Patent ID: 8507697

Claim:
A process for preparing artemisinin, comprising the steps of: preparing a mixture comprising (i) a dihydroartemisinic acid derivative of formula (I) wherein X is O Y is formula (II) R 1 is hydrogen; a C 1 -C 12 alkyl group which is linear or branched or a C 3 -C 10 cycloalkyl group, said alkyl group being unsubstituted or substituted by one or more substituent(s) selected from a C 1 -C 6 alkyl group and a halogen; a trifluoromethyl group; a cycloalkylalkyl group where cycloalkyl and alkyl are as defined above; a C 2 -C 12 alkenyl group which is linear or branched, said alkenyl group being unsubstituted or substituted by one or more substituent(s) selected from a C 1 -C 6 alkyl group and a halogen; a C 5 -C 14 aryl or heteroaryl group, said aryl or heteroaryl group being unsubstituted or substituted by one or more substituent(s) selected from a C 1 -C 6 alkyl group and a halogen; an arylalkyl group where aryl and alkyl are as defined above; or a heteroarylalkyl group where heteroaryl and alkyl are as defined above; R 3 is OR 1 where R 1 is as defined above; (ii) at least one organic solvent and (iii) a photosensitizer, subjecting said mixture to photooxidation by means of a light source, and recovering the artemisinin thus obtained.