Synthesis and biological activities of new heterocyclic aromatic retinoids

Novel and selective imidazole-containing biphenyl inhibitors of protein farnesyltransferase

A series of imidazole-containing biphenyls was prepared and evaluated in vitro for inhibition of FTase and cellular Ras processing. Several of these analogues, such as 21, are potent inhibitors of FTase (<1nM), FTase/GGTase selective (>300-fold) and cellularly active (<or=80nM). An X-ray crystal structure of inhibitor 21 bound to rat farnesyltransferase is also presented.

Solution-phase synthesis of diaryl selenides using polymer-supported borohydride

[reaction: see text] A new series of selenium-containing diaryl retinoids have been prepared by a new direct nickel(II)-catalyzed coupling of a diselenide with an iodoaryl in the presence of polymer-supported borohydride.

Studies on structure-activity relationships of retinoic acid receptor ligands by means of molecular modeling

Vitamin A and its biologically active derivatives, retinal and retinoic acid, play an important role in vision, are required for reproduction, act as morphogenic agents during embryonic development, and regulate the growth and differentiation of a wide variety of cell types throughout the life of an organism. The biological action of retinoic acid and synthetic analogs, referred to as retinoids, is mediated by RAR alpha, RAR beta, or RAR gamma and/or by RXR alpha, RXR beta, or RXR gamma, all being nuclear receptors. Since retinoids exert profound effects on cell proliferation, differentiation, and apoptosis, these compounds seem to be promising agents for the treatment of cancer. Consequently, a large number of retinoids have been synthesized and examined to determine if they exert their biological activity according to retinoic acid receptor interaction. These screening methods are often expensive, time-consuming, and labor-intensive procedures. Since one can construct the pharmacophores of congeneric groups of drug molecules, molecular modeling techniques offer a new way to determine the binding abilities of different agents. We examined the structural properties of retinoids, which allow them to specifically bind to the different receptor subtypes. The thus-generated 3D pharmacophore models were used to predict the binding affinities of several retinoids to the retinoic receptor subtypes. Finally, the 3D models served as criteria for searching the Derwent World Drug Index for compounds that possess the features necessary for favorable ligand receptor interaction. The search resulted in a "hit list" containing 323 compounds, some of which are worth further investigation to determine if they act via retinoic acid receptor binding or not.