Eight new biflavonoids with lavandulyl units from the roots of Sophora flavescens and their inhibitory effect on PTP1B

Natural products with potential hypoglycemic activity in T2DM: 2019-2023

As currently the most common metabolic disease, type 2 diabetes mellitus (T2DM) has shown a continuous increase in the number of patients in recent decades. Most anti-T2DM drugs tend to cause some side effects. Given the pathogenesis of T2DM, natural products have emerged as an important source of anti-T2DM drugs. This article reviews natural products with potential hypoglycemic activity from 2019 to 2023. A total of 200 previously natural products were discovered on SciFinder, PubMed and Web of Science. These products were categorized based on their structural frameworks and their biological activities were summarized. Although the mechanisms of action of most compounds are unclear, these compounds could still serve as candidates for the development of lead compounds. Therefore, further structure and activity research of natural products will significantly contribute to the development of potential anti-T2DM drugs.

Highly oxidized rearranged derivatives of quinochalcone C-glycosides from Carthamus tinctorius

Safflopentsides A-C (1-3), three highly oxidized rearranged derivatives of quinochalcone C-glycosides, were isolated from the safflower yellow pigments. Their structures were determined based on a detailed spectroscopic analysis (UV, IR, HR-ESI-MS, 1D and 2D NMR), and the absolute configurations were confirmed by the comparison of experimental ECD spectra with calculated ECD spectra. Compounds 1-3 have an unprecedented cyclopentenone or cyclobutenolide ring A containing C-glucosyl group, respectively. The plausible biosynthetic pathways of compounds have been presented. At 10 μM, 2 showed strong inhibitory activity against rat cerebral cortical neurons damage induced by glutamate and oxygen sugar deprivation.

Six undescribed lavandulylated flavonoids with PTP1B inhibition from the roots of Sophora flavescens

Six undescribed lavandulylated flavonoids (1-6) were isolated from the roots of Sophora flavescens. Remarkably, compounds 1 and 2, which were composed of a flavane unit and a phloroglucinol unit, were the first reported dimers. Compounds 3 and 4 were the first reported neoflavonoids with lavandulyl units. Compounds 5 and 6 were chalcone with oxidized lavandulyl units. Their structures were fully characterized by cumulative analyses of UV, IR, HRESIMS, NMR and ECD spectroscopic data, along with computational calculations through density functional theory. Compounds 1 and 2 showed significant protein tyrosine phosphatase-1B inhibitory activities with IC50 values of 2.669 and 3.596 μM, respectively.

Clinical development and informatics analysis of natural and semi-synthetic flavonoid drugs: A critical review

BACKGROUND

Flavonoids are one of the most important metabolites with vast structural diversity and a plethora of potential pharmacological applications, which have drawn considerable attention in the laboratory. Nevertheless, it remains uncertain how many candidates were progressed to clinical application.

AIM OF REVIEW

We carried out a critical review of natural and semi-synthetic flavonoid drugs and candidates undergoing different clinical phases worldwide by applying an adequate search method and conducted a brief cheminformatic and bioinformatic analysis. It was expected that the obtained results might narrow the screening scope and reduce the cost of drug research and development.

KEY SCIENTIFIC CONCEPTS OF REVIEW

To our knowledge, this is the most systematic summarization of flavonoid-based drugs and clinical candidates to date. It was found that a total of 19 flavonoid-based drugs have been approved for the market, and of these, natural flavonoids accounted for 52.6%. Besides, a total of 36 flavonoid-based clinical candidates are undergoing or suspended in different phases, and of these, natural flavonoids account for 44.4%. Thus, natural flavonoids remain the best option for finding novel agents/active templates, and when investigated in conjunction with synthetic chemicals and biologicals, they offer the potential to discover novel structures that can lead to effective agents against a variety of human diseases. Additionally, flavonoid-based marketed drugs have been successful in cardiovascular treatment, and the related drugs account for more than 30% of marketed drugs. However, the use of flavonoids as antineoplastic and immunomodulating agents is not likely for approximately 50% of the candidates suspended in the clinical stage. Interestingly, the marketed drugs covered a broader range of chemical spaces based on size, polarity, and three-dimensional structure compared to the clinical candidates. In addition, flavonoid glycosides with poor oral bioavailability account for 36.8% of the marketed drugs, and thus, they could be thoroughly investigated.

