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2-Deoxy-α -d- glucose-1-phosphate, 3-deoxy-α -d- arabino-hexose-1-phosphate, 4-deoxy-α -d- lyxo-hexose-1-phosphate, and α -d- lyxose-1-phosphate were synthesised chemically, and evaluated as substrates for a recombinant G D P-mannose pyrophosphorylase (Salmonella enterica, group B, cloned in Escherichia coli). The deoxy derivatives were all substrates for the enzyme, with slightly reduced Vmax values but significantly higher Km values than those recorded for the native substrate, mannose-1-phosphate. The pyrophosphorylase was used for the synthesis of GDP-mannose analogues GDP-2-deoxy-glucose and GDP-lyxose on a milligram scale.

The enantioselective reduction of acetophenone was studied in two different ways. Chemical borane reduction using a homogeneously soluble polymer-bound oxazaborolidine catalyst was carried out in a continuously operated membrane reactor and yielded (R)-phenylethanol in good enantiomeric excess with high space–time yields. An enzymatic reduction using a dehydrogenase two-enzyme system as the catalyst and formate as the hydrogen source was carried out in an extractive bi-membrane reactor and yielded (S)-phenylethanol in excellent enantiomeric excess with a low enzyme consumption. A comparison of the two systems with respect to space–time yield, total turnover number and other parameters is made.

Polymer enlarged oxazaborolidines that are homogeneously soluble were used as catalysts for the enantioselective reduction of ketones in a continuously operated membrane reactor equipped with a nanofiltration membrane. The amount of chiral product per mole of catalyst could be enhanced from 10 up to 560 moles (≡0.18 mol% catalyst). The chiral alcohols are obtained in good to excellent ee and space–time yield (up to 99% ee and 1.4 kg/[Lreactor volume×day)].

A two-enzyme system consisting of a cyclohexanone mono-oxygenase from Acinetobacter NCIMB 9871 and a protein-engineered formate dehydrogenase for the regeneration of the cofactor NADPH was used for the synthesis of chiral e-lactones. 4-Methylcyclohexanone was used as the model substrate yielding ( S )-(−)-5-methyl-oxepane-2-one with high chemical and enantiomeric purity. Syntheses were carried out in a repetitive-batch reactor with integrated bubble-free aerationby means of a thin-walled silicon tube.

( S )-2-N,N-dibutylamino-3-butyl-1-[4-(4-Phenylmethoxy)-phenyl]heptan-3-ol 3 based on ( S )-tyrosine has been synthesised. For the diethylzinc addition to both aliphatic and aromatic aldehydes, high enantiomeric excesses up to 95% were obtained.