2,4(3H,5if)-Furandione (/3-tetronic acid, 1) undergoes a base-catalyzed aldol condensation with aromatic aldehydes to afford the 1:1 condensation products 3-(arylmethylene)-2,4(3if,5H)-furandiones 2. The 1:1 condensation products 2 are also obtained when the reaction is acid catalyzed, and this constitutes a more convenient synthesis of 2. The furandiones 2 are formed as a mixture of two geometric isomers, whose structures have been tentatively assigned on the basis of *H NMR data. Preliminary investigations dealing with condensations of 1 with aliphatic aldehydes reveal that, under all conditions employed, the products contain 2 equiv of 1 and 1 equiv of the aldehyde.Also explored are the cycloaddition reactions of 2 with triethyl phosphite, which lead to the novel furo[3,4-d]-l,2oxaphospholene ring system.

Studies on dehydrogenase enzyme inhibition have been extended with the design, synthesis, and correlation analysis of 7-[(substituted-benzyl)oxy]-, 7-[(substituted-phenethyl)oxy]-, and 7([substituted-phenoxy)ethoxy]-4-hydroxyquinoline-3-carboxylic acids. Sixteen new congeners and the fifteen molecules previously synthesized have been tested against cytoplasmic malate dehydrogenase and lactate dehydrogenase, as well as against mitochondrial malate dehydrogenase. The lipophilic congeners show a clear specificity for inhibition of the mitochondrial enzyme. Correlation analysis of the data on the three enzymes allows a comparison of the binding sites in quantitative terms, while examination of the data on inhibition of ascites tumor cell respiration affords an indication of membrane transport. A newly developed high-pressure liquid chromatography based retention index is compared to the octanol-water pi constant as a model for hydrophobic interactions.

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The 13C NMR speetra were determined and signals assigned to the various carbons of the alkamines veracevine, germine and zygacine derived from steroidal alkaloids of the ceveratrum class. Assignment of signals was aided by analysis of the partially relaxed spectrum of cevagenine 9,12,14-orthoacetate-3,16-diacetate.

A Salem, Ind., utility devised a generic, widely applicable approach to tasteand-odor control that paved the way to site-specific treatment, resulting in higher quality water and fewer customer complaints. BY DaviD a. isaacs, Russell G. BRown, william a. RatajczYk, nathan w. lonG, john h. RoDGeRs jR., anD james c. schmiDt solve taste-and-odor Problems with customized treatment