Oxidative stress has been confirmed to be closely related to the occurrence and development of pulmonary fibrosis (PF). The Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid-2 related factor 2 (Nrf2) pathway plays a key role in maintaining cellular redox homeostasis. Targeting the Keap1 protein to activate Nrf2 could be a promising strategy for treating PF. Virtual screening via a pharmacophore model was used to screen candidate compounds with potential Keap1 binding ability from the U.S. Food and Drug Administration (FDA) database. The results revealed that sodium cromoglycate (Cro) has the highest fit value and absolute docking score and could improve the thermal stability of the Keap1 protein in a CETSA, confirming that Cro could bind to the Keap1 protein directly. Further studies revealed that Cro promoted Nrf2 translocation into the nucleus, relieved oxidative stress, prevented the epithelial-mesenchymal transition (EMT) process and upregulated fibrosis markers in TGF-β1-induced A549 cells, indicating that Cro has anti-pulmonary fibrosis activity in an in vitro lung fibrosis model. Moreover, in a mouse model of bleomycin (BLM)-induced pulmonary fibrosis, Cro administration improved pulmonary fibrosis, activated Nrf2 signaling, and blocked the EMT process. In summary, these results demonstrated that Cro could activate Nrf2 signaling to clear reactive oxygen species (ROS) by directly binding to Keap1 and alleviate pulmonary fibrosis by blocking the progression of EMT both in vitro and in vivo.

The PI3K/Akt pathway is crucial in numerous cellular functions such as cell growth, survival proliferation and movement in both normal and cancer cells. It plays also a key role in epithelial-mesenchymal transitions and angiogenesis during the tumorigenesis processes. Since many transformative events in cancer are driven by increased PI3K/Akt pathway signaling, Akt is considered a valuable target for developing new therapies against various tumor types, including pancreatic cancer. This is because the PI3K/AKT/mTOR pathway is a key downstream effector of RAS, and RAS activation is the most prominent genetic alteration in pancreatic cancer. Herein we report the synthesis and the biological evaluation of a new series of azole urea compounds that exhibited promising antiproliferative and antimigratory activities against pancreatic cancer cells through an Akt inhibition mechanism. These effects were demonstrated using a variety of assays, including Sulforhodamine B, cell-cycle, wound-healing, and kinase activity, apotposis and ELISA assays. Additionally, the anticancer properties of the most active compound in the series were confirmed in the 3D spheroid model of PATU-T cells.

The axial complex of Sn(IV)-tetra(4-sulfophenyl)porphyrin (SnP) with Rose Bengal (RB) was obtained where RB axial binding is realized through the hydroxyl groups of the xanthene dye [SnP(RB)]. The luminescent properties of the SnP(RB) (fluorescence and ability to generate singlet oxygen at room temperature) in aqueous media with additives of surfactant cetylpyridinium chloride (CPC) and ε-poly-l-lysine (EPL) were studied. It was found that nature of the medium (surfactant additives of different concentrations) determines the effectiveness of the photoinduced energy transfer from the RB fragment to the SnP fragment of the hybrid fluorophore (HF). It has been established that the ability of the HF to generate singlet oxygen in DO and DO-micellar media is higher than that of its constituent fragments. The dark and photodynamic antibacterial activity of the HF against two microorganisms [Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus)] was determined and analyzed. It was shown how the antibacterial activity of the HF depends on the nature of the bacteria, the micellar environment and radiation dose.

Nowadays α-amylase is widely used in various fields. Therefore, in this study, the effects of neutral (T), negatively charged (T) and positively charged (T) peptides on α-amylase activity were investigated by means of an applied protein electric field, and spectroscopy and molecular dynamics were employed to investigate this mechanism. It was found that the nature of the charge of the peptides had a strong influence on α-amylase activity, with T and T increasing and decreasing α-amylase activity, respectively, whereas T had no effect on enzyme activity. Fluorescence spectroscopy and circular dichroism results indicated that the charged peptides changed the conformation of α-amylase. Meanwhile, the molecular dynamics results showed that the charged peptides changed the distribution of the surface charge of α-amylase mainly through electrostatic force, which not only changed the conformation of the enzyme, but also altered the microenvironment of the enzyme active centre, which caused α-amylase to become compact or loose to affect the enzyme activity.

