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In biology-oriented synthesis the underlying scaffold classes of natural products selected in evolution are used to define biologically relevant starting points in chemical structure space for the synthesis of compound collections with focused structural diversity. Here we describe a highly enantioselective synthesis of natural-product-inspired 3,3′-pyrrolidinyl spirooxindoles—which contain an all-carbon quaternary centre and three tertiary stereocentres. This synthesis takes place by means of an asymmetric Lewis acid-catalysed 1,3-dipolar cycloaddition of an azomethine ylide to a substituted 3-methylene-2-oxindole using 1–3 mol% of a chiral catalyst formed from a N,P-ferrocenyl ligand and CuPF6(CH3CN)4. Cellular evaluation has identified a molecule that arrests mitosis, induces multiple microtubule organizing centres and multipolar spindles, causes chromosome congression defects during mitosis and inhibits tubulin regrowth in cells. Our findings support the concept that compound collections based on natural-product-inspired scaffolds constructed with complex stereochemistry will be a rich source of compounds with diverse bioactivity. [ABSTRACT FROM AUTHOR]

In the title compound, C40H32N2O2P2, used as a nixantphos-type ligand in homogeneous catalysis, the central phenoxazine ring system deviates markedly from planarity, the dihedral angle between the two halves being 38.14 (3)°. The intra­molecular P⋯P distance is 4.2400 (7) Å. [ABSTRACT FROM AUTHOR]

The title compound, C21H26N2, a potential chiral ligand for transition metal-catalysed reactions, crystallizes with one mol­ecule in the asymmetric unit; the mol­ecule has a pseudo-twofold axis perpendicular to the central C=C=C fragment. [ABSTRACT FROM AUTHOR]

The bismuth halides BiX3 (X=Cl, Br, I) react with the chelating oxygen-coordinating-donor ligand (iso-PrO)2(O)PCH2P(O)(Oiso-Pr)2 (L) to give one-to-one complexes, which have been characterised by single crystal X-ray-diffraction, IR spectroscopy, thermal analysis, NMR-spectroscopy, electrospray ionisation mass spectrometry (ESI MS) and conductivity measurements. In the solid state the complexes [BiX3L]2 (1, X=Cl; 2, X=Br; 3, X=I) show a dimeric bi-octahedral structure. Thermolysis analyses show that amorphous bismuth phosphonates are formed when the bulk material is heated to temperatures in the range 160–180 °C. The liberation of iso-PrX (X=Cl, Br, I) and propene is observed in this temperature range. The solid state structures are not retained in solution and electrospray ionisation mass spectrometry of CH3CN solutions of 1–3 revealed the presence of compounds such as [(iso-PrO)2(O)PCH2P(O)(Oiso-Pr)2H]+, [BiX2L2]+ and [BiX4]− (X=Cl, Br, I). [Copyright &y& Elsevier]

In the title compound, C40H33NO3P2, used as a nixantphos-type ligand in homogeneous catalysis, the central phenoxazine ring system is nearly planar. The most important feature of the mol­ecule is the intra­molecular P⋯P distance of 4.2346 (13) Å. The angles involving the P atoms are in the range 100.90 (13)–103.40 (16)°. [ABSTRACT FROM AUTHOR]

The title compound, C42H41NOP2Si, used as a nixantphos-type ligand in homogeneous catalysis, crystallizes with one mol­ecule in the asymmetric unit. The mol­ecule has nearly mirror symmetry with N, O and Si on the pseudo-mirror plane, but it is not located on a crystallographic mirror plane. The most important feature of the mol­ecule is the intra­molecular P—P distance of 4.1453 (12) Å. The bond angles involving the P atoms are in the range 100.32 (14)–103.04 (15)°. [ABSTRACT FROM AUTHOR]