A rare tetrahydroimidazopyridine from the marine-derived fungus Paraconiothyrium sp. YK-03.

A new tetrahydroimidazopyridine named butyl (5R,6R,7S,8S)-5,6,7,8-tetrahydro-6,7,8-trihydroxy-5-(hydroxymethyl)imidazo[1,2-a]pyridine-2-carboxylate(1), together with eight known compounds (2-9), were isolated from the fermentation broth of a marine-derived fungus Paraconiothyrium sp. YK-03. Their chemical structures were elucidated by extensive analysis of one-dimensional and two-dimensional NMR spectroscopy, HR-ESIMS and optical rotation. Among these compounds, compound 1 represented a rare tetrahydroimidazopyridine, and compounds 2-7 were isolated from the Paraconiothyrium species for the first time. A plausible biosynthetic pathway for compound 1 was proposed.

Furfural Derivatives and Phenolic Constituents in Stemona tuberosa Lour.

Chemical investigation on the water-soluble constituents of Stemona tuberosa Lour. resulted in the isolation of a previously undescribed furfural derivative namely (S)-5-((R)-hydroxy(5-(hydroxymethyl)furan-2-yl)methyl)-5-methylfuran-2(5H)-one and twenty-five known compounds from the water decoction of the dried root tubers. Their structures were determined by analysis of the extensive spectroscopic data, including 1D/2D NMR, HR-ESI-MS, and ORD, as well as the ECD simulation and comparison. Most of them were phenolic and among them, four compounds were isolated from Stemona plants for the first time. This study uncovers diverse constituents from water decoction of S. tuberosa dedicated for its quality control and allows for the exploitation of chemical markers with potential significance for discrimination of Stemona plants.

Degradation Profiling of Nardosinone at High Temperature and in Simulated Gastric and Intestinal Fluids.

Nardosinone, a predominant bioactive product from Nardostachys jatamansi DC, is well-known for its promising therapeutic applications, such as being used as a drug on anti-inflammatory, antidepressant, cardioprotective, anti-neuroinflammatory, anti-arrhythmic, anti-periodontitis, etc. However, its stability under varying environmental conditions and its degradation products remain unclear. In this study, four main degradation products, including two previously undescribed compounds [2-deoxokanshone M (64.23%) and 2-deoxokanshone L (1.10%)] and two known compounds [desoxo-narchinol A (2.17%) and isonardosinone (3.44%)], were firstly afforded from the refluxed products of nardosinone in boiling water; their structures were identified using an analysis of the extensive NMR and X-ray diffraction data and the simulation and comparison of electronic circular dichroism spectra. Compared with nardosinone, 2-deoxokanshone M exhibited potent vasodilatory activity without any of the significant anti-neuroinflammatory activity that nardosinone contains. Secondly, UPLC-PDA and UHPLC-DAD/Q-TOF MS analyses on the degradation patterns of nardosinone revealed that nardosinone degraded more easily under high temperatures and in simulated gastric fluid compared with the simulated intestinal fluid. A plausible degradation pathway of nardosinone was finally proposed using nardosinonediol as the initial intermediate and involved multiple chemical reactions, including peroxy ring-opening, keto-enol tautomerization, oxidation, isopropyl cleavage, and pinacol rearrangement. Our findings may supply certain guidance and scientific evidence for the quality control and reasonable application of nardosinone-related products.

Phytochemistry, data mining, pharmacology, toxicology and the analytical methods of Cyperus rotundus L. (Cyperaceae): a comprehensive review.

Cyperus rotundus L. has been widely used in the treatment and prevention of numerous diseases in traditional systems of medicine around the world, such as nervous, gastrointestinal systems diseases and inflammation. In traditional Chinese medicine (TCM), its rhizomes are frequently used to treat liver disease, stomach pain, breast tenderness, dysmenorrheal and menstrual irregularities. The review is conducted to summarize comprehensively the plant's vernacular names, distribution, phytochemistry, pharmacology, toxicology and analytical methods, along with the data mining for TCM prescriptions containing C. rotundus. Herein, 552 compounds isolated or identified from C. rotundus were systematically collated and classified, concerning monoterpenoids, sesquiterpenoids, flavonoids, phenylpropanoids, phenolics and phenolic glycosides, triterpenoids and steroids, diterpenoids, quinonoids, alkaloids, saccharides and others. Their pharmacological effects on the digestive system, nervous system, gynecological diseases, and other bioactivities like antioxidant, anti-inflammatory, anti-cancer, insect repellent, anti-microbial activity, etc. were summarized accordingly. Moreover, except for the data mining on the compatibility of C. rotundus in TCM, the separation, identification and analytical methods of C. rotundus compositions were also systematically summarized, and constituents of the essential oils from different regions were re-analyzed using multivariate statistical analysis. In addition, the toxicological study progresses on C. rotundus revealed the safety property of this herb. This review is designed to serve as a scientific basis and theoretical reference for further exploration into the clinical use and scientific research of C. rotundus. Supplementary Information: The online version contains supplementary materials available at 10.1007/s11101-023-09870-3.

Sesquiterpenoids and monoterpenoids from the water decoction of Valeriana officinalis L.

Nine previously undescribed compounds including three sesquiterpenoids, three iridoids, two monoterpenoids and a furan fatty acid, along with seventeen known ones, were isolated from the water decoction of roots and rhizomes of Valeriana officinalis L. Structure elucidation of the twenty-six compounds were accomplished by analysis of the extensive spectroscopic data, and the absolute configurations of the nine previously undescribed ones were established by NOESY experiment and the electronic circular dichroism (ECD) simulations. Among them, ß-patchoulene-8-O-ß-D-glucopyranoside, 11-methoxyl-viburtinal, and protocatechuic acid showed anti-neuroinflammatory potentials by significantly inhibiting the secretion of nitric oxide (NO) on BV-2 cells upon LPS stimulation (p < 0.001) without affecting the cell viability.