Charles H. Stirton

Castanospermine in Alexa species

Abstract Castanospermine, a physiologically active polyhydroxylated indolizidine alkaloid first isolated from seeds of Castanospermum australe, has been isolated from the dried pod of Alexa leiopetala and tentatively identified in seven other species of the same genus.

Isolation from atelia herbert-smithii pittier (sophoreae, leguminosae) and x-ray structure of cis-1-amino-3-hydroxymethyl-cyclobutane-1-carboxylic acid, an achiral non-protein amino acid

Abstract barcis -1-Amino-3-hydroxymethyl-cyclobutane-1-carboxylic Acid (1) has been isolated from Atelia herbert-smithii Pittier (Leguminosae) and its structure determined by spectroscopic and X-ray crystallographic methods. By a study of the 1H NMR spectrum of the crude extract, the relative amount of (I) to that of methanoproline in the plant was shown to be 1 to 1.15.

Alkaloid distribution in seeds of Ormosia, Pericopsis and Haplormosia

Abstract Alkaloid profiles were determined by capillary gas chromatography/mass spectrometry in seeds of 15 Ormosia species, of both South American and Asian origin, as well as in three Pericopsis species and Haplormosia monophylla . All samples contained alkaloids, and a total of 31 compounds were identified, comprising 23 lupine-type and seven Ormosia -type quinolizidine alkaloids, and the dipiperidine alkaloid, ammodendrine. Homopodopetaline, which has not previously been characterized as a natural product, was detected in extracts prepared from O. coutinhoi , O. macrophylla and O. semicastrata seeds. Ormosia -type quinolizidine alkaloids were restricted to the genus Ormosia , but were not observed in four members of this genus. The Pericopsis species accumulated predominantly α-pyridone quinolizidine bases, while two collections of H. monophylla contained mainly lupine-type quinolizidine alkaloids of the sparteine/lupanine class.

A chemotaxonomic survey of the tribe psoraleeae in africa

A study of the leaf flavonoids, furanocoumarins and essential oils of 51 species (three genera) of the tribe Psoraleeae (Fabaceae) has provided chemical data to support the recent subdivision of the large worldwide genus Psoralea into a number of segregate genera. The flavonoid patterns in most species were very similar, consisting largely of proanthocyanidins and complex mixtures of flavone O- and C-glucosides. Psoralea repens, the only maritime species to be examined, is unique in containing only rutin. Three isoflavones (daidzein, formononetin and genistein) were of widespread occurrence. The genera Psoralea and Otholobium, which could not be separated on flavonoid data, were clearly demarcated by their essential oils. Furanocoumarin patterns were useful for the characterization of species.

Polhillia, a new genus of papilionoid legumes endemic to South Africa

Subgenus Plecolobium C.H. Stirton of Lebeckia Thunb., described originally to accommodate the unusual species Lebeckia waltersii C.H. Stirton, is broadened to include five species and is raised to generic rank as Polhillia C.H. Stirton based on the species Polhillia waltersii (C.H. Stirton) C.H. Stirton. The following new combinations are made: Polhillia waltersii (C.H. Stirton) C.H. Stirton and P. connatum (Harv.) C.H. Stirton. P. pallens C.H. Stirton and P. canescens C.H. Stirton are described as new.

Melolobium involucratum (Fabaceae), a new combination for South Africa

Psoralea involucrata Thunb., a rare legume endemic to the Cape, was transferred to Argyrolobium by William Harvey. Recent evidence suggests that this species is better placed in Melolobium in the tribe Crotalarieae and not in Argyrolobium (Genisteae). The affinities of this species are discussed and the new combination Melolobium involucratum (Thunb.) C.H. Stirton is made.

Notes on the genus Otholobium (Psoraleeae Fabaceae)

Thirty-one new combinations are made in Otholobium, a genus related to Psoralea, Bituminaria and Cullen in the tribe Psoraleeae. One new species is described: Otholobium swartbergense C.H. Stirton. It is a small lax, much branched shrublet with 6–15-flowered (purple) hemispherical inflorescences, endemic to the Groot Swartberg Mountains.

A NEW SPECIES OF PSORALEA (LEGUMINOSAE : PAPILIONOIDEAE) FROM THE WESTERN CAPE, SOUTH AFRICA

A new species, Psoralea peratica, from the Western Cape Province in South Africa is described and illustrated.

Leaf anatomy of the genusPsoralea sensu stricto(Psoraleeae, Papilionoideae, Leguminosae)☆

Abstract Leaf anatomy is described from 17 species of Psoralea sensu stricto which includes four species of the genus Hallia Thunberg. Species of the two genera share many characters including the presence of rod-shaped crystals, similar stipule structure and a possible continuum in secretory cavity anatomy ranging from a small and non-trabeculate to a large and trabeculate form. Hallia species are distinguished by the presence of large tannin cells in the bundle sheaths and a narrow length:width ratio of palisade cells. In the light of other floral evidence this is considered insufficient to separate the two genera, a view confirmed by cluster analysis. Thus, Salters proposal of 1939 for their amalgamation is supported. Leaf anatomy of herbaceous species is compared with that of seedlings of Psoralea sp. to assess the possibility that the herbaceous species may have arisen through neoteny from species that are trees or shrubs. Comparative venation studies between stipules and scale leaves suggest that the scale leaf form arose from pinnate-leaved ancestors by leaf reduction.