Penicillium spinulosum epoxidation

Finally, a very useful and industrially interesting epoxidation which deserves special attention is the stereospecific epoxidation of cis-propenylphosphonate. Eighteen species of Penicillium, one of Oidium and one of Paecilomyces were found to effect this reaction, which affords directly (-)-fosfomycin, a broad-spectrum antibiotic. Using the strain Penicillium spinulosum MB 2843 at optimum culture conditions, a 90 % efficiency (based on olefin charged, 0.5 g If1) was obtained after 6 days, leading to a product claimed to be optically pure11481. 

Once the problems of product toxicity were surmounted by sophisticated process engineering, microbial epoxidation of alkenes became also feasible on an industrial scale [1153, 1154]. The latter was achieved by using organic-aqueous two-phase systems or by evaporation for volatile epoxides. For instance, the epoxy-phosphonic acid derivative fosfomycin [1155], whose enantiospecific synthesis by classical methods would have been extremely difficult, was obtained by a microbial epoxidation of the corresponding olefinic substrate using Penicillium spinulosum. 

---