Aconitum carmichaelii Debx. exhibits overwhelming efficacy against heart failure, inflammation and pain, but its clinical application is limited by concomitant cardiotoxicity and neurotoxicity. Aconitine (AC), the most abundant bioactive alkaloid, has narrow therapeutic window, with well-defined toxic and therapeutic thresholds. However, the overlapping molecular targets mediating dual toxicity and efficacy of AC remain poorly characterized.

This study aimed to evaluate dual pharmacological and toxicological roles of AC through integrative pharmacology and transgenic mouse models.

The overlapping targets of AC-related toxicity/efficacy were identified based on integrative pharmacology. By generating Cyp3a-/- transgenic mice expressing human CYP3A4 (hCYP3A4), Ugt1, P-gp, Mrp2, BCRP, and Nrf2 knockout mice, the effects of AC on toxicity, pain, inflammation, and heart failure were assessed.

We identified 143 overlapping targets predominantly enriched in metabolic pathways. Symptom-based toxicity scores were strikingly elevated in AC-exposed hCYP3A4, Mrp2-/-, P-gp-/-, BCRP-/-, and Nrf2-/- mice compared to WT mice. Additionally, AC prolonged the latency of response by approximately 18s, 15s, 14s, and 5s, respectively, in hCYP3A4, Mrp2-/-, P-gp-/-, and Nrf2-/- mice by hot plate assay. Interestingly, both toxicity score and analgesic latency initially increased and subsequently decreased, peaking at 60 min. AC obviously decreased the acetic acid-induced writhing and permeability by 45.7% and 22.2% in hCYP3A4 mice, whereas these changes were amplified in Mrp2-/- mice compared to WT mice. Furthermore, AC attenuated DOX induced heart failure in hCYP3A4 mice, with an effective rate of 20.9%, with Septin4 implicated in AC-related metabolism.

Metabolic targets may elucidate the mechanistic overlap between the toxicity and efficacy of AC. Notably, hCYP3A4 exhibited heightened toxicity, alongside enhanced analgesic, anti-inflammatory, and cardioprotective effects. Our findings position metabolic pathways as critical nodes for AC-related dual effect, and establish Septin4 as a candidate mediator of its metabolic regulation.

Seven new aconitine-type C19-diterpenoid alkaloids, apetaldines K-Q (1-7), were isolated from the roots of Aconitum apetalum (Huth) B. Fedtsch. Their structures were established on the basis of extensive spectroscopic analyses (HRESIMS, 1D and 2D NMR). Among them, compounds 1 and 2 possess a unique 2-(E)-(2-methylbut-2-enamido)benzoate moiety at the C-18 position. Furthermore, cytotoxic activities of these diterpenoid alkaloids were also evaluated.

The current standard treatment for ovarian cancer consists of surgery to reduce the size of the tumor, followed by treatment with chemotherapeutic drugs, which have major side effects. Therefore, finding a new natural product drug with fewer side effects is a strategy. Delphinium brunonianum (D. brunonianum) is a traditional Tibetan medicine, mainly from southern Tibet, China, whereas the chemical constituents in this plant remain elusive. The major metabolites in the dichloromethane fraction of D. brunonianum were analyzed and purified by HPLC and various column chromatography techniques. Nine diterpenoid alkaloids (1-9) and one amide alkaloid (10) were isolated from D. brunonianum, including three novel C19-type diterpenoid alkaloids (Brunonianines D-F) (1-3). Their structures were elucidated by 1D/2D NMR, HR-ESI-MS and single-crystal X-ray diffraction analyses. All compounds were evaluated for toxicity in four tumor cell lines. Most of the compounds exhibited potent inhibitory effects on Skov-3 cell lines, with IC50 values ranging from 2.57 to 8.05 μM. The western blotting experiment was used to further analyze the expression levels of molecules in the Bax/Bcl-2/Caspase-3 signaling pathway for compound 1. Molecular docking was performed to predict the binding modes of Brunonianine D with target proteins. In vivo experiments were also performed and evaluated in real time by monitoring the size of the Skov-3 tumor. Additionally, tumor H&E staining and the TUNEL assay used to evaluate anti-tumor effects.

