Recent advances in natural phthalides: Distribution, chemistry, and biological activities

Flexible and Convergent Enantioselective Total Synthesis of (R)-Juglanaloids A and B: Two Phthalide Spiro Alkaloids with Potential Alzheimer's Disease Inhibitory Activity

Juglanaloids A and B are recently isolated natural products characterized by an unprecedented spiro bicyclic isobenzofuranone-tetrahydrobenzazepinone framework and a promising antiamyloid activity. Here reported is a straightforward convergent total synthesis of these natural products, which were obtained in high enantiomeric purity (94% and >99% ee for juglanaloids A and B, respectively) through an eight-step longest linear sequence, based on an efficient and reliable enantioselective phase-transfer-catalyzed alkylation step. Considering the interesting biological activity of juglanaloids, this convenient, highly enantioselective, flexible, and predictable synthetic strategy promises to be a powerful tool for accessing potentially bioactive spiro bicyclic phthalide-tetrahydrobenzazepinone derivatives.

Asymmetric Total Synthesis of (+)-Chuanxiongnolide L1 via a Stereoselective Oxidative Dearomatization/Diels-Alder Strategy

The first asymmetric total synthesis of chuanxiongnolide L1 was achieved in 16 steps and 1.9% overall yield by employing a bioinspired chiral auxiliary strategy. The key steps involving asymmetric oxidative dearomatization of chiral amino ether and subsequent asymmetric Diels-Alder reaction of the resulting masked chiral ortho-benzoquinone were adopted.

A comprehensive review of the botany, ethnopharmacology, phytochemistry, pharmacology, quality control and other applications of Ligustici Rhizoma et Radix

ETHNOPHARMACOLOGICAL RELEVANCE

Ligusticum sinense Oliv. and L. jeholense Nakai et Kitag. are globally recognized as medicinal botanical species, specifically the rhizomes and roots. These plant parts are collectively referred to as Ligustici Rhizoma et Radix (LReR), which is recorded in the Pharmacopoeia of the People's Republic of China (Ch. P). LReR enjoys widespread recognition in many countries such as China, Russia, Vietnam, and Korea. It is an herbal remedy traditionally employed for dispelling wind and cold, eliminating dampness, and alleviating pain. Numerous bioactive compounds have been successfully isolated and identified, displaying a diverse array of pharmacological activities and medicinal value.

THE AIM OF THE REVIEW

This review aims to primarily center on the botanical aspects, ethnopharmacology, phytochemistry, pharmacology, toxicity, quality control, and other applications of LReR to furnish a comprehensive and multidimensional foundation for future exploration and utilization.

MATERIALS AND METHODS

Relevant information about LReR was acquired from ancient books, doctoral and master's dissertations, Google Scholar, Web of Science, PubMed, China National Knowledge Infrastructure (CNKI), ScienceDirect, classical literature, and clinical reports. Several electronic databases were also incorporated.

RESULTS

In traditional usage, LReR had been traditionally employed for the treatment of anemofrigid headaches, colds, and joint pain. It possessed therapeutic properties for facial skin disorders, thereby facilitating skin regeneration. It has been subjected to comprehensive chemical analysis, resulting in the identification and isolation of 190 compounds, including phthalides, phenylpropanoids, flavonoids, phenolic acids, triterpenes, steroids, volatile oil, fatty acids, and other constituents. The pharmacological activities have been in-depth explored through modern in vivo and in vitro studies, confirming its anti-inflammatory, analgesic, and anti-melanin effects. Furthermore, it exhibited pharmacological activities such as antioxidant, anticancer, antibacterial, and vasodilatory properties. This study provides a basic to contribute to the advancement of research, medicinal applications and product development related to LReR.

CONCLUSIONS

Considering its traditional and contemporary applications, phytochemical composition, and pharmacological properties, LReR was regarded as a valuable botanical resource for pharmaceutical and pest control purposes. While certain constituents had demonstrated diverse pharmacological activities and application potential, further elucidation was required to fully understand their specific actions and underlying mechanisms. Hence, there was a need to conduct additional investigations to uncover its material foundation and mode of action.

Discovery of a Potent Antiosteoporotic Drug Molecular Scaffold Derived from Angelica sinensis and Its Bioinspired Total Synthesis

