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21.
177Lu-labeled receptor avid peptides and monoclonal antibodies have been effectively used in targeted tumor therapy, owing to the ideally suited decay properties and favourable production logistics of 177Lu [T½ = 6.65 days; Eβ(max) = 497 keV (78.6 %); Eγ = 208 keV (11.0 %)]. The specific activity of 177Lu produced by the (n,γ) route is one of the important criteria, which determines the efficacy of 177Lu-labeled receptor-avid biomolecules. The present article highlights that the specific activity of (n,γ) produced 177Lu cannot be calculated by simply dividing the produced activity by the mass of the target irradiated, unlike other (n,γ) produced medical radioisotopes and there is a significant enhancement of specific activity due to the burn up of the Lu target during irradiation, which is an added advantage towards the utilization of 177Lu in receptor specific therapeutic radiopharmaceuticals.  相似文献   
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We have developed second-generation monomers 1 and 2 and improved conditions for rapidly and simultaneously closing multiple diketopiperazines on solid support. These new conditions involve either the microwave heating of a suspension of solid-supported amino-tetrafluoropropyl esters in acetic acid/triethylamine catalyst solution or continuous flow of catalyst solution through the resin, heated in a flow cell apparatus. We demonstrate that the new monomers 1 and 2 can be combined with the new conditions easily to synthesize previously inaccessible hetero and homo spiro ladder oligomers 3 and 4 and others.  相似文献   
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Fluoroboric acid supported on silica gel (HBF4‐SiO2) catalyzes efficiently the three component condensation of an aldehyde, a 1,3‐dicarbonyl compound and urea or thiourea to afford the corresponding 3,4‐dihydropyrimidin‐ 2(1H)‐ones and thiones in high yields. The ambient conditions, fast reaction rates, and excellent product yields are the important characteristics of this reaction.  相似文献   
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Methods for a facile high-yielding synthesis of substituted pyrazolo[3,4-c]pyridines from 2-bromo-5-fluoropyridine are described, along with a brief mechanistic discussion for the key cyclization step. The methods utilize inexpensive commercially available starting materials and unlike previous methods, are more suitable for SAR work and scale-up.  相似文献   
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An environmentally benign method for O‐tert‐Boc protection of alcohols and phenols catalyzed by MgO–ZrO2 nanoparticles under solvent‐free conditions is described. A variety of phenols, alcohols (aliphatic and aromatic) were converted to corresponding O‐tert‐Boc products in good to excellent yield (50–95%). The present protocol is expedient, simple, and efficient under solvent‐free conditions. The MgO–ZrO2 Nps are easily prepared from inexpensive precursors, and are reusable, recyclable and chemoselective. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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Some platinum (IV) complexes [Pt(L)2Cl2] [where, L=2-aminopyridine-N-thiohydrazide (L1), (2-aminopyridine-N-thio)-1,3-propanediamine (L2), benzaldehyde-2-aminopyridine-N-thiohydrazone (L3) and salicylaldehyde-2-aminopyrtidine-N-thiohydrazone (L4)] have been synthesized. The thiohydrazides, thiodiamine and thiohydrazones can exist as thione-thiol tautomer and coordinate as a bidentate N-S ligand. The ligands found to act in monobasic bidentate fashion. Analytical data reveals that metal to ligand stoichiometry is 1:2. The complexes have been characterized by elemental analysis, IR, mass, electronic and 1H NMR spectroscopic studies. In vitro antibacterial and cytotoxic study have also been carried out for some complexes.  相似文献   
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