In this report we set out to extend recent studies on substituted PAC analogues produced by the fermentation of aromatic aldehydes with Saccharomyces cerevisiae. The medium selected contained glucose as a carbon source for the biotransformation, and sodium pyruvate as an inhibitor for alcohol dehydrogenase, the enzyme responsible for the conversion of the carbinol to a benzyl alcohol derivatives. An investigation of sodium cyanoborohydride for a selective reductive amination was carried out on these carbinols to produce the corresponding ephedrine analogues. Poor selectivity was apparent for this reagent but when the reduction products were converted to their hydrochloride derivatives the optically pure compounds separated readily by fractional crystallisation. Their pharmacological activity was investigated using commercial ephedrine as a reference compound. The synthesised (-) ephedrine had an identical activity to the commercial compound, while the substituted analogues all had a slightly lower activity, with the exception of (-)-4-chloro ephedrine which showed a stronger antispasmodic effect. The stereoselectivity of the synthesis and the enantiomeric purity of the resolved compounds were investigated by high field nuclear magnetic resonance spectrometry employing chiral praseodymium shift reagents .