Epigenetic-targeted therapy has been applied in the treatment of several types of cancer. Herein, based on the synergistic antitumor effects of co-targeting HDACs and EZH2 in some hematological malignancies, a novel series of tazemetostat-based HDACs/EZH2 dual inhibitors were rationally designed, synthesized, and biologically evaluated. Satisfyingly, compounds 22a and 22b were identified as potent HDACs/EZH2 dual inhibitors with robust antiproliferative activities against one diffuse large-cell B cell lymphomas (DLBCL) cell line harboring EZH2 mutation and multiple acute myeloid leukemia (AML) cell lines. Notably, after a short-term treatment in the EZH2 mutant DLBCL cell line (SU-DHL-6), 22a and 22b displayed much stronger antiproliferative activities than the approved EZH2 inhibitor tazemetostat, while after a long-term treatment in SU-DHL-6 cells, 22a and 22b displayed comparable or even superior antiproliferative activities to the approved HDACs inhibitor SAHA. In AML cells, compounds 22a and 22b displayed much more potent antiproliferative activities than tazemetostat, as well as distinctive differentiation-inducing abilities and superior apoptosis-inducing abilities relative to tazemetostat and SAHA. Moreover, the synergistic anti-AML effects of HDACs/EZH2 dual inhibitors combined with various anti-AML drugs were demonstrated.

This study aims to elucidate the anti-inflammatory mechanism of Peperomia pellucida (L.) Kunth in human retinal pigment epithelial cell line (ARPE-19) as stimulated by high glucose (34 mM and 68 mM), and advanced glycation end product (AGE) under different glucose (17 mM, 34 mM and 68 mM) environments via the nuclear factor kappa B (NF-κB) and peroxisome proliferator activated receptor gamma (PPAR-γ) signalling pathways. The cytotoxicity of P. pellucida in ARPE-19 cells was evaluated with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. The genes and proteins expression of nine pro-inflammatory, angiogenic and antioxidant markers, including glutathione peroxidase (GPx), interleukin 8, matrix metalloproteinase 2, monocyte chemoattractant protein 1, NF-κB, PPAR-γ, receptor for AGE (RAGE), soluble RAGE (sRAGE), and vascular endothelial growth factor in P. pellucida-treated ARPE-19 cells were compared to non-treated control via real-time polymerase chain reaction and western blot. Both P. pellucida methanolic extract (1.5 mg/mL and 3 mg/mL) and ethyl acetate fraction (4 mg/mL) were non-toxic to ARPE-19 cells and demonstrated cytoprotective effect against the high glucose (34 mM) and AGE (17 mM glucose)-induced cellular stress. High glucose and AGE activated the pro-inflammatory signalling in ARPE-19 cells, as evidenced by the increased NF-κB p65 phosphorylation, up-regulation of pro-inflammatory and angiogenic mediators (p<0.05) but reduced GPx, PPAR-γ and sRAGE protein expression. Both P. pellucida methanolic extract (3 mg/mL) and ethyl acetate fraction (4 mg/mL) suppressed (p<0.05) the pro-inflammatory and angiogenic markers expression under high glucose and AGE environment. The main phytochemicals identified in P. pellucida were dillapiole, 2,4,5-trimethoxystyrene, 9-octadecenoic acid, and pheophorbide A-methyl ester which displayed relatively strong binding affinity towards NF-κB p65 and PPAR-γ proteins in molecular docking analysis. This study has demonstrated that P. pellucida is a potential alternative anti-inflammatory source for managing diabetic retinopathy via NF-κB and PPAR-γ signalling.

