Stereochemistry of caracurine V.

  title={Stereochemistry of caracurine V.},
  author={D. Zlotos},
  journal={Journal of natural products},
  volume={63 6},
  • D. Zlotos
  • Published 2000
  • Chemistry, Medicine
  • Journal of natural products
The 3D structure of the Strychnos alkaloid caracurine V was determined by means of NMR spectroscopy and semiempirical calculations. The previously unknown absolute configuration in the central eight-membered ring was assigned as (16R, 16'R, 17R, and 17'R). 
Strychnobaillonine, an unsymmetrical bisindole alkaloid with an unprecedented skeleton from Strychnos icaja roots.
A reinvestigation of the roots of Strychnos icaja resulted in the isolation of a new bisindole alkaloid named strychnobaillonine with original C-17-N-1' and C-23-C-17' junctions, which showed potent activity against the chloroquine-sensitive 3D7 strain of Plasmodium falciparum in vitro. Expand
6,7,14,15-Tetrahydro[1,5]diazocino[1,2-a:6,5-a′]diindole. Synthesis of a novel pentacyclic ring system
Abstract In search of new lead structures for potent allosteric enhancers of antagonist binding to muscarinic M 2 receptors, the first representative of a novel heterocyclic ring system,Expand
Bisquaternary caracurine V derivatives as allosteric modulators of ligand binding to M2 acetylcholine receptors.
Molecular modeling studies indicated that the caracurine V ring system satisfies the pharmacophore model for the allosteric interaction and suggests a sterically restricted binding pocket. Expand
Bisquaternary caracurine V and iso-caracurine V salts as ligands for the muscle type of nicotinic acetylcholine receptors: SAR and QSAR studies.
The binding constants and QSAR results revealed that the presence of hydrogen-bond acceptor groups close to the quaternary nitrogen, is detrimental for the nicotinic binding affinity, suggesting that it is possible to develop compounds with high muscarinic allosteric potency and low or negligible affinities for (alpha1)(2)beta1gammadelta nAChR. Expand
Semisynthetic Analogues of Toxiferine I and Their Pharmacological Properties at α7 nAChRs, Muscle-Type nAChRs, and the Allosteric Binding Site of Muscarinic M2 Receptors
All ligands showed a moderate to low antagonistic effect, suggesting that the alcoholic functions are not necessary for antagonistic action and should help delineate the structural requirements for activity at different types of AChRs and for the design of novel selective ligands. Expand
Evaluation of the impurity profile of alcuronium by means of capillary electrophoresis.
A HPLC method is described to limit the impurities of alcuronium, namely the diallylcaracurine (DAC) and the allyl-Wieland-Gumlich-aldehyde (WCA) to less than 0.1%; the limit of detection was found to be in the same range as found with HPLC. Expand
Allosteric site on muscarinic acetylcholine receptors: a single amino acid in transmembrane region 7 is critical to the subtype selectivities of caracurine V derivatives and alkane-bisammonium ligands.
These studies demonstrate that a stereochemical difference can be sufficient to translate into divergent epitope sensitivities and are the first time that the subtype selectivity of muscarinic allosteric agents has been completely accounted for by distinct receptor epitopes. Expand
Allosteric site on muscarinic acetylcholine receptors: identification of two amino acids in the muscarinic M2 receptor that account entirely for the M2/M5 subtype selectivities of some structurally diverse allosteric ligands in N-methylscopolamine-occupied receptors.
Two amino acids account entirely for the (approximately 100-fold) M2/M5 selectivity of the alkane-bisammonium and the caracurine V type allosteric ligands at NMS-free M2 receptors. Expand
Allosteric modulation of G protein-coupled receptors.
It appears that all three major classes of G protein-coupled receptors (A, B and C) are amenable to allosteric modulation by small molecules, which constitutes an attractive and novel means to identify new leads in the drug discovery process. Expand