Norbert Neuss

Vinca alkaloids XXXV. Desacetoxyvinblastine a new minor alkaloid fromVinca rosea L. (Catharanthus roseus G. Don)

Auf Grund spektroskopischer Untersuchungen konnte die Struktur eines neuen Alkaloids ausVinca rosea L. als Desacetoxy-VLB aufgeklärt werden.

Pharmacological properties of recanescine, a new sedative alkaloid from Rauwolfia canescens Linn.

Summary A new alkaloid isolated from Rauwolfia canescens, recanescine, appears to lack the methoxyl group in the C-ll position of reserpine. Preliminary evidence indicates that this compound retains the characteristic pharmacologic activity of reserpine. Thus, the methoxyl group is not essential for the sedative and hypotensive action of reserpine. Note added in proof Since submission of this manuscript, Stoll and Hofmann have reported the isolation of a new alkaloid, canes-cine, which is probably identical with our recanescine. (Stoll, A., and Hofmann, A., J. Am, Chem. Soc, 1955, v77, 820.)

Alkaloids of apocynaceae IV. Dregamine, a new alkaloid fromVoacanga dregei E. M.

Dregamine, ein neues Alkaloid aus der ApocynaceaeVoacanga dregei E. M. wurde isoliert und charakterisiert. Diese Verbindung stellt einen neuen Vertreter der Klasse der 2-Acyl-indole dar.

The use of

The unique chemical and biological properties of β-lactam antibiotics and, in particular, the importance of penicillins and cephalosporins in the treatment of a variety of bacterial infections have stimulated investigations in various laboratories concerned with elucidation of the biosynthetic pathways leading to the formation of these antibiotics. Most of the present knowledge of some of these processes has been obtained from tracer studies involving 14C labelled precursors (Abraham & Newton 1967). The recent advances in the instrumentation required for recording 13C n.m.r.(c.m.r.) spectra, as well as commercial availability of simple 13C enriched compounds suitable for the synthesis of appropriate precursors, prompted us to examine the usefulness of c.m.r. spectroscopy in biosynthetic studies of cephalosporin C (Neuss, Nash, Lemke & Grutzner 1971).

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Hunterin wird als ein neues Alkaloid aus der Wurzelrinde vonHunteria eburnea Pichon beschrieben. Die analytischen und physikalischen Eigenschaften dieser Verbindung weisen darauf hin, dass Hunterin ein dimeres Alkaloid vom Indol-Indolin-Typus darstellt.

C n.m.r. (C.m.r.) Spectroscopy in Biosynthetic Studies Of

The presence of the oxygen atom in place of the sulfur atom has significant impact on the polarity of the β-lactam derivative. This has been illustrated by direct comparison of HPLC data of 4 different cephalosporin derivatives and their oxa analogues.

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[Me2-2H6]-D,L-valine has been synthesized and incorporated into penicillin V. The mass spectrum of the penicillin V methyl ester showed the retention of all six deuterons in the biosynthetic product.