Terpenoid alkaloids are recognized as a class of compounds with limited numbers but potent biological activities, primarily derived from plants, with a minor proportion originating from animals and microorganisms. These alkaloids are synthesized from the same prenyl unit that forms the terpene skeleton, with the nitrogen atom introduced through β-aminoethanol, ethylamine, or methylamine, leading to a range of complex and diverse structures. Based on their skeleton type, they can be categorized into monoterpenes, sesquiterpenes, diterpenes, and triterpene alkaloids. To date, 289 natural terpenoid alkaloids, excluding triterpene alkaloids, have been identified in studies published between 2019 and 2024. These compounds demonstrate a spectrum of biological activities, including anti-inflammatory, antitumor, antibacterial, analgesic, and cardioprotective effects, making them promising candidates for further development. This review provides an overview of the sources, chemical structures, and biological activities of natural terpenoid alkaloids, serving as a reference for future research and applications in this area.

A series of novel N-aryl-debenzeyldonepezil derivatives (1-26) were designed and synthesized as cholinesterase inhibitors by the modification of anti-Alzheimer's disease drug donepezil, using Palladium catalyzed Buchwald-Hartwig cross-coupling reaction as a key chemical synthesis strategy. In vitro cholinesterase inhibition studies demonstrated that the majority of synthesized compounds exhibited high selective inhibition of AChE. Among them, analogue 13 possessing a quinoline functional group showed the most potent AChE inhibition effect and significant neuroprotective effect against H2O2-induced injury in SH-SY5Y cells. Furthermore, Compound 13 did not show significant cytotoxicity on SH-SY5Y. These results suggest that 13 is a potential multifunctional active molecule for treating Alzheimer's disease.

A series of arylated huperzine A (HPA) derivatives (1-24) were efficiently synthesized in good yields (45-88% yields) through the late-stage modification of structurally complex natural anti-Alzheimer's disease (AD) drug huperzine A (HPA), using the palladium-catalyzed Suzuki-Miyaura cross-coupling reaction. The acetylcholinesterase (AChE) inhibitory activity of all synthesized compounds was evaluated to screen the potential anti-AD bioactive molecules. The results showed that introducing the aryl groups to C-1 position of HPA resulted in the unsatisfactory AChE inhibitory activity. The present study demonstrably verifies pyridone carbonyl group could be the necessary and unchangeable pharmacophore for maintaining HPA's anti-AChE potency, and provides the helpful information on the further research for developing anti-AD HPA analogues.

A series of novel myrsinane-type Euphorbia diterpene derivatives (1-37) were synthesized from the abundant natural lathyrane-type Euphorbia factor L3, using a multi-step chemical process guided by a bioinspired skeleton conversion strategy, with the aim of discovering potential anti-Alzheimer's disease (AD) bioactive lead compounds. The synthesis process involved a concise reductive olefin coupling reaction through an intramolecular Michael addition with a free radical, followed by a visible-light-triggered regioselective cyclopropane ring-opening. The cholinesterase inhibitory and neuroprotective activities of the synthesized myrsinane derivatives were evaluated. Most of the compounds showed moderate to strong potency, highlighting the importance of ester groups in Euphorbia diterpene. In particular, derivative 37 displayed the most potent acetylcholinesterase (AChE) inhibition, with an IC50 value of 8.3 μM, surpassing that of the positive control, tacrine. Additionally, 37 also showed excellent neuroprotective effect against H2O2-induced injury in SH-SY5Y cells, with a cell viability rate of 124.2% at 50 μM, which was significantly higher than that of the model group (viability rate 52.1%). Molecular docking, reactive oxygen species (ROS) analysis, immunofluorescence, and immunoblotting were performed to investigate the mechanism of action of myrsinane derivative 37. The results indicated that derivative 37 may be a promising myrsinane-type multi-functional lead compound for the treatment of Alzheimer's disease. Furthermore, a preliminary SAR analysis was performed to study the acetylcholinesterase inhibitory and neuroprotective activities of these diterpenes.

