Salary Clau, Bridge Clau, As Well As The Synthesis Of Their Optical Isomers And Derivatives

The total syntheses of neoclausenamide, dehydro-ctausenamide and optically active dehydroctausena-mide have been completed. During synthesis, the ste reoselective reduction of neoctausenamidone has been studied in detail. As a result, neoctausenamide or isoneoclausenamide can be provided with a selectivity >90% by applying appropriate reducing methods. Their overall yields based upon benzaldehyde were 18.0 -Z4.4% and 19.8²8.0% respectively.Uehydroctausenamide was obtained by two routes. One was through selective sulfonation of C_?-hydroxyt group of neoctausenamide, followed by intramotecutar disptace-ment in the presence of 2.6-tutidine. The yietd based upon benzaldehyde was 11.9-16.1%. The second method was thorugh the direct dehydration of isoneortausenamico by triphenytphosphine-diethytazodicarboxytate .the overail yield from oenzatdehyae was 6-8% The optirally active denydroctausenamind and its enantiomer were obtained either by resotution of the intermediate, neorlausenamid one or starting from cinnawyt atcohol through sharp-less epoxidation. Based on the configuration of the epoxide obtained, the absolute configurations of natural dehydroctausenamide and related optically active compounds were elucidated The structure modification of neoctauseuamine and dehydroclausenamide on the substitution of C_?-phenyt group have been carried out for searching for more effective drugs. Fourteen derivatives of neoclausena mide have been synthesized.Pharmacological study of the derivatives and six optically active parent compounds are in progressing...