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A readily available and air-stable ferrocenyldiethylphosphine that is a highly active catalyst in the Baylis-Hillman reaction between acrylates and aldehydes is described. Enantioselectivities up to 65% cc are obtained in the asymmetric Baylis-Hillman reaction using planar chiral ferrocenylphosphines.

The thermal oxidative cyclization of [beta]-arylaminoporphyrins were used to synthesize N-arylquinolino[2,3,4-at]porphyrins. The reactions resulted in formation of the corresponding 2-arylaminoporphyrin derivatives and N-arylquinolino[2,3,4-at]porphyrins.

A study was conducted to explore the antioxidant and redox properties of four novel 3-alkylpolyhydroxyflavones (FnH) mimicking the microenvironment relevant to antioxidant activity in biological structures. The experimental results for biological systems such as blood lipoproteins and cultured cells demonstrated the activities of FnH with n>4 as much better inhibitors of lipid peroxidation and of cell injury than quercetin, the most effective natural flavonoid antioxidant.

Porphyrins were used in 1,3-dipolar cycloaddition reactions simultaneously as dipoles and as dipolarophiles. New porphyrin-chlorin and porphyrin-tetraazachlorin dyads were obtained from those reactions.

Electrospray ionization mass spectrometry (ESI-MS) and tandem mass spectrometry (ESI-MS/MS) have been used to differentiate the 2- and 4-methylpyridyl isomers of free-base and metallated cationic β-vinylpyridylporphyrins. The analysis by ESI-MS/MS of the deuterated analogs and semiempirical calculations of structural and electronic parameters were also undertaken. The two free-base isomers are easily differentiated by ESI-MS/MS but the presence of a metallic center renders differentiation of the metallated isomers less effective. The data acquired show that of all the studied compounds, the free-base 2-methylpyridyl isomer, which was operative in the in vitro photoinactivation of Herpes simples virus, has a different gas-phase behavior. Local distortion of the macrocycle due to the presence of the β-vinylpyridyl substituent occurs for all the compounds, but a different electron density distribution can account for the observed gas-phase behavior of this potential virus photoinactivator. [Copyright &y& Elsevier]