(-)-Adenophorone (1), a caged polycyclic sesquiterpene featuring an unprecedented tricyclo[4.3.1.05,9 ]decane skeleton, was isolated from Eupatorium adenopharum Spreng. The structure of 1 was unambiguously established by a combination of spectroscopic analysis, X-ray crystallography, and bioinspired total synthesis. Key synthetic features include a sequential Reformatsky/oxidation/regio- and stereoselective hydrogenation, and subsequent merged MBH-Tsuji-Trost cyclization. The concise synthetic sequence efficiently constructs the bicyclic skeleton of cadinene sesquiterpene (+)-euptox A (2) in 8 steps from commercially available monoterpene (-)-carvone (6), with outstanding performance on diastereocontrol. The bioinspired synthesis of 1 was achieved from 2, a plausible biogenetic precursor, via transannular Michael addition. This work provides experimental evidence of our proposed biosynthetic hypothesis of 1. Additionally, compound 1 showed potent neuroprotective activity in H2 O2 -treated SH-SY5Y and PC12 cells.

This study provides a narrative review of diterpenoid alkaloids (DAs), a family of extremely important natural products found predominantly in some species of Aconitum and Delphinium (Ranunculaceae). DAs have long been a focus of research attention due to their numerous intricate structures and diverse biological activities, especially in the central nervous system (CNS). These alkaloids originate through the amination reaction of tetra or pentacyclic diterpenoids, which are classified into three categories and 46 types based on the number of carbon atoms in the backbone structure and structural differences. The main chemical characteristics of DAs are their heterocyclic systems containing β-aminoethanol, methylamine, or ethylamine functionality. Although the role of tertiary nitrogen in ring A and the polycyclic complex structure are of great importance in drug-receptor affinity, in silico studies have emphasized the role of certain sidechains in C13, C14, and C8. DAs showed antiepileptic effects in preclinical studies mostly through Na⁺ channels. Aconitine (1) and 3-acetyl aconitine (2) can desensitize Na⁺ channels after persistent activation. Lappaconitine (3), N-deacetyllapaconitine (4), 6-benzoylheteratisine (5), and 1-benzoylnapelline (6) deactivate these channels. Methyllycaconitine (16), mainly found in Delphinium species, possesses an extreme affinity for the binding sites of α7 nicotinic acetylcholine receptors (nAChR) and contributes to a wide range of neurologic functions and the release of neurotransmitters. Several DAs such as bulleyaconitine A (17), (3), and mesaconitine (8) from Aconitum species have a drastic analgesic effect. Among them, compound 17 has been used in China for decades. Their effect is explained by increasing the release of dynorphin A, activating the inhibitory noradrenergic neurons in the β-adrenergic system, and preventing the transmission of pain messages by inactivating the Na⁺ channels that have been stressed. Acetylcholinesterase inhibitory, neuroprotective, antidepressant, and anxiolytic activities are other CNS effects that have been investigated for certain DAs. However, despite various CNS effects, recent advances in developing new drugs from DAs were insignificant due to their neurotoxicity.

A series of new N-aryl galantamine analogues (5a-5x) were designed and synthesized by modification of galantamine, using Pd-catalyzed Buchwald-Hartwig cross-coupling reaction in good to excellent yields. The cholinesterase inhibitory and neuroprotective activities of N-aryl derivatives of galantamine were evaluated. Among the synthesized compounds, the 4-methoxylpyridine-galantamine derivative (5q) (IC₅₀ = 0.19 μM) exhibited excellent acetylcholinesterase inhibition activity, as well as significant neuroprotective effect against H₂O₂-induced injury in SH-SY5Y cells. Molecular docking, staining, and Western blotting analyses were performed to demonstrate the mechanism of action of 5q. Derivative 5q would be a promising multifunctional lead compound for the treatment of Alzheimer's disease.

