Alzheimer\'s disease (AD) is a progressive neurodegenerative disorder marked by the accumulation of amyloid-beta plaques and hyperphosphorylated tau proteins, leading to cognitive decline and neuronal death. However, despite extensive research, there are still no effective treatments for this condition. In this study, a series of chloride-substituted Ramalin derivatives is synthesized to optimize their antioxidant, anti-inflammatory, and their potential to target key pathological features of Alzheimer\'s disease. The effect of the chloride position on these properties is investigated, specifically examining the potential of these derivatives to inhibit tau aggregation and beta-site amyloid precursor protein cleaving enzyme 1 (BACE-1) activity. Our findings demonstrate that several derivatives, particularly RA-3Cl, RA-4Cl, RA-26Cl, RA-34Cl, and RA-35Cl, significantly inhibit tau aggregation with inhibition rates of approximately 50%. For BACE-1 inhibition, Ramalin and RA-4Cl also significantly decrease BACE-1 expression in N2a cells by 40% and 38%, respectively, while RA-23Cl and RA-24Cl showed inhibition rates of 30% and 35% in SH-SY5Y cells. These results suggest that chloride-substituted Ramalin derivatives possess promising multifunctional properties for AD treatment, warranting further investigation and optimization for clinical applications.

Fibrosis leads to organ failure and death, which is the final stage of many chronic diseases. Triptolide (TPL) is a terpenoid extracted from the traditional Chinese medicine Tripterygium wilfordii Hook. F (TwHF). Triptolide and its derivatives (Omtriptolide, Minnelide, (5R)-5-hydroxytriptolide) have been proven to have a variety of pharmacological effects. This study comprehensively reviewed the antifibrotic mechanism of TPL and its derivatives, and discussed the application of advanced nanoparticles (NPs) drug delivery system in the treatment of fibrotic diseases by TPL. The results show that TPL can inhibit immune inflammatory response, relieve oxidative stress and endoplasmic reticulum stress (ERS), regulate collagen deposition and inhibit myofibroblast production to play an anti-fibrosis effect and reduce organ injury. A low dose of TPL has no obvious toxicity. Under pathological conditions, a toxic dose of TPL has a protective effect on organs. The emergence of TPL derivatives (especially Minnelide) and NPs drug delivery systems promotes the anti-fibrosis effect of TPL and reduces its toxicity, which may be the main direction of anti-fibrosis research in the future.

In order to develop antiviral drugs, we utilized pterodontic acid (Poa-1) as a lead compound and conducted various modifications, including oxidation, reduction, addition, esterification, and acylation, resulting in the synthesis of 29 derivatives, of which 25 were novel acylation derivatives. Cell-level validation demonstrated that 4 derivatives exhibited significant inhibitory effects on the influenza A virus (H1N1), with an IC50 = 4.04-36.13 μM. Notably, four acylation derivatives (compounds IIE5, IIE6, IIE9, and IIE17) exhibited specific antiviral activities against influenza A virus (H1N1) with low cytotoxicity, indicating favorable therapeutic indices (SI = 3.5-11.9). Structure-activity relationship studies indicated that C5-C6 olefins are essential groups for antiviral activity, C11-C12 conjugated olefins will not interfere with antiviral activity. Carboxylic acid is an essential group for activity. Moreover，Carboxylic acid acylation can improve antiviral activity, and the inclusion of guanidine, cyclic amine, and phenyl groups with electron-donating substituents could enhance the antiviral activity of the lead compound. Natural products structural modifications are capable of improving the biological activity of lead compounds, offering a rapid pathway for the development of potent new structures.

Brain-derived neurotrophic factor (BDNF) and its downstream tropomyosin receptor kinase B (TrkB) signaling pathway play pivotal roles in the resilience and action of antidepressant drugs, making them prominent targets in psychiatric research. Oxidative stress (OS) contributes to various neurological disorders, including neurodegenerative diseases, stroke, and mental illnesses, and exacerbates the aging process. The nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant responsive element (ARE) serves as the primary cellular defense mechanism against OS-induced brain damage. Thus, Nrf2 activation may confer endogenous neuroprotection against OS-related cellular damage; notably, the TrkB/phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) pathway, stimulated by BDNF-dependent TrkB signaling, activates Nrf2 and promotes its nuclear translocation. However, insufficient neurotrophin support often leads to the downregulation of the TrkB signaling pathway in brain diseases. Thus, targeting TrkB activation and the Nrf2-ARE system is a promising therapeutic strategy for treating neurodegenerative diseases. Phytochemicals, including indole-3-carbinol (I3C) and its metabolite, diindolylmethane (DIM), exhibit neuroprotective effects through BDNF\'s mimetic activity; Akt phosphorylation is induced, and the antioxidant defense mechanism is activated by blocking the Nrf2-kelch-like ECH-associated protein 1 (Keap1) complex. This review emphasizes the therapeutic potential of I3C and its derivatives for concurrently activating neuronal defense mechanisms in the treatment of neurodegenerative diseases.