The present study aimed to design and synthesize novel 6-N-benzyloxazolo[5,4-d]pyrimidin-7(6H)-imines 3a-j as possible inhibitors of the vascular endothelial growth factor receptor 2 (VEGFR2). The structures of newly synthesized compounds were confirmed via spectral and crystallographic data. NOESY spectroscopy was very useful in distinguishing between 6-N-benzyl-7(6H)-imine 3a and isomeric 7-N-benzyl-7-amine 4a, obtained by Dimroth rearrangement. Molecular docking at the VEGFR2 active site was performed, indicating that 7(6H)-imines should have a similar binding mode as type II VEGFR2 inhibitors. All derivatives were preliminary evaluated for in vitro cytotoxic activity against four human cancer cell lines, including lung cancer (A549), colorectal cancer (HT-29), melanoma (A375), breast cancer (MCF7), using tivozanib as a reference drug, and some of them were subjected to VEGFR2 inhibition, anti-angiogenic activity, and human serum albumin (HSA) binding assays. Only 6-N-2,4-dimethoxybenzyl derivative 3h appeared to be as active as tivozanib against all tested anticancer cell lines but equally toxic to healthy normal human dermal fibroblasts (NHDF). Derivatives 3f (6-N-2-methybenzyl) and 3b (6-N-4-methylbenzyl) have revealed slightly worse activity than 3h. They were cytotoxic agents comparable to tivozanib against three anticancer lines, but only 3b showed no cytotoxicity against NHDF. Both 3b and 3h proved to be effective VEGFR2 inhibitors with IC values comparable to that of tivozanib. Notably, 4a did not actually show an anticancer effect against the tested cancer lines, in contrast to isomeric 3a. In an angiogenesis assay, 3f and 3h significantly suppressed the tube formation ability of human dermal microvascular endothelial cells (HMEC-1), indicating their anti-angiogenic potential. The interactions between these compounds and HSA appeared to occur at two specific binding sites.

Novel hydroxamic acid and 3,6-amide modified α-mangostin derivatives were synthesized and evaluated their antiproliferative activities against KYSE 30 (esophageal cancer), HCT 116 (colon cancer), and HGC 27 (gastric cancer) cell lines. Most of the new derivatives displayed stronger anti-proliferative activities compared to α-mangostin. Among all the derivatives, compound 4a exhibited the most potent activity, with IC values of 0.57 ± 0.29 μM, 3.27 ± 0.16 μM, and 2.28 ± 1.02 μM against KYSE 30, HCT 116, and HGC 27 cells, respectively. Subsequent mechanism studies revealed that compound 4a inhibited cancer cells proliferation and colonies formation in a concentration-dependent manner. Additionally, compound 4a caused cell cycle arrest in a p53 dependent manner and induced apoptosis in p53 independent way. Meanwhile, 4a suppressed cell cycle related proteins (Cyclin D1 and cyclin B1) expression, increased pro-apoptotic proteins (cleaved PARP, cleaved caspase-7, and cleaved caspase-9) and decreased anti-apoptotic proteins (Bcl-2) expression. Moreover, 4a increased reactive oxygen species (ROS) levels in KYSE 30 cells and upregulated the expression of proteins related to the ROS related MAPK signaling pathway (p-ERK, p-p38, and p-JNK). These findings suggest that compound 4a holds promising potential as an antiproliferative agent by targeting MAPK signaling pathway to inhibit cell cycle progress, induce apoptosis and produce ROS in cancers.

This study provides a rapid and accurate method for screening steroid 5-alpha reductase (S5αR) inhibitors in Impatiens balsamina Linn (IB). using at-line LC-QTOF-ESI-MS/MS coupling S5αR inhibitory assay. IB (Balsaminaceae) is an annual herbaceous plant cultivated in tropical and subtropical regions. It has been used in traditional Chinese and Thai medicine for treatment of hair loss and various skin conditions, potentially through anti-androgenic mechanisms. A combined approach of S5αR inhibitory assay and LC-QTOF-ESI-MS/MS was developed to rapidly screen for target biomarkers and guide their isolation using preparative HPLC. The toxicity of both the extract and isolated biomarkers was evaluated on skin cells, keratinocytes, and fibroblasts. Eight bioactive compounds were identified as two naphthoquinone, two fatty acid derivatives, three nitrogenous compounds and one aromatic derivative. The most potent bioactive markers, identified as 2-methoxy-1,4-naphthoquinone (2MN) and impateinol, were targeted and isolated using preparative HPLC, yielding 5.0 % and 3.5 %, respectively. These compounds exhibited S5αR inhibitory activity higher than that of finasteride drug by 10 and 2 times, respectively. Both the isolated biomarkers and the extract demonstrated a broad therapeutic index. The developed method in this study proved to be both rapid and accurate, making it suitable for screening and targeting S5αR inhibitors in herbal plants or complex matrix samples. It facilitated the fast-guided isolation of bioactive compounds, highlighting its potential for future applications in drug discovery research.

