Exploration of the effects of "minor" structural differences on the antitumor activity and toxicity of dimeric Catharanthus alkaloids resulted in the preparation of deacetylvinblastine amide (vindesine, VDS) from either vinblastine (VLB) or deacetylvinblastine. Adequate amounts of vindesine for biological testing were prepared by preferential hydrazinolysis of the C23-ester in the vindoline moiety of VLB, followed by hydrogenolysis of the resulting deacetylvinblastine hydrazide. Vindesine in its activity spectrum against rodent tumor systems resembles vincristine (VCR) rather than its parent VLB, while its neurotoxic potential appears to be less than that of VCR. The experimental models developed to estimate this potential include in vitro measurements of axoplasmic transport effects in the cat sciatic nerve and the estimation of neuromuscular disturbances in chickens and monkeys by vindesine in comparison with VCR. A radioimmunoassay for VLB, VCR, and VDS, developed by means of deacetylvinblastine acid azide, has been used to study the pharmacokinetics of vindesine in man. The clinical investigation of vindesine is in progress. Deacetylvinblastine, in contrast to earlier reports, showed activity against several murine tumor systems.
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http://dx.doi.org/10.1021/jm00199a016 | DOI Listing |
Plant Cell Environ
December 2024
Department of Plant and Soil Sciences and Kentucky Tobacco Research and Development Center, University of Kentucky, Lexington, Kentucky, USA.
The evolutionary arms race between plants and insects has led to key adaptive innovations that drive diversification. Alkaloids are well-documented anti-herbivory compounds in plant chemical defences, but how these specialized metabolites are allocated to cope with both biotic and abiotic stresses concomitantly is largely unknown. To examine how plants prioritize their metabolic resources responding to herbivory and cold, we integrated dietary toxicity bioassay in insects with co-expression analysis, hierarchical clustering, promoter assay, and protein-protein interaction in plants.
View Article and Find Full Text PDFJ Nat Med
March 2024
Faculty of Pharmaceutical Sciences, Hoshi University, Ebara 2-4-41 Shinagawa-Ku, Tokyo, 142-8501, Japan.
J Nat Med
January 2024
Faculty of Pharmaceutical Sciences, Hoshi University, Ebara 2-4-41, Shinagawa-ku, Tokyo, 142-8501, Japan.
A dimeric indole alkaloid, isovincathicine consisting of an aspidosperma type and modified iboga with C-7-C-20 connection type skeletons was first isolated from Catharanthus roseus, and the structure including stereochemistry was elucidated on the basis of spectroscopic data as well as DP4 statistical analysis. Isovincathicine inhibited cell proliferation in A549 cells. We investigated the detailed mode of action of isovincathicine-induced inhibitory effects on cell proliferation in A549 cells.
View Article and Find Full Text PDFJ Pharm Biomed Anal
October 2023
Department of Plant Physiology and Metabolomics, Agricultural Institute, Centre for Agricultural Research, ELKH, Brunszvik u. 2., Martonvásár 2462, Hungary. Electronic address:
Methods Mol Biol
June 2022
Molecular Plant Biology and Biotechnology Lab, CSIR-Central Institute of Medicinal and Aromatic Plants, Research Centre, Bengaluru, India.
Madagascar periwinkle (Catharanthus roseus, family Apocynaceae) is a reservoir of more than 130 monoterpene indole alkaloids (MIAs) including the famous anti-neoplastic dimeric MIAs vinblastine and vincristine, and anti-hypertensive monomeric MIAs ajmalicine and serpentine. Understanding the biosynthetic steps and regulatory factors leading to the formation of MIAs is crucial for rational engineering to achieve targeted enhancement of different MIAs. Due to its highly recalcitrant nature, C.
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