Angelica sinensis, commonly known as Dong Quai in Europe and America and as Dang-gui in China, is a medicinal plant widely utilized for the prevention and treatment of osteoporosis. In this study, we report the discovery of a new category of phthalide from Angelica sinensis, namely falcarinphthalides A and B (1 and 2), which contains two fragments, (3R,8S)-falcarindiol (3) and (Z)-ligustilide (4). Falcarinphthalides A and B (1 and 2) represent two unprecedented carbon skeletons of phthalide in natural products, and their antiosteoporotic activities were evaluated. The structures of 1 and 2, including their absolute configurations, were established using extensive analysis of NMR spectra, chemical derivatization, and ECD/VCD calculations. Based on LC-HR-ESI-MS analysis and DFT calculations, a production mechanism for 1 and 2 involving enzyme-catalyzed Diels-Alder/retro-Diels-Alder reactions was proposed. Falcarinphthalide A (1), the most promising lead compound, exhibits potent in vitro antiosteoporotic activity by inhibiting NF-κB and c-Fos signaling-mediated osteoclastogenesis. Moreover, the bioinspired gram-scale total synthesis of 1, guided by intensive DFT study, has paved the way for further biological investigation. The discovery and gram-scale total synthesis of falcarinphthalide A (1) provide a compelling lead compound and a novel molecular scaffold for treating osteoporosis and other metabolic bone diseases.

Haplotype-phased genome unveils the butylphthalide biosynthesis and homoploid hybrid origin of Ligusticum chuanxiong

Butylphthalide is one of the first-line drugs for ischemic stroke therapy, while no biosynthetic enzyme for butylphthalide has been reported. Here, we present a haplotype-resolved genome of Ligusticum chuanxiong, a long-cultivated and phthalide-rich medicinal plant in Apiaceae. On the basis of comprehensive screening, four Fe(II)- and 2-oxoglutarate-dependent dioxygenases and two CYPs were mined and further biochemically verified as phthalide C-4/C-5 desaturases (P4,5Ds) that effectively promoted the forming of (S)-3-n-butylphthalide and butylidenephthalide. The substrate promiscuity and functional redundancy featured for P4,5Ds may contribute to the high phthalide diversity in L. chuanxiong. Notably, comparative genomic evidence supported L. chuanxiong as a homoploid hybrid with Ligusticum sinense as a potential parent. The two haplotypes demonstrated exceptional structure variance and diverged around 3.42 million years ago. Our study is an icebreaker for the dissection of phthalide biosynthetic pathway and reveals the hybrid origin of L. chuanxiong, which will facilitate the metabolic engineering for (S)-3-n-butylphthalide production and breeding for L. chuanxiong.

Asymmetric Ruthenium-Catalyzed C-H Activation by a Versatile Chiral-Amide-Directing Strategy

A versatile and readily available chiral amide directing group has been developed for the ruthenium(II)-catalyzed asymmetric C-H activation. Asymmetric C-H activation of the related chiral benzamides with various olefins, aldehydes and propargylic alcohols has been accomplished with high stereoselectivities, affording a series of chiral products including 3,4-dihydroisocoumarins (up to 96 % ee), isocoumarins (up to 92 % ee), phthalides (up to 99 % ee), chiral bicyclo[2.2.1]heptanes (>20 : 1 dr), 4-alkylidene-3,4-dihydroisocoumarins (up to 97 % ee) and allenes (>20 : 1 dr). Importantly, our methodologies enabled concise syntheses of many biologically active compounds and natural products (e.g., Montroumarin, Cyclosporone E, Cyclosporone Q, Concentricolide, Chuangxinol, and Eleutherol).

A comprehensive review of the classical prescription Yiguan Jian: Phytochemistry, quality control, clinical applications, pharmacology, and safety profile

ETHNOPHARMACOLOGICAL RELEVANCE

Yiguan Jian (YGJ) is a classical prescription, which employs 6 kinds of medicinal herbs including Rehmanniae Radix, Lycii Fructus, Angelicae sinensis Radix, Glehniae Radix, Ophiopogonis Radix, and Toosendan Fructus. YGJ decoction is originally prescribed in Qing Dynasty (1636 CE ∼ 1912 CE) in China, and is commonly used to treat liver diseases. There remain abundant literature investigating YGJ decoction from multiple aspects, but few reviews summarized the research and gave a precise definition, which impedes further applications and commercialization of YGJ decoction.

AIM OF THE REVIEW

The aim of this review is to provide comprehensive descriptions of YGJ decoction, tackling with issues in the research and development of YGJ decoction.

MATERIALS AND METHODS

The literature and clinical reports were obtained from the databases including Web of Science, Science Direct, PubMed, Google Scholar, China National Knowledge Infrastructure, China Science Periodical Database, China Science and Technology Journal Database, and SinoMed since 2000. The phytochemical characteristics, quality control, pharmaceutical forms, clinical position, pharmacological effects, and toxic events of YGJ decoction were included for analysis.

RESULT

This review firstly summarized the progress of the chemical existences of YGJ decoction and discussed the advanced methods in monitoring quality of YGJ decoction and its herbal ingredients, particularly in the form of granules. Whilst this review aims to identify the pharmacological actions and clinical impacts of YGJ decoction, the medicinal materials that could provide these benefits were observed in the remaining herbs to exert the anti-fibrotic effects, anti-inflammatory activities, anti-cancer, and anti-diabetic effects, and to universally treat liver and gastric diseases. This review provided supplementary descriptions on the safety issues, especially in Glehniae Radix and Toosendan Fructus, to define the alterations between hepatoprotective activities and unclear toxics in YGJ decoction application.

