Modified di- and tripeptides of the C-terminal portion of oxytocin and vasopressin as possible cognition activation agents
摘要:
A number of peptides and modified peptides were synthesized and studied for their ability to reverse electroconvulsive shock-induced amnesia in rodents. A few of these peptides were selected for secondary evaluation in tests of short-term memory in rats and aged rhesus monkeys. A number of the peptides and modified peptides were active in the amnesia reversal test. In selected secondary tests, however, the chosen compounds failed to show significant activity in enhancing memory. New methods for preparing methyleneamino and methyleneoxy isosteres of peptides are reported. Other modified peptides also included methylenethio, methylenesulfonyl, and ethylene isosteres in place of the normal peptide amide bond.
Modified di- and tripeptides of the C-terminal portion of oxytocin and vasopressin as possible cognition activation agents
摘要:
A number of peptides and modified peptides were synthesized and studied for their ability to reverse electroconvulsive shock-induced amnesia in rodents. A few of these peptides were selected for secondary evaluation in tests of short-term memory in rats and aged rhesus monkeys. A number of the peptides and modified peptides were active in the amnesia reversal test. In selected secondary tests, however, the chosen compounds failed to show significant activity in enhancing memory. New methods for preparing methyleneamino and methyleneoxy isosteres of peptides are reported. Other modified peptides also included methylenethio, methylenesulfonyl, and ethylene isosteres in place of the normal peptide amide bond.
Improved methods for synthesizing bifunctional chelates of tetraazamacrocycle derivatives and intermediates thereof are disclosed as well as novel tetraazamacrocycle derivatives and intermediates thereof.
Improved methods for synthesizing bifunctional chelates of tetraazamacrocycle derivatives and intermediates thereof are disclosed as well as novel tetraazamacrocycle derivatives and intermediates thereof.
Synthesis and characterization of a new lanthanide based MRI contrast agent, potential and versatile tracer for multimodal imaging
作者:Satya Narayana Murthy Chilla、Sophie Laurent、Luce Vander Elst、Robert N. Muller
DOI:10.1016/j.tet.2014.06.126
日期:2014.9
In the present work a modular pathway towards the synthesis of a new versatile MRI contrast agent is reported and its physico-chemical properties are described. Two different functional groups were attached on two arms of the gadolinium 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate (DOTA) in order to get a platform able to bind one probe designed to target specific biological marker and a fluorescent molecule likely to be used for optical imaging. The nuclear magnetic relaxation dispersion (NMRD) profile, the oxygen-17 relaxometric NMR study and stability assessment versus transmetalation of the Gd-complex show that this new contrast agent has a relaxivity and transmetalation stability similar to Gd-DOTA. (C) 2014 Elsevier Ltd. All rights reserved.
[EN] 1 , 4 -BIS (CARBOXYMETHYL) -6- ' BIS ( CARBOXYMETHYL) AMINO ! -6 -METHYL- PERHYDRO-1 , 4 DIAZEPINE (AAZTA) DERIVATIVES AS LIGANDS IN HIGH RELAXIVITY CONTRAST AGENTS FOR USE IN MAGNETIC RESONANCE IMAGING (MRI )<br/>[FR] AGENTS DE CONTRASTE A RELAXIVITE ACCRUE