E. J. Shellard

Alkaloids from Mitragyna speciosa (Korth.)

bases yielded mitragynine (Beckett, Shellard & Tackie, 1965) and subsequently corynantheidine, isomitraphylline and a second isomer of mitraphylline which we have named speciophylline (I). The picrate mother liquors yielded ajmalicine, an isomer of mitragynine named speciogynine (IIa), a 9-methoxy derivative of corynantheine-like structure named puynanrheine (IIb) and unidentified alkaloids. The ether-insoluble bases yielded mainly mitraphylline.

The alkaloids of the leaves of Mitragyna inermis (Willd.) O. Kuntze

The leaves of Mitragyna inermis (Willd.) O. Kuntze have been examined for alkaloids and shown to contain routundifoline, isorotundifoline, rhynchophylline, isorhynchophylline, ciliaphylline, rhynchociline, speciophylline, a small amount of uncarine F, mitraciliatine and traces of a second indole alkaloid which appears to be of the corynanthine type. There is also a polar compound present, Dragendorff positive, which remains on the base line when subjected to thin‐layer chromatography with the usual solvent systems used for the mitragyna alkaloids.

The morphology and anatomy of the flowers of Mitragyna ciliata Aubr. et Pellegr. and Mitragyna stipulosa (D.C.) O. Kuntze

The morphology and detailed anatomy of the flowers of Mitragyna ciliata Aubr. et Pellegr. and Mitragyna stipulosa (D.C.) O. Kuntze have been described. Although the histological features are almost identical, the two species can be differentiated by the morphology of their calices.

The relationship between thin‐layer chromatographic behaviour and the stereochemistry of some heteroyohimbine alkaloids

ANUMBER of thin‐layer chromatography systems have been used to distinguish and identify some indole and oxindole alkaloids isolated from various species of the genus Mitragyna (Shellard & Phillipson, 1964). It has been suggested moreover that a relationship exists between the stereochemistry of these alkaloids and their behaviour on thin‐layer chromatograms (Phillipson & Shellard, 1966). Two new heteroyohimbine alkaloids, mitrajavine and hirsutine, have recently been isolated from Mitragyna species (Shellard, Beckett, Tantivatana, Phillipson & Lee, 1966) and their behaviour on thin‐layers has been compared with some related alkaloids of known stereochemistry. Based on this, certain suggestions have been made about the stereochemistry of these two new alkaloids.

IPOMOEA—AN ANATOMICAL STUDY

A detailed anatomical investigation has been made of the dried sliced tubercles of Ipomoea orizabensis (Pelletan) Ledanois which constitutes the drug known in commerce as Ipomoea. A list of the characteristic features of the powdered drug is given