Benzilate esters

A variant is represented by the benzilic ester rearrangement, where an alkoxide is used as nucleophile. The alkoxide should not be sensitive towards oxidation. The reaction product is the corresponding benzilic acid ester 5 ... 

In a similar sequence, reaction of ketoester 52 with 2-thienylmagnesium bromide gives a modest yield of the benzilic ester 53. Transesterification of this with aminoalcohol 51, prepared analogously to 45 by starting with methylamine, gives, after quaternization with methyl bromide, heteronium bromide... 

Benzilate esters of piperidinols, as well as those of acyclic aminoalcohols, show similar anticholinergic activity. For example, ester interchange between methyl benzilate and N-methyl-4-piperidinol, followed by quaternization of the resulting ester... 

Baclofen, 121 Bamethan, 39 BAS, 96 BCNU, 12 Becanthone, 413 Beckett-Casey rule, 328 Beloxamide, 56 Benapryzine, 74 Bendazac, 351 Benfurodil, 355, 356 Benorterone, 156 Benoxaprofen, 356 Benperidol, 290 Benproperine, 100 Benzbromarone, 354 Benzetimide, 293 Benzilate esters, 74 Benzilonium bromide, 72 Benzindopyrine, 343 Benzoctamine, 220 Benzodepa, 122 Benzothiadiazines, 383 Benztriamide, 290 Benzydamine, 350 Betahistine, 279 Bioisosterism (see also biological isosterism), 278... 

The piperidyl benzilate esters and phenylcyclohexyl piperidines are synthetic compounds, and have nol been shown to occur naturally. Some authorities do not consider them to be hallucinogens, but active researchers in the field include them among Ihe most active psycholomimetics. 

PIPERIDINIUM, 1-ETHYL-1 - (2-HYDROXYETHYL) -, BROMIDE, BENZILATE (ester) PIPERONAL. DIBENZYLMERCAPTAL PLATINUM (II), DIAMMINEDICHLORO-, cis-POLYDIMETHYL SILOXANE... 

Benzilacetate (acetic acid-benzilester) Benzilbenzoat (benzilic acid-benzil ester) Cedrylacetate... 

Screttas, C. G., Micha-Screttas, M., Cazianis, C. T. The benzilic ester rearrangement. Evidence for a set pathway in the benzilic ester and/or acid rearrangement. Tetrahedron Lett. 1983, 24, 3287-3288. 

The benzilic ester of tropine showed a slower rate of hydrolysis than the tropine ester (11). Values of pK for tropine and -tropine have been recorded and the higher basic strength of tropine was considered in favor of its trans configuration (12). 

USE Benzilate (ester) has been used as an incapacitating agent in chemical warfare Health Aspects of Chemical and Biological Weapons (WHO, Oeneva, 1970) pp 49-51. thekAp CAT Hypotensive, acetate (ester) as cholinergic. 

It is curious that Jowett and Pyman did not prepare benziloyltropeine, since benzilic acid contains the groups, phenyl and alcoholic hydroxyl, which they had found to confer high activity on esters of tropine this ester was studied by Benda and Kraupp (17a) who found that its hydrochloride was as active as atropine sulphate on the cat eye and had, if anything, a slightly more prolonged effect. Kreitmair s results (14) with benziloyl- -tropine have already been mentioned, and several mydriatic benzilic esters of alkamines simpler than tropine will be mentioned later. 

Eucatropine (Euphthalmin) was the first successful mydriatic not containing the tropane nucleus it is the mandelic ester (VI) of the /3-form of 4-hydroxy-l, 2,2,6-tetramethylpiperidine. It is a relatively weak mydriatic and does not paralyze accommodation. The benzilic esters of both the a- and /3-forms of the same 4-hydroxypiperidine derivative, and their methochlorides, were prepared by Ford-Moore and Ing (36). The metho-salts were about 50 % more active than atropine in the mouse, but the more active /3-metho-salt proved to be a very weak mydriatic in man like eucatropine it was not cycloplegic. 

Fromherz (38) investigated esters of 3-diethylamino-2,2-dimethyl-n-propanol ((C2H6)2NCH2C(CHs)2CH20H) and found that the tropic and acetyltropic esters were weak mydriatics, but that their ethobromides were more active. The benzilic ester was more active, and its ethobromide still more active, than the analogous tropic esters. Halpern (39) also reported that the benzilic ester of 2-diethylaminoethanol was mydriatic, so that the... 

In this group the following compounds have been studied four 3-hydroxy-quinuclidine esters with phenylaliphatic acids, i.e. the phenylacetic (IVi), phenylpropionic (IV k), phenoxyacetic (IV1) and cinnamic (IVm) esters, and two esters of 3-hydroxyquinuclidine with diphenylaliphatic acids, i.e. the diphenylpropionic (IVo) and benzilic esters (IVp). 

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