We present gas-phase infrared spectra of tantalum cluster cations containing 6-20 atoms. Infrared multiple photon dissociation of their complexes with argon atoms is used to obtain vibrational spectra in the region between 90 and 305 cm(-1). Many spectra have features in common with the vibrational spectra of the lighter homologs, vanadium and niobium, pointing to a common cluster growth mechan...

Vanadium complexes have been used extensively to catalyze olefin and alcohol oxidation. However, their application in C-H oxidation has not been well-studied. We report herein that commercially available Cp(2)VCl(2) catalyzes benzylic C-H oxidation selectively and effectively, giving no aromatic oxidation products.

The geometry of cationic silicon clusters doped with vanadium, Si(n)V(+) (n=12-16), is investigated by using infrared multiple photon dissociation of the corresponding rare gas complexes in combination with ab initio calculations. It is shown that the clusters are endohedral cages, and evidence is provided that Si(16)V(+) is a fluxional system with a symmetric Frank-Kasper geometry.

Soft landing (SL) of mass-selected ions is used to transfer catalytically-active metal complexes complete with organic ligands from the gas phase onto an inert surface. This is part of an effort to prepare materials with defined active sites and thus achieve molecular design of surfaces in a highly controlled way. Solution-phase electrochemical studies have shown that V(IV)O(salen) reacts in th...

Vanadium complexes have been previously utilised as potent inhibitors of cysteine based phosphatases (CBPs). Herein, we present the synthesis and characterisation of two new fluorescently labelled vanadyl complexes (14 and 15) with bridged di-picolinic acid ligands. These compounds differ significantly from previous vanadyl complexes with phosphatase inhibition properties in that the metal-chel...

the reaction of bis[4-hydroxy-3-methoxyphenyl]-1,6-heptadiene-3,5-dione (curcumin) and two novel ligands of bis[4-tetrabenzylglucose-3-methoxyphenyl]-1,6-heptadiene-3,5-dione (bis(tetrabenzylglucose)curcumin) (btbgc) and bis[4-tetraacetylglucose-3-methoxyphenyl]-1,6-heptadiene-3,5-dione (bis(tetraacetylglucose)curcumin) (btagc) with vanadium in methanol, in a 2:1 molar ratio, which yield the co...

An alkylating camptothecin (CPT) derivative, 7-chloromethyl-10,11-methylenedioxy-camptothecin (7-CM-MDO-CPT) was recently shown to produce irreversible topoisomerase I (top1) cleavage complexes by binding to the +1 base of the scissile strand of a top1 cleavage site. We demonstrate that 7-CM-EDO-CPT (7-chloromethyl-10,11-ethylenedioxy-camptothecin) also induces irreversible top1-DNA complexes. ...