Studies on the interactions of 5-R-3-(2-pyridyl)-1,2,4-triazines with arynes: inverse demand aza-Diels-Alder reaction versus aryne-mediated domino process.

The interactions between substituted 5-R-3-(pyridyl-2)-1,2,4-triazines with in situ generated substituted aryne intermediates have been studied. The reaction afforded either inverse demand (ID) aza-Diels-Alder products or 1,2,4-triazine ring rearrangement (domino) products as major ones depending on the nature of both the substituents at the C5 position of the 1,2,4-triazine core or in the aryne moiety. The structures of the key products were confirmed based on X-ray data. Based on the density functional theoretical (DFT) studies of the Diels-Alder transition state geometries, the influence of the nature of arynes on the direction of the 1,2,4-triazine transformation has been proposed.

Discovery of a clinical stage multi-kinase inhibitor sodium (E)-2-{2-methoxy-5-[(2',4',6'-trimethoxystyrylsulfonyl)methyl]phenylamino}acetate (ON 01910.Na): synthesis, structure-activity relationship, and biological activity.

Cyclin D proteins are elevated in many cancer cells, and targeted deletion of cyclin D1 gene in the mammary tissues protects mice from breast cancer. Accordingly, there is an increasing awareness of this novel nonenzymatic target for cancer therapeutics. We have developed novel, nonalkylating styrylbenzylsulfones that induce cell death in wide variety of cancer cells without affecting the proliferation and survival of normal cells. The development of derivatized styrylbenzylsulfones followed logically from a tumor cell cytotoxicity screen performed in our laboratory that did not have an a priori target profile. Modifications of some of the precursor molecules led to lead optimization with regard to tumor cell cytotoxicity. In this report we describe the synthesis and structure-activity relationships of novel, nonalkylating (E)-styrylbenzylsulfones and the development of the novel anticancer agent sodium (E)-2-{2-methoxy-5-[(2',4',6'-trimethoxystyrylsulfonyl)methyl]phenylamino}acetate (ON 01910.Na), which is in phase III trials for myelodysplastic syndromes (MDS) associated with aberrant expression of cyclin D proteins.

Novel coumarin-3-(N-aryl)carboxamides arrest breast cancer cell growth by inhibiting ErbB-2 and ERK1.

A series of novel coumarin carboxamides were synthesized, and their tumor cell cytotoxic activity was investigated. These compounds specifically inhibited the growth of cancer cells that have a high level of ErbB-2 expression. Immunoprecipitation analysis of the cell lysates prepared from carboxamide treated cancer cells showed the inhibition of ErbB-2 phosphorylation suggesting the interaction of these compounds with ErbB-2 receptor. The down regulation of the kinase activity was further confirmed by performing in vitro kinase assay with recombinant ErbB-2 incubated with carboxamides. The inhibition of ErbB-2 phosphorylation correlated with down-regulation of ERK1 MAP kinase activation that is involved in proliferative signaling pathway. Furthermore, the cell-killing activity of many of these inhibitors is restricted to tumor cells with no demonstrable cytotoxicity against normal human fibroblasts suggesting that these compounds are tumor-specific.

Design, synthesis, and biological evaluation of (E)- and (Z)-styryl-2-acetoxyphenyl sulfides and sulfones as cyclooxygenase-2 inhibitors.

A new series of styryl acetoxyphenyl sulfides and sulfones possessing (E)- and (Z)-configurations were designed and prepared by stereospecific syntheses. All these compounds were evaluated for their ability to inhibit COX-2 enzyme in vitro. Structure-activity relationship studies on these compounds revealed that only sulfides with (Z)-configuration have potential COX-2 inhibitory activity. This inactivation of the enzyme is believed to be due to the selective covalent modification of COX-2 by the inhibitors.