Revision of the structure of ajmalimine.

Careful reexamination of the published 1H and 13C NMR spectral data of ajmalimine (1), an indole alkaloid from the roots of Rauvolfia serpentina, indicates that, in reality, the compound is (+)-17R-O-(3',4',5'-trimethoxybenzoyl)ajmaline (3).

p-Terphenyl- and phenanthraquinone derivatives: an NMR study.

(1)H- and (13)C-NMR spectral data are presented for six p-terphenylquinone derivatives (and for two monosubstituted quinones 1 and 2, used as model compounds) and for 9,10-phenanthraquinone and retenequinone. The chemical shifts were confirmed through correlation spectroscopy and NOE measurements.

Complete 1H- and 13C-NMR spectral data of piloquinone, a 9,10-phenanthrenequinone derivative from Streptomyces pilosus.

Complete (1)H- and (13)C-NMR spectral data of piloquinone are presented. The chemical shifts were confirmed through correlation spectroscopy and NOE measurements.

A 1H- and 13C-NMR study of seven ajmaline-type alkaloids.

1H- and 13C-NMR spectral data are presented for ajmaline (1), 17-O-acetylajmaline (2), isoajmaline (3), isosandwichine (4), rauflorine (5), vincamajine (6), and vincamedine (7). Some corrections to the previously reported assignments of compound 6 (1H-NMR) and compounds 3, 4 and 7 (13C-NMR) have been made. The 13C-NMR chemical shifts for rauflorine 5 are presented for the first time.

Total syntheses of 10-methoxydihydrocorynantheol and 10-methoxycorynantheidol.

10-Methoxydihydrocorynantheol and 10-methoxycorynantheidol were synthesized from 5-methoxytryptophol and 3-acetylpyridine. (13)C-NMR data of the prepared compounds and their synthetic intermediates are given.

Isolation of Catharanthus alkaloids by solid-phase extraction and semipreparative HPLC.

A combination of moderate-pressure chromatography on C18 sorbent and preparative HPLC is developed for rapid isolation of alkaloids from Catharanthus roseus. The procedure is optimized for vindoline and catharanthine with respective yields of 3 and 2 mg per 1 g of dried leaves of the plant. The methodology is also applied for identification of the above and other alkaloids from cultured plant cells.

Mass Spectral Evidence of the Occurrence of Vindoline in Heterotrophic Cultures of Catharanthus roseus Cells.

Vindoline concentrations in the leaves of 70 CATHARANTHUS ROSEUS of 3 cultivars were analyzed by HPLC, and 3 plants were selected for starting callus cultures on different media. When the initial calli were analyzed using a vindoline-specific RIA, the assay suggested a vindoline content of about 10 (-5)% dry weight for one-third of the first 60 cultures examined. Due to the unexpectedly high incidence of vindoline-positive calli, the screening programme was discontinued and efforts were concentrated on verifying the existence of this alkaloid in the cells.

Elaboration of the ethylidene side chain in the synthesis of indole alkaloids: preparation of (+/-)-deplancheine and its analogues.

A new method of elaborating the ethylidene side chain in the synthesis of (+/-)-deplancheine ( 1) and its analogues is described.

Indoloquinolizidines, formal derivatives of tetrahydro-beta-carbolines, show selective affinity for benzodiazepine, tryptamine and serotonin binding sites in rat brain.

Beta-carbolines and indoloquinolizidines occur in plants, and some of the former compounds also in mammalian tissues. Many beta-carbolines cause tremor or convulsions, and they are among the most potent known endogenous compounds to bind to benzodiazepine, tryptamine and serotonin binding sites. In this study seven indoloquinolizidines which are formal derivatives of 1,2-disubstituted 1,2,3,4-tetrahydro-beta-carbolines were assayed for their affinity for benzodiazepine, tryptamine and serotonin binding sites in rat brain in vitro.

An enzyme-linked immunosorbent assay for the antineoplastic agent vincristine.

An enzyme-linked immunosorbent assay for vincristine was developed, based on a new procedure for synthesizing the hapten-protein conjugate. In both the immunogen and the enzyme tracer a spacer group was introduced between the hapten and protein, and the vincristine was coupled at a site far from its functional groups. The antibody produced proved to be exceptionally specific as compared with previous immunoassays for bis-indole alkaloids.

Synthesis of Two Lactonic Amines Isolated During an Investigation of Garnieria spathulaefolia.

The formation of lactonic amines 3 and 4 from alpha-methylene-gamma-butyrolactone (tulipalin A) 1 is described.

A 400 MHz 1H-NMR Study of Seven Sarpagine-Type Alkaloids.

The chemical shifts and most of the main coupling constants of seven sarpagine alkaloids 1- 7 have been determined in a 400 MHz (1)H-NMR study.

[Monomeric Indole Alkaloids from Kopsia officinalis.].

Ten monomeric indole alkaloids have been identified from the roots of KOPSIA OFFICINALIS. Four of them are known: (-)-kopsinine 1, (+)-5,22-dioxokopsane 2, (-)-tetrahydroalstonine 4, and (-)-quebrachamine 3; and six are new: (-)-isoeburnamine 5 (enantiomer of the known alkaloid (+)-isoeburnamine), (-)-N-methoxycarbonyl-12-methoxykopsinaline 7, (-)-N-methoxycarbonyl-11,12-methylenedioxy kopsinaline 8, (-)-N-methoxycarbonyl-11,12-dimethoxykopsinaline 9, (-)-11,12-methylenedioxykopsinaline 10, and (-)-12-methoxykopsinaline 11.

Monomeric Indole Alkaloids from Ervatamia hainanensis.

Eleven monomeric indole alkaloids have been isolated from the roots of Ervatamia hainanensis. Nine of them are known: coronaridine 1, coronaridine hydroxyindolenine 2, heyneanine 3, vobasine 4, perivine 5, ibogamine 6, geissoschizol 7, 10-hydroxygeissoschizol 8 and 3-oxocoronaridine 9; and two are new: 10-hydroxyheyneanine 10 and 3-(beta-hydroxyethyl)-coronaridine 11.

Biogenesis of proteaceous alkaloids.

A scheme is presented which outlines the possible mode of biogenesis of alkaloids so far reported from the proteaceous plants Bellendena montana and Agastachys odorata (both from Tasmania), Darlingia darlingiana and D. ferruginea (from Queensland) and Knightia deplanchei and K. strobilina (from New Caledonia).