Le charbon actif, le L-(+)-bornésitol est recristallisé dans MeOH. F. 2060, α₀²·⁵ + 32,1, IR. comparaison avec un échantillon authentique. Quantités isolées: 0.5 à 2% du matériel sec. La présence du L-(+)-bornésitol est uniforme à l'intérieur de la section Coelanthe et pourrait être caractéristique de cette dernière. De plus, elle est particulièrement intéressante pour la chimiotaxonomie au niveau des familles constituant l'ordre des Contortae ou Gentianales, le L-(+)-bornésitol n'ayant été décelé que dans deux familles proches des Gentianacées, les Apocynacées et les Rubiacées. Seeds of Crotalaria juncea and several other species of this genus (C. medicagenia, C. anagradis, C. striata and C. laburnifolia) revealed, among other amino acids, the presence of an unidentified compound in varying concentration that was strongly ninhydrin positive. Earlier investigators isolated from C. juncea seeds an optically inactive amino acid which they identified as β-hydroxy-N-methyl-(±)-norvaline. Pant and Kapur also observed an unidentifiable peak in the seeds of C. medicagenia while analysing them for their free amino acids in an automatic analyser. With a view to establish the identity of this compound with Adams and Gianturco's optically inactive amino acid, the unidentifiable ninhydrin positive compound was isolated from C. juncea seeds in pure form. The present communication describes the details of its isolation and assignment of structure. A new amino acid has been isolated from C. juncea seeds. The MS of the compound reveals an (M + H) ion at m/e 148 indicating the molecular weight of 147 (C₆H₁₃NO₃). The presence of ions at m/e 130 and 102 respectively and metastable ions at 114.1 and 71.1 further prove this. The important ion is m/z 84 which is the loss of H₂O + COOH⁻. This proves that in addition to the COOH group, the compound has a hydroxyl group. This can also be seen by the small peak at m/e 112 for loss of 2H₂O from (M + H). These observations suggest that the compound could be 5-hydroxy-2-aminohexanoic acid. The NMR spectrum of the compound performed at 100 mc and at pH 10 showed five groups of peaks in the ratio of 3:2:2:1:1 at δ 1.16 (t, J = 6 Hz), δ 1.52 (m), δ 1.80 (m), δ 3.61 (m), δ 3.79 (q, J = Hz). These are assigned to the terminal methyl, the 4-methylene, the 3-methylene and the 2- and 5-hydrogens respectively. The splitting patterns appear straightforward; the 3 and 4 methylene groups exhibit complex coupling with each other and the adjacent hydrogens at C-2. Fortunately, the methylene group at C-4 is coupled to the hydrogen at C-5 in a manner that allows the coupling between the C-5 hydrogen and the C-6-methyl group (6 Hz) to be dominant. Proof that this assignment is correct is provided by the observation that the multiplet at δ 3.61 moves downfield at δ 3.72 at pH 2. Thus it is concluded that the compound is 5-hydroxy-2-aminohexanoic acid. This compound (under the name of δ-hydroxy norleucine) was obtained by Takita and Naganawa from various llamycins. Hudlicki and Kakaé synthesized the compound by the hydrolysis of either ethyl-2-ethoxy-carbonyl-2-acetamido-5-fluorocaproate or 2-ethoxy-carbonyl-2-acetamido-5-caprolactone. Although the elementary analysis and the empirical formula, molecular weight etc. reported by these authors concur with our data, their reported IR bands do not appear to check with ours. However, this could be explained on the basis that the synthesized material probably contained four stereoisomeric components. Plant. Desmodium cephalotes Wall (tribe: Lotoideae). The plant material was supplied by Messrs United Chemical and Allied Products, Calcutta. A voucher specimen has been preserved at the Pharmaceutical Chemistry Research Laboratory. Source: The plant grows in India in the Northern Circars, Hills of the Deccan and Carnatic, and Western Ghats up to 3000 ft, in forest undergrowth, especially with teak in the South, with Sal in the North. Uses: Different parts are used in the Indian system of medicine as a cure for dysentery, in bronchial spasms and coughs, as a central stimulant. Previous work. On sister species, viz., D. pulchellum, D. gangeticum, D. triflorum, D. gyrus, D. tiliaefolium, D. floribundum. Plant part examined. Stem-roots, leaves. In a typical experiment, air-dried and powdered stem-roots (3.2 kg) were continuously extracted first with light petroleum, then with ethanol (16 hr. each). The extractives were separately processed according to a previously described procedure. Separation of the mixture of alkaloids from the different fractions was accomplished by gradient-pH extraction, fractionation into phenolic and non-phenolic bases over Amberlite-IRA 400 (HO⁻) resin column, and by column and layer chromatography. The identity of the individual entities was established by co-TLC with authentic markers, correspondence of melting point where possible, spectral evidence (UV, IR, PMR, MS), and derivatization.