31255-25-1

Four alkyne-functionalized poly(lysine) derivatives have been synthesized and characterized by 1H and 13C NMR spectroscopy. In the first poly(lysine) derivative, phenylpropiolate moieties are directly bound to the aminic arms, whereas in the other derivatives, propargylamine moieties are bound to the aminic poly(lysine) arms through glucaric acid and diethylene glycol (DG) chains, respectively. para-Hydrogenation of the alkyne- functionalized poly(lysine) compounds has been investigated and the results have been discussed in terms of spin lattice relaxation properties of the hydrogenated products. It is shown that the longer the mobile chain separating the unsaturation from the poly(lysine) backbone, the more intense the polarized signals when para-hydrogenation is carried out. This is due to (a) the maintenance of short reorientational times on the unsaturated ends, and therefore a sufficiently long T1 of the protons added during hydrogenation, and (b) the minor effect of steric hindrance by the poly(lysine) backbone that decreases interaction of the unsaturation with the catalyst, allowing higher hydrogenation rates. The Royal Society of Chemistry 2005.

Certain embodiments of the invention provide antioxidant-based diacids and polymers comprising glycol groups as described herein, and methods of use thereof. In certain embodiments the polymers described herein are formulated as microspheres or hydrogels. Described herein is the chemical incorporation of antioxidants, e.g., coumaric acid, ferulic acid, and sinapic acid, into a polymer backbone for use, e.g., in applications for localized release and rapid delivery. As provided, the chemical composition of the linker molecules used (of which hold together two bioactives via ester linkages) may be used to vary the hydrophilicity of the polymer. The bioactive release rate may also be altered for a tunable release delivery system, allowing for increased bioactive release compared to other linkers previously utilized.

Ferulic acid-based polymers with aliphatic linkages have been previously synthesized via solution polymerization methods, yet they feature relatively slow ferulic acid release rates (～11 months to 100% completion). To achieve a more rapid release rate as required in skin care formulations, ferulic acid-based polymers with ethylene glycol linkers were prepared to increase hydrophilicity and, in turn, increase ferulic acid release rates. The polymers were characterized using nuclear magnetic resonance and Fourier transform infrared spectroscopies to confirm chemical composition. The molecular weights, thermal properties (e.g., glass transition temperature), and contact angles were also obtained and the polymers compared. Polymer glass transition temperature was observed to decrease with increasing linker molecule length, whereas increasing oxygen content decreased polymer contact angle. The polymers' chemical structures and physical properties were shown to influence ferulic acid release rates and antioxidant activity. In all polymers, ferulic acid release was achieved with no bioactive decomposition. These polymers demonstrate the ability to strategically release ferulic acid at rates and concentrations relevant for topical applications such as skin care products.

New macrocyclic lactones were synthesized by reaction of 3-bromo-5-(5-tert-butyl-2-hydroxybenzyl)biphenyl-4-ol with appropriate polyethylene glycol-based dicarboxylic acid dichlorides, and their complexes with Mg(ClO4)2·6H2O, Pb(SCN) 2, NaClO4·H2O, and KClO4 were prepared. The macrocyclic ligands were evaluated as extractants in the transfer of Li+, Na+, K+, Cu2+, Ni 2+, and Hg2+ picrates from aqueous to organic phase.

Bis(acylketene) (3) thermally generated from Meldrum's acid derivative (2) underwent intramolecular [4+2] cycloaddition to produce bridged dehydroacetic acid derivative (4). Heating 4 with methylamine and ammonia afforded crown ether type pyridinophanes (5) and (6) (12-crown-4), respectively. Reaction of the ketene (3) with (ethylene glycol)s afforded macrolactones (11-13) in satisfactory yields. Molecular structures of 4 and 6 are discussed based on X-Ray crystallographic analysis.

The X-ray structures of three potential molecular tweezers, C20H24N2O5 (1), C20H20N6O13 (2) and C28H32N2O13 (3), differing only by the substituents on the terminal aromatic moieties, display three as yet unreported arrays. Hydrogen bonding with co-crystallized water molecules as well as van der Waals interactions between terminal aromatic moieties lead to specific packing patterns, namely: (i) a membrane-like architecture of associated molecular tapes in 1 · 2H2O, (ii) coupled right- handed and left-handed helices in 2 · H2O and (iii) a stepped arrangement provided by a back-to-back pairing in (3)2 · H2O. Molecular modelling of individual molecules in vacuo shows that the most stable conformers of 1-3 intrinsically display attractive interactions between the terminal aromatic groups, which stabilize a pseudocavity suitable for incorporation of a guest compound.

Described is the preparation of five sLex dimers and five sLex carboxylic acids by coupling chemoenzymatically synthesized amino-substituted sialyl Lewis x (sLex) derivative 4 to homobifunctional cross-linkers 20-24 of varying chain length. 20-24 were obtained by alkylating low-molecular-weight oligoethylene glycols with tert-butyl bromoacetate and subsequent transformation of the di-tert-butyl esters into disuccinimide esters. The products were assayed for inhibition against binding of a sLea-polymer to immobilized E- and P-selectin. In the E-selectin assay all dimers had lower IC50 values than the sLex monomer. The results show that comparable binding enhancements can be obtained with linkers of completely different length and rigidity. In the P-selectin assay four of the five sLex carboxylic acids displayed significantly improved inhibitory potency. The lowest IC50 value was observed for the compound with the shortest spacer between the sLex moiety and the additional carboxylate, being ca. 20-40 times more potent than unmodified sLex. These findings should be of importance for the design of new multivalent forms of sLex as well as sLex mimetics as high-affinity selectin ligands.

Synthesis and spectral properties of optically active acyclic ligands, containing two (S)-phenylalanine residues (3a-f) are described.The synthesis is achieved by two different routes.Conformational studies in different solvents are performed by dilution and temperature-dependent experiments of 1H and 13C NMR spectroscopy.