The dynamic chemical diversity of the numerous elements, ions and molecules that constitute the basis of life provides wide challenges and opportunities for research. In a document, author is Visser, TJ, introducing its new discovery. HPLC of Formula: https://www.ambeed.com/products/630-19-3.html.
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. One of the oldest and most widely used commercial enzyme inhibitors is aspirin, which selectively inhibits one of the enzymes involved in the synthesis of molecules that trigger inflammation. 630-19-3, you can contact me at any time and look forward to more communication. HPLC of Formula: https://www.ambeed.com/products/630-19-3.html.
Reference:
Quinuclidine – Wikipedia,
,Quinuclidine | C7H13N | ChemSpider