Patent ID: 8497088

Claim:
A process for the synthesis of a semi-synthetic β-lactam compound from a nucleus and a side chain selected from the group consisting of D-phenylglycine and D-dihydro-phenylglycine in the form of a side chain ester and an enzyme catalyzing the coupling of the side chain ester to the nucleus comprising the steps of (a) converting a free side chain selected from the group consisting of D-phenylglycine and D-dihydro-phenylglycine with an alcohol to form a mixture comprising the corresponding side chain ester; (b) forming the semi-synthetic β-lactam compound by mixing the mixture obtained in step (a) with a nucleus and the enzyme to form the semi-synthetic β-lactam compound, with the proviso that the side chain ester formed in step (a) is not isolated as a solid intermediate.