In homogeneous catalysis, catalysts are in the same phase as the reactants. Catalysts allow a reaction to proceed via a pathway that has a lower activation energy than the uncatalyzed reaction.111-12-6, Name is Methyl oct-2-ynoate, SMILES is CCCCCC#CC(OC)=O, belongs to quinuclidine compound. In a document, author is Visser, TJ, introduce the new discover, Name: Methyl oct-2-ynoate.
Stereoselective synthesis and biodistribution of potent [C-11]-labeled antagonists for positron emission tomography imaging of muscarinic receptors in the airways
Quantitation of muscarinic receptors in the lungs in vivo with positron emission tomography (PET) is of clinical interest. For that purpose we decided to develop [C-11]-labeled ligands with a high affinity (K-D < 0.1 nM). Three quaternary muscarinic antagonists, racemic N-methylpiperidin-4-yl 2-cyclohexy-2-2-hydroxy-2-phenylacetate methiodide 1a (pK(B) = 10.39), its (R)-isomer 1b (pK(B) = 11.08), and (R,R)-quinuclidin-3-yl 2-cyclohexyl-2-hydroxy-2-phenylacetate methiodide 2 (pK(B) = 11.28), were labeled by reacting [C-11]CH3I With their tertiary amine precursors. The enantiomerically pure tertiary amine precursors were prepared by stereoselective synthesis starting from (R)-(-)-mandelic acid. In vitro binding assay of 1b and 2 demonstrated that both ligands bind with very high affinity to the muscarinic receptor subtypes M(1), M(2), and M(3). They are more potent than the muscarinic antagonist (R)-N-methylquinuclidinyl benzilate ((R)-MQNB). Distribution studies with la, 1b, and 2 in control and atropine-treated male Wistar rats demonstrated significant specific binding (90-99% of total issue uptake) in tissues containing cholinoceptors (heart, intestine, lung, pancreas, spleen, stomach, submandibular gland). Because the tissue/plasma concentration ratios of 1b are most favorable, this ligand was used for further evaluation. Analysis of plasma samples showed a very rapid clearance (t(1/2) = 0.3 min) of the radioligand 1b and a relatively slow appearance of a hydrophilic metabolite. At 15 min postinjection of 1b, analysis of heart, lungs, and liver showed that respectively 99%, 88%, and 8% of the tissue radioactivity corresponded with the parent compound. Ligand 1b appears to be an excellent candidate for PET studies of mAChR receptors in heart and lungs. Enzymes are biological catalysts that produce large increases in reaction rates.Do you like my blog? If you like, you can also browse other articles about this kind. Thanks for taking the time to read the blog about 111-12-6, Name: Methyl oct-2-ynoate.
Reference:
Quinuclidine – Wikipedia,
,Quinuclidine | C7H13N | ChemSpider