ENDOTHALL THIOANHYDRIDE

(3a-alpha,4-beta,7-beta,7a-alpha)-hexahydro-4,7-epoxybenzo(c)thiophene-1,3-d

4,7-epoxybenzo(c)thiophene-1,3-dione,hexahydro-,(3a-alpha,4-beta,7-beta,7a-al