Mini Reviews in Medicinal Chemistry - Volume 20, Issue 3, 2020

In today’s world, metabolic disorders are much dominant, and among them, diabetes is causing the highest rate of mortality. There is no cure for diabetes, while treatment could be done either by insulin therapy or oral antidiabetic drug. Oral antidiabetic agents target pathogenic factors like receptors, enzymes, genes and proteins involved in diabetes progression. Among them, recently, sodium-glucose co-transporters (SGLTs) have been recognized for their potential to effectively treat Type 2 diabetes mellitus. SGLTs are classified as SGLT-1 and SGLT-2, and among them, SGLT-2 is a major transporter which is involved in glucose reabsorption. Therefore, targeting SGLTs by its inhibitors could be a better choice to control the blood glucose level. Canagliflozin, dapagliflozin, empagliflozin, ipragliflozin, luseogliflozin, and tofogliflozin are known to be SGLT-2 inhibitors. Herein, we discussed the current and future aspects of the development and applications of SGLT-2 inhibitors.

The ubiquitous occurrence of Antimicrobial Peptides (AMPs) in all domains of life emphasizes their crucial role as ancient mediators of host defense. Despite their antiquity and prolonged history of exposure to pathogens, endogenous AMPs continue to serve as effective antibiotics. An "evolutionary arms race" between host and pathogen resulted in structural diversity of AMPs, leading these molecules to retain activity against a wide range of pathogens, including antibiotic-resistant microbes. As the menace of antibiotic resistance continues to render most antibiotics ineffective against pathogens, the search for novel drug candidates has taken the center stage. The ability of AMPs to combat antibiotic-resistant microbes gave rise to a remarkable surge of interest in AMPs as potential therapeutics. Apart from being effective antimicrobials, AMPs have also found application as probes suitable for in-situ diagnosis of infection. Here, we review the evolutionary history of AMPs, their structural diversity, and mechanism of interaction with microbial membranes. We also summarize the role of AMPs as modern pharmaceuticals and challenges to this development.

Cinnoline or Benzo-pyridazine has its place in the family of fairly well-known benzfuseddiazine heterocycles. Because of its natural occurrence and synthetic exploration, cinnoline compounds validated its thought-provoking bioactivity through a number of research publications and patents during last few decades. A creative consideration has been rewarded to the synthesis of cinnoline based heterocyclic compounds, mostly due to their wide range of diverse pharmacological activities. The present review covers the principle approaches to the synthesis of cinnoline nucleus and almost all biological properties of 115 cinnoline derivatives reported during the last 65 years from natural and synthetic origin with 140 references.

Global Human Immunodeficiency Virus (HIV) statistics by the World Health Organization (WHO) for the year 2017 was estimated to be 36.9 (31.1-43.9) million. Antiviral drug resistance poses a serious threat to public health and requires immediate action. Retroviral Integrase (IN), a component enzyme in the retroviral pre-integration complex (PIC) enables a retrovirus to incorporate its genetic material into the host DNA. Development of resistance by the current integrases invites immediate attention of the drug discovery community for the development of new second-generation Integrase Strand Transfer Inhibitors (INSTIs). It will exhibit greater efficacy against Elvitegravir (EVG) and Raltegravir (RAL) resistant strains of HIV. This review focuses on the mechanism, importance of integrase structure, function and current research on small molecule inhibitors of integrase to overcome drug resistance. The molecular mechanism of retroviral integrase inhibition and the evolution of resistance are also explored.

Arsenic trioxide (ATO) has remarkably enhanced therapeutic efficacy in treating both newly diagnosed and relapsed patients suffering from Acute Promyelocytic Leukemia (APL). Unfortunately, whether as a single agent, component of combined chemotherapy, or as a chemosensitizer or radiosensitizer combined with interventional therapy/radiotherapy, it did not benefit treatment of solid tumor (liver cancer, bladder cancer, glioma, breast cancer, cervical cancer, colorectal cancer, lung cancer, and melanoma) as seen from the clinical trials reported from the published journals or FDA-approved trials in the past decades. The clinical outcome failed to live up to our expectations, which was attributed to severe systemic toxicity and inappropriate pharmacokinetic such as low delivery efficiency and rapid renal elimination. Nanomedicine is designed to fuel up pharmaceuticals and polish off adverse effects by the moderation of their absorption, distribution, metabolism, and excretion. Nevertheless, quite a few nanodrugs (such as Doxil, Abraxane) were approved to be used clinically, and “from bench to bedside” it seems to be no easy way for most of them, such as nano-ATO. Encapsulating ATO into several types of nano-vehicles (liposome, polymer micelle, porous silicon, etc.), nano-TO can improve pharmacokinetic and become a prominent candidate to penetrate into tumor tissue, but so far no nano- ATO clinical trials have been approved around the world. On summarizing the clinical trials of ATO on solid tumor and preclinical study of nano-ATO, it is believed there is still a chance for ATO to play a critical co-helper in a comprehensive therapy to fight with solid tumor.

Background: Based on the biological significance of hederagenin-type saponins found in our previous investigation, a series of new hederagenin derivatives were designed and synthesized. Methods: Their in vitro antiproliferative activities were evaluated against the HepG2 liver cancer cell line and normal cell line L929 by MTT assay. Results: The preliminary bioassay results demonstrated that all the tested compounds 1-7 showed potent anti-hepatoma activities, and some compounds exhibited better effects than 5-fluorouracil against human hepatocellular carcinoma HepG2 cell line. Furthermore, compound 5 showed a significant antihepatoma activity against HepG2 cells with an IC50 value of 1.88 μM. Besides, all of the tested compounds showed a low cytotoxic effect against the normal cell line L929. Conclusion: All the compounds 1-7 displayed superior selectivity against human hepatocellular carcinoma HepG2 cell line, and the results suggest that the structural modifications of C ring on the hederagenin backbone are vital for modulating anti-hepatoma activities.