An HPLC-system to measure the e.e. of trans-3-(benz-1,3-oxazol-2-yl)cyclopentan-1-ol6 , cis-3-(benz-1,3-oxazol-2-yl)cyclopentan-1-ol 38, 3-(benz-1,3-oxazol-2-yl)cyclopentan-1-one8 and 2-(benz-1,3-oxazol-2-yl)cyclopentan-1-ol 7 simultaneously in the fermentation mixture of the substrate 2-cyclopentyl-1,3-benzoxazole 5 with Cunninghamella blakesleeana DSM 1906 is presented. The scope and limitations of the benzoxazole cleavage reactions is discussed.