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The first total synthesis aimed at the naturally occurring eicosanoid bicycle mucosin is reported. A practical route has been devised allowing the issues relating to the previous assignment of stereochemistry to be examined. X-ray crystallography was performed on a late stage intermediate to pinpoint the topological relationship displayed by the featured bicyclo[4.3.0]non-3-ene scaffold.

Several microorganisms produce small quantities of polyunsaturated hydrocarbons and such natural products are of interest. Starting from the ethyl ester of eicosapentaenoic acid, the total synthesis of the natural product (all-Z)-hentriaconta-3,6,9,12,15,19,22,25,28-nonaene has been achieved in eight steps and 15% overall yield. The synthesis is based on a stereoselective Wittig reaction and confirms the all-Z-configuration of the nine double bonds in this highly unsaturated natural product.

A series of substituted arenes containing remote chiral centers were screened as substrates for toluene dioxygenase (TDO). The absolute stereochemistry of the new metabolites was determined by chemical and spectroscopic correlation with synthetic standards. There was no evidence for kinetic resolution; enantiomers were indiscriminately processed by the enzyme to diastereomeric pairs, which were separable upon derivatization. Some of these new metabolites are useful as synthons for morphine synthesis. Full experimental details are reported for those new compounds stable to isolation and for derivatives of those that are unstable.

Several aromatic substrates containing remote chiral centers were subjected to toluene and naphthalene dioxygenase expressed in blocked mutants and recombinant organisms yielding cis-diol metabolites with little or no kinetic resolution.

Several catechols have been prepared directly from aromatic precursors by treatment with the recombinant organism Escherichia coli JM109 (pDTG602), which expresses both toluene dioxygenase (TDO) and dihydrocatechol dehydrogenase (DHCD), the first two enzymes in the natural biodegradation pathway of aromatics by Pseudomonas species. The yields and the ease of preparation of these compounds are compared with traditional chemical methods. For three of the products, the E value and EMY (effective mass yield, is defined as the percentage of the mass of desired product relative to the mass of all non-benign materials in its synthesis, see ref. 9) are calculated and compared with those obtained by traditional methods to indicate the green component of the preparation. Potential for direct introduction of the catechol unit to various natural product synthons is discussed.