When microtubules in animal cells are dissociated and then allowed to recover, they re-grow from discrete points in the cytoplasm known as microtubule-organizing centres (MTOC). The microtubules may be dissociated by antimitotic drugs such as colcemid, vinblastine and griseofulvin, or by chilling the cells. Immunofluorescence studies show that the number of MTOC seen does not depend on the conc...

In studies on the antiproliferative actions of coumarin compounds, we discovered that dicoumarol (a coumarin anticoagulant; 3,3'-methylenebis[4-hydroxycoumarin]) inhibits the first cleavage of Strongylocentrotus purpuratus (sea urchin) embryos in a concentration-dependent manner with 50% inhibition occurring at a concentration of 10 microM. Because first cleavage in sea urchin embryos is highly...

Taxanes are very effective at causing mitotic arrest; however, there is variability among cancer cells in the apoptotic response to mitotic arrest. The variability in clinical efficacy of taxane-based therapy is likely a reflection of this variability in apoptotic response, thus elucidation of the molecular mechanism of the apoptotic response to mitotic stress could lead to improved clinical st...

Formation of the C11-C1' bond through application of Barton's radical decarboxylation and quinone addition is the cornerstone of a new convergent and concise synthesis of the marine metabolites avarol (1) and avarone (2; see scheme), for which antimitotic, antileukemic, and antiviral effects have been reported.

There has been considerable controversy about the action of heparin on mitosis. Early workers in tissue culture routinely used heparizined plasma without apparent inhibition of growth (2). Later, however, several investigators reported that hepa rin inhibited mitosis either in vitro or in vivo (1, 4, 5, 15), although others found it was not in hibitory (8, 10, 14). A search is being made in our...

Three new bicyclic peptides, celogentins A (1), B (2), and C (3), have been isolated together with a known-related peptide, moroidin (4), from the seeds of Celosia argentea, and their structures including absolute stereochemistry were determined by using extensive NMR methods and chemical means. Celogentins A (1), B (2), and C (3) inhibited the polymerization of tubulin, and celogentin C (3) wa...

Ustiloxins A (1a), B (1b), C (1c), D (1d) and E (1e), antimitotic peptides, have been isolated from the water extract of false smut balls caused on the panicles of rice plant by a fungus Ustilaginoidea virens. The structure of 1b was assigned from its spectral property and its amino acid analysis in relation to 1a whose structure was determined previously by a combination of X-ray crystallograp...

medicinal chemistry depends on many other disciplines ranging from organic chemistry andpharmacology to computational chemistry. typically medicinal chemists use the moststraightforward ways to prepare compounds. the validation of any design project comes from thebiological testing.studies of the binding site of vinblastine by a single cross—linking experiment identified it asbeing between resi...

Vinca alkaloids and its derivatives like Vincristine, Vinblastine etc. isolated from Catharanthus roseus plants are widely used in the treatment of various types cancers. Mode action (vinblastine, vincristine, vinorelbine) is microtubule-stabilizing agents (MTAs) i.e., arrest cell cycle via disrupting microtubule dynamics. Vincristine major side effect neurotoxicity. Hoverer, induce neuropathy ...