title: Isoxazole-type derivatives related to combretastatin A-4, synthesis and biological evaluation.
abstract: Novel combretastatin analogues bearing various five-membered heterocycles with consecutive oxygen and nitrogen atoms, in place of the olefinic bridge of CA4, have been synthesized (isoxazole, isoxazoline, oxadiazole, etc). These compounds have been evaluated for cytotoxicity and their ability to inhibit the tubulin assembly. On the basis of the relative position of the aromatic A- and B-rings on the heterocyclic moiety, they could be split in two classes, the alpha,gamma- or alpha,beta-diaryl heterocyclic derivatives. In the first series, the 3,5-diaryloxadiazole 9a displayed comparable antitubulin activity to that of CA4, but was devoid of cytotoxic effects. Among the alpha,beta-diaryl heterocyclic derivatives, the 4,5-diarylisoxazole 35 exhibited greater antitubulin activity than that of CA4 (0.75 vs 1.2 microM), but modest antiproliferative activity. These data showed that minor alteration in the chemical structure of the heterocyclic ring and its relative orientation with regard to the two phenyl rings of CA4 could dramatically influence the tubulin binding properties.
authors.affiliation: CNRS, UMR 176, Institut Curie, Centre de Recherche, 26 rue d'Ulm, 75248 Paris cedex 05, France.
authors.forename: Julia
authors.initials: J
authors.lastname: Kaffy
authors.forename: Renée
authors.initials: R
authors.lastname: Pontikis
authors.forename: Danièle
authors.initials: D
authors.lastname: Carrez
authors.forename: Alain
authors.initials: A
authors.lastname: Croisy
authors.forename: Claude
authors.initials: C
authors.lastname: Monneret
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Florent
mesh_terms: D001921:Brain; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004353:Drug Evaluation, Preclinical; D006801:Humans; D007555:Isoxazoles / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D015394:Molecular Structure; D011485:Protein Binding; D013237:Stereoisomerism; D013267:Stilbenes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D013329:Structure-Activity Relationship; D014404:Tubulin / Q000187:drug effects / Q000378:metabolism
chemical_list: D007555:Isoxazoles; D013267:Stilbenes; D014404:Tubulin; C058728:fosbretabulin