Choline phenyl ethers

It was concluded that the nicotinic activity of choline phenyl ether and of choline o-tolyl ether is a reflection of the ability of the molecule to assume a "planar" conformation when interacting with the ganglionic nicotinic receptor. In contrast, the inactive 2,6-xylyl ether of choline cannot assume this planar disposition. Evaluation of additional conformation-ally restricted aiyl choline ethers (44-47) revealed that only the piperidine derivative (47) is a ganglionic stimulant (98). 

K. Fukui, Ch. Nagata, and A. Imamura, Science, 132(3419), 87 (1960). Electronic Structure and Nicotine-Like Stimulant Activity in Choline Phenyl Ethers. 

In an immunochemical approach to learning more about the receptor site, an antibody was prepared against choline phenyl ether 12.86) in the rabbit. Unfortunately, when this antibody was used as a model for nicotinic receptors, it was found unable to distinguish between muscarinic and nicotinic agents, nor between agonists and antagonists (Marlow, Metcalf and Burgen, 1969). 

In an immunochemical approach to learning more about the receptor site, an antibody was prepared against choline phenyl ether 13,63) in the... 

Additional ring-substituted phenyl ethers of choline were described by Hey (94). Clark and coworkers (97) studied conformationally restricted racemic bicyclic choline phenyl... 

The importance of the ether oxygen for interaction with the esterophilic site of N-ChR is confirmed by the great nicotinic potency of phenyl ethers of choline (12) ... 

The phase transfer catalyzed alkylation reaction of dodecyl phenyl glycidyl ether (DPGE) with hydroxyethyl cellulose (HEC) was studied as a mechanistic model for the general PTC reaction with cellulose ethers. In this way, the most effective phase transfer catalysts and optimum reaction concentrations could be identified. As a model cellulose ether, CELLOSIZE HEC11 was chosen, and the phase transfer catalysts chosen for evaluation were aqueous solutions of choline hydroxide, tetramethyl-, tetrabutyl-, tetrahexyl-, and benzyltrimethylammonium hydroxides. The molar A/HEC ratio (molar ratio of alkali to HEC) used was 0.50, the diluent to HEC (D/HEC) weight ratio was 7.4, and the reaction diluent was aqueous /-butyl alcohol. Because some of the quaternary ammonium hydroxide charges would be accompanied by large additions of water, the initial water content of the diluent was adjusted so that the final diluent composition would be about 14.4% water in /-butyl alcohol. The results of these experiments are summarized in Table 2. 

Computational studies made by Kier and his coworkers, most recently on amino acids,62,63 dopamine,thyroxine, 5 oxotremorine, and phenyl choline ether,are close to views shared by medicinal chemists since the calculations deal with the conformations of drug agents. Work such as Kler s is valuable since not only can the most stable conformations accessible to a drug molecule be calculated (these can frequently be determined by X-ray or n.m.r. techniques) but also less stable, potentially undetected conformations available to a molecule could be Indicated. At least one of the... 

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