A series of flavonol derivatives containing 1,2,4-triazole Schiff base was designed, synthesized and tested for their biological activities. The results of the biological activity test showed that compounds exhibited the obvious antifungal activities against Sclerotinia sclerotiorum (S.s), Rhizoctonia solani (R.s), Botrytis cinerea (B.c) and Phomopsis sp (P.s). Among them, K14 showed excellent antimicrobial activity against B.c with the half maximal effective concentration (EC) of 7.6 µg/mL as compared to azoxystrobin (18.0 µg/mL). Additionally, the in vivo protective and therapeutic activities of K14 on blueberry leaves were 94.1 and 88.7 % respectively, surpassing than that of the control drug azoxystrobin (91.6 and 74.4 %) at 200 µg/mL. The results of SEM showed that the mycelium appeared wrinkled, folded and changed in morphology after being treated with K14. In addition, fluorescence microscopy (FM) and cytoplasmic leakage assays showed that the cell membrane of B.c was disrupted. Further study of malondialdehyde (MDA) and relative conductivity measurements indicated that the normal function of cells is affected by K14 by increasing cell membrane permeability and promoting membrane lipid peroxidation. These results indicate that flavonol derivatives containing 1,2,4-triazole Schiff bases are expected to provide a new prospect for the development of novel fungicides.

Due to the multifactorial nature of Alzheimer's disease (AD), effective multi-targeted directed ligands (MTDLs) are urgently needed for its treatment as single-target drugs currently encounter therapeutic challenges. Two series of new 4-aminoquinoline derivatives containing an amine or hydroxamic acid terminal were designed, synthesized and evaluated for their cholinesterase inhibition, antioxidant and metal-ion chelation properties. Among them, hydroxamic acid-containing compounds 7r and 7f exhibited the best inhibitor activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), respectively, with the corresponding IC values of 0.41 and 1.06 μM, which were superior to those of rivastigmine (IC = 5.26, 2.02 μM, respectively). Moreover, compounds 7r and 7f presented excellent ABTS radical scavenging efficiency and selective metal-ion chelation ability such as Cu and Fe. Both molecular docking and enzyme kinetic analysis revealed that compound 7r was a mixed-type inhibitor of AChE. Additionally, the ADME prediction indicated that compounds 7r and 7f have suitable pharmacokinetic and drug-like properties. Furthermore, they demonstrated good safety and blood-brain barrier permeability in cytotoxicity assays and in vivo experiments, respectively. These findings strongly suggest that the 4-aminoquinoline derivatives containing a hydroxamic acid terminal have great potential as promising MTDLs for the treatment of AD, opening new avenues for future therapeutic strategies.

In the interdisciplinary domains of medicine and chemistry, addressing the issue of residual drugs (toxicants) that fail to fully exert therapeutic effects while potentially inducing toxic side effects has become increasingly critical. Researchers are actively seeking innovative solutions to this multifaceted challenge. Conventional small-molecule antagonists, commonly used in clinical settings, typically depend on "drug-receptor interactions" yet pose substantial developmental challenges. Recent advancements in the investigation of macrocyclic host compounds present a promising alternative. By leveraging the principles of host-guest chemistry, these macrocyclic hosts form stable inclusion complexes with residual drugs (toxicants), thereby decreasing their free concentration in the bloodstream and effectively mitigating associated toxic side effects. Consequently, macrocyclic host compounds represent a novel class of supramolecular antagonists (SAs). This article reviews recent progress in the application of macrocyclic host molecules-such as cyclodextrin, calix[n]arene, pillar[n]arene, and cucurbit[n]uril-as SA and examines current issues and future development prospects within the field.

Committed to our growing effort addressed toward the development of potent anti-breast cancer candidates, new 4-hydrazinylpyrimidine-5-carbonitriles featuring a morpholinyl or piperidinyl moiety at the position-2 and derivatized with various functionalities at the hydrazinyl group were designed through structure optimization, and their antiproliferative potency against two human breast cancer (BC) cell lines, relative to the reference drug 5-FU, was evaluated. Compounds showing remarkable cytotoxic activity versus the hormone dependent MCF-7 cell line (IC = 1.62 ± 0.06 µM- 9.88 ± 0.38 µM) and the non-hormone dependent MDA-MB-231 cell line (IC = 3.26 ± 0.14 µM-12.93 ± 0.55 µM) were further tested by multiple assays for clarification of their potential activity. Promising derivatives revealing low damage to healthy cells were subject to enzymatic inhibitory assessment against ARO and EGFR and their activities compared to letrozole and erlotinib respectively. Compounds 3c, 6a as well as compounds 4c, 4d proved to be good inhibitors of the ARO and EGFR enzymes respectively. Active compounds were also evaluated for their underlying mode of action by further investigation for CDK, Hsp90, PI3K inhibition and compared to normal MCF-10A cells and assessed for their enhancement of the caspase 9 levels. Additionally, cell cycle analysis and apoptotic induction were performed. They demonstrated remarkable activities in the previous assays and emanated as leads as anti-breast cancer candidates. Eventually, molecular docking analysis revealed that hit compounds 3c, 4c, 4d, and 6a could bind favorably to the proposed in silico models of various protein-ligand interactions. Therefore, our promising top candidates, by demonstrating appreciable anti-breast cancer activities, present valuable prospects for optimization, potency enhancement and future application.

