Oleanolic acid (OA), a pentacyclic triterpenoid, exhibits a broad spectrum of biological activities, including antitumor, antiviral, antibacterial, anti-inflammatory, hepatoprotective, hypoglycemic, and hypolipidemic effects. Since its initial isolation and identification, numerous studies have reported on the structural modifications and pharmacological activities of OA and its derivatives. Despite this, there has been a dearth of comprehensive reviews in the past two decades, leading to challenges in subsequent research on OA. Based on the main biological activities of OA, this paper comprehensively summarized the modification strategies and structure-activity relationships (SARs) of OA and its derivatives to provide valuable reference for future investigations into OA.
Oleanolic Acid ; Structure-Activity Relationship ; Anti-Inflammatory Agents/pharmacology* ; Triterpenes ; Anti-Bacterial Agents/pharmacology*

OBJECTIVE: This study aimed to compare 9 perfluoroalkyl sulfonic acids (PFSA) with carbon chain lengths (C4-C12) to inhibit human placental 3β-hydroxysteroid dehydrogenase 1 (3β-HSD1), aromatase, and rat 3β-HSD4 activities. METHODS: Human and rat placental 3β-HSDs activities were determined by converting pregnenolone to progesterone and progesterone secretion in JEG-3 cells was determined using HPLC/MS-MS, and human aromatase activity was determined by radioimmunoassay. RESULTS: PFSA inhibited human 3β-HSD1 structure-dependently in the order: perfluorooctanesulfonic acid (PFOS, half-maximum inhibitory concentration, IC ₅₀: 9.03 ± 4.83 μmol/L) > perfluorodecanesulfonic acid (PFDS, 42.52 ± 8.99 μmol/L) > perfluoroheptanesulfonic acid (PFHpS, 112.6 ± 29.39 μmol/L) > perfluorobutanesulfonic acid (PFBS) = perfluoropentanesulfonic acid (PFPS) = perfluorohexanesulfonic acid (PFHxS) = perfluorododecanesulfonic acid (PFDoS) (ineffective at 100 μmol/L). 6:2FTS (1H, 1H, 2H, 2H-perfluorooctanesulfonic acid) and 8:2FTS (1H, 1H, 2H, 2H-perfluorodecanesulfonic acid) did not inhibit human 3β-HSD1. PFOS and PFHpS are mixed inhibitors, whereas PFDS is a competitive inhibitor. Moreover, 1-10 μmol/L PFOS and PFDS significantly reduced progesterone biosynthesis in JEG-3 cells. Docking analysis revealed that PFSA binds to the steroid-binding site of human 3β-HSD1 in a carbon chain length-dependent manner. All 100 μmol/L PFSA solutions did not affect rat 3β-HSD4 and human placental aromatase activity. CONCLUSION Carbon chain length determines inhibitory potency of PFSA on human placental 3β-HSD1 in a V-shaped transition at PFOS (C8), with inhibitory potency of PFOS > PFDS > PFHpS > PFBS = PFPS = PFHxS = PFDoS = 6:2FTS = 8:2FTS.
Humans ; Pregnancy ; Female ; Rats ; Animals ; Placenta ; Progesterone/pharmacology* ; Aromatase/pharmacology* ; Cell Line, Tumor ; Fluorocarbons ; Alkanesulfonic Acids ; Structure-Activity Relationship ; Hydroxysteroid Dehydrogenases/pharmacology*

Aconiti Lateralis Radix Praeparata polysaccharides(AP) are a class of bioactive macromolecules extracted from the herbs of Aconiti Lateralis Radix Praeparata and its various processed products. Since the AP was first separated in 1986, its pharmacological effects include immune regulation, anti-tumor, anti-depression, organ protection, hypoglycemia, and anti-inflammatory had been found. In recent years, with the development of polysaccharide extraction, separation, and structure identification technologies, more than 20 kinds of AP have been separated from Aconiti Lateralis Radix Praeparata and its processed products, and they have ob-vious differences in relative molecular weight, monosaccharide composition, glycosidic bond, structural characteristics, and biological activities. In particular, AP may be dissolved, degraded, or allosteric under the complex processing environment of fermentation, soaking, cooking, etc., leading to the diversified structure of AP, which provides a possibility for further understanding of the structure-activity relationship of AP. Therefore, this study systematically reviewed the research progress on the structure and structure-activity relationship of AP, summarized the biological activity and potential action mechanism of AP, and discussed the technical challenges in the development and application of AP, so as to promote the quality control and further development and utilization of AP.
Drugs, Chinese Herbal/chemistry* ; Aconitum/chemistry* ; Polysaccharides/pharmacology* ; Structure-Activity Relationship ; Technology

As a traditional Chinese herb and functional food, the fruits of Lycium barbarum has been widely used for thousands of years in China. L. barbarum polysaccharides(LBPs) are predominant active components, which have immunomodulatory, antioxidant, hypoglycemic, neuroprotective, anti-tumor, and prebiotic activities. The molecular weight, monosaccharide composition, glycosidic bond, branching degree, protein content, chemical modification, and spatial structure of LBPs are closely related to their biological activity. Based on the previous studies of this research team, this paper systematically combed and integrated the research progress of structure, function, and structure-activity relationship of LBPs. At the same time, some problems restricting the clarification of the structure-activity relationship of LBPs were considered and prospected, hoping to provide references for the high value utilization of LBPs and in-depth exploration of their health value.
Lycium/chemistry* ; Drugs, Chinese Herbal/chemistry* ; Structure-Activity Relationship ; Antioxidants/pharmacology* ; Antineoplastic Agents ; Polysaccharides/chemistry*

