Synthesis, Stability, and Biological Studies of Fluorinated Analogues of Thromboxane A.

Platelet activation results in the generation of thromboxane A (TxA), which promotes thrombus formation by further amplifying platelet function, as well as causing vasoconstriction. Due to its role in thrombus formation and cardiovascular disease, its production is the target of antiplatelet drugs such as aspirin. However, the study of TxA-stimulated cellular function has been limited by its instability ( = 32 s, pH = 7.

Synthesis of 1,4,7,10-tetra-azacyclododecan-1,4,7,10-tetra-azidoethylacetic acid (DOTAZA) and related "clickable" DOTA derivatives.

Herein, we report the synthesis of two enantiomeric DOTAZA esters and a related DOT3AZA ester. These compounds are tunable analogues of the well-known chelator DOTA and can be easily functionalized through click chemistry of the side-chain azide groups. Like DOTA, DOTAZA forms complexes with various di- and trivalent metals, as demonstrated in the synthesis and structural analysis of CuDOTAZA and the preparation of GdDOTAZA.

Model system for cell adhesion mediated by weak carbohydrate-carbohydrate interactions.

The multivalent carbohydrate-carbohydrate interaction between membrane-anchored epitopes derived from the marine sponge Microciona prolifera has been explored by colloidal probe microscopy. An in situ coupling of sulfated and non-sulfated disaccharides to membrane-coated surfaces was employed to mimic native cell-cell contacts.The dynamic strength of the homomeric self-association was measured as a function of calcium ions and loading rate.

Peroxide solvation by a toroidal lithium inverse crown ether complex assembled by multidentate polyimido sulfonates.

In this communication we present the synthesis of the inverse crown ether complex [Li(2)O(2)·Li(4){CH(2)(N(Me)CH(2)S(NtBu)(2))(2)}(2)] (1) which is able to accommodate peroxide in a torus of lithium ions.

Novel multidentate sulfur-nitrogen ligands with enhanced complexation properties.

Di(tert-butyl)sulfur diimide and bis(trimethylsilyl)sulfur diimide were reacted with different metalated amines to form versatile novel multidentate ligand systems with side-arm donation. Their complexation properties in terms of ligand design, denticity and the cation size are discussed. We report herein the synthesis and structure elucidation of [(tBuN)(2)S{LiMe(2)N(C(6)H(4))S(NtBu)(2)}(2)] (1), [(Li{Me(2)N(C(6)H(4))S(NSiMe(3))(2)})(2)] (2), [(Li(thf){Me(2)N(C(6)H(4))S(NSiMe(3))(2)})(2)] (3), [(Li{2-PicS(NSiMe(3))(2)})(2)] (4), [(Li{Me(2)N(CH(2))(2)N(Me)S(NSiMe(3))(2)})(2)] (5), [(Na{Me(2)N(CH(2))(2)N(Me)S(NSiMe(3))(2)})(2)] (6) and [(K{Me(2)N(C(6)H(4))S(NSiMe(3))(2)})(2)] (7).