9(10)-Carboxyoctadecylamine and 9(10)-aminomethyloctadecanoic acid: Synthesis and polymerization to polyamides with lateral substitution

9(10)-Carboxyoctadecylamine (I) and 9(10)-aminomethyloctadecanoic acid (II) have been prepared from selectively hydroformylated oleonitrile and oleic acid, respectively. Polymerization of I gave a transparent hard, somewhat brittle, polyamide, whereas polymerization of II gave a soft, rubbery polymer that flowed slowly at room temperature. Copolymers of I with II had properties reflecting those of the component homopolymers, although II exercised a disproportionate softening effect. The same was generally true of copolymers of I or II with nylon-66 salt, caprolactam, and 9-aminononanoic acid. The copolymer of I with 25 mole % nylon-66 salt was transparent, was also elastic, and could be either drawn into fibers or made into a coherent film. The properties of the two amino acids and of their polymers agreed with those expected from simpler alkyl-substituted amino acids.     

Analyses of lipids and oxidation products by partition chromatography. Fatty acid hydroperoxides

A liquid partition chromatographic method was developed to isolated and determine hydroperoxides in autoxidized fatty acids or their methyl esters. By the use of benzene containing 2 to 4% methanol as the mobile solvent, the hydroperoxides were separated from unoxidized fatty acids or methyl esters and from secondary and polymeric decomposition products. In the analyses of oxidized fatty acids, diethyl ether was necessary to elute the secondary decomposition products. Saponification of autoxidized fatty esters destroyed the peroxides as determined iodometrically, but the resulting acids contained a fraction which was eluted in the same position as hydroperoxide acids. Evidence showed that this fraction is a monomeric hydroxy fatty acid containing conjugated cis-traux and trans-trans unsaturation. Fatty ester hydroperoxides were isolated chromatographically in yields and purity comparable to those reported in the literature by countercurrent distribution. The concentrations of methyl linoleate hydroperoxide determined chromatographically were smaller than indicated by the peroxide value and diene conjugation of the autoxidized methyl linoleate. This is a laboratory of the Northern Utilization Research and Development Division, Agricultural Research Service, U.S. Department of Agriculture.     

Potent bicyclic lactam inhibitors of thrombin: Part I: P3 modifications

Peptidomimetic inhibitors of general structure 1 have been prepared. Optimization of the binding affinities of these compounds through variation of the P3 hydrophobic residue is described. Selected substituted bicylic lactams displayed interesting pharmacological profiles both in vitro and in vivo.     

Dopaminergic activity of some apomorphine analogs

The dopaminergic activity of ten apomorphine analogs was studied in rats lesioned unilaterally with 6-hydroxydopamine in the nigro-striatal system. Of these ten compounds, N,N-dimethyl-5,6-dihydroxy-2-amino-tetralin (M-7), N-methyl-5,6-dihydroxy-2-aminotetralin (M-8) and N,N-dimethyl-4,5-dihydroxy-2-aminoindan (DDAI) exhibited potent dopaminergic stimulant activity by causing the rat to turn to the unoperated side. The turning behavior of apomorphine, M-7, DDAI and d-amphetamine were antagonized by haloperidol. M-7 and DDAI also induced pecking in pigeons and their effects were also blocked by haloperidol. It is concluded that M-7, M-8 and DDAI are direct acting central dopaminergic agents.