Ulrich Abram

Bio: Ulrich Abram is an academic researcher from Dresden University of Technology. The author has contributed to research in topics: Electron paramagnetic resonance & Rhenium. The author has an hindex of 25, co-authored 146 publications receiving 3841 citations.

Stable one-step technetium-99m labeling of His-tagged recombinant proteins with a novel Tc(I)-carbonyl complex.

Abstract: Stable one-step technetium-99m labeling of His-tagged recombinant proteins with a novel Tc(I)–carbonyl complex

Synthesis and reactivity of [NEt4]2[ReBr3(CO)3]. Formation and structural characterization of the clusters [NEt4][Re3(µ3-OH)(µ-OH)3(CO)9] and [NEt4][Re2(µ-OH)3(CO)6] by alkaline titration

Abstract: The dianionic rhenium(I) complex [ReBr3(CO)3]2– has been synthesized and characterized. This complex is an important starting material for compounds containing the fac-Re(CO)3 moiety since the three bromide ligands are very weakly bound. Particularly in co-ordinating solvents, the bromides are substituted by solvent molecules thus generating the strong 12e– Lewis acid [Re(H2O)3(CO)3]+2. This formula was confirmed, particularly in water, by IR spectroscopic methods. Complex 2 is stable in aqueous solution even when exposed to air for weeks. It has been titrated by NaOH solutions. The change in pH was detected potentiometrically and found to occur very slowly, indicating a reaction other than protonation deprotonation. Depending on the rate of titration and the total concentration of OH–, the two rhenium(I) hydroxo complexes [NEt4][Re3(µ3-OH)(µ-OH)3(CO)9] and [NEt4][Re2(µ-OH)3(CO)6] were isolated in good yield and structurally characterized. The former crystallizes in the orthorhombic space group Pnma with a= 10.752(7), b= 13.783(8) and c= 18.254(12)A. The skeletal framework is that of a cube lacking the Re(CO)3 unit in one corner. The latter crystallizes in the orthorhombic space group P2mm with Z= 1, a= 6.551(2), b= 7.413(2) and c= 12.084(2)A. The two Re(CO)3 moieties are bridged by three OH– ligands which create a mirror plane. A second mirror plane is perpendicular to it along the Re-Re axis.

Secondary building units, nets and bonding in the chemistry of metal–organic frameworks

Abstract: This critical review presents a comprehensive study of transition-metal carboxylate clusters which may serve as secondary building units (SBUs) towards construction and synthesis of metal–organic frameworks (MOFs). We describe the geometries of 131 SBUs, their connectivity and composition. This contribution presents a comprehensive list of the wide variety of transition-metal carboxylate clusters which may serve as secondary building units (SBUs) in the construction and synthesis of metal–organic frameworks. The SBUs discussed here were obtained from a search of molecules and extended structures archived in the Cambridge Structure Database (CSD, version 5.28, January 2007) which included only crystals containing metal carboxylate linkages (241 references).

Arming antibodies: prospects and challenges for immunoconjugates

Abstract: Immunoconjugates--monoclonal antibodies (mAbs) coupled to highly toxic agents, including radioisotopes and toxic drugs (ineffective when administered systemically alone)--are becoming a significant component of anticancer treatments. By combining the exquisite targeting specificity of mAbs with the enhanced tumor-killing power of toxic effector molecules, immunoconjugates permit sensitive discrimination between target and normal tissue, resulting in fewer toxic side effects than most conventional chemotherapeutic drugs. Two radioimmunoconjugates, ibritumomab tiuxetan (Zevalin) and tositumomab-131I (Bexxar), and one drug conjugate, gemtuzumab ozogamicin (Mylotarg), are now on the market. For the next generation of immunoconjugates, advances in protein engineering will permit greater control of mAb targeting, clearance and pharmacokinetics, resulting in significantly improved delivery to tumors of radioisotopes and potent anticancer drugs. Pre-targeting strategies, which separate the two functions of antibody-based localization and delivery or generation of the toxic agent into two steps, also promise to afford superior tumor targeting and therapeutic efficacy. Several challenges in optimizing immunoconjugates remain, however, including poor intratumoral mAb uptake, normal tissue conjugate exposure and issues surrounding drug potency and conditional release from mAb carriers. Nonetheless, highly promising results from preclinical models will continue to drive the clinical development of this therapeutic class.

Is this a practical approach

Abstract: 1. Health care is a human right. 2. The care of the individual is at the center of health care, but the whole system needs to work to improve the health of populations. 3. The health care system must treat illness, alleviate suffering and disability, and promote health. 4. Cooperation with each other, those served, and those in other sectors is essential for all who work in health care. 5. All who provide health care must work to improve it. 6. Do no harm.

Click Chemistry, A Powerful Tool for Pharmaceutical Sciences

Abstract: Click chemistry refers to a group of reactions that are fast, simple to use, easy to purify, versatile, regiospecific, and give high product yields. While there are a number of reactions that fulfill the criteria, the Huisgen 1,3-dipolar cycloaddition of azides and terminal alkynes has emerged as the frontrunner. It has found applications in a wide variety of research areas, including materials sciences, polymer chemistry, and pharmaceutical sciences. In this manuscript, important aspects of the Huisgen cycloaddition will be reviewed, along with some of its many pharmaceutical applications. Bioconjugation, nanoparticle surface modification, and pharmaceutical-related polymer chemistry will all be covered. Limitations of the reaction will also be discussed.