Synthesis and bioactivities of novel 4,5,6,7-tetrahydrothieno[2,3-c]pyridines as inhibitors of tumor necrosis factor-alpha (TNF-alpha) production

Synthesis and evaluation of new 2-aminothiophenes against Mycobacterium tuberculosis

Tuberculosis (TB) and its drug resistant forms kills more people than any other infectious disease. This fact emphasizes the need to identify new drugs to treat TB. 2-Aminothiophenes (2AT) have been reported to inhibit Pks13, a validated anti-TB drug target. We synthesized a library of 42 2AT compounds. Among these, compound 33 showed remarkable potency against Mycobacterium tuberculosis (Mtb) H37RV (MIC = 0.23 μM) and showed an impressive potency (MIC = 0.20-0.44 μM) against Mtb strains resistant to isoniazid, rifampicin and fluoroquinolones. The site of action for the compound 33 is presumed to be Pks13 or an earlier enzyme in the mycolic acid biosynthetic pathway. This inference is based on structural similarity of the compound 33 with known Pks13 inhibitors, which is corroborated by mycolic acid biosynthesis studies showing that the compound strongly inhibits the biosynthesis of all forms of mycolic acid in Mtb. In summary, these studies suggest 33 represents a promising anti-TB lead that exhibits activity well below toxicity to human monocytic cells.

Anti-arthritic agents: progress and potential

Osteoarthritis and rheumatoid arthritis are the two most common types of arthritis. Cartilage breakdown is a key feature of both diseases which contributes to the pain and joint deformity experienced by patients. Therefore, anti-arthritis drugs are of great importance. The aim of this review is to present recent progress in studies of various agents against osteoarthritis and rheumatoid arthritis. The structures and activities of anti-arthritic agents, which used in medical practice or are in development, are presented and discussed. The effects and mechanisms of action of opioids, glucocorticoids, non-steroidal anti-inflammatory drugs, disease-modifying anti-rheumatic drugs, natural products derived from plants, nutraceuticals, and a number of new and perspective agents are considered. Various perspective targets for the treatment of osteoarthritis and rheumatoid arthritis are also discussed. Trials of good quality are needed to draw solid conclusions regarding efficacy of many of the studied agents. Unfortunately, to date, there is no pharmacologic agent proven to prevent the progression of both diseases, and there is an urgent need for further development of better anti-arthritic agents.

QSAR and docking studies on capsazepine derivatives for immunomodulatory and anti-inflammatory activity

Capsazepine, an antagonist of capsaicin, is discovered by the structure and activity relationship. In previous studies it has been found that capsazepine has potency for immunomodulation and anti-inflammatory activity and emerging as a favourable target in quest for efficacious and safe anti-inflammatory drug. Thus, a 2D quantitative structural activity relationship (QSAR) model against target tumor necrosis factor-α (TNF-α) was developed using multiple linear regression method (MLR) with good internal prediction (r2 = 0.8779) and external prediction (r2pred = 0.5865) using Discovery Studio v3.5 (Accelrys, USA). The predicted activity was further validated by in vitro experiment. Capsazepine was tested in lipopolysaccharide (LPS) induced inflammation in peritoneal mouse macrophages. Anti-inflammatory profile of capsazepine was assessed by its potency to inhibit the production of inflammatory mediator TNF-α. The in vitro experiment indicated that capsazepine is an efficient anti-inflammatory agent. Since, the developed QSAR model showed significant correlations between chemical structure and anti-inflammatory activity, it was successfully applied in the screening of forty-four virtual derivatives of capsazepine, which finally afforded six potent derivatives, CPZ-29, CPZ-30, CPZ-33, CPZ-34, CPZ-35 and CPZ-36. To gain more insights into the molecular mechanism of action of capsazepine and its derivatives, molecular docking and in silico absorption, distribution, metabolism, excretion and toxicity (ADMET) studies were performed. The results of QSAR, molecular docking, in silico ADMET screening and in vitro experimental studies provide guideline and mechanistic scope for the identification of more potent anti-inflammatory & immunomodulatory drug.

The Gewald multicomponent reaction

The Gewald reaction of sulfur, cyanoacetic acid derivatives, and oxo-component (G-3CR) yielding highly substituted 2-aminothiophene derivatives has seen diverse applications in combinatorial and medicinal chemistry. Its products are of great use in pharmaceutical industry mainly as small molecular weight inhibitors. We herein review synthetic scope and variations, usage, and structural biology of Gewald products.

Potential new drugs for therapy of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease is a major health problem with cigarette smoking as its major risk factor. Current therapies are directed against the symptoms (e.g., breathlessness and mucus production) or the chronic airway inflammation. However, the excessive annual decline in lung function and the airway inflammation have not yet been shown to be improved by these strategies. New potential drug therapies are directed against specific components of the inflammation. Novel drugs have been developed for treatment of inflammatory diseases including chronic obstructive pulmonary disease in order to antagonise cytokines and chemokines such as TNF-alpha, CXC chemokine ligand 8 (IL-8) or CC chemokine ligand 2 (monocyte chemoattractant protein 1) that orchestrate the inflammatory process. Some of these drugs are shown to be effective in patients with other chronic inflammatory diseases but still have to prove their efficacy in the treatment of chronic obstructive pulmonary disease.

Lead compounds discovered from libraries: part 2

Many lead compounds with the potential to progress to viable drug candidates have been identified from libraries during the past two years. There are two key strategies most often employed to find leads from libraries: first, high-throughput biological screening of corporate compound collections; and second, synthesis and screening of project-directed libraries (i.e. target-based libraries). Numerous success stories, including the discovery of several clinical candidates, testify to the utility of chemical library collections as proven sources of new leads for drug development.

Synthesis and bioactivities of novel bicyclic thiophenes and 4,5,6,7-tetrahydrothieno[2,3-c]pyridines as inhibitors of tumor necrosis factor-alpha (TNF-alpha) production

We synthesized bicyclic thiophenes and 4,5,6,7-tetrahydrothieno[2,3-c]pyridine derivatives, and evaluated for their ability to inhibit LPS-stimulated production of TNF-alpha. Several compounds revealed excellent in vivo activity. Furthermore, an effective compound was found in adjuvant-induced arthritic model (AIA) of rat.