- Cyclic α,α-Disubstituted α-Amino Acids with Menthone in Their Side-Chains Linked through an Acetal Moiety and Helical Structures of Their Peptides
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The chiral cyclic α,α-disubstituted α-amino acids, Hms[(–)-Men] and Hms[(+)-Men] with (–)- and (+)-menthones in their side-chains, respectively, were designed and synthesized. Hms[(–)-Men] homopeptides and Hms[(–)/(+)-Men]-containing l-Leu-based peptides were prepared in order to investigate the conformational properties of Hms[(–)/(+)-Men]. The preferred conformations of the Hms[(–)/(+)-Men]-containing peptides were determined by FTIR,1H NMR, and CD spectroscopy in solution, and by X-ray crystallographic analysis in the crystal state. Conformational analysis in solution revealed similar right-handed (P) 310-helical structures for the Hms[(–)/(+)-Men]-containing octapeptides. In the solid state of the hexapeptides, the peptide main-chain structures were mostly similar; however, some differences were observed in the side-chains. The Hms[(–)/(+)-Men] may function as helical inducers, but their side-chain chiralities had only a negligible effect on their helical-screw control of l-Leu-based peptides.
- Furukawa, Kaori,Oba, Makoto,Opiyo, George Ouma,Doi, Mitsunobu,Tanaka, Masakazu
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- A METHOD FOR THE PREPARATION OF FINGOLIMOD
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The invention relates to a method of preparation of 2-amino-2-[2-(4-octylphenyl)- ethyl]propane-1,3-diol (I), comprising opening of the aziridine ring of the intermediates (LVI) by the treatment with organometallic compounds, preferably the Grignard reage
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- Synthesis and study of the behavior of glycosylated gemini surfactants in aqueous media
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The work reported herein deals with the synthesis and physico-chemical studies of a new kind of glycosylated non-ionic gemini surfactants. These compounds derive from tris(hydroxymethyl)aminomethane and bear hydro- or perfluorocarbon tails. The chemical structures of the spacer arm and hydrophobic tails were adjusted in order to specify their impact on the gemini surfactant behavior in aqueous media. The supramolecular systems they form were studied by TEM after negative staining. The length and the rigidity of the spacer arm seem to play a key role in the aggregation behavior of these surfactants in water. With the appropriate modifications, the formation of premicellar associations, micelles, vesicles or various aggregates can be observed.
- Wathier,Polidori,Ruiz,Fabiano,Pucci
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p. 1588 - 1599
(2007/10/03)
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- Synthesis of polymerizable glycolipids derived from Tris (hydroxymethyl) aminomethane: Preparation of polymerized micelles
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We have synthesized a series of new polymerizable glycolipids derived from Tris(hydroxymethyl) aminomethane (TRIS). Galactosylation of TRIS was performed in good yield by means of ultrasounds. Polymerization of 11-N-acrylamido-N-Tris(β-D-galactopyranosyl
- Pucci,Polidori,Rakotomanomana,Chorro,Pavia
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p. 4185 - 4188
(2007/10/02)
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