An Aromatic Proton Transfer to the o-Amine Function: Naphthoquinonyne Intermediate and Cycloaddition Reactions.

The article reports a hitherto-unknown aromatic proton transfer (APT) to the o-amine function chelated to manganese(II) ion and disintegration of the molecule generating an aryne intermediate. The reaction of (NQ)-NH(AQ) (o-HLH) with manganese(II) acetate in boiling DMF generates [MnII(o-HL-)2], where the o-HLH ligands undergo disintegration forming manganese(II) complexes of AQ and an 1,4- naphthoquinonyne intermediate based on benzoquinone ring, that has been defined as [NQ-2H] (NQ and AQ abbreviate respectively 1,4-naphthoquinone and 8-aminoquinoline fragments). The disintegration reaction of o-HLH depends on the metal precursor used, solvent and temperature.

Epidermal growth factor receptor and proliferating cell nuclear antigen in astrocytomas.

Aims: The involvement of various growth factors, growth factor receptors and proliferative markers in the molecular pathogenesis of astrocytic neoplasms are being studied extensively. Epidermal Growth Factor Receptor (EGFR) gene overexpression occurs in nearly 50% of cases of glioblastoma. Since EGFR and proliferating cell nuclear antigen (PCNA) are involved in mitogenic signal transduction and cellular proliferation pathway, we have studied the correlation between the expression of EGFR and PCNA labeling index in astrocytic tumors.

New Pd-catalyzed selective reduction of carboxylic acids to aldehydes.

A catalyst generated in situ from palladium acetate and tricyclohexylphosphine efficiently catalyzes the reduction of carboxylic acids with sodium hypophosphite in the presence of pivalic anhydride to give aldehydes with high selectivity. The low cost and convenient handling of the reagents makes this process a valuable alternative to hydrogenations and metal hydride reductions.