GB806692A - New alkaloids - Google Patents

Abstract

The invention comprises (1) the extraction of alkaloids from Voacanga sp. (especially root or trunk bark) with either a water-immiscible feebly polar or non-polar organic solvent or a polar organic solvent and/or water (with or without a strong organic or inorganic acid), the extract then being concentrated if desired and further extracted with a solvent of the other type; and (2) the three alkaloids so obtained, viz: A, C22H28O3N2; B, C42H52O5N4; C, C20H26O3N2, defined in the Specification i terms of their physical properties. The yield of alkaloids is improved by a treatment of the plant material with aqueous or alcoholic alkali before the extraction; ammonia, lime, caustic soda, sodium carbonate and bicarbonate are suitable. The solvent of the first type above may be diethyl or isopropyl ether, benzene, toluene, dichlorethane, chloroform, methylene chloride, trichlorethylene, methyl or ethyl acetate, or a mixture of these. The solvent of the second type may be water, methanol or ethanol, and may contain hydrochloric, sulphuric, phosphoric, acetic, formic, lactic, propionic, tartaric or citric acid or an acid salt of a polybasic acid, e.g. mono-sodium sulphate or phosphate. The alkaloids may be obtained from the extracts by adsorption on ion-exchangers or chromatography, and purified by recrystallization. Salts may be prepared by treatment with acid in the presence of a diluent (e.g. water, benzene, methanol or ethanol) or by double decomposition. Suitable acids are hydrohalic, chloric, perchloric, sulphuric, phosphoric, formic, acetic, propionic, butyric, benzoic, tartaric, oxalic, lactic, citric, ascorbic, salicylic, methane-sulphonic, p - toluenesulphonic and camphosulphonic. Examples are given of the extraction of alkaloids from V. obtusa and V. africana; other species that may be used are V. condiflora, V. scheinfurthii and V. tonarii. Specification 806,691 is referred to.ALSO:Pharmaceutical compositions having cardiotonic and hypertensive action contain at least one alkaloid obtained from Voacanga sp. and having the formula C22H28O3N2, C42H52O5N4 or C20H26O3N2; the three alkaloids are defined in the Specification in terms of their physical properties. The compositions may be in the form of solutions in water or physiological serum, granules made with lactose or gum arabic, suppositories or powder. The alkaloids may be present as salts with inorganic or organic acids, a number of which are specified. Specification 806,691, [Group IV (b)], is referred to.