NF-κB is a ubiquitous and well-characterised protein responsible for the regulation of complex phenomena, with a pivotal role in controlling cell signalling in the body under certain physiological and pathological conditions. Among other functions, NF-κB controls the expression of genes encoding the pro-inflammatory cytokines (e. g., IL-1, IL- 2, IL-6, TNF-α, etc.), chemokines (e. g., IL-8, MIP-1α, MCP1, RANTES, eotaxin, etc.), adhesion molecules (e. g., ICAM, VCAM, E-selectin), inducible enzymes (COX-2 and iNOS), growth factors, some of the acute phase proteins, and immune receptors, all of which play critical roles in controlling most inflammatory processes. Since NF-κB represents an important and very attractive therapeutic target for drugs to treat many inflammatory diseases, including arthritis, asthma, and the auto-immune diseases, most attention has been paid in the last decade to the identification of compounds that selectively interfere with this pathway. Recently, a great number of plant-derived substances have been evaluated as possible inhibitors of the NF-κB pathway. These include a wide range of compound classess, such as lignans (manassantins, (+)-saucernetin, (-)-saucerneol methyl ether), sesquiterpenes (costunolide, parthenolide, celastrol, celaphanol A), diterpenes (excisanin, kamebakaurin), triterpenes (avicin, oleandrin), polyphenols (resveratrol, epigallocatechin gallate, quercetin), etc. In this mini-review we will discuss the medicinal chemistry of these compounds with regards to the NF-κB inhibition.

Tubulin protein is a major target for anticancer drug discovery. As a result, antimitotic agents constitute an important class of the current anticancer drugs. Hundreds of tubulin inhibitors, naturally occurring, semisynthetic or synthetic, have been reported. Among these, combretastatin A-4 (CA-4), isolated from a South African tree Combretum caffrum, is one of the most potent antimitotic agents. CA-4 shows strong cytotoxicity against a variety of cancer cells, including multi-drug resistant cancer cell lines. It has also been demonstrated to exert highly selective effects in proliferating endothelial cells. CA-4 disodium phosphate (CA4DP), a water-soluble prodrug of CA- 4, shows potent antivascular and antitumor effects in a wide variety of preclinical tumor models. Consequently, a number of CA-4 analogues has been synthesized and evaluated. In this paper, the structure-activity relationships and pharmacological properties of the CA-4 derivatives as a class of potent antimitotic anticancer agents are reviewed and discussed.

The call for the discovery of less toxic, more selective, and more effective agents to treat cancer has become more urgent. Inhibition of angiogenesis continues to be one of the main streams in the current cancer drug discovery activity. Insights into tumor angiogenesis biology have led to the identification of a number of molecules, which are important for the progression of these processes. Of particular interest is a group of growth factors including fibroblast growth factor, platelet-derived growth factor, and vascular endothelial growth factor. These growth factors and their corresponding receptor tyrosine kinases have become important targets for inhibition of the proliferation of endothelial cells, the main component of blood vessels. The validated targets for inhibition of angiogenesis also include a family of matrix metalloproteinases and cell adhesion molecules. In the closely related area, protein kinases have emerged as one of the most important targets for drug discovery. Besides growth factor receptor tyrosine kinases, numerous other protein kinases implicated in malignancies have been identified including non-receptor kinases such as Bcl-Abl and Src kinases. In addition, the cell cycle regulators (cyclin-dependent kinases, p21 gene) and apoptosis modulators (Bcl-2 oncoprotein, p53 tumor suppressor gene, survivin protein, etc) have also attracted renewed interest as potential targets for anticancer drug discovery. Other molecular targets include protein farnesyltransferase (FTase), histone deacetylase (HDAC), and telomerase, which have essential roles in cellular signal transduction pathways (FTase, HDAC) and cell life-span (telomerase). This review presents a comprehensive summary and discussion on the most important targets currently attracting a great deal of interest in contemporary anticancer drug design and discovery. Recent advances complementing these targets are also highlighted.

To screen Vietnamese medicinal plants for xanthine oxidase (XO) inhibitory activity and to isolate XO inhibitor(s) from the most active plant. The plants materials were extracted by methanol. The active plant materials were fractionated using different organic solvents, including n-hexane, ethyl acetate, and n-butanol. Bioassay-guided fractionation and column chromatography were used to isolate compounds. The compounds structures were elucidated by analysis of spectroscopic data, including IR, MS, and NMR. Three hundreds and eleven methanol extracts (CME) belonging to 301 Vietnamese herbs were screened for XO inhibitory activity. Among these plants, 57 extracts displayed XO inhibitory activity at 100 μg/mL with inhibition rates of over 50%. The extracts of Archidendron clypearia (A. clypearia), Smilax poilanei, Linociera ramiflora and Passiflora foetida exhibited the greatest potency with IC50 values below 30 μg/mL. Chemical study performed on the extract of A. clypearia resulted in the isolation of six compounds, including 1-octacosanol, docosenoic acid, daucosterol, methyl gallate, quercitrin and (-)-7-O-galloyltricetiflavan. The compound (-)-7-O-galloyltricetiflavan showed the most potent XO inhibitory activity with an IC50 value of 25.5 μmol/L. From this investigation, four Vietnamese medicinal plants were identified to have XO inhibitory effects with IC50 values of the methanol extracts below 30 μg/mL. Compound (-)-7-O- galloyltricetiflavan was identified as an XO inhibitor from A. clypearia with IC50 value of 25.5 μmol/L.