Publications by authors named "Hyung Ryong Moon"

2-Mercaptomethylbenzo[]imidazole (2-MMBI) derivatives were designed and synthesized as tyrosinase (TYR) chelators using 2-mercaptomethylimidazole scaffolds. Seven of the ten 2-MMBI derivatives exhibited stronger inhibition of mushroom TYR activity than kojic acid. Their ability to chelate copper ions was demonstrated through experiments using the copper chelator pyrocatechol violet and assays measuring TYR activity in the presence or absence of exogenous CuSO.

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Article Synopsis
  • * Resorcinol-containing compounds showed significantly better mushroom tyrosinase inhibition compared to kojic acid, with one compound achieving a remarkable IC value of 0.51 μM.
  • * These compounds not only inhibited tyrosinase activity and melanin production effectively in cell tests but also demonstrated strong depigmentation in zebrafish larvae without causing toxicity, indicating their safety for use on skin.
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Based on the hypothesis that the 2-mercaptoacetamide moiety chelates the copper ions of tyrosinase, 2-mercapto--arylacetamide (2-MAA) analogs were designed and synthesized as potential tyrosinase inhibitors. Four 2-MAA analogs showed low IC values ranging from 0.95 to 2.

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Tyrosinase is a metalloenzyme that contains copper(II) ions. We designed and synthesized eight known low-molecular-weight 2-mercaptobenzoxazole (2-MBO) analogs as tyrosinase inhibitors. Our focus was on the mercapto functional group, which interacts with copper ions.

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Article Synopsis
  • Compounds with sulfhydryl groups and azole structures, like 2-thiobenzothiazole (2-TBT), show strong potential to inhibit the enzyme tyrosinase, which is linked to melanin production.
  • Eight out of ten synthesized 2-TBT derivatives effectively inhibited tyrosinase's activity, significantly impacting melanogenesis in specific cell lines and outperforming traditional inhibitors like kojic acid in experimental models.
  • The mechanisms of action suggest that these derivatives work by binding to the active site of tyrosinase, potentially offering a new approach for treating hyperpigmentation disorders.
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Article Synopsis
  • Researchers developed benzylidene-3-methyl-2-thioxothiazolidin-4-one (BMTTZD) analogs to target and inhibit tyrosinase, an enzyme involved in melanin production.
  • Some of these analogs showed significantly stronger inhibition than the common treatment, kojic acid, especially in the presence of l-tyrosine and l-dopa.
  • The analogs also demonstrated strong antioxidant effects and reduced melanin production in cell experiments, indicating their potential use in treating hyperpigmentation disorders.
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Recently, 10 2-mercaptobenzo[d]imidazole (2-MBI) compounds (1-10) were synthesized. Although all 2-MBI compounds are tyrosinase inhibitors that inhibit mushroom tyrosinase at extremely low concentrations (IC values: 20-740 nM) and effectively inhibit the browning of apples, to our knowledge, no studies have determined whether 2-MBI compounds inhibit mammalian tyrosinase. Mammalian tyrosinase is different from mushroom tyrosinase in its distribution within the cell and has structural characteristics that are different from mushroom tyrosinase in amino acid sequence and in the presence of a quaternary structure.

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As the β-phenyl-α,β-unsaturated carbonyl (PUSC) structure was previously identified to play a key role in tyrosinase inhibition, 14 analogs with a PUSC structure built on a thiazol-4(5H)-one scaffold were synthesized using Knoevenagel condensation to serve as potential tyrosinase inhibitors. Through mushroom tyrosinase inhibition experiments, two analogs 9 and 11 were identified as potent tyrosinase inhibitors, with 11 exhibiting an IC value of 0.4 ± 0.

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This study investigated the potential of a newly synthesized histone deacetylase (HDAC) inhibitor, MHY446, in inducing cell death in HCT116 colorectal cancer cells and compared its activity with that of suberoylanilide hydroxamic acid (SAHA), a well-known HDAC inhibitor. The results showed that MHY446 increased the acetylation of histones H3 and H4 and decreased the expression and activity of HDAC proteins in HCT116 cells. Additionally, MHY446 was confirmed to bind more strongly to HDAC1 than HDAC2 and inhibit its activity.

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Chronic kidney disease (CKD) is a kidney structure and function abnormality. CKD development and progression are strongly influenced by oxidative stress and inflammatory responses, which can lead to tubulointerstitial fibrosis. Unfortunately, there are no effective or specific treatments for CKD.

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Ten 2-mercaptobenzimidazole (2-MBI) analogs were synthesized as potential tyrosinase inhibitors because mercapto-containing compounds can bind to copper ions at the active site of tyrosinase to inhibit enzyme activity. Nine 2-MBI analogs showed sub-micromolar IC values for mushroom tyrosinase monophenolase activity; analog was 280-fold more potent than kojic acid, and in diphenolase activity, was 970-fold more potent than kojic acid. The inhibition mode of the 2-MBI analogs was investigated using kinetic studies supported by docking simulations.

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Mushroom tyrosinase is a tetramer, whereas mammalian tyrosinase is a monomeric glycoprotein. In addition, the amino acid sequence of mushroom tyrosinases differs from that of mammalian tyrosinases. MHY2081 exhibits potent inhibitory activity against both mushroom and mammalian tyrosinases.

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Colon-targeted oral drug delivery systems comprising nanoparticles and microparticles have emerged as promising tools for the treatment of ulcerative colitis (UC) because they minimize side effects and maximize the local drug concentration. Dexamethasone sodium phosphate (DSP) is a potent anti-inflammatory glucocorticoid used for the treatment of UC. However, it remains a rather short-term treatment option owing to its side effects.

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Two synthetic compounds, MHY1383, azo-resveratrol and MHY1387, 5-[4-hydroxy-3,5-methoxybenzy]-2-thioxodihydropyrimidine-4,6[1H,5H]-dione have been reported to have an anti-biofilm effect on at very low concentrations (1-10 pM). Here, we investigated the anti-biofilm effects of these compounds in various bacteria. We