A series of new pentadentate thioether-oximes (TtoxH2, MeTtoxH2, OdtoxH2) were synthesized along with their Ni(II) and Cu(II) complexes. BF2 -bridging is accomplished by reaction of the H-bonded oxime complex with BF3·OEt2, though when Cu(BF4)2 is used as the Cu(II) salt, direct macrocyclization occurs during the metal complexation reaction. Crystallographic studies reveal: [Cu(TtoxH)]ClO4 has ...

The potent calcium channel blocker ω-conotoxin MVIIA is a linear cystine-knot peptide with multiple basic amino acids at both termini. This work shows that macrocyclization of MVIIA linking two positive-charge terminal clusters as a contiguous segment converts a conotoxin into an antimicrobial peptide. In addition, conversion of disulfide bonds to amino butyric acids improved the antimicrobial ...

The key building block of our flexible approach to the modular synthesis substituted cycloparaphenylenes (CPPs) is in spotlight. From this stage, depicted [8]- and [10]CPPs were synthesised two more steps, macrocyclization reductive aromatization. optoelectronic properties these nanorings compared those parent CPPs, as well tube-like solid state structure. More information can be found Research...

Two conceptually different and novel radical-mediated cascade reactions leading to a total synthesis of the steroid (+/-)-estrone 1 and to a synthesis of 14-epiestrone 40 are described. Treatment of the iododienynone 23 with Bu(3)SnH/2,2'-azobis(isobutyronitrile) (AIBN) triggers a 13-endo-dig radical macrocyclization followed by two sequential radical transannulation reactions leading to the cr...

Collision-induced dissociation of protonated AGabaAIG (where Gaba is gamma-amino butyric acid, NH(2)-(CH(2))(3)-COOH) leads to an unusually stable a(3) ion. Tandem mass spectrometry and theory are used here to probe the enhanced stability of this fragment, whose counterpart is not usually observed in CID of protonated peptides containing only alpha amino acids. Experiments are carried out on th...