Phytochemistry and pharmacology of natural prenylated flavonoids

Prenylated flavonoids are a special kind of flavonoid derivative possessing one or more prenyl groups in the parent nucleus of the flavonoid. The presence of the prenyl side chain enriched the structural diversity of flavonoids and increased their bioactivity and bioavailability. Prenylated flavonoids show a wide range of biological activities, such as anti-cancer, anti-inflammatory, neuroprotective, anti-diabetic, anti-obesity, cardioprotective effects, and anti-osteoclastogenic activities. In recent years, many compounds with significant activity have been discovered with the continuous excavation of the medicinal value of prenylated flavonoids, and have attracted the extensive attention of pharmacologists. This review summarizes recent progress on research into natural active prenylated flavonoids to promote new discoveries of their medicinal value.

In Vitro and In Silico Potential Inhibitory Effects of New Biflavonoids from Ochna rhizomatosa on HIV-1 Integrase and Plasmodium falciparum

The aim of this study was to identify bioactive secondary metabolites from Ochna rhizomatosa with potential inhibitory effects against HIV and Plasmodium falciparum. A phytochemical study of O. rhizomatosa root barks resulted in the identification of three new biflavonoids (1–3), along with four known ones (4–7). Compound 7 (Gerontoisoflavone A) was a single flavonoid present in the rootbark of the plant and was used as a reference. Compound 1 (IC₅₀ = 0.047 µM) was the only one with a noteworthy inhibitory effect against HIV-1 integrase in vitro. Chicoric acid (IC₅₀ = 0.006 µM), a pure competitive inhibitor of HIV-1 integrase, was used as control. Compound 2 exhibited the highest antiplasmodial activity (IC₅₀ = 4.60 µM) against the chloroquine-sensitive strain of Plasmodium falciparum NF54. Computational molecular docking revealed that compounds 1 and 2 had the highest binding score (−121.8 and −131.88 Kcal/mol, respectively) in comparison to chicoric acid and Dolutegravir (−116 and −100 Kcal/mol, respectively), towards integrase receptor (PDB:3LPT). As far as Plasmodium-6 cysteine s48/45 domain inhibition is concerned, compounds 1 and 2 showed the highest binding scores in comparison to chloroquine, urging the analysis of these compounds in vivo for disease treatment. These results confirm the potential inhibitory effect of compounds 1 and 2 for HIV and malaria treatment. Therefore, our future investigation to find inhibitors of these receptors in vivo could be an effective strategy for developing new drugs.

Chemical diversity, biological activities and Traditional uses of and important Chinese herb Sophora

BACKGROUND

Sophora flavescens Aiton (SF), also known as Kushen (Chinese:), has been an important species in Chinese medicine since the Qin and Han dynasties. It is also recognized as a plant resource suitable for the globalization of Chinese medicine. Traditionally, it has been used in various ethnic medical systems in East Asia, especially in China, to kill insects and dispel dampness. Sophora flavescens is commonly used for clearing heat-clearing, killing worms, and diuretic. Nowdays, accumulating studies demonstrated its anticancer and cardioprotection.

OBJECTIVE OF THE REVIEW

This paper aims to systematically review information on the genus, pharmacological and toxicological significance, chemical composition and biological activity of Sophora flavescens. To promoting its development and application. To summarize recent findings regarding to the metabolism, pharmacological/toxicological effects of Sophora flavescens.

MATERIAL AND METHODS

Online academic databases (including PubMed, Google Scholar, Web of Science and CNKI) were searched using search terms of "Sophora flavescens Aiton", "Ku shen", "Pharmacology", "Active ingredient", "Toxicology" and combinations to include published studies of Sophora flavescens Aiton primarily from 1970-2021. Several critical previous studies beyond this period were also included and other related terms.

