT FROM AUTHOR]

Abstract: Addition of diethylphosphite to cyclic α-perfluoalkyl substituted imines in the presence of boron trifluoride etherate as a catalyst presents an efficient route for racemic saturated cyclic α-perfluoroalkyl-α-aminophosphonates. Hydrolysis of latter compounds gives the corresponding α-aminoalkanephosphonic acids existing as the corresponding zwitterions according IR and X-ray data. [Copyright &y& Elsevier]

A convenient one-pot synthesis of N-phosphoryl-2-oxo-1,2-azaphospholanes was developed starting from commercially available or simple-to-prepare phosphorus (III) acid chlorides and 3-bromopropylamine. The compounds readily form complexes with f-elements of ML, ML2, and M2L3 composition including (μ2-peroxo)-bridged uranium complexes, depending on both the ligand and metal nature. [ABSTRACT FROM AUTHOR]

Abstract: Water as a solvent significantly accelerates the addition of various amines to diethyl vinylphosphonate to yield β-aminophosphonates without any catalyst compared to known procedures for such aza-Michael reactions. The products are obtained in quantitative yields and high purity over short reaction times. Using a reactant ratio (vinylphosphonate/amine) of 2:1 resulted in double phosphorylation of primary amines. [Copyright &y& Elsevier]

Abstract: In order to design the agents with improved antitumor activity of 3,5-bis(thienylidene)piperid-4-one type, E,E-N-phosphoryl-3,5-bis(thienylidene)piperid-4-ones 6a-c and E,E-N-ω-phosphorylalkyl-3,5-bis-(thienylidene)piperid-4-ones 7a-c were obtained via the direct phosphorylation of the parent NH-3,5-bis(thienylidene)piperid-4-one and by condensation of preformed N-phosphorylalkyl substituted piperidones with thiophene 2-carbaldehyde, respectively. The structures of the compounds were elucidated by 1H, 31P, 13C NMR along with a single crystal X-ray diffraction analysis. Under the action of visible light thermodynamically more stable E,E-isomers slowly undergo photochemical conversion in CDCl3 solution to the corresponding E,Z-isomers and E,Z-N-methyl-3,5-bis(thienylidene)piperid-4-one 5 was isolated in individual state. The importance of phosphorylation for cytotoxic properties of 3,5-bis(thienylidene)piperid-4-ones towards human carcinoma cell lines Caov3, Scov3, and A549 and influence of olefin configuration on antitumor activity were demonstrated. [Copyright &y& Elsevier]

Abstract: A convenient method for the preparation of α-CF3-α-aminophosphonates bearing alkynyl group at the α-carbon atom has been described. New alkynylphosphonates have been further utilized in the synthesis of functionalized triazole-containing α-CF3-α-aminophosphonates via copper-catalyzed (3+2)-cycloaddition to different organic azides. [Copyright &y& Elsevier]

Introduction of oxaphosphorinane moieties into the backbone of the title piperidones results in compounds possessing high antitumor properties toward human carcinoma cell lines. [ABSTRACT FROM AUTHOR]