STUDIES ON NEPALESE CRUDE DRUGS .21. ON THE DITERPENOID CONSTITUENTS OF THE AERIAL PART OF SCUTELLARIA DISCOLOR COLEBR

From the aerial part of Scutellaria discolor; eight new neoclerodane d iterpenes (compounds 3, 4, 6, 8, 9, 10, 11 and 12) were isolated toget her with clerodin, dihydroclerodin-I, clerodin hemiacetal (14-hydro-15 beta-hydroxyclerodin), jodrellin A, scutaltisin, squalene, 24-methyle necycloartanol and a mixture of 3-epioleanolic acid and 3-epiursolic a cid. The structures of new compounds were determined by spectroscopic and chemical methods as follows: 3, 15 beta-ethoxy-14-hydroclerodin; 4 , 15 alpha-ethoxy-14-hydroclerodin; 6, (6 -O-acetyl-4,18:11,16:15,16-t riepoxyneoclerodane-6, 15,19-triol (6-O-deacetyl-14-hydro-15-hydroxycl erodin); 8, 6 alpha-O-acetyl-2,19:4,18:11,16: 15,16-tetraepoxy-14-neoc terodene-6,19-diol (19-O-deacetyjodrellin A); 9, 10, 11 and 12, 6 alph a-O-acetyl-15 beta,19 beta-di-O-ethyl-, 6 alpha-O-acetyl-15 alpha,19 b eta-di-O-ethyl-, 6 alpha-O-acetyl-19 beta-O-ethyl- and 6 :11,16:15,16- tetraepoxyneoclerodane-6,15,19-triol, respectively.