CONCLUSION

Sophora flavescens has a broad spectrum of biological activities associated with Sophora flavescens has been considered a valuable resource in both traditional and modern medicine. However, there is a lack of in-depth studies on the medicinal uses of Sophora flavescens. Moreover, further studies on single chemical components should be conducted based on the diversity of chemical structures, significant biological activities and clinical applications. The discovery of its bioactive molecules and multi-component interactions would be of great importance for the clinical application of Sophora flavescens spp. Detailed pharmacological and toxicological studies on the classic prescriptions of Sophora flavescens are also needed. It is more beneficial to the wide application of SF plant and facilitates the worldwide promotion of modern Chinese medicine. However, an increasing number of reports indicate that the administration of Sophora flavescens has serious adverse effects. Its main toxic effects are neurotoxicity and acute toxicity, which have caused widespread concern worldwide. In addition, the alkaloids of Sophora flavescens are distributed in the heart, liver, stomach and large intestine. They are excreted from the body through gluconeogenesis, which is the mode of action of certain therapeutic mechanisms of action such as anticancer. The detailed metabolic study of alkaloids and other components of Sophora flavescens in vivo needs to be further investigated. It is important to improve the pharmacological effects and reduce the toxicity of Sophora flavescens. For this purpose, structural modification of active components of Sophora flavescens or combination with other drugs is very essential.

Approaches to Decrease Hyperglycemia by Targeting Impaired Hepatic Glucose Homeostasis Using Medicinal Plants

Liver plays a pivotal role in maintaining blood glucose levels through complex processes which involve the disposal, storage, and endogenous production of this carbohydrate. Insulin is the hormone responsible for regulating hepatic glucose production and glucose storage as glycogen, thus abnormalities in its function lead to hyperglycemia in obese or diabetic patients because of higher production rates and lower capacity to store glucose. In this context, two different but complementary therapeutic approaches can be highlighted to avoid the hyperglycemia generated by the hepatic insulin resistance: 1) enhancing insulin function by inhibiting the protein tyrosine phosphatase 1B, one of the main enzymes that disrupt the insulin signal, and 2) direct regulation of key enzymes involved in hepatic glucose production and glycogen synthesis/breakdown. It is recognized that medicinal plants are a valuable source of molecules with special properties and a wide range of scaffolds that can improve hepatic glucose metabolism. Some molecules, especially phenolic compounds and terpenoids, exhibit a powerful inhibitory capacity on protein tyrosine phosphatase 1B and decrease the expression or activity of the key enzymes involved in the gluconeogenic pathway, such as phosphoenolpyruvate carboxykinase or glucose 6-phosphatase. This review shed light on the progress made in the past 7 years in medicinal plants capable of improving hepatic glucose homeostasis through the two proposed approaches. We suggest that Coreopsis tinctoria, Lithocarpus polystachyus, and Panax ginseng can be good candidates for developing herbal medicines or phytomedicines that target inhibition of hepatic glucose output as they can modulate the activity of PTP-1B, the expression of gluconeogenic enzymes, and the glycogen content.

Structurally diverse biflavonoids from the fruits of Citrus medica L. var. sarcodactylis Swingle and their hypolipidemic and immunosuppressive activities

The fruit of Citrus medica L. var. sarcodactylis Swingle is not only used as a traditional medicinal plant, but also served as a delicious food. Six new (3'→7″)-biflavonoids (1-6), and twelve known biflavonoid derivatives (7-18) were isolated and characterized from the fruits of C. medica L. var. sarcodactylis Swingle for the first time. Their structures were determined by extensive and comprehensive analyzing NMR, HR-ESI-MS, UV, and IR spectral data coupled with the data described in the literature. Compounds (1-18) were evaluated for their hypolipidemic activities with Orlistat as the positive control, and assayed for their immunosuppressive activities with Dexamethasone as the positive control, respectively. Among them, compounds (1-3) exhibited moderate inhibition of pancreatic lipase activity by inhibiting 68.56 ± 1.40%, 56.18 ± 1.57%, 53.51 ± 1.59% of pancreatic lipase activities at the concentration of 100 μM, respectively. Compounds (4-6) and 8 showed potent immunosuppressive activities with the IC₅₀ values from 16.83 ± 1.32 to 50.90 ± 1.79 μM. The plausible biogenetic pathway and preliminary structure activity relationship of the selected compounds were scientifically summarized and discussed in this study.