Due to the high incidence of diabetes and its associated complications, diabetes is widely recognized as a serious global health problem. In diabetes treatment strategies, targeting α-glucosidase, a key carbohydratehydrolyzing enzyme, has emerged as a highly regarded approach. To develop novel α-glucosidase inhibitors, we successfully synthesized a series of apigenin analogs, collectively referred to as H1-H27 compounds and examined their inhibitory effects on α-glucosidase activity. H7 showed a remarkable inhibitory effect, surpassing that of the standard drug acarbose. Further analysis revealed that H7, H10, and H24 act as non-competitive inhibitors of α- glucosidase. In vivo experiments using a type 2 diabetes mouse model demonstrated the diverse therapeutic potential of H7; it effectively lowered blood sugar levels, improved glucose tolerance, and corrected lipid metabolism. In addition, H7 showed hepatoprotective effects, highlighting its ability to improve liver function. H7 also positively influenced the gut microbiota composition in diabetic mice, increasing diversity and richness. These results highlight the promising therapeutic effects of apigenin analogs, such as H7, for treating type 2 diabetes and show how they could provide numerous benefits, including effective inhibition of α-glucosidase, improved glucose control, correction of lipid metabolism, hepatoprotection, and modulation of the intestinal microbiota.

WRN helicase is a crucial target of synthetic death in cancer and has a unique advantage in the treatment of microsatellite unstable cancers. Our previous studies have found that quinazoline derivatives showed the WRN-dependent antiproliferative activity. In this study, a series of new quinazoline derivatives were designed and synthesized by optimizing the structure, and evaluating the targeting and sensitivity to WRN helicase. Cell growth inhibition experiments on WRN overexpressing PC3 cells (PC3-WRN) showed that the antiproliferative activity of some compounds was significantly dependent on WRN helicase. Moreover, the antitumor activity of 9in vivo was significantly decreased in the nude mouse model constructed with WRN knockdown PC3 cells (PC3-shWRN) compare (P < 0.01) to the control group. The molecular docking and CETSA results showed that 9 directly binds to WRN protein. Mechanism studies have confirmed that 9 targeted WRN, and may affect the binding between WRN and other key regulators, to destroy the repair function and regulate genomic stability. In addition, 9 also has suitable pharmacokinetic parameters and low toxicity in vivo. This result indicates that the quinazoline derivative 9 could be a novel WRN function inhibitor for the treatment of prostate cancer.

Under hypoxic conditions in tumor cells, HIF-1α is unable to bind to VHL E3 ligase due to the blocked hydroxylation reaction, resulting in impaired degradation and intracellular accumulation. Mounting evidences show a close association between HIF-1α overexpression and drug resistance, treatment failure, and increased mortality. To address HIF-1α overexpression, we innovatively introduced an E3 ligase ligand to the HIF-1α inhibitor IDF-11774 using the PROTACs strategy, aiming to reactivate the degradative pathway impeded under hypoxia, and thereby achieve the degradation of HIF-1α protein under hypoxia. Western blotting analyses demonstrated that most of our designed PROTACs effectively degraded HIF-1α. Among these, compounds C3 and V2 exhibited excellent anti-proliferation activity on MDA-MB-231 cells with IC values of 48.98 μM and 7.54 μM, respectively. Both compounds induced protein degradation in a concentration-dependent manner, achieving degradation rates up to 80 %. Additionally, this degradation was inhibited by the proteasome inhibitor MG132. As a part of the ongoing effort to develop HIF-1 inhibitors, targeting the degradation of HIF-1α may offer an effective treatment strategy against solid tumors.

