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Glycosides of uncommon aglucones, characterized by the Ph-C5-Ph skeleton, were isolated from the rhizomes of some African Hypoxis species. HPLC analysis indicated the occurrence of these compounds in other Hypoxidaceae. On the basis of structural evidence and biogenetic considerations, the aglucones of these glycosides can be considered as norlignans, derived from the union of two phenylpropanoid units in positions alpha, beta' or beta, gamma' and with the loss of the terminal carbon of a chain. Several Hypoxis species are used in traditional medicine as antiinflammatory and antitumor drugs and, recently, preparations based on lipophilic extracts of H. rooperi have been introduced into the market for the treatment of prostatic hypertrophy.

The antifeedant activity of a series of 21 chalcones, flavanes, and flavanones isolated from the generaLonchocarpus andTephrosia (Leguminosae) was assessed by behavioral and electrophysiological bioassays against larvae ofSpodoptera littoralis andS. exempta. The antifeedant activity is related to the molecular structure of the compounds, and possible modes of interaction with the insect taste receptors are discussed.

From the leaves of Strychnos pseudoquina (Loganiaceae), isorhamnetin (1) and a new biflavone (2) named strychnobiflavone were isolated together with the alkaloids diaboline and 11-methoxydiaboline.

From the rhizomes of HYPOXIS OBTUSA two monoglucosides having the same aglycone as hypoxoside, 1-(3',4'- dihydroxyphenyl)-5-(3'',4''-dihydroxyphenyl)-1-pen-ten-4-yne, have been obtained. By methylation followed by hydrogenation they have been transformed into the same compound, 1-(3'-methoxy-4'- O-beta- D-glucopyranosyl-phenyl)-5-(3''-4''-dimethoxyphenyl)-pentane, likewise obtainable through partial hydrolysis of hypoxoside.

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.

The interaction of jatrophone with sRNA from Escherichia coli has been investigated through UV, CD, and 1H NMR measurements. The results obtained show that the interaction with jatrophone increases the stability of the polynucleotide. It appears that the optical properties of jatrophone depend upon the jatrophone/nucleotide ratio. The observed behaviour can only be explained by the existence of different types of interaction between jatrophone and sRNA. Even for a jatrophone/nucleotide ratio as low as 0.17 the 1H NMR spectra show a multiplicity of resonances that can only be explained by the simultaneous existence of two different binding modes involving the jatrophone molecules.

Tingenone and horminone, two natural quinonoid substances, inhibited the in vitro growth of Trypanosoma cruzi, 30 microM drug concentration producing total inhibition of growth. Tingenone inhibited total uptake and incorporation of [3H]thymidine, [3H]uridine, L-[3H]leucine into parasite macromolecules. Other quinonoids assayed were either less effective (abruquinone A) or even quite inactive (visminone B and ferruginin B). Investigation of several mechanisms for the cytotoxic action of tingenone pointed to the interaction with DNA as the most likely factor involved. Tingenone also inhibited the growth of Crithidia fasciculata, but the drug was significantly less active on this organism than on T. cruzi.

From Abuta grisebachii Triana & Planchon, Menispermacea used by Sanama tribe for the preparation of curare, five bisbenzylisoquinoline alkaloids have been isolated; four of them are tertiary (peinamine and three new alkaloids, 7-O-demethylpeinamine, N-methyl,7-O-demethylpeinamine and macolidine) and one is a new quaternary alkaloid called macoline. Their structures have been elucidated on the basis of chemical reactions and spectroscopic data.

A highly purified kallikrein from rat kidney was obtained by a multi-step purification procedure including gel filtration on Sephadex G-100, chromatography on Whatman CM-32 and DE-32 celluloses and Sephadex G-100 superfine. Molecular weight of 40,000 was estimated by sodium dodecyl sulfate polyacrylamide disc gel electrophoresis. On the purified enzyme the aminoacid analysis was determined. Some chemical differences between renal kallikrein and the most abundant rat urinary kallikrein were illustrated.