Bioactivity-guided isolation of compounds from Sophora flavescens with antibacterial activity against Acinetobacter baumannii

Bioactivity-guided fraction of an extract of Sophora flavescens to identify antibacterial compounds against Acinetobacter baumannii, led to the isolation of two new compounds, (2″R)-5-methoxy-7-hydroxy-8-lavandulylchromone (13) and (2S,βS)-(-)-sophobiflavonoid CE (19), and 18 known flavonoids, (6aR,11aR)-(-)-maackiain (1), (2S)-(-)-8-prenylnaringenin (2), (2S)-(-)-exiguaflavanone K (3), (2S)-(-)-sophoraflavanone G (4), (2S)-(-)-leachianone A (5), (2S)-(-)-kushenol E (6), (2S)-(-)-leachianone G (7), (±)-kushenol F (8), (2S)-(-)-kurarinone (9), (2S)-(-)-kurarinol (10), (2 R,3R)- (+)-3,7,4'-trihydroxy-5-methoxy-8-prenylflavanone (11), (2S)-(-)-isoxanthohumol (12), (2S)-(-)-2'-methoxykurarinone (14), (2 R,3R)-(+)-kushenol I (15), calycosin (16), kuraridin (17), (2S)-(-)-kushenol A (18), and trifolirhizin (20). Their structures were elucidated based on NMR, MS, and CD spectroscopic analysis. Among them, 1, 2, 5, and 15 exerted modest antibacterial activity against A. baumannii, with MIC₉₅ of 128-256 μg/mL for 2 and 256-512 μg/mL for 1, 5 and 15.

Panduratins Q-Y, dimeric metabolites from Boesenbergia rotunda and their antiausterity activities against the PANC-1 human pancreatic cancer cell line

A methanolic extract of the rhizomes of Boesenbergia rotunda showed potent preferential cytotoxicity against PANC-1 human pancreatic cancer cells under nutrient deficiency conditions with a PC₅₀ value of 6.6 μg/mL. Bioactivity-guided phytochemical investigation of the rhizomes of B. rotunda led to the isolation of nine undescribed dimeric metabolites, panduratins Q-Y. Their structures were elucidated based on NMR, MS, and ECD spectroscopic data interpretation. Panduratins Q-S and U-W exhibited potent cytotoxicity towards PANC-1 cell line with the PC₅₀ values ranging from 0.8 to 6.3 μM. Panduratin W, which possessed a cyclohexenylchalcone-linked flavanone skeleton, showed the most cytotoxicity with a PC₅₀ value of 0.8 μM under nutrient-deprived medium.

Biflavonoid as potential 3-chymotrypsin-like protease (3CLpro) inhibitor of SARS-Coronavirus

3CL protease is one of the key proteins expressed by SARS-Coronavirus-2 cell, the potential to be targeted in the discovery of antivirus during this COVID-19 pandemic. This protein regulates the proteolysis of viral polypeptide essential in forming RNA virus. 3CL protease (3CLpro) was commonly targeted in the previous SARS-Coronavirus including bat and MERS, hence, by blocking this protein activity, the coronavirus should be eradicated. This study aims to review the potency of biflavonoid as the SARS-Coronavirus-2 3CLpro inhibitor. The review was initiated by describing the chemical structure of biflavonoid and followed by listing its natural source. Instead, the synthetic pathway of biflavonoid was also elaborated. The 3CLpro structure and its function were also illustrated followed by the list of its 3D-crystal structure available in a protein data bank. Lastly, the pharmacophores of biflavonoid have been identified as a protease inhibitor, was also discussed. This review hopefully will help researchers to obtain packed information about biflavonoid which could lead to the study in designing and discovering a novel SARS-Coronavirus-2 drug by targetting the 3CLpro enzyme.