The weevil Pimelocerus perforatus poses a serious pest problem for olive cultivation in Japan. Two new racemic fluorescent benzoxazines, designated as pimeforazine A ((±)-1) and pimeforazine B ((±)-2), were successfully isolated from P. perforatus. Their structures, including the absolute configurations of their resolved enantiomers, were determined using spectroscopic methods, single-crystal X-ray diffraction, and electronic circular dichroism calculations. The neuroprotective activity of the isolated compounds was evaluated against hydrogen peroxide-induced cellular damage in SH-SY5Y human neuroblastoma cells. Compounds (±)-1 and (±)-2 exhibited neuroprotective effects.

The C₁₈-diterpenoid alkaloid lappaconitine (LA) is a non-addictive analgesic used in China. The toxicity (LD₅₀ = 11.7 mg/kg) limits its application. Two series of LA derivatives, including amides and sulfonamides (1-93), were designed and synthesized by modification on their C4 acetamidobenzoate side chains in this work. In vivo analgesic activity and toxicity of all derivatives were evaluated, and the structure-activity relationship was summarized. Six lead compounds (35, 36, 39, 49, 70, and 89) exhibited approximate analgesic activity to LA but with significantly reduced toxicity. The therapeutic index of these compounds is 14-30 times that of LA. In vivo metabolism study of the lead compounds 39, 49, 70, and 89 were conducted by UPLC-MS^E, indicating the reason for the low toxicity of the potential derivatives might be they are difficult to metabolize to toxic metabolite N-deacetyllappaconitine compared to LA. The effects of lead compounds on sodium channels and hERG channels were also studied by ion channel reader (ICR) which further revealed their analgesic and toxicity-attenuating mechanisms. Sodium channel assay revealed that the analgesic mechanism of these lead compounds was inhibiting the Na_v 1.7 channels. Taken together, compound 39 was provided as a new analgesic lead compound with significantly low toxicity and comparable activity to LA.

Two new lappaconitine-type C18-diterpenoid alkaloids, named as leucostosines C (1) and D (2), together with six known compounds (3-8), were isolated from the roots of Aconitum leucostomum Worosch. Their structures were elucidated by various spectroscopic analyses, including IR, HR-ESI-MS, NMR spectra and X-ray experiments. Leucostosine C is the first diterpenoid alkaloid bearing the 7-amino group. The isolated compounds were tested for the acetylcholinesterase (AChE) inhibitory effect and neuroprotective activity, none of them showed significant activities.

Yunaconitine (YAC), crassicauline A (CCA), 8-deacetylyunaconitine (DYA), and 8-deacetylcrassicauline A (DCA), as hidden toxic Aconitum alkaloids, are detected in some products of processed Aconitum carmichaelii lateral root and poisoning cases. The distribution and toxicity of these four components in Aconitum herbs should be further systematically studied for medication safety. This study developed a new UHPLC-QQQ-MS/MS method to determine ten Aconitum alkaloids, including aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine, benzoylhypaconine, YAC, CCA, DYA, and DCA, for Aconitum herbs simultaneously. YAC and CCA were founded in some samples of unprocessed A. carmichaelii lateral root (7.04%), A. carmichaelii root (9.43%), A. brachypodum root (6.00%), and A. ouvrardianum root (100%). Four hidden toxic Aconitum alkaloids were detected in processed A. carmichaelii lateral root (2.56%) and A. vilmorinianum root (100%). Four hidden toxic Aconitum alkaloids played significant roles in the classification of Aconitum herbs by OPLS-DA analysis. The acute toxicity test was performed by up-and-down procedure (UDP). The oral administration of the half lethal dose (LD₅₀) of YAC, CCA, DYA, and DCA to female ICR mice was 2.37 mg/kg, 5.60 mg/kg, 60.0 mg/kg, and 753 mg/kg, respectively. The LD₅₀ by intravenous injection was 0.200 mg/kg, 0.980 mg/kg, 7.60 mg/kg, and 34.0 mg/kg, respectively. The LD₅₀ of unprocessed A. carmichaelii lateral root, A. vilmorinianum root, and A. brachypodum root to mice orally was 1.89 g/kg, 0.950 g/kg, and 0.380 g/kg, respectively. Symptoms of Aconitum alkaloid poisoning in mice were decreased activity, fur erect, palpebral edema, vomiting, polypnea, and convulsions. The main change of organs was flatulence. No poisoning or death occurred in mice at the maximum dosage (27.0 g/kg) of A. ouvrardianum root orally. To better control the quality and safety of Aconitum herbs, this study provides favorable support for improving the existing standards to strengthen the supervision of the four hidden toxic Aconitum alkaloids.

