Strategies replacement

Most tritium-labeled compounds are prepared by one of several hydrogen/tritium replacement processes. This is made possible by the facihty with which carbon-hydrogen bonds can be broken and re-formed, by the simphcity of many such reactions, and by the different 

Preparation of Compounds Labeled with Tritium and Carbon-14 Rolf Voges, J. Richard Heys and Thomas Moenius 2009 John Wiley Sons, Ltd. ISBN 978-0-470-51607-2 

Two-Step Oxidation—Reduction Strategies of Hydroxyl Functions 

A -hydroxysuccinimide ester, followed by NaB H reduction and cleavage of the protecting groups, provided [ H]6 at a specific activity of 14Ci/mmol.  

Reaction conditions 1. RuClj, Nal04, CCI4, HjO 2. /V-hydroxysucdnimide, EDCI, CH2CI2 3. NaBH, THE 4a. TEA, CH2CI2. b. NaOH 

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A similar terminal-peptide-replacement strategy was used in the Src SH2 domain antagonist program pursued at the Parke-Davis Pharmaceutical Re-... 

Scheme 8. Terminal-peptide-replacement strategy pursued by Parke-Davis... 

Scheme 9. Asn-replacement strategy utilizing the (3-amino acid 51...

Treatment of acute opioid withdrawal is largely pharmacological. Most commonly, a replacement strategy is used where the person is switched to a longer-acting, oral opioid such as methadone. 

Roth JA, Grammer SF, Swisher SG, et al. Gene replacement strategies for treating non-small cell lung cancer. Semin Radiat Oncol 2000 10(4) 333-342. 

Lim, D.A., Huang, Y.C., Alvarez-Buylla, A. (2007) The adult neural stem cell niche lessons for future neural cell replacement strategies. Neurosurg Clin N Am 18, 81-92, ix. 

CATS3D was not only successful in scaffold hopping on the basis of the definition above (Meqi). We also observed a substructure hopping , which might be seen as an equivalent to more traditional bioisosteric replacement strategies. It seems that the CATS descriptor family represents molecules in a way that allows a combination of scaffold hopping and substructure hopping at once. This can result in a selection of molecules which would not be considered similar by other methods such as the MACCS keys. 

Progress in insulin replacement strategies utilizing gene therapy... 

Although replacement therapy is classically exemplified by the treatment of hypofunctioning endocrine glands, there is an important neurological disorder that can be successfully treated with a replacement strategy. Parkinson s disease is a clinical syndrome characterized by slowness of movement, muscular rigidity, resting tremor, and an impairment of postural balance. In the absence of therapy, death frequently results from complications of immobility. 

BF3 + NH3 —> BF3NH3. In the ammonia molecule there is a nonbonding pair of electrons that can react in a variety of ways. Later in the book, you will learn about complexes that can form with ammonia. In this reaction, boron trifluoride is a molecule that is usually represented with only 6 electrons around the central boron, making it a perfect mate for the ammonia molecule. As tempted as you might be to try to apply a double-replacement strategy here, remember that they are both molecular substances. This suggests another approach a combination reaction. 

Bioisosteric replacement strategy has been fruitful in design of psychoactive agents, by... 

However, replacement strategies are not straightforward with compromises on either performance and cost having to be addressed. An excellent example of this centres around the chlorine issue. Chlorine imparts a unique set of properties to addition polymers, such as the ability to crystallise on film formation. Vinylidene chloride copolymers have exeellent gas, odour and moisture barrier properties impossible to achieve from non-chlorinated waterborne film forming materials. In the barrier packaging area it has a unique position, with proposed replacements being unable to fully match its overall... 

Olesen, P. H., Tender, J. E., Hansen, J. B., Hansen, H. C., Rimvall, K. Bioisosteric replacement strategy for the synthesis of 1-azacyclic compounds with high affinity for the central nicotinic cholinergic receptors. Bioorg. Med. Chem. 2000, S(6), 1443-1450. 

J. P. Hing, S. G. Woolfrey, D. Greenslade, and P. M. C. Wright, Analysis of toxicokinetic data using NONMEM impact of quantification limit and replacement strategies for censored data. J Pharmacokinet Pharmacodyn 28 465 79 (2001). 

From this catalyst performance test the lifetime of SCR catalysts may be predicted, thus providing a replacement strategy for SCR elements. Honeycomb elements or plate-type elements are placed in the oven of a bench-scale setup. With this method the integral activity of an element is obtained. 

Wu H., Liu X., Jaenisch R. (1994) Double replacement Strategy for efficient introduction of subtle mutations into the murine Colla-1 gene by homologous recombination in embryonic stem cells. Proc. Natl. Acad. Sci. USA 91 2819. 

The latter set of biohybiid gels was successfully demonstrated to stimulate growth and proliferation of different cell types in vitro and is currently applied to explore novel cell replacement strategies. 

Maegele M, Schaefer U (2008) Stem cell-based cellular replacement strategies following traumatic brain injury (TBI). Minim Invasive Ther Allied Technol 17 119-131 Marchand F, Tsantoulas C, Singh D, Grist J, Clark AK, Bradbury EJ, McMtihon SB (2(X)9) Effects of Etanercept and Minocycline in a rat model of spinal cord injury. Eur J Pain 13 673-681... 

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