Five hydroxylated analogues of tamoxifen [1, (Z)-2-[p-(1,2-diphenyl-1-butenyl)phenoxy]-N,N-dimethylethylamine] and its geometric isomer were prepared by reaction of protected hydroxy-alpha-ethyldeoxybenzoins with 4-[2-dimethylamino) ethoxy]phenylmagnesium bromide, followed by acid-catalyzed dehydration-deprotection and chromatographic separation of isomer mixtures. Estrogen receptor binding affinity and estrogenic and antiestrogenic activity of each of the compounds were determined in the rat, in comparison with 4-hydroxytamoxifen (2). The new compounds had a wide range of receptor binding affinities, with that of 3-hydroxytamoxifen (6c), the most strongly bound, approaching that of estradiol. The trans isomers 6a,b were more strongly bound than were the cis isomers 7a,b. Antiestrogenic activity was seen in all compounds except 7b. This was also true for estrogenic activity, except that in 6c this activity was also substantially reduced. Maximal antiestrogenic effectiveness of 6c occurred at a 10-fold greater daily dose (50 micrograms/rat) than that required for maximal effect of 2.

A series of seven N,N'-disubstituted bispidines, structurally analogous to the inner (B and C) rings of sparteine (1) and encompassing a range of lipophilicity in which 1 was centered, has been compared to 1 in regard to antiarrhythmic potency and acute toxicity. Several of the bispidines were of comparable potency, and all but one were somewhat less toxic than 1. The ability of the mononitrate salts of 1 and bispidines 6 and 7 to bind calcium and magnesium cations in Me2SO-d6 solvent has been evaluated by proton magnetic resonance analysis. No binding could be demonstrated under these conditions, which suggested that pharmacologic effects of these compounds may be due to properties other than direct binding of these cations.

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Disopyramide was resolved by fractional crystallization of its diastereomeric bitartrate salts from methanol-acetone. Diastereomeric sulfonamides prepared from (+)-camphor-10-sulfonyl chloride and the primary amines obtained by LiAlH4 reduction of the resolved bases were separable by high-performance LC and were used to show that within experimental error resolution of disopyramide was complete. The absolute configuration was determined by X-ray crystallography. (+)-[(2R)-(-)-4-(Diisopropylamino)-2-(2-pyridyl)-2-phenylbutyramide (+)-(2R,3R)-bitartrate] crystallizes in space group P212121: a = 14.789 (4), b = 18.151 (4), c = 9.878 (2) A; Z = 4: Dx = 1.225, Dm (flotation C6H6/CCl4) = 1.226 g cm-3. The structure was solved by direct methods. The enantiomeric bitartrates were tested for antiarrhythmic properties. The enantiomeric bitartrate salts were equally effective in prolonging the effective refractory period (ERP) of rabbit ventricle. At 3 x 10(-6) M, the (-)-bitartrate [from (2S)-(+)-disopyramide] increased the ERP 21.8 +/- 6.3 ms and the (+)-bitartrate [from (2R)-(-)-disopyramide] increased the ERP 25.8 +/- 3.6 ms. At 1.5 x 10(-5) M no significant difference was noted, as the increases in the ERP were 41.2 +/- 8.9 and 50.5 +/- 6.3 ms for the (-)- and %+)-bitartrate, respectively.

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A series of aromatic ring substituted bispidinebenzamides, 2--10, was prepared by condensation of N-methyl- or N-n-butylbispidine with the appropriate acid chlorides. These compounds were initially evaluated in mice for acute toxicity and for their ability to protect against chloroform-induced ventricular fibrillation. All compounds had significant activity, which was optimized in 2, 3, and 5. These last compounds had potencies and LD50/ED50 ratios comparable to those of a standard antiarrhythmic, disopyramide. However, their potencies in increasing the effective refactory period in isolated rabbit atria were considerably less than that of disopyramide.

Although fatty acids are recognized to be important substrates for mammalian myocardial metabolism (1, 2), the influence of cardioactive drugs on lipid metabolism has received relatively little attention. Moreover, species variation of response to antiarrhythmic drugs are poorly known. Quinidine in concentrations of more than M lowers the production of 14CQ2 from palmitate UJ4C in dog heart slices (3) and markedly depresses the myocardial contractile force in cat's papillary muscle preparations (4) and isolated perfused rabbit's heart (5). Gamma-is a drug similar to quinidine in that it depresses the myocardial contractile force (5) , alters the electrical properties of the myocardial membrane, such as threshold and the rate of rise of the action potential in isolated atrial preparations from rabbit heart (6), and lowers the rate of glucose oxidation and its utilization by the myocardium (7).The purpose of this investigation is to study the effect of quinidine and disopyramide .on oxygen consumption and utilization of palmitate by heart slices from rats, rabbits, and dogs.Materials and Methods. Adult, male (except as noted), nonfasting animals were used throughout this study. The species were Sprague-Dawley rats weighing 150-280 g, albino New Zealand white rabbits weighing 1.8 1 Supported by grants from Florida Heart Associa-