Lipophilic free radical scavenger

Carvedilol is a highly lipophilic non-selective beta-adre-noceptor antagonist with alphai-blocking action, promoting peripheral vasodilatation. It also has free radical scavenging and antimitogenic effects. 

Presently, other captopril analogs, like zofenopril (a prodrug of which the cleavage of the thioester led the active compound zofenoprilat) are still marketed. They are able to coordinate Zn(II) and act as free radical scavenger. Their lipophilicity allows them to attain high lever in heart tissue and then they can be used as cardioprotective drugs (Figure 20.42). ... 

Another important application of oleic acid in the pharmaceutical field is in the production of fatty acid esters of vitamin C. These substances are natural antioxidants that could be used as adequate substitutes of synthetic ones, such as BHT (butylatedhidroxytoluene) and BHA (butylatedhidroxyanisole) (Karmee, 2009 Burham et al., 2009). They present an interesting lipophilicity, in distinction to vitamin C, and possess high free radical scavenging capacity. 

Antioxidants. Excessive concentrations of ROS can have serious effects on membranes, nucleic acid bases and proteins (Section 3.1.3). If uncontrolled, mutations and membrane damage could lead to cell death. To minimize damage, defensive control systems exist. Besides enzymes, there are hydrophilic- and lipophilic-soluble molecules called antioxidants , scavenging free radicals to prevent destruction of cellular biomolecules crucial for cell viability. Non-enzymatic biological antioxidants include tocopherols, carotenoids, qui-nones, bilirubin, steroids, ascorbate, uric acid, GSH, cysteine and metal-binding proteins, such as ferritin (Krinsky, 1992). 

Lapenna et al. (1998) found that ticlopidine, a thienopyridine characterised by lipophilic properties, at therapeutically relevant concentrations (2.5-10 pM), but neither aspirin nor salicylate, significantly counteracted copper-driven human LDL oxidation. Ticlopidine, at 5 and 10 pM, was also antioxidant on peroxyl radical-induced LDL oxidation yet it was ineffectual on thiol and ascorbate oxidation mediated by peroxyl radicals themselves, suggesting that drug antioxidant capacity is somehow related to the lipoprotein nature of the oxidiz-able substrate, but not to radical scavenging. The drug could not indeed react with the stable free radical l,l-diphenyl-2-picrylhydrazyl, not had apparent metal complexing-inactivating activity. 

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