Synthesis of a Transient Cationic Phosphaborene and its Trapping by Facile Aliphatic C-H Bond Activation.

The synthesis of a transient cationic phosphaborene [(Mes*)P=B(CAAC)]+ (Mes* = 2,4,6,-trit-tert-butylphenyl, CAAC = cyclic alkylamino carbene) by halide abstraction from the B-brominated analogue is reported. This species was found to undergo rapid and selective intramolecular aliphatic C-H bond activation to yield a phosphinoborenium cation, which undergoes facile deprotonation to give a cyclic base-stabilized phosphaborene. Computational investigation of the mechanism of C-H activation indicates a boron-centred activation route with an exceptionally low barrier of 8 kJ mol-1, followed by a nearly barrierless hydride migration from boron to phosphorus.

Highly oxygenated cyclohexenes from the leaves of Roxb. ex Hornem and their cytotoxic and -glucosidase inhibitory activities.

Phytochemical investigation of the leaf extract of Roxb. ex Hornem led to the isolation and identification of two new highly oxygenated cyclohexenes, uvariagrandols A () and B (), together with seven known compounds (-). Their structures were elucidated by spectroscopic methods as well as comparisons made from the literature.

Nigrosporinol Sulfoxides A and B, Sulfur-Bridged Heterocyclic Sesquiterpenoids Produced by Cultures of the Fungus .

The sesquiterpenoids nigrosporinol sulfoxides A () and B () have been isolated from cultures of the endophytic fungus harvested from the sunchoke L. collected in Thailand. Nigrosporinol sulfoxides A () and B () have 4/5/5/5/7 heterocyclic skeletons featuring a sulfoxide bridge not previously found in a terpenoid natural product from any living source.

Alkaloids and Styryl Lactones from and Their Biological Activities.

Phytochemical investigations of the twig and leaf extracts of resulted in the isolation and identification of two new alkaloids, goniotortiline () and goniotortilactam (), three new styryl lactone derivatives, goniotortilactone () and goniotortilols A () and B (), and 25 known compounds. Their structures were elucidated by spectroscopic methods and HRESITOFMS data. Compounds , , , , , and inhibited nitric oxide (NO) production with IC values ranging from 8.

Alkyl initiated ring opening polymerization of lactide by indium complexes supported by NCN pincer ligands.

Indium-alkyl NCN pincer complexes supported by amine and imine donors are active catalysts for the ring opening polymerization of lactide. The amine indium complexes are significantly more active for polymerization due to the decoordination of the amine donors at higher temperatures. Solid state structures of the imine and amine indium complexes indicate that the imine-indium bonds are stronger than the analogous amine-indium bonds.