This review systematically summarizes the C18-diterpenoid alkaloid (DA) compositions isolated from the genera Aconitum and Delphinium in the Delphineae tribe (Ranunculaceae). A total of 117 distinct C18-DA components have been reported, including 58 lappaconitine-type DAs, 54 ranaconitine-type DAs, and five rearranged-type DAs. These components mainly originated from plants from the subgenus Lycoctonum in the genus Aconitum or less frequently from plants within the genus Delphinium. Natural C18-DAs have exhibited a wide range of bioactivities, including analgesic, antiarrhythmic, anti-inflammatory, anti-tumor, and insecticidal activities, which are closely related to their chemical structures. The high chemical and biological diversities among the reported C18-DA constituents in Delphineae plants indicated their potential as a vast resource for drug discovery. Additionally, the Delphineae plant C18-DAs exhibited chemotaxonomic values and showed a high regularity of distribution at different taxonomic levels; therefore, the Delphineae plant C18-DAs can serve as good chemical molecular markers in the taxonomic treatment of plants within this tribe, especially in the infrageneric division.

Bioprivileged molecules hold great promise for supplementing petrochemicals in sustainable organic synthesis of a diverse bioactive products library. Secologanin, a biorenewable monoterpenoid glucoside with unique structural elements, is the key precursor for thousands of natural monoterpenoid alkaloids. Inspired by its inherent highly congested functional groups, a secologanin-based diversity-oriented synthesis (DOS) strategy for novel pseudo-natural alkaloids was developed. All the reactive units of secologanin were involved in these operation simplicity protocols under mild reaction conditions, including the one-step enantioselective transformation of exocyclic C8, C8/C11, and C8/C9/C10 as well as the chemoenzymatic manipulation of endocyclic C2/C6 via the attack by various nucleophiles. A combinatory scenario of the aforementioned reactions further provided diverse polycyclic products with multiple chiral centers. Preliminary activity screening of these newly constructed molecules led to the discovery of antimalarial and highly potent neuroprotective skeletons. The application of green biorenewable secologanin in diversity-oriented pseudo-natural monoterpenoid alkaloid synthesis might encourage the pursuit of valuable bioactive frameworks.

In the current study a late-stage diversification of unactivated olefins labd-8(17)-en-15-oic acid (1a) and methyl labd-8(17)-en-15-oate (1b) via Heck-Matsuda arylation is described. The reaction provided straightforward and practical access to a series of novel aryl-labdane-type derivatives (HM adducts 3a-h) in moderate to good yields in a highly regio- and stereoselective manner at room temperature under air atmosphere. The cytotoxic activity of these compounds was investigated in vitro against three different human cell lines (THP-1, K562, MCF-7). Of these, HM adduct 3h showed a selective effect in all cancer cell lines tested and was selected for extended biological investigations in a leukemia cell line (K562), which demonstrated that the cytotoxic/antiproliferative activity observed in this compound might be mediated by induction of cell cycle arrest at the sub-G1 phase and by autophagy-induced cell death. Taken together, these findings indicate that further investigation into the anticancer activity against chronic myeloid leukemia from aryl-labdane-type derivatives may be fruitful.

