Mini Reviews in Medicinal Chemistry - Volume 20, Issue 19, 2020

Cancer is the world's second-largest cause of mortality and one of the biggest global health concerns. The prevalence and mortality rates of cancer remain high despite significant progress in cancer therapy. The search for more effective, as well as less toxic treatment methods for cancer, is at the focus of current studies. Thiophene and its derivatives have surged as an influential scaffold, which, because of their appreciable diversity in biological activities, has drawn the concerned interest of the researchers in the field of medicinal chemistry. By the affluent introduction of its derivatives, which have antioxidant, anti-inflammatory, antimicrobial, and anticancer activities, the adaptability of the thiophene moiety has been displayed. The nature and positioning of the substitutions significantly impacted thiophene moiety activity. This decent array in the living response account about this moiety has picked plentiful researcher’s consideration to inquire about it to its peculiar potential across certain activities. In the field of cancer therapy against different cancer cells, the structure-activity relationship for each of the derivatives showed an excellent understanding of thiophene moiety. Information from the various articles revealed the key role of thiophene moiety and its derivatives to develop the vital lead compound. The essential anticancer mechanisms identified include inhibition of the topoisomerase, inhibition of tyrosine kinase, tubulin interaction and apoptosis induction through the activation of reactive oxygen species. This review is an endeavor to promote the anticancer potential of the derivatives, whether having thiophene or condensed thiophene as a core moiety or as a substituent that can lead in the future to synthesize varieties of chemotherapeutic entities in the field of cancer treatment.

Marine sponge-associated fungi are promising sources of structurally interesting and bioactive secondary metabolites. Great plenty of natural products have been discovered from spongeassociated fungi in recent years. Here reviewed are 571 new compounds isolated from marine fungi associated with sponges in 2010-2018. These molecules comprised eight different structural classes, including alkaloids, polyketides, terpenoids, meroterpenoids, etc. Moreover, most of these compounds demonstrated profoundly biological activities, such as antimicrobial, antiviral, cytotoxic, etc. This review systematically summarized the structural diversity, biological function, and future potential of these novel bioactive natural products for drug discovery.

Liver disease is global health problem. Paracetamol (APAP) is used as an analgesic drug and is considered safe at therapeutic doses, but at higher doses, it causes acute liver injury. N-acetyl-p- Benzoquinone Imine (NAPQI) is a reactive toxic metabolite produced by biotransformation of APAP. NAPQI damages the liver by oxidative stress and the formation of protein adducts. The glutathione precursor N-acetylcysteine (NAC) is the only approved antidote against APAP hepatotoxicity, but it has limited hepatoprotective effects. The search for new drugs and novel therapeutic intervention strategies increasingly includes testing plant extracts and other natural products. Plumeria pudica (Jacq., 1760) is a plant that produces latex containing molecules with therapeutic potential. Proteins obtained from this latex (LPPp), a well-defined mixture of chitinases, proteinases proteinase inhibitors have shown anti-inflammatory, antinociceptive, antidiarrheal effects as well as a protective effect against ulcerative colitis. These studies have demonstrated that LPPp acts on parameters such as Glutathione (GSH) and Malondialdehyde (MDA) concentration, Superoxide Dismutase (SOD) activity, Myeloperoxidase (MPO) activity, and TNF- α IL1-β levels. Since oxidative stress and inflammation have been reported to affect the initiation and progression of liver injury caused by APAP, it is suggested that LPPp can act on aspects related to paracetamol hepatoxicity. This article brings new insights into the potential of the laticifer proteins extracted from the latex of P. pudica and opens new perspectives for the treatment of this type of liver disease with LPPp.

Naturally occurring naphthoquinones (NQs) comprising highly reactive small molecules are the subject of increasing attention due to their promising biological activities such as antioxidant, antimicrobial, apoptosis-inducing activities, and especially anticancer activity. Lapachol, lapachone, and napabucasin belong to the NQs and are in phase II clinical trials for the treatment of many cancers. This review aims to provide a comprehensive and updated overview on the biological activities of several new NQs isolated from different species of plants reported from January 2013 to January 2020, their potential therapeutic applications and their clinical significance.

