The enantioselective catalytic hydrogenation of N-(3,4-dihydronaphthalen-2-yl) amides (1) with rhodium catalysts bearing phosphine-phosphite ligands 4 has been studied. A wide catalyst screening, facilitated by the modular structure of 4, has found a highly enantioselective catalyst for this reaction. This catalyst gives a 93% ee in the hydrogenation of 1a and also produces high enantioselectiv...

A furanoside phosphite-phosphoroamidite and diphosphoroamidite ligand library L1-L5a-f was tested in the asymmetric Rh-catalyzed hydrogenation of α,β-unsaturated carboxylic acid derivatives and enamides. Enantioselectivity depended strongly on the ligand parameters. High enantioselectivities were obtained in the reduction of dimethyl itaconate (up to >99% ee), α-dehydroamino acid esters (up to ...

Solid phase synthesis of phosphonate-modified oligoribonucleotides using 2'-O-benzoyloxymethoxymethyl protected monomers is presented in both 3'→5' and 5'→3' directions. Hybridisation properties and enzymatic stability of oligoribonucleotides modified by regioisomeric 3'- and 5'-phosphonate linkages are evaluated. The introduction of the 5'-phosphonate units resulted in moderate destabilisation...

A cationic, pentanuclear aluminium phosphonate cage, [L(4)Al(5)Cl(6)(THF)(6)]Cl, 1, supported by (phthalimidomethyl) phosphonate, (L), has been synthesized and characterized. This polynuclear cage features the phosphonate ligand in an unusual coordination mode, supporting five aluminium atoms in two different environments. In comparison, the aqueous reaction of LH(2) with In(ClO(4))(3) afforded...

Considerable attention has been focused on the development of phosphonate-containing drugs for application in many therapeutic areas. However phosphonate diacids are deprotonated at physiological pH and thus phosphonate-containing drugs are not ideal for oral administration, an extremely desirable requisite for the treatment of chronic diseases. To overcome this limitation several prodrug struc...

Phosphonates, molecules containing direct carbon-phosphorus bonds, compose a structurally diverse class of natural products with interesting and useful biological properties. Although their synthesis in protozoa was discovered more than 50 y ago, the extent and diversity of phosphonate production in nature remains poorly characterized. The rearrangement of phosphoenolpyruvate (PEP) to phosphono...

This study was conducted to investigate the biodegradation potential of neutralized organophosphorus nerve agents: O-ethyl-S-(2-diisopropyl-aminoethyl) methylphosphonothioate (VX), Sarin (GB), Soman (GD), and O-cyclohexyl methylphosphonofluoridate (GF). Removing labile leaving groups from these compounds can be accomplished chemically (e.g. alkali) or enzymatically (by a variety of hydrolases) ...