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Enantiomerically pure C -alkyl amides derived from cis and trans cycloalkane-1,2-dicarboxylic acids, respectively, have been synthesized and their behavior as organogelators has been investigated. These compounds include cis/trans diastereomeric cyclobutane and cyclohexane derivatives with the aim to explore the influence of the ring size as well as the relative configuration in their hierarchical self-assembly to form gels. High resolution H NMR spectroscopy studies allowed the determination of the dynamics of the gelation process in [D ]toluene and the sol-gel transition temperature. The morphology and size of the aggregates have been investigated and results have shown that, in the case of cyclobutane derivatives, the cis/trans stereochemistry is not relevant for the gelation behavior and the properties of the soft-materials obtained, but it is remarkable for cyclohexane diamides, which are better organogelators. The four compounds produce chiral aggregates despite that two of them are meso achiral molecules. We show herein that this fact is an example of stochastic symmetry breaking induced by sonication. The self-assembly of these molecules has been modelled providing information and support about the structure and the chirality of the aggregates.

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Myocardiac remodelling and vascular retinopathy develop early and in parallel in hypertensives, and both developments appear to involve determinants including body mass index and 24-h maximum systolic BP. WCH subjects, as defined by current ABP-based criteria, have cardiac and retinovascular characteristics different to normotensive subjects. Stricter criteria are needed to discriminate between hypertensives with and without the systemic developments that constitute the immediate source of risk to the hypertensives individual.

The first example of a new protocol for the incorporation of γ-amino acids into peptides is reported. It involved a shikimic acid based stereoselective synthesis polyhydroxylated-2-nitromethylcyclohexanecarboxylic acids, which were directly incorporated into peptides.

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Spironucleosides are a type of conformationally restricted nucleoside analogs in which the anomeric carbon belongs simultaneously to the sugar moiety and to the base unit. This locks the nucleic base in a specific orientation around the N-glycosidic bond, imposing restrictions on the flexibility of the sugar moiety. Anomeric spiro-functionalized nucleosides have gained considerable importance with the discovery of hydantocidin, a natural spironucleoside isolated from fermentation broths of Streptomyces hygroscopicus which exhibits potent herbicidal activity. The biological activity of hydantocidin has prompted considerable synthetic interest in this nucleoside and also in a variety of analogues, since important pharmaceutical leads can be found among modified nucleoside analogues. We present here an overview of the most important advances in the synthesis of spironucleosides.