CONCLUSIONS

Our comprehensively organized review discussed the chemical characteristics and the research in altering or identifying these essences. The effects of YGJ decoction on the non-clinical and clinical tests exert the good management of sophisticated diseases. In this review, current issues are discussed to inform and inspire subsequent research of YGJ decoction and other classical prescriptions.

Rapid analysis of the chemical constituents in Qiangli Dingxuan tablets using ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry

Qiangli Dingxuan (QLDX) tablet is a widely recognized traditional Chinese medicine formula that has been extensively used in China for decades to treat vertigo, tinnitus, and dizziness owing to its outstanding therapeutic outcomes. However, the complexity of the chemical components in this tablet makes it challenging to separate and identify these components. This study presented an effective and sensitive strategy for the rapid separation and simultaneous structural identification of QLDX tablet components using ultra-performance liquid chromatography with quadrupole time-of-flight tandem mass spectrometry and the UNIFI platform. Based on retention times, accurate masses, fragment ions, related literature, and authentic standards, 119 compounds were identified or tentatively characterized; these included 9 iridoids, 12 lignans, 21 phenylpropanoids, 27 flavonoids, 7 phthalides, and 43 others. Among them, 36 were confirmed using reference standards. The representative compounds with various chemical structures were studied by analyzing their fragmentation patterns and characteristic ions. In conclusion, this study established a rapid approach for characterizing the chemical constituents in QLDX tablet. The proposed approach provides a basis for qualitative analysis and quality control in the manufacturing process and is beneficial for advancing investigations into the efficacy and mechanism of action of this tablet.

Sedanolide Activates KEAP1-NRF2 Pathway and Ameliorates Hydrogen Peroxide-Induced Apoptotic Cell Death

Sedanolide is a bioactive compound with anti-inflammatory and antitumor activities. Although it has been recently suggested that sedanolide activates the nuclear factor E2-related factor 2 (NRF2) pathway, there is little research on its effects on cellular resistance to oxidative stress. The objective of the present study was to investigate the function of sedanolide in suppressing hydrogen peroxide (H2O2)-induced oxidative damage and the underlying molecular mechanisms in human hepatoblastoma cell line HepG2 cells. We found that sedanolide activated the antioxidant response element (ARE)-dependent transcription mediated by the nuclear translocation of NRF2. Pathway enrichment analysis of RNA sequencing data revealed that sedanolide upregulated the transcription of antioxidant enzymes involved in the NRF2 pathway and glutathione metabolism. Then, we further investigated whether sedanolide exerts cytoprotective effects against H2O2-induced cell death. We showed that sedanolide significantly attenuated cytosolic and mitochondrial reactive oxygen species (ROS) generation induced by exposure to H2O2. Furthermore, we demonstrated that pretreatment with sedanolide conferred a significant cytoprotective effect against H2O2-induced cell death probably due to preventing the decrease in the mitochondrial membrane potential and the increase in caspase-3/7 activity. Our study demonstrated that sedanolide enhanced cellular resistance to oxidative damage via the activation of the Kelch-like ECH-associated protein 1 (KEAP1)-NRF2 pathway.

Verbalide A~F: new phthalide derivatives from the endophytic fungus Preussia sp. CPCC 400972

There are six new phthalide derivatives Verbalide A ~ F (1-6) together with another known derivative (7) isolated from the endophytic fungus Preussia sp. CPCC 400972. Their structures were established by comprehensive spectroscopic analyses, including NMR and HRESIMS. In addition, compounds 1-7 exhibited excellent inhibitory effect against influenza A virus.

An Underutilized Food “Miwu”: Diet History, Nutritional Evaluations, and Countermeasures for Industrial Development

About 10 major crops basically feed the world. In fact, there are still a large number of plants that have not been fully explored and utilized because they have been ignored by the market and research. The expansion of food sources in various countries plays an important role in maintaining food security and nutrition security in the world. Miwu is the aerial part of the medicinal plant Rhizoma Chuanxiong belonging to a traditional local characteristic food raw material. Its edible value is still little known. Through textual research, component determination, literature survey, field research, and SWOT analysis, this paper has a comprehensive understanding of Miwu’s diet history, chemical components, safety risks, and industrial development status. It is found that Miwu has been eaten for 800 years, is rich in nutrients and active ingredients, and has no acute toxicity. In addition, the current industrial development of Miwu has significant advantages and many challenges. To sum up, Miwu is a potentially underutilized food raw material. This paper also provides countermeasures for the industrialized development of Miwu, which will provide a milestone reference for the future utilization and development of Miwu.