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The relative reactivity of enol ether and allylsilane trapping groups toward a ketene dithioacetal derived radical cation has been examined with the use of competition and cyclic voltammetry studies. The competition studies pit the olefinic trapping groups against an alcohol trapping group under conditions of both kinetic and thermodynamic control. With the enol ether trapping group, the chemoselectivity of the competition study favored C–C bond formation under all conditions. With the allylsilane trapping group, the chemoselectivity of the competition study favored C–O bond formation under all conditions. Cyclic voltammetry data was used to show that allylsilane trapping of the radical cation is much slower than enol ether trapping of the radical cation. However, the inefficiency of the allylsilane trapping reaction could not be attributed solely to a slow cyclization. Rather, it appears that a slow second oxidation step plays a role in determining the yield of the reaction.

A series of potential E-selectin antagonists were designed and synthesized based on the bound conformation of sLex, as well as the functional group requirements for anti-adhesion activity. A non-carbohydrate scaffolding using an aryl-cyclohexyl ether which can orient the critical acid and fucose residues in appropriate positions has been investigated. The inhibitory activity of members of this series suggests the feasibility of non-carbohydrate E-selectin antagonists.

The synthesis of (±)-3-[1-carboxy-3α,4α-dihydroxycyclohex-1-en-5β-yl]-2-methylenepropionic acid, a carba analogue of 5-enolpyruvylshikimic acid from methyl (±)-homogabaculinate is described. In addition, both enantiomers of methyl homogabaculinate have been obtained from the Diels Alder reaction of 1- tert -butoxy-carbonyl-1,2-dihydropyridine and the N -acryloyl derivative of Oppolzer's bornane 10,2-sultam.

Syntheses of homogabaculine and homoshikimic acid are described utilising the base mediated ring opening of the cycloadducts of methyl acrylate and N -carbamoyl-1,2-dihydropyridines.

The synthesis of D-fructose 1-deoxy 1-phosphonic acid (2) is described utilising the reaction of diethyl trimethylsilyl phosphite with a novel spiro anomeric epoxide, derived from fructose.

A complete search of the conformational space available to residues with modified amide links was carried out by flexible geometry minimismions of a grid of values of all rotatable bonds. The implications for incorporating these residues in secondary structures were studied.

A brief and efficient new synthesis of 2-substituted 6-11 (R)-hydroxyethyl]-penems is described. The key step involves reaction of an azetidin-2-one-4-disulphide with either stabilized or unstabilized phosphoranes, giving ylids which cyclize with the 1-oxalimide group to give 2 -substituted penems

A synthesis of the phosphonic acid analogues of 3-aminonocardicinic acid is described.

Enantiocomplementary routes to (R)- and (S)-Z-2-amino-5-hydroxy-pent-3-enoic acid lactones are described, starting from D-xylose.

The rearrangement of 7-oxabicyclo[2.2.1]hept-2-enes to 2-oxabicyclo[2.2.1]heptane derivatives, when reacted with iodine and silver acetate, provides further insight into the migratory preferences of alkyl groups involved in Wagner-Meerwein 1,2-bond shifts in unbiased situations.

Differences in erythro/threo -selectivity were assessed foraldol condensations of aldehydes with the lithium salts of cyclopent-2-enone, 2-(5H)furanone, and for Lewis acid catalysed condensations with the derived trimethylsilyoxydienes.

Syntheses of an endothioenkephalin are described. Additionally the first dithionopeptide has been prepared, and its oxidative transformation into a thiazole has been observed.

The regio- and stereo-selective epoxidation of methyl 3,4-dihydrobenzoate has been investigated and a synthesis of racemic methyl 6α-fluoroshikimate from the acetonide of methyl 3,4-dihydro-3α,4α-cyclohexenoate is described. This work has importance for the preparation of 6-substituted shikimic acid derivatives useful in the study of the biosynthesis of aromatic amino acids via the shikimic acid pathway.

New peptide mimetics incorporating eneamine units are described. Tripeptides containing a retroamide and a reduced retroamide have been prepared.

Bis[arylthio]methanes are produced in high yield on treatment of aryl chloromethyl sulphides with neutral alumina.

Two syntheses of (±)-methyl shikimate from the adduct of furan and methyl acrylate are described. One requires the regioselective hydroxylation of (±)-5β,6β-dihydroxy- O , O -isopropylidene-2-methoxycarbonylcyclohexa-1,3-diene and the other cis -dihydroxylation of (±)-5-hydroxy-1-methoxycarbonylcyclohexa-1,3-diene.