Mannich base derivatives 1-3 were biotransformed through tandem enzymatic reactions by using several microorganisms isolated from Brazilian biomes. The hydrochlorides 1 and 3 produced propiophenone 1a, alpha,beta-unsatured ketone 2c and alcohol (S)-1b (yield 40%, e.e. 81%, Aspergillus terreus). The hydrochloride 2 underwent the Baeyer-Villiger oxidation producing exclusively para-methoxy-phenol by A. terreus and A. niger. The propiophenone la was reduced to their corresponding enantionterically enriched phenylpropanol (S)-1b (yield 65%, e.e. 81%, A. terreus). The para-methoxy-propiophenone 2a afforded Baeyer-Villiger reaction hydrolyzed product, the para-methoxy-phenol (yield 80%, A. terreus). The racemic phenylpropanols 1b,2b were resolved by lipase-catalyzed kinetic resolution (Novozym 435) affording (S)-alcohols 1b,2b and (R)-acetates Id,2d in high enantiomeric excesses (up to 99%) and good yields (40-45%). We screened new microorganisms in biotransformation of Mannich bases, propiophenones and applied enzymatic resolution of phenylpropanols by Candida antarctica lipase. (c) 2006 Elsevier Inc. All rights reserved.