Non-cross-linked polystyrene-supported 2-imidazolidinone chiral auxiliary: synthesis and application in asymmetric alkylation reactions.

Asymmetric alkylation reactions using non-cross-linked polystyrene (NCPS)-supported 2-imidazolidinone chiral auxiliaries were successfully investigated with excellent diastereocontrol (>99% de). The recovery and the recycling of this soluble polymer-supported chiral auxiliary were achieved in order to produce highly optical pure carboxylic acids.

Synthesis and crystal structure of (E)-2-benzyl-1,3-di-phenyl-iso-thio-uronium iodide.

In the title mol-ecular salt, C20H19N2S+·I-, prepared by the reaction of 1,3-di-phenyl-thio-urea and benzyl iodide, the C-S-C thio-ether bond angle is 101.66 (9)° and electrons are delocalized over the N+= C-N skeleton. The dihedral angle between the aromatic rings attached to the N atoms is 40.60 (9)°. In the crystal, N-H⋯I hydrogen bonds link the components into [100] chains.

Tetra-butyl-ammonium N-benzoyl-6-nitro-1,3-benzothia-zol-2-aminide.

In the title salt, C(16)H(36)N(+)·C(14)H(8)N(3)O(3)S(-), the torsion angles within the cation reveal that one butyl group displays an anti conformation and the other three butyl groups show gauche conformations. The anion is almost planar, with a largest deviation of 0.166 (6) Šfrom the least-squares plane (r.m.s. deviation of fitted atoms = 0.052 Å). In the crystal structure, the component ions inter-act by means of weak inter-molecular C-H⋯O hydrogen bonds.

Synthesis of beta-hydroxy-propenamide derivatives and the inhibition of human dihydroorotate dehydrogenase.

Novel beta-hydroxy propenamides as analogues of the active metabolite of leflunomide (A 771726) were synthesized and evaluated for their inhibitory activity on dihydroorotate dehydrogenase (DHODH) in an investigation into their immunosuppressive activity. Compounds 2a, 3a, and 3h were approximately 4-40 times more potent than leflunomide in their activity while they were-less active than A 771726.

Synthesis and immunosuppressive activity of novel succinylacetone analogues.

This study describes the synthesis of novel enol esters (3) and triketones (4) as analogues of succinylacetone (SA) (Ed- this abbreviation is introduced here based on your use of it in the body of the paper) and the evaluation on the mouse allogeneic mixed lymphocyte reaction (MLR) and the murine model of antigen-induced paw edema formation for immunosuppressive activity. Enol esters (3a-f) were about 2-4 fold more potent than SA in in vitro activity.