L-cysteine-induced fabrication of spherical titania nanoparticles within poly(ether-imide) matrix.

In the presented study, a new L-cysteine-containing diamine is synthesized and fully characterized and its application for the in situ sol-gel fabrication of poly(ether-imide)/titania nano hybrid materials is investigated. The electron microscopic photographs (TEM, FE-SEM and AFM) of the resulted materials confirm the production of spherical nanoparticles with well dispersion and narrow particle size distribution which is a usual challenge in the sol-gel methods. In addition to the positive effects on the particles morphology, the existence of amino acid containing pendant groups in the structure of polymer chains led to the comprehensive interaction with titania phase. As a result, the improvement in the flexibility of polymer backbone (as one of the most serious difficulties in polyimides processing) is obtained while its thermal stability dose is not sacrificed (confirmed by TGA and DSC techniques).

Synthesis and characterization of new Pd(II) complexes of L-ethylphenylalanate.

Complex (S,S)-[Pd{C(6)H(4)(CH(2)CHNH(2)CO(2)CH(2)CH(3))}(mu-Br)](2) (3) was prepared following the method by Vicente and Saura-Llamas (Organometallics 26:2768-2776, 2007), by the reaction of L: -ethylphenylalanate and Pd(OAc)(2) in 1:1 molar ratio under acetonitrile heating conditions and subsequently treating with NaBr. In addition, the cleavage of halogeno-bridge of the complex 3 via nucleophilic attack of some neutral ligands such as triphenylphosphine, pyridine, 2,4,6-trimethylpyridine and piperidine were investigated and the corresponding complexes (S)-[Pd{C(6)H(4)(CH(2)CHNH(2)CO(2)CH(2)CH(3))(Y)(Br)}] (4a-f) were obtained in moderate yields. The six-member orthopalladated complexes were characterized by (1)H-NMR, (31)P-NMR, FT-IR and elemental analysis techniques.

Synthesis and Evaluation of a 64Cu-Conjugate, a Selective δ-Opioid Receptor Positron Emission Tomography Imaging Agent.

Given the putative selectivity of the antagonist TIPP (Tyr-Tic-Phe-Phe) for δ-opioid receptors (DOP), this compound was selected for the design of a novel 64Cu-radiolabeled potent and selective DOP positron emission tomography (PET) imaging agent. Ex vivo autoradiography of TIPPD-PEG-K(NOTA/64Cu)-NH2 on rat brain sections produced a distribution pattern consistent with the known expression of DOP. Taken together, the in vitro and ex vivo data indicate that this 64Cu-tracer holds promise for studying the DOP by means of PET.