The alkaloid and procyanidin composition of Uncaria sp. from eastern Peru, used in folk medicine was studied. Five alkaloids have been separated and identified as pteropodine, speciophylline, isopteropodine, uncarine F and isomytraphylline, all belonging to the oxindole group characteristic of the Rubiaceae. Moreover (--) epicatechin and four dimeric procyanidins A1, B1, B2 and B4 have been shown to constitute the polyphenolic fraction of the plant extract.

Kallikrein was purified from horse kidney by several steps of chromatographic procedure and by affinity chromatography on Sepharose-Concanavaline. Horse urinary kallikrein was previously purified by DE-32 hydroxylapatite and by Sephadex G-100 gel filtration. On the purified final sample of renal and urinary kallikrein the aminoacid composition and the gel electrophoretic molecular weight were determined. The ratio in micronMoles between each aminoacid residue of both hydrolyzed renal and urinary kallikrein of horse is about 1,00 +/- 0,30. Except for Pro, 1/2 Cys and basic aminoacid residues a good proportion was obtained. It is confirmed that the different molecular weight, respectively 47,500 for renal kallikrein and 28,000 for the urinary enzyme is an artefact of the different procedures used for the purification of horse kallikrein.

In every country drug control depends on the existence of technical norms which are generally represented by the Pharmacopoeia. In effects, since the beginning of XIII century, when the profession of pharmacist was for the first time established by law, pharmacopoeias have had not only the purpose of supplying the composition and the preparation of drugs, but also to establish and enforce the quality of the drugs. In the present times the pharmacopoeias adopted throughout the world by the different countries are intended mainly as a codex of specifications for the control of drug quality. These pharmacopoeias are national, regional and international. Nevertheless several difficulties can be found in the use of the pharmacopoeias for control of drugs, owing to the fact that not all the drugs, allowed and in therapeutical use are included in pharmacopoeias, and also because, in some cases, the final control is not sufficient to establish drug quality especially in the case of biological preparations. The existence of a Formulary or "Codex", beyond pharmacopoeia, may be of help for the control authorities but generally is not sufficient. Some suggestions are made in order to envisage a modern pharmacopoeia, considered as a dynamic collection of specifications of drug quality, always up to date, and thus in condition to fulfil its task for the need of the drug control by the health authorities in the aim of a better protection of public health.

Akagerine (3) was isolated from three different species of South American Strychnos: from S. gardneri A. D.C. (Rio de Janeiro, Brazil), together with 11-methoxydiaboline (2); from S. jobertiana Baillon (Brazil), together with diaboline (1): and from S. parvifolia D.C. (Bahia, Brazil).

Seeds and/or roots of eleven species of Leguminosae, mainly Tephrosiae, were examined. Prenylated chalcones and flavanones were isolated from Lonchocarpus nitidus and L. neuroscapha seeds; rotenoids from Lonchocarpus spruceanus, Piscidia mollis and a Tephrosia sp.; demethylhomopterocarpin from Canavalia bonariensis (Phaseoleae). No flavonoids or rotenoids were found in L. nelsii, L. rugosus, T. multijuga (seeds), Millettia grandis (Tephrosieae) and in Xeroderris stuhlmanii (Dalbergieae).

Two glycosides, isolated in good yields from roots of Macfadyena unguis-cati (L.) A. G entry (syn. Doxantha unguis-cati (L.) Miers), gave on hydrolysis the same aglycone (quinovic acid). The sugar moieties have been identified as fucose and glucose respectively. This is the first time that saponins have been found in Bignoniaceae and their occurrence may account of the use of the plant in folk medicine.

A new bisbenzylisoquinoline alkaloid has been isolated from a curare of the Upper Orinoco region. The curare is made by Indians from an unknown plant (probably Menispermacea) and is kept on arrow tips. The structure of the alkaloid, named peinamine, has been elucidated on the basis of its chemical reactions and spectroscopic data (N.M.R., M.S. and O.R.D.).