Current Topics in Medicinal Chemistry - Volume 22, Issue 23, 2022

High costs and risks are common issues in traditional drug research and development. Usually, it takes a long time to research and develop a drug, the effects of which are limited to relatively few targets. At present, studies are aiming to identify unknown new uses for existing drugs. Drug repositioning enables drugs to be quickly launched into clinical practice at a low cost because they have undergone clinical safety testing during the development process, which can greatly reduce costs and the risks of failed development. In addition to existing drugs with known indications, drugs that were shelved because of clinical trial failure can also be options for repositioning. In fact, many widely used drugs are identified via drug repositioning at present. This article reviews some popular research areas in the field of drug repositioning and briefly introduces the advantages and disadvantages of these methods, aiming to provide useful insights into future development in this field.

Bacopa monnieri (BM) is of immense therapeutic potential in today’s world. This review is aimed to project the beneficial role of BM in disorders affecting the brain, including Alzheimer’s disease, Parkinson’s disease, stroke, epilepsy, and depression. The active constituents and metabolites responsible for the effects of BM could be bacoside A and B, bacopaside I and II, bacopasaponin C, betulinic acid, asiatic acid, loliolide, ebelin lactone, and quercetin. The mechanistic role of BM in brain disorders might be related to its ability to modulate neurotransmission, neurogenesis, neuronal/ glial plasticity, intracellular signaling, epigenetics, cerebral blood flow, energy metabolism, protein folding, endoplasmic reticulum stress, neuroendocrine system, oxidative stress, inflammation, and apoptosis. We have also discussed CDRI-08, clinical trials, safety, emerging formulation technologies, as well as BM combinations, and dietary supplements. To propel the clinical translation of BM in disorders affecting the brain, strategies to improve brain delivery via novel formulations and integration of the preclinical findings into large and well-defined clinical trials, in appropriate age groups and sex, specifically in the patient population against existing medications as well as placebo, are essentially required.

Xanthones (9H xanthen-9-one) are an important class of heterocyclic compounds containing oxygen and a moiety of gamma-pirone, dense with a two-benzene ring structure, distributed widely in nature. Naturally occurring xanthones are found in micro-organisms and higher plants as secondary metabolites in fungi and lichens. Compounds of the family Caryophyllaceae, Guttiferae and Gentianaceae, are the most common natural source of xanthones. The structure of the xanthones nucleus, coupled with its biogenetic source, imposes that the carbons are numbered according to the biosynthetic pact. The characteristics oxygenation pattern of xanthones earlier is mixed shikimateacetate biogenesis. The major class of xanthones includes simple oxygenated, non-oxygenated, xanthonolignoids, bisxanthones, prenylated and related xanthones, miscellaneous xanthones. Their great pharmacological importance and interesting scaffolds were highly encouraged by scientists to investigate either the synthesis design or natural products for cancer treatment. Because currently used antitumor drugs possess high toxicity and low selectivity, efficacious treatment may be compromised. This review is limited to the antitumor activity of xanthones and the chemistry of xanthone core, which may help provide fundamental knowledge to the medicinal chemist for new and advanced research in drug development.

Parthenium hysterophorus L. belonging to the family Asteraceae is a noxious weed infestation with allelopathic effects with its lower economic value. It poses a serious risk to its surroundings. The presence of oils, polyphenols, flavones, flavonoids, alkaloids, terpenes, pseudoguaianolides, and histamines in P. hysterophorus makes it important and beneficial due to its medicinal properties. This review article is focused on the history, geographical distribution, chemical composition, and molecular structure of some phytochemicals and ethanopharmacological aspects of P. hysterophorus. The harmful effects of this weed have also been included. The information available from the existing literature revealed that P. hysterophorus is rich in various phytochemicals with different pharmacological activities. However, the complete analysis of different phytoconstituents isolated from P. hysterophorus and their specific properties are not fully understood. The sporadic information published in some journals suggests that this plant could be exploited to develop new drugs against certain diseases, including cancer, HIV-1 infection, and immunological disorders. The structure and mode of action of some compounds such as parthenin and stigmasterol were also discussed. Though the current information on P. hysterophorus indicates the ethnopharmacological implications of extracts of this plant, more systematic and extensive studies are still required to properly understand the contribution of its specific chemical constituents responsible for their various medicinal properties.

Aims: The aim of this study was to simultaneously enhance the solubility and stability of bacogenins hydrolyzed bacoside rich extract by a ternary system comprised of hydrogenated soy lecithin and a third auxiliary substance, fulvic acid. Methods: Both ternary and binary complexes were prepared using the solvent evaporation method were characterized by Fourier transform infrared technique, differential scanning calorimeter and scanning electron microscope. The entrapment efficacy in both binary and ternary system was calculated and the effect on the solubility, dissolution and stability of bacogenins was found out. Furthermore, the prepared complexes were subjected to behavioural pharmacological studies. Results: FTIR, DSC, and SEM studies in totality confirmed the formation of binary and ternary complexes. Enhancement in solubility was observed, and the order of release characteristics was found to be BHFS> BHSL>BHF> BH when the dissolution studies were carried out in 40% aqueous solution of ethanol. A significant improvement in the memory and antioxidant capacity was noticed in both binary, ternary complexes and fulvic acid treatment groups. Conclusion: The results revealed that the ternary complex could be a promising drug delivery system to improve the oral bioavailability of the bacogenins.