From the seeds of Phytolacca americana, acentonylidene americanin. A was isolated and its structure elucidated mainly by spectroscopic methods. This compound is not a genuine constituent but formed in the tissue on heating with acetone.

Ginsenosides Rb1, Rb2, Rc, Rd, Re, Rf and Rg1 were effectively isolated from ginseng root by preparative liquid chromatography (LC) on two PrepPAK-500/c18 cartridges in series and semipreparative LC on a .mu. Bondapak cabohydrate analysis column, a .mu.Bondapak C18 column or a .mu. Porasil column. The identities of the isolated ginsenosides were confirmed by analytical high-performance liquid chromatography (HPLC) and infrared spectrophotometry. By this method large scale isolation of pure ginsenosides was efficiently accomplished.

Quercetin-3-O-${\beta}$-D glucofuranoside, mp 243-$6^{\circ}$, was isolate dfrom leaves of Polygonum sachalinense Fr. Schm and characterized on the basis of its spectral data. This is the second report of its occurrence in nature.

To develop potent anitumor polysac-charides from higher hungi of Korea the alcohol precipitated polysaccharides, which were obtained from hot water extracts of shake-cultured mycelia of eight species of basidiomycetes, were subjected to antitumor screening tests, using sarcoma 180 as a tumor cell. When administered i. p, at the dose level of 20mg/kg/day for ten days into the mice which were implanted with $1{times}10^{8}$ cells of sarcoma 180 twenty-four hour before the start of polysaccharide injection, the polysaccharides of Plutcus cervinus ISA-Pc-1004, Pleurotus pulmonarius, Hydnum repandum ISA-Hr-1006, and Laccaria laccata ISA-LI-1008 respectively showed inhibition ratios of 62.0%, 51.7%, 64.8%, and 57.8%. They were selected for further study, while those of Pancillus serotina ISA-Ps-1012, Laccaria amethystina ISA-La 1001, Pholiota adiposa ISA-Pa-1010, and Lepista spISA-Ls-1007 respectively showed inhibition ratios of -9.3%, 25.3%, 27.3% and 33.0%.

To develop new potent antitumor substancces with low toxicity from natural products, especially from higher fungi of Korea, the carpophores of some wild basidiomycetes were collected and the antitimor test for their polysaccharides was done. The dried carpophores were extracted with hot water, and from the extracts, crude polysaccharides were obtained by alcohol precipitation. The alcohol precipitated crude polysaccharides were partially purified by dialysis and then used as the samples for antitumor tests. Among tested, the polysaccharide of Laccaria laccata, Trametes sanguineus, Armlliariella mellea, Clitocybe in fundibuliformis, and Xeromphalina campanella respectively showed the inhibition ratio of 75%, 72%, 94% 55%, and 47% when administered i. p. once dailly for ten days at the dose level of 20mg/kg/day into the mice implanted with $10^{6}$ cells of sarcoma 180/mouse. However, those of Craterellus cornucopiodes, Daedaleopsis confrogosa, and Coriolus sp. showed almost no activities.

Nicotelline was directly analyzed from the crude tobacco extract by metastable studies. The metastable transitions of nicotelline were investigated by MS with DADI/MIKE spectrometry.

Thank you for inviting me as a guest speaker to this 30th anniversary of the Pharmaceutical Society of Korea. I take it as a compliment to may firm F. Hoffmann-La Roche and Co., Which, has not only dicovered and introduced the benzodiazepines, but has since then been continually in the fore-front of this research. As may subject is going to be "Current Trends in Benzodiazepine Research" I will try to have a look into pending problems. The history of the benzodiazepines has been told several times (e. g. Sternbach, Haefely).