Solvent-free synthesis of novel steroidal 2-aminopyridines

Inhibition of protein misfolding and aggregation by steroidal quinoxalin-2(1H)-one and their molecular docking studies

A series of D-ring fused 16-substituted steroidal quinoxalin-2(1H)-one attached to an electron-releasing (ER) or electron-withdrawing (EW) groups via steroidal oxoacetate intermediate were synthesized to investigate their protein aggregation inhibition potential using human lysozyme (HLZ). The influence of the type of substituent at the C-6 positions of the quinoxalin-2(1H)-one ring on the protein aggregation inhibition potential was observed, showing that the EW moiety improved the protein aggregation inhibition potency. Of all the evaluated compounds, NO2-substituted quinoxalin-2(1H)-one derivative 13 was the most active compound and had a maximum protein aggregation inhibition effect. Significant stabilization effects strongly support the binding of the most biologically active steroidal quinoxalin-2(1H)-one with docking studies. The predicted physicochemical and ADME properties lie within a drug-like space which shows no violation of Lipinski's rule of five except compounds 12 and 13. Combined, our results suggest that D-ring fused 16-substituted steroidal quinoxalin-2(1H)-one has the potential to modulate the protein aggregation inhibition effect.

Synthesis, biological activities, and future perspectives of steroidal monocyclic pyridines

Steroidal pyridines are a class of compounds that have been the subject of extensive research in recent years due to their potential biological activities. The introduction of a pyridine ring into the steroid skeleton can significantly alter the chemical and biological properties of the compound, making it more potent and/or selective for a particular target. Different synthetic methods have been developed for the preparation of steroidal pyridines. This review provides an overview of the synthesis, biological activities, and future perspectives of steroidal monocyclic dihydropyridines, tetrahydropyridines, and pyridines from 2005 to the present. The different synthetic methods that have been developed for the preparation of these steroids are discussed, as well as the proposed mechanisms and the biological activities that have been reported. Finally, the potential of steroidal monocyclic pyridines for the development of new drugs is discussed. This review is intended to provide a comprehensive overview of the field of steroidal monocyclic pyridines for researchers and scientists who are interested in this area of research. It is also hoped that this review will stimulate further research into the synthesis and biological activities of steroidal pyridines to develop new and improved drugs for the treatment of diseases.

Recent advances on synthesis and biological activities of C-17 aza-heterocycle derived steroids

Steroids modification for improving their biological activities is one of the most efficient and fruitful methods to develop novel medicines. Steroids with aza-heterocycles attaching to the C-17 owing various biological activities have received great attentions and some of the compounds are developed successfully as drugs. In this review, the research of the syntheses and biological activities of steroids bearing various aza-heterocycles published in the last 8 years is assembled, and some important structure-activity relationships (SARs) of active compounds are presented. According to the analysis of the literatures and our experiences in this field, the potential of aza-heterocyclic steroids as medicinal drugs is proposed.

Synthesis and biological evaluation of 17-cyanopyridine derivatives of pregnenolone as potential anti-prostate cancer agents

A series of new 17-cyanopyridine derivatives of pregnenolone have been synthesized, and their anti-proliferative activities against different human cancer cell lines were tested. The extensive structure-activity relationship (SAR) data suggested that the introduction of 2-amino-4-aryl-3-cyanopyridine to the D ring of pregnenolone may increase the anti-cancer activity. Among the products, the most potent compound 4j exhibited good growth inhibition against all the tested cells especially for PC- 3 cells with an IC50 value of 2.0 μM. Further mechanistic studies showed that 4j inhibited the formation of cell colonies and migration, increased the level of reactive oxygen species (ROS) in PC-3 cells in a concentration-dependent manner, and induced necroptosis through the phosphorylation of receptor interacting protein 1/3 (P-RIP1/3) and phosphorylation of mixed lineage kinase domain-like protein (P-MLKL) pathway. The 17-pregnenolone cyanopyridine derivatives hold promising potential as anti-proliferative agents, and the most potent compound could be used as a starting point for the development of new steroidal heterocycles with improved anticancer potency and selectivity.

