Design and synthesis of antioxidant alpha-lipoic acid hybrids

Effect of Curcumin and α-Lipoic Acid in Attenuating Weight Gain and Adiposity

Objective: Obesity is growing at epidemic proportions worldwide. Natural compounds curcumin and α-lipoic acid have been shown to reduce body-weight gain in both preclinical and clinical studies. This study examined the effect of a combination of curcumin and α-lipoic acid on weight gain and adiposity in high-fat-diet (HFD)-fed mice. Methods: C57BL6 mice (7 weeks old) were randomly assigned to receive either HFD (60% fat) or a normal diet (ND, 10% fat) for a 12-week period, following which the mice receiving HFD were further assigned to supplemental curcumin (0.07%), α-lipoic acid (0.2%), or a combination of curcumin and α-lipoic acid formulated into the HFD for a further 12 weeks. Food intake and body mass were determined on a weekly basis. Body fat composition was determined by dual energy X-ray absorptiometry. Results: Treatment with both curcumin and α-lipoic acid significantly reduced body weight gain in HFD-treated mice, and the combination was more effective in attenuating body weight compared to the individual agents. Food intake and caloric intake were significantly lower in the mice that received α-lipoic acid. Percentage body fat and fat mass and lean body mass, which were increased following HFD feeding, were attenuated in the mice receiving curcumin and the combination. Lean mass was also elevated in the mice that were subjected to an HFD, which was unaltered by curcumin or the combination. Conclusions: Taken together, the combination of curcumin and α-lipoic acid exhibits an additive effect in reducing weight gain and adiposity in response to high-fat feeding.

Molecular Consortia-Various Structural and Synthetic Concepts for More Effective Therapeutics Synthesis

The design and discovery of novel drug candidates are the initial and most probably the crucial steps in the drug development process. One of the tasks of medicinal chemistry is to produce new molecules that have a desired biological effect. However, even today the search for new pharmaceuticals is a very complicated process that is hard to rationalize. Literature provides many scientific reports on future prospects of design of potentially useful drugs. Many trends have been proposed for the design of new drugs containing different structures (dimers, heterodimers, heteromers, adducts, associates, complexes, biooligomers, dendrimers, dual-, bivalent-, multifunction drugs and codrugs, identical or non-identical twin drugs, mixed or combo drugs, supramolecular particles and various nanoindividuals. Recently much attention has been paid to different strategies of molecular hybridization. In this paper, various molecular combinations were described e.g., drug–drug or drug-non-drug combinations which are expressed in a schematic multi-factor form called a molecular matrix, consisting of four factors: association mode, connection method, and the number of elements and linkers. One of the most popular trends is to create small–small molecule combinations such as different hybrids, codrugs, drug–drug conjugates (DDCs) and small-large molecule combinations such as antibody-drug conjugates (ADCs), polymer-drug conjugates (PDCs) or different prodrugs and macromolecular therapeutics. A review of the structural possibilities of active framework combinations indicates that a wide range of potentially effective novel-type compounds can be formed. What is particularly important is that new therapeutics can be obtained in fast, efficient, and selective methods using current trends in chemical synthesis and the design of drugs such as the “Lego” concept or rational green approach.

Exploiting the lipoic acid structure in the search for novel multitarget ligands against Alzheimer's disease

Lipoic acid (LA) is a natural antioxidant. Its structure was previously combined with that of the acetylcholinesterase inhibitor tacrine to give lipocrine (1), a lead compound multitargeted against Alzheimer's disease (AD). Herein, we further explore LA as a privileged structure for developing multimodal compounds to investigate AD. First, we studied the effect of LA chirality by evaluating the cholinesterase profile of 1's enantiomers. Then, a new series of LA hybrids was designed and synthesized by combining racemic LA with motifs of other known anticholinesterase agents (rivastigmine and memoquin). This afforded 4, which represents a step forward in the search for balanced anticholinesterase and antioxidant capacities.