(S)-Curvularin and its 13-, 14-, and 16-membered lactone homologues were synthesized through a uniform strategy in which a Kochi oxidative decarboxylation and ring-closing metathesis reactions constitute the key processes. In the evaluation of the anti-inflammatory effects of the synthesized compounds in assays using cells stably transfected with a human iNOS promoter-luciferase reporter gene construct, the 14- and 16-membered homologues showed a slightly higher inhibitory effect towards iNOS promoter activity than curvularin itself. However, the larger ring homologues also exhibited higher cytotoxicity, manifest in downregulated eNOS promoter activity. In contrast, the di-O-acetyl and 4-chloro derivatives of (S)-curvularin showed higher inhibitory efficiency towards induction of the iNOS promoter and less negative effect on eNOS promoter activity than curvularin.

Alternating copolymerization of fluorinated olefins (CnF2n+ 1)(CH2)mCH=CH2 (1) and carbon monoxide was carried out using cationic Pd(II)-(R,S)-BINAPHOS complexes (2) as catalysts. To obtain polymeric products sufficiently, existence of at least two methylenes in 1 were essential (m [Formula: see text] 2). The products thus obtained formed polyspiroketal (4) rather than polyketone (3), the structures being determined by solid- and solution-state NMR and IR analyses. The water contact angle was 108° for a sample of 4f when it was casted on a glass surface from C6F6 solution.Key words: copolymer, fluoroalkene, carbon monoxide, palladium, contact angle.

The molecular structures of triisopropoxystibane, Sb(O i Pr) 3 , and chlorodiisopropoxystibane, SbCl(O i Pr) 2 , were determined in the solid state by single crystal X-ray diffraction. Sb(O i Pr) 3 forms discrete centrosymmetric dimers in the solid state via Sb ؒ ؒ ؒ O-Sb interactions, leading to pseudo trigonal bipyramidal configurations of the four co-ordinate Sb atoms, while SbCl(O i Pr) 2 forms chains via Sb ؒ ؒ ؒ O-Sb and Sb ؒ ؒ ؒ Cl-Sb bridges, resulting in five-coordinate Sb atoms with pseudo octahedral configurations. Comparison of the solid state structures and the density functional optimized molecular structures of Sb(OMe) 3 , SbCl(OMe) 2 and their dimers revealed a steady increase of the average Sb-O bond lengths with the co-ordination number of Sb, and mutual trans effects of the ligands. Standard enthalpies of dimer formation from density functional calculations are Ϫ23.8 and Ϫ69.7 kJ mol Ϫ1 for [Sb 2 (µ-OMe) 2 (OMe) 4 ] and [Sb 2 Cl 2 (µ-OMe) 2 (OMe) 2 ], respectively, and Ϫ42.7 kJ mol Ϫ1 for [Sb 2 (µ-Cl) 2 (OMe) 4 ]. A natural bond orbital analysis reveals that n(O)-σ*(Sb-O) and n(O)-σ*(Sb-Cl) interactions are the main contributions to the inter-monomer bonding in the O-bridged dimers, of Sb(OMe) 3 and SbCl(OMe) 2 , respectively, while n(Cl)-σ*(Sb-O) plays no significant role in the Cl-bridged dimer of SbCl(OMe) 2 . IR and Raman spectra of Sb(O i Pr) 3 indicated molecular association in the solid and liquid phase, but dissociation into monomers in non-polar solvents.

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