In modern cancer therapy, blockage of more than one target is a standard approach, and there are already many dual-target drugs that can achieve multiple inhibition through a single molecule. Herein, we designed and synthesized a series of novel derivatives with signal transducer and activator of transcription 3 (STAT3) and histone deacetylase (HDAC) inhibitory activity through strategy of combining pharmacophore based on the STAT3 inhibitor E28 and HDAC inhibitor MS-275. Among them, compound 24 (IC50 = 8.22 ± 0.27 μM) showed better anti-tumor activity than the clinical Class I HDAC inhibitor MS-275 (IC50 = 14.65 ± 0.24 μM) in MCF-7 breast cancer cells. Furthermore, the dual inhibition to HDAC and STAT3 of compound 24 was validated by western blot analysis. The study provides new tool compounds for further exploration of STAT3-HDAC pathway inhibitor achieved with a single molecule.

Biomass and its derivatives have broad applications in the fields of bio-catalysis, energy storage, environmental remediation. The structure and components of biomass, which are vital parameters affecting corresponding performances of derived products, need to be fully understood for further regulating the biomass and its derivatives. Herein, tobacco is taken as an example of biomass to introduce the typical characterization techniques in unraveling the structural information, chemical components, and properties of biomass and its derivatives. Firstly, the structural information, chemical components and application for biomass are summarized. Then the characterization techniques together with the resultant structural information and chemical components are introduced. Finally, to promote a wide and deep study in this field, the perspectives and challenges concerning structure and composition charaterization in biomass and its derivatives are put forward.

Chalcones are a group with recognized biological potential against many diseases, including cancer. Thus, studies on these structure have become an attractive chemical strategy to optimize their biological activities. One of the synthetic routes used to obtain chalcone derivatives is esterification using either commercial acid chlorides or carboxylic acids. This work focuses on preparing chalcone derivatives and investigating their biological potential against cancer cells. Compound 1 was synthetized by Claisen-Schmidt condensation followed by esterification of the 3\'-OH, resulting in eight compounds named 1a-b and 2a-f. All structures were confirmed by 1H and 13C NMR and FT-IR, and cytotoxicity was evaluated in the HCT 116 (colon adenocarcinoma), MCF-7 (breast adenocarcinoma), and CCD-18Co (nontumoral colon fibroblasts) cell lines. Chalcone derivatives were generally more active toward the colon cancer cell line, and 1a and 2b were selected for IC50 determination, presenting IC50 values of approximately 10 μM in HCT 116 cells and above 20 μM in both MCF7 and CDC-18-Co cells, suggesting moderate selectivity. Additionally, we tested compounds 1a and 2b in combination with doxorubicin, but they did not act synergistically with this anthracycline. In conclusion, considering these compounds obtained by the esterification reaction, 1a and 2d showed better results against cytotoxic cells.

This study investigated environmental distribution and human exposure of polycyclic aromatic hydrocarbons (PAHs) and their derivatives in one Chinese petroleum refinery facility. It was found that, following with high concentrations of 16 EPA PAHs (∑Parent-PAHs) in smelting subarea of studied petroleum refinery facility, total derivatives of PAHs [named as XPAHs, including nitro PAHs (NPAHs), chlorinated PAHs (Cl-PAHs), and brominated PAHs (Br-PAHs)] in gas (mean= 1.57 × 104 ng/m3), total suspended particulate (TSP) (mean= 4.33 × 103 ng/m3) and soil (mean= 4.37 × 103 ng/g) in this subarea had 1.76-6.19 times higher levels than those from other subareas of this facility, surrounding residential areas and reference areas, indicating that petroleum refining processes would lead apparent derivation of PAHs. Especially, compared with those in residential and reference areas, gas samples in the petrochemical areas had higher ∑NPAH/∑PAHs (mean=2.18), but lower ∑Cl-PAH/∑PAHs (mean=1.43 × 10-1) and ∑Br-PAH/∑PAHs ratios (mean=7.49 × 10-2), indicating the richer nitrification of PAHs than chlorination during petrochemical process. The occupational exposure to PAHs and XPAHs in this petroleum refinery facility were 24-343 times higher than non-occupational exposure, and the ILCR (1.04 × 10-4) for petrochemical workers was considered to be potential high risk. Furthermore, one expanded high-resolution screening through GC Orbitrap/MS was performed for soils from petrochemical area, and another 35 PAHs were found, including alkyl-PAHs, phenyl-PAHs and other species, indicating that profiles and risks of PAHs analogs in petrochemical areas deserve further expanded investigation.

Treating cancer remains challenging due to the substantial side effects and unfavourable pharmacokinetic characteristics of antineoplastic medications, despite the progress made in comprehending the properties and actions of tumour cells in recent years. The advancement of biomaterials, such as stents, implants, personalised drug delivery systems, tailored grafts, cell sheets, and other transplantable materials, has brought about a significant transformation in healthcare and medicine in recent years. Gelatin is a very adaptable natural polymer that finds extensive application in healthcare-related industries owing to its favourable characteristics, including biocompatibility, biodegradability, affordability, and the presence of accessible chemical groups. Gelatin is used as a biomaterial in the biomedical sector for the creation of drug delivery systems (DDSs) since it may be applied to various synthetic procedures. Gelatin nanoparticles (NPs) have been extensively employed as carriers for drugs and genes, specifically targeting diseased tissues such as cancer, tuberculosis, and HIV infection, as well as treating vasospasm and restenosis. This is mostly due to their biocompatibility and ability to degrade naturally. Gelatins possess a diverse array of potential applications that require more elucidation. This review focuses on the use of gelatin and its derivatives in the diagnosis and treatment of cancer. The advancement of biomaterials and bioreactors, coupled with the increasing understanding of emerging applications for biomaterials, has enabled progress in enhancing the efficacy of tumour treatment.