Method of making asymmetric de ring intermediates for the synthesis of camptothecin and… Grant US-5428166-A United States of America 27 Jun 1995
Pyridinecarboxaldehyde D-ring intermediates useful for the synthesis of camptothecin and… Grant US-5321140-A United States of America 14 Jun 1994
Alkoxymethylpyridine d-ring intermediates useful for the synthesis of camptpthecin and… Grant US-5254690-A United States of America 19 Oct 1993