We designed and synthesized new quinazolinone-tethered phenyl thiourea/thiadiazole derivatives 4-26. Based on their structural characteristics, these compounds were proposed to have a multi-target mode of action for their anticancer activities. Using the MTT assay method, antiproliferative effects were assessed against three human cancer cell lines (HEPG-2, MCF-7, and HCT-116). In vitro assessment for enzymatic inhibitory activity of the most active compounds 4, 9 and 20 was done for EGFR, VEGFR-2 and COX-2 as potential targets. The screened compounds showed low micromolar IC inhibitory effects against the three targets. Compound 9 demonstrated similar EGFR/VEGFR-2 inhibitory effect to the control drugs and potential inhibitory activity for COX-2 enzyme. In MCF-7 cells, the most active analog 9 caused 41.02% total apoptosis, and arrested the cell cycle at the G2/M phase. Taken as a whole, the findings of this study provide significant new understandings into the relationship between COX inhibition and cancer therapy. Furthermore, the outcomes showcased the encouraging efficacy of these compounds with a multi-target mechanism, making them excellent choices for additional research and development into possible anticancer drug.

A non-platinum-metal decanuclear complex [NiL(CHCOO) (CHOH)]·8(CHOH) (Ni complex) has been developed with a tri-dentate 2,3-dihydroxybenzaldehyde-2-aminophenol Schiff base ligand (HL). Single crystal X-ray analysis reveals that the Ni complex displays a sandwich loaf-shaped decanuclear structure and its anticancer activity was evaluated. The cell cytotoxicity results indicating that the Ni complex is most effective to human breast cancer cells MDA-MB-231 and its mechanism were further investigated. Flow cytometry analysis showed that the Ni complex triggered cell cycle arrest and induced apoptosis of MDA-MB-231 cells. Western blot analysis of the changes of intracellular protein expression showed that Ni triggers MDA-MB-231 apoptosis through mitochondrial mediated apoptosis signaling pathways. In vivo experiments showed that the Ni complex significantly suppressed breast tumor growth with low toxicity against major organs in a nude mice model. The good treatment effect, low toxicity and pharmacological mechanisms of the decanuclear Ni complex may provide a clue for the research and development of non-platinum multinuclear based chemotherapeutic drugs.

Flaviviruses are vector-borne RNA viruses that seriously threaten global public health due to their high transmission index in humans, mainly in endemic areas. They spread infectious diseases that affect approximately 400 million people globally, primarily in developing countries struggling with persistent epidemic diseases. Viral infections manifest as hemorrhagic fever, encephalitis, congenital abnormalities, and fatalities. Despite nearly two decades of drug discovery campaigns, researchers have not identified promising lead compounds for clinical trials to treat or prevent flavivirus infections. Although scientists have made substantial progress through drug discovery approaches and vaccine development, resolving this complex issue might need some time. New therapeutic agents that can safely and effectively target key components of flaviviruses need to be identified. NS2B-NS3pro is an extensively studied pharmacological target among viral proteases. It plays a key role in the viral replication cycle by cleaving the polyprotein of flaviviruses and triggering the formation of structural and non-structural proteins. In this review, studies published from 2014 to 2023 were examined, and the specificity profile of compounds targeting NS2B-NS3 pro proteases for treating flavivirus infections was focused on. Additionally, the latest advancements in clinical trials were discussed. This article might provide information on the prospects of this promising pharmacological target.

Antibiotic resistance has emerged as a pressing global health issue. Polymyxin E, commonly regarded as a clinically important antibiotic, faces limitations due to its dose-dependent toxicity. A crucial strategy to combat this is the development of an antibiotic adjuvant to enhance efficacy while reducing dosage. Screening from our extensive in-house compound library, KJ1071 emerged as a promising adjuvant candidate for polymyxin E. Subsequent structure-activity relationship studies led to the discovery of compound A35, which demonstrated superior synergistic activity. However, its limited aqueous solubility posed challenges for biological experiments. To address this, we carried out a structural derivatization aimed at enhancing its solubility. The amino acid derivative A59 notably improved aqueous solubility to 3.237 mg/mL, a substantial 3237-fold increase compared to compound A35. Moreover, A59 amplified the efficacy of polymyxin E in eradicating a variety of Gram-negative bacteria, including certain clinical strains that are resistant to polymyxin E. The mechanism studies indicated that A59 might target the bacterial membrane. These findings suggest that the discovery of this innovative scaffold could provide critical insights for new adjuvant therapies.