Polysaccharides have significant immunomodulatory activity and have good development value in food and medicine fields. At present, there are many studies on the chemical structure and immune activity of polysaccharides, but the relationship between them of polysaccharides has not been fully explained, which limits the further development and utilization of polysaccharide resources. The immune activity of polysaccharides is closely related to their own structure. This paper systematically summarized the relationship between the relative molecular weight, monosaccharide composition, glycosidic bond types, chemical modification, and advanced conformation of polysaccharides and the immune regulation, aiming to provide references for the profound study of polysaccharide structure-activity relationship and utilization of polysaccharides.
Monosaccharides/chemistry* ; Structure-Activity Relationship ; Molecular Weight ; Antioxidants/pharmacology* ; Polysaccharides/chemistry*

The chemical characterization analysis of a medical device often results in chemical substances with unknown toxicities. While identification of each individual toxicity could result in a time-consuming hurdle with tremendous labor and financial burden, quantitative structure-activity relationship (QSAR) is of great significance for toxicity risk assessment of such chemical substances. By establishing quantitative relationship between the molecular structures or active groups of similar chemical compounds with their biological activities, QSAR can be utilized to predict the toxicity of such target compounds with significantly reduced cost and time. In this article, the authors generally summarized the mechanisms of QSAR approaches, current applications of QSAR modeling in the field of medical device, an introduction of the characteristics of publicly and commercially-available QSAR software, and briefly explored future trends of QSAR modeling in medical device toxicological risk assessment. The utilization of QSAR would undoubtedly further advance the toxicological risk assessment of medical devices.
Quantitative Structure-Activity Relationship ; Risk Assessment ; Software

Diversity-oriented synthesis is aimed to increase the chemical diversity of target natural products for extensive biological activity evaluation. Indole ring is an important functional group in a large number of drugs and other biologically active agents, and indole-containing natural products have been frequently isolated from marine sources in recent years. In this paper, a series of indole-containing marine natural hyrtioreticulin derivatives, including 19 new ones, were designed, synthesized through a key Pictet-Spengler reaction, and evaluated for their inflammation related activity. Compound 13b displayed the most promising activity by inhibiting TNF-α cytokine release with an inhibitory rate of 92% at a concentration of 20 μmol·L^-1. A preliminary structure-activity relationship analysis was also discussed. This research may throw light on the discovery of marine indole alkaloid derived anti-inflammatory drug leads.
Animals ; Anti-Inflammatory Agents/pharmacology* ; Biological Products/pharmacology* ; Indole Alkaloids/pharmacology* ; Porifera ; Structure-Activity Relationship

The spread of antibiotic-resistant bacteria and exhausted drug leads render some infections untreatable now and in the future. To deal with these "new challenges", scientists tend to re-pick up "old antibiotics". Fusidane-type antibiotics have been known for nearly 80 years as potent antibacterial agents against gram-positive bacteria, especially Staphylococci, and represent the only triterpene-derived antibiotic class in clinical setting. These attractive characteristics have drawn renewed attention on fusidane-type antibiotics in recent decades. Isolation, characterization, biological evaluation, as well as chemical modifications of fusidane-type antibiotics are increasingly being reported. Combinatorial biosynthesis of this type of antibiotics has been successfully utilized not only for elucidating the biosynthetic pathways, but also for expanding their structural diversity. Some isolated and synthetic compounds exhibit comparable or even more potent biological activity than fusidic acid. This review provides an overview of progress on the studies of structure and biology of fusidane-type antibiotics from 1943 to April 2021. The informative structure-activity relationship is also highlighted.
Anti-Bacterial Agents/pharmacology* ; Bacteria ; Biology ; Structure-Activity Relationship

Bacterial surface glycans perform a diverse and important set of biological roles, and have been widely used in the treatment of bacterial infectious diseases. The majority of bacterial surface glycans are decorated with diverse rare functional groups, including amido, acetamidino, carboxamido and pyruvate groups. These functional groups are thought to be important constituents for the biological activities of glycans. Chemical synthesis of glycans bearing these functional groups or their variants is essential for the investigation of structure-activity relationships by a medicinal chemistry approach. To date, a broad choice of synthetic methods is available for targeting the different rare functional groups in bacterial surface glycans. This article reviews the structures of naturally occurring rare functional groups in bacterial surface glycans, and the chemical methods used for installation of these groups.
Bacterial Infections ; Humans ; Polysaccharides/chemistry* ; Structure-Activity Relationship

For the purpose of seeking new antibiotics, researchers usually modify the already-existing ones. However, this strategy has been extensively used and is close to its limits, especially in the case of aminoglycosides, and it is difficult to find a proper aminoglycoside antibiotic for novel modification. In this paper, we reported the design, synthesis, and evaluation of a series of 5-epi-neamine derivatives based on the structural information of bacterial 16S RNA A-site binding with aminoglycosides. Bioassay results showed that our design strategy was feasible. Our study offers a new way to search for structurally novel aminoglycosides. Meanwhile, our study provides valuable structure-activity relationship information, which will lead to better understanding and exploitation of the drug target, and improved development of new aminoglycoside antibiotics.
Aminoglycosides/chemistry* ; Anti-Bacterial Agents/chemistry* ; RNA, Ribosomal, 16S/metabolism* ; Structure-Activity Relationship ; Biological Assay