In an effort to determine if there is a specific conformational structure which is most effective at the appropriate active physiological site, the synthesis of a group of sterically restricted analogs was undertaken. A portion of the polymethylene carbon skeleton of glutaric acid was replaced by selected aromatic carbons in benzenedicarboxylic acids to produce a series of ridged conformers, and the relative plant growth regulating properties of these derivatives were determined.

The principle objective of this study is to conduct a definitive investigation into the cycloaddition of allenes and ketenes, with particular emphasis on halogenated ketenes.

The central nature of nicotinamide in metabolic processes as a part of the NAD and NADP coenzyme systems prompted the synthesis of a series of N-nicotinyl- and N-isonicotinyl-N'- (substituted)ureas as potential metabolite antagonists of the vitamin. The compounds which were synthesized may be represented by the following general structure, where R = hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, t-butyl, n-hexyl, cyclohexyl, phenyl and a-naphthyl. The observed toxicity of the N-nicotinyl-N'-(substituted)urea analogs may be attributed to the formation of a non-functional N-nicotinyl-N'-(substituted)urea-NAD analog through an exchange reaction catalyzed by NAD-ases in the cell. Support for this view was obtained by an in vitro enzymic synthesis of Nnicotinyl- N'-ethylurea-NAD analog employing N-nicotinyl-7- 1 4CN'- ethylurea. The labeled derivative was characterized through spectral, chromatographic, and chemical reaction studies.