Covering: 77 A.D. up to 2020Norditerpenoid alkaloids (NDA), typically N-ethylpiperidine containing C19 or C18 natural product diterpenes, are hexacycles with several contiguous often oxygenated stereocentres. As a function of their structural complexity, they display important pharmacological activities. The processed plants are used as important folk drugs and four NDAs have now been clinically approved. Many metabolism studies on Aconitum alkaloids have been reported as the understanding of their biotransformation in living systems and in cell-free systems is important for the development of these alkaloids as drugs. This Highlight sets out the missing links in NDA biosynthesis, their biological applications, SAR, toxicity, metabolism, and analytical studies.

Lead compound is an important concept for modern drug discovery. In this study, a new concept of lead chemome and an efficient strategy to discover lead chemome were proposed. Compared with the concept of lead compound, lead chemome can provide not only the starting point for drug development, but also the direction for structure optimization. Two traditional Chinese medicines of Mahonia bealei and Mahonia fortunei were used as examples to illustrate the strategy. Based on natural chromatogram-effect correlation (NCEC), berberine, palmatine and jatrorrhizine were discovered as acetylcholinesterase (AchE) inhibitors. Taking the three compounds as template molecules, a lead chemome consisting of 10 structurally related natural compounds were generated through natural structure-effect correlation (NSEC). In the lead chemome, the IC₅₀ values of jatrorrhizine, berberine, coptisine, palmatine and epiberberine are at nanomolar level, which are comparable to a widely used drug of galantamine. Pharmacophore modeling shows that the positive ionizable group and aromatic rings are important substructures for AchE inhibition. Molecular docking further shows that pi-cation interaction and pi-pi stacking are critical for compounds to maintain nanomolar IC₅₀ values. The structure-activity information is helpful for drug design and structure optimization. This work also expanded the traditional understanding of "stem is the medicinal part of Mahonia bealei and Mahonia fortunei". Actually, all parts except the leaf of Mahonia bealei exhibited potent AchE-inhibitory activity. This study provides not only a strategy to discover lead chemome for modern drug development, but also a reference for the application of different parts of medicinal plants.

The first systematic direct diversification of a complex natural product by metal-catalyzed N-H functionalization was carried out. A new series of N-(hetero)aryl analogues (1-32) of the natural anti-Alzheimer's disease drug huperzine A (HPA) was prepared via palladium-catalyzed Buchwald-Hartwig cross-coupling reactions of HPA with various aryl bromides in good yields. Most of the N-aryl-huperzine A (N-aryl-HPA) analogues showed good acetylcholinesterase (AChE) inhibitory activity in in vitro experiments. Three arylated huperzine A analogues (14, 19, and 30) exhibited stronger anti-AChE activity than HPA. The 5-methoxy-2-pyridyl analogue (30) displayed the most potent AChE inhibition activity, with an IC₅₀ value of 1.5 μM, which was 7.6-fold more active than HPA. Compound 30 also exhibited better neuroprotective activity for H₂O₂-induced damage in SH-SY5Y cells than HPA. Structure-activity relationship analysis suggested that the electron density of the installed aromatic ring or heteroaromatic ring played a significant role in inducing the AChE inhibition activity. Overall, compound 30 showed the advantages of easy synthesis, high potency and selectivity, and improved neuroprotection, making it a potential huperzine-type lead compound for Alzheimer's disease drug development.

Three new aconitine-type C₁₉-diterpenoid alkaloid namely novolunines A (1), B (2), and C (3), along with fifteen known diterpenoid alkaloids were isolated from the roots of Aconitum novoluridum, whose phytochemical investigations have never been reported before. The structures of three new alkaloids were established on the basis of spectra data (high-resolution electrospray ionization (HR-ESI)-MS, IR, one dimensional (1D)- and 2D-NMR). Noteworthily, novolunines A (1) and B (2) are two diterpenoid alkaloids bearing conformational isomerism. In addition, the diterpenoid alkaloids 1-3 did not show any anti-acetylcholinesterase (AChE) or anti-inflammatory activities.