Small diverse antioxidant functionalities for oxidative stress disease drug discovery.

There is an up-surge of interest in antioxidants because of their potential use in mitigating a wide array of oxidative stress mediated diseases. In the course of our literature search for diverse functional groups, with utility in the design of potential drugs for preventing oxidative stress related cell injury, we have collected a small literature library of core structures or moieties possessing antioxidant activities. These functional groups can be re-configured into robust antioxidants drug molecules, in their own right, or incorporated into drug structures where the antioxidant capability is required. The lack of single papers presenting a collection of diverse small molecule antioxidant moieties as potential design leads prompted us to write this short review of twenty five such functionalities.

Design, synthesis, and evaluation of metabolism-based analogues of haloperidol incapable of forming MPP+-like species.

The long-term, irreversible, Parkinsonism-like side effects of haloperidol have been speculated to involve several mechanisms. More recently, it has been speculated that the metabolic transformation to MPP+-like species may contribute to the Parkinsonism-like side effects. Because BCPP+ and its reduced analogue have been shown to possess the potential to destroy dopamine receptors in the nigrostriatum, we have designed new analogues of haloperidol lacking the structural features necessary to form neurotoxic quaternary species but retaining their dopamine-binding capacity. The most potent agent at the D2 receptor, the homopiperidine analogue 11, was found to be equipotent to haloperidol. It was also of interest to identify analogues with DA binding profiles similar to that of clozapine at the dopamine receptor subtypes. Evaluation of the proposed agents shows that the ratio of D2 to D4 (2) binding of clozapine was mimicked by 7 [K(i)(D2) = 33, K(i)(D3) = 200, K(i)(D4) = 11 nM; K(i)(D2)/K(i)(D4) = 3] and 9 [K(i)(D2) = 44, K(i)(D3) = 170, K(i)(D4) = 24 nM; K(i)(D2)/K(i)(D4) = 2]. A preliminary in-vivo testing of compound 7 shows that its behavioral profile is similar to that of clozapine. This profile suggests that there is a need for further evaluation of these two synthetic agents and their enantiomers for efficacy and lack of catalepsy in animal models.