Saurauia roxburghii Wall. is an interesting plant, found growing chiefly along the eastern and south-eastern countries of Asia. The various ethnic groups of these regions use the plant as a medication for relieving a wide spectrum of diseases and conditions, including indigestion, boils, fever, gout, piles, eczema, asthma, ulcers, bronchitis, epilepsy, and hepatitis B. This review aims to appraise the vernacular information, botanical characterization, geographical distribution, traditional uses, phytochemistry, and pharmacological activities of S. roxburghii as well as to conduct a critical analysis on the findings. To understand the therapeutic potential and provide an overall idea about the ethnomedicinal practices, phytochemistry, and pharmacological activities of S. roxburghii, relevant information was collected via a library and electronic search of online journals, books, and reputed databases. Phytochemical examination revealed the presence of alkaloids, glycosides, O-glycosides, flavonoids, carbohydrates, saponins, steroids, reducing sugars, tannins, phlobatannins, and triterpenoids. The sterols were identified as Stigmasterol and beta-Sitosterol. The triterpenes were found to be Ursolic acid, Corosolic acid, Maslinic acid, 24-Hydroxy corosolic acid, 3b,7b,24-trihydroxy-urs-12-en-28-oic acid, Oleanolic acid, beta-Amyrin, cis-3-O-p-Hydroxycinnamoyl ursolic acid, trans-3-O-p- Hydroxycinnamoyl ursolic acid, and 7,24-dihydroxyursolic acid. Several in-vivo and in-vitro tests revealed anti-bacterial, anti-cancer, anti-diabetic, anti-oxidant, and anti-viral activities of the plant leaves. Detailed analysis of the information collected on S. roxburghii suggested some promising leads for future drug development. However, many scientific gaps were found in the study of this and further extensive investigation is needed to fully understand the mechanism of action of the active constituents and exploit its therapeutic promises.

Sulfonamides have been in clinical use for many years, and the development of bioactive substances containing the sulfonamide subunit has grown steadily in view of their important biological properties such as antibacterial, antifungal, antiparasitic, antioxidant, and antitumour properties. This review addresses the medicinal chemistry aspects of sulfonamides; covering their discovery, the structure- activity relationship and the mechanism of action of the antibacterial sulfonamide class, as well as the physico-chemical and pharmacological properties associated with this class. It also provides an overview of the various biological activities inherent to sulfonamides, reporting research that emphasises the importance of this group in the planning and development of bioactive substances, with a special focus on potential antitumour properties. The synthesis of sulfonamides is considered to be simple and provides a diversity of derivatives from a wide variety of amines and sulfonyl chlorides. The sulfonamide group is a non-classical bioisostere of carboxyl groups, phenolic hydroxyl groups and amide groups. This review highlights that most of the bioactive substances have the sulfonamide group, or a related group such as sulfonylurea, in an orientation towards other functional groups. This structural characteristic was observed in molecules with distinct antibacterial activities, demonstrating a clear structure-activity relationship of sulfonamides. This short review sought to contextualise the discovery of classic antibacterial sulfonamides and their physico-chemical and pharmacological properties. The importance of the sulfonamide subunit in Medicinal Chemistry has been highlighted and emphasised, in order to promote its inclusion in the planning and synthesis of future drugs.

Cardiovascular disease (CVD) is the leading cause of mortality, morbidity, and financial losses and has a high prevalence across the world. Several studies have investigated the association between various CVD types with zinc and copper status as the essential minerals for the human body, proposing contradictory and similar results. This narrative review aimed to survey the correlations between zinc and copper status in the human body and some risk factors of CVD, as well as the assessment methods of zinc and copper status in the human body. According to the reviewed articles, zinc and copper deficiency may increase the risk of coronary heart disease, valvular regurgitation, and myocardial lesions, cardiac hypertrophy. Furthermore, it could lead to the expanded mitochondrial compartments of the heart, acute and chronic heart failure, and elevation of inflammation markers, such as interleukin-1 (IL-1) and IL-6. Two methods are primarily used for the assessment of zinc and copper in the human body, including the direct method (measurement of their concentrations) and indirect method (determining the activity of zinc- and copper-containing enzymes). Both these methods are considered reliable for the assessment of the zinc and copper levels in healthy individuals. Serum or plasma levels of these elements are also commonly used for the assessment of the correlation between zinc and copper status and CVD. But, which one is a more accurate indicator in relation to CVD is not yet clear; therefore, further studies are required in this field.