Archromones A-F, unusual polycyclic dearomatic geranylquinol derivatives from the roots of Arnebia euchroma

Eight new geranylquinol derivatives (1-8) were purified from the roots of Arnebia euchroma. Compounds 1-6 possess an unprecedented dearomatic benzocogeijerene skeleton with a rare trans-fused hydronaphthalene moiety. Their structures and absolute configurations were elucidated by HRESIMS, NMR, ECD, and X-ray diffraction. A convenient strategy for rapid determination of the relative configuration of H-1/H-7/Me-16 and the absolute configuration at C-1 for 1-6 was summarized. Compound 2 exhibited cytotoxicity against all the tested cell lines, namely PC9, BGC823, HCT116, HepG2, HeLa, and U87-MG, with IC50 values ranging from 13.7 to 29.3 μM.

Dihydrochalcones: Methods of Acquisition and Pharmacological Properties-A First Systematic Review

Dihydrochalcones are a class of secondary metabolites, for which demand in biological and pharmacological applications is still growing. They posses several health-endorsing properties and, therefore, are promising candidates for further research and development. However, low content of dihydrochalcones in plants along with their low solubility and bioavailability restrict the development of these compounds as clinical therapeutics. Therefore, chemomicrobial and enzymatic modifications are required to expand their application. This review aims at analyzing and summarizing the methods of obtaining dihydrochalcones and of presenting their pharmacological actions that have been described in the literature to support potential future development of this group of compounds as novel therapeutic drugs. We have also performed an evaluation of the available literature on beneficial effects of dihydrochalcones with potent antioxidant activity and multifactorial pharmacological effects, including antidiabetic, antitumor, lipometabolism regulating, antioxidant, anti-inflammatory, antibacterial, antiviral, and immunomodulatory ones. In addition, we provide useful information on their properties, sources, and usefulness in medicinal chemistry.

Osteoarthritis Is a Low-Grade Inflammatory Disease: Obesity's Involvement and Herbal Treatment

Osteoarthritis (OA) is considered a major cause of disability around the globe. This handicapping disease causes important cartilage and bone alteration that is associated with serious pains and loss of joint function. Despite its frequent association with obesity, the aetiology of OA is not fully understood. In this review, the different aspects of OA and its correlation with obesity were analysed. Through examining different mechanisms by which obesity may trigger and/or exacerbate OA, we point out some relevant signalling pathways that may evolve as candidates for pharmacological drug development. As such, we also suggest a review of different herbal medicines (HMs) and their main compounds, which specifically interfere with the identified pathways. We have shown that obesity's involvement in OA is not only limited to the mechanical weight exerted on the joints (mechanical hypothesis), but also induces an inflammatory state by different mechanisms, including increased leptin expression, compromised gut mucosa, and/or gut microbiota disruption. The main signalling pathways involved in OA inflammation, which are associated with obesity, are protein tyrosine phosphatase 1B (PTP1B) and TLR4 or DAP12. Moreover, we also underline the contamination of plant extracts with LPS as an important factor to consider when studying HM's effects on articular cells. By summarizing recent publications, this review aims at highlighting newly established aspects of obesity involvement in OA other than the mechanical one.

The pharmacology of the genus Sophora (Fabaceae): An updated review

BACKGROUND

The genus Sophora (Fabaceae) represents one of the important medicinal plant genera regarding its chemical constituents and outstanding pharmacological activities.

PURPOSE

In this review, we surveyed the latest findings on the bioactivities of different Sophora extracts and isolated phytochemicals during the past 8 years (2011-2019) updating the latest review article in 2011. The aim of this review is to focus on the molecular pharmacology of Sophora species to provide the rationale basis for the development of novel drugs.

RESULTS

Sophora and its bioactive compounds possess outstanding pharmacological properties, especially as anticancer and anti-inflammatory drugs, in addition to its antioxidant, antibacterial, antifungal and antiviral properties.

CONCLUSION

Based on their use in traditional medicine, Sophora species exert a plethora of cellular and molecular activities, which render them as attractive candidates for rationale drug development. Randomized, placebo-controlled clinical trials are required for further integration of Sophora-based phototherapies into conventional medicine.

Total synthesis of wikstrol A and wikstrol B

The first total synthesis of wikstrol A and wikstrol B was achieved by employing aldol reaction, Sharpless asymmetric dihydroxylation, regioselective iodination, Sonogashira coupling, and rhodium-catalyzed oxidative coupling as key steps. The structure of the key intermediate for wikstrol A was confirmed via its derivative by single-crystal X-ray analysis.