Species of the genus Rhododendron have been used in traditional Chinese medicine, with the medicinal herb “Manshanfong” used as an expectorant and for the treatment of acute bronchitis. Daurichromenic acid (DCA), a constituent of Rhododendron dauricum, is a meroterpenoid with antibacterial, anti-HIV, and anti-inflammatory activities. However, the mechanisms underlying these pharmacologic activities are poorly understood. To develop new drugs based on DCA, more information is required regarding its interactions with biomolecules. The present study showed that DCA inhibits the activity of the enzyme sphingomyelin synthase, with an IC₅₀ of 4 µM. The structure–activity relationships between DCA and sphingomyelin synthase were evaluated using derivatives and cyclized hongoquercin A. In addition, DCA was found to inhibit amyloid β aggregation. These results may help in the design of effective drugs based on DCA.

Antimicrobial resistance has emerged as a significant danger to global health, and the need for more effective antimicrobial resistance (AMR) control has been highlighted. Cinnamic acid is abundant in plant products and is a potential starting material for further modification, focusing on the development of new antimicrobial compounds. In the following review, we describe the classification of critical antibacterial-guided reactions applied to the main skeleton structure of cinnamic acid derivatives over the last decade. Of all of the main parts of cinnamic acids, the phenyl ring and the carboxylic group significantly affect antibacterial activity. The results presented in the following review can provide valuable insights into considerable features in the organic modification of cinnamic acids related to antibacterial medication development and the food industry.

The extracellular accumulation of aggregated amyloid-β (Aβ) in the brain leads to the early pathology of Alzheimer’s disease (AD). The administration of exogenous plant-type ceramides into AD model mice can promote the release of neuronal exosomes, a subtype of extracellular vesicles, that can mediate Aβ clearance. In vitro studies showed that the length of fatty acids in mammalian-type ceramides is crucial for promoting neuronal exosome release. Therefore, investigating the structures of plant ceramides is important for evaluating the potential in releasing exosomes to remove Aβ. In this study, we assessed plant ceramide species with D-erythro-(4E,8Z)-sphingadienine and D-erythro-(8Z)-phytosphingenine as sphingoid bases that differ from mammalian-type species. Some plant ceramides were more effective than mammalian ceramides at stimulating exosome release. In addition, using deuterium chemistry-based lipidomics, most exogenous plant ceramides were confirmed to be derived from exosomes. These results suggest that the ceramide-dependent upregulation of exosome release may promote the release of exogenous ceramides from cells, and plant ceramides with long-chain fatty acids can effectively release neuronal exosomes and prevent AD pathology.

This review focuses on diaziridine, a high strained three-membered heterocycle with two nitrogen atoms that plays an important role as one of the most important precursors of diazirine photoaffinity probes, as well as their formation and transformation. Recent research trends can be grouped into three categories, based on whether they have examined non-substituted, N-monosubstituted, or N,N-disubstituted diaziridines. The discussion expands on the conventional methods for recent applications, the current spread of studies, and the unconventional synthesis approaches arising over the last decade of publications.

Ginkgolic acid obtained as a sphingomyelin synthase inhibitor from a plant extract library inspired the concept of sphingolipid mimics. Ginkgolic acid-derived N-acyl anilines and ginkgolic acid 2-phosphate (GA2P) respectively mimic ceramide and sphingosine 1-phosphate (S1P) in structure and function. The GA2P-induced phosphorylation of ERK and internalization of S1P receptor 1 (S1P₁) indicated potent agonist activity. Docking studies revealed that GA2P adopts a similar binding conformation to the bound ligand ML5, which is a strong antagonist of S1P₁.