Screening and pharmacodynamic evaluation of the antirespiratory syncytial virus activity of steroidal pyridine compounds in vitro and in vivo

Respiratory syncytial virus (RSV) causes serious lower respiratory tract infections and there are currently no safer or more effective drugs available. It is important to find novel medications for RSV infection. A series of steroidal pyridines were synthesized for screening and evaluation of their antiviral activity and investigation of their antiviral mechanism of action. Compound 3l had the highest antiviral activity, with a half-maximal effective concentration (EC50 ) of 3.13 μM. Compound 3l was explored for its effects in vitro on RSV 2 h before infection (pretreatment), at the time of infection (competition), and 2 h after infection (postinfection). Toll-like receptor (TLR)-3, retinoic acid-inducible gene (RIG)-I, interleukin (IL)-6, and interferon (IFN)-β were suppressed at the cellular level. Mouse lung tissue was subjected to hematoxylin and eosin (HE) staining and immunohistochemistry, which showed that RSV antigen and M gene expression could be reduced by compound 3l. Decreased expression of TLR-3, RIG-I, IL-6, IFN-β, and IL-10 was also found in vivo. The results indicated that compound 3l exerted its antiviral effects mainly through inhibition of viral replication and downregulation of inflammatory factors.

Multi-Component One-Pot Assisted Synthesis, Anti-bacterial Capabilities, and Scanning Electron Microscopy of Novel Corticosteroid Thiopyran

BACKGROUND

Corticosteroids are an important group of polycyclic compounds having a wide range of pharmacological and physiological properties. Thiopyran derivatives are important building blocks of many biologically active compounds.

OBJECTIVE

Keeping in mind the wide range of applications of corticosteroids and thiopyran, herein we intend to develop a simple and efficient strategy to synthesize steroidal thiopyran derivatives starting with different commercially available corticosteroids and study their biological properties.

MATERIALS AND METHODS

To achieve our aim, we employed a one-pot multi-component synthesis of steroidal thiopyran derivatives by the reaction of corticosteroids, malononitrile, and carbon disulphide in the presence of triethylamine as a catalyst.

RESULTS AND DISCUSSION

An array of novel thiopyran compounds was obtained with the highest product yield using Et₃N. Scanning electron microscopy analysis manifested agglomeration pertaining to brick-shaped crystals of corticosteroid thiopyran. Synthesized compounds were also found to be active as anti-bacterial agents.

CONCLUSION

We describe a facile one-pot multi-component synthesis of corticosteroid thiopyran derivatives, which are found to possess anti-bacterial activity. Excellent yields of the products, simple work-up, easily available starting materials, and non-chromatographic purification are some of the main advantages of this protocol.

Design, synthesis and biological evaluation of new steroidal β-triazoly enones as potent antiproliferative agents

β-Triazoly enones are biologically interesting scaffolds, incorporation of such scaffolds into the steroid nucleus may generate new bioactive steroids and further enrich structural types of steroids. In this work, a series of new steroidal β-triazoly enones were synthesized based on click chemistry and Claisen-Schmidt condensation reaction and further evaluated for their antiproliferative activity against a panel of cancer cells. Most of these compounds showed better potency against PC-3 and MGC-803 cells. Particularly, compound 5a inhibited PC-3 and MGC-803 cells potently with the IC₅₀ values of 1.61 and 1.16 μM, respectively, and was less toxic toward GES-1 with an IC₅₀ value of 20.72 μM. Further mechanistic studies showed that compound 5a inhibited migration and invasion of MGC-803 and PC-3 dose-dependently. Treatment with compound 5a varied mRNA levels and protein expression of EMT markers in both cells. Collectively, the steroidal β-triazoly enones could be potentially utilized to develop new anticancer agents with the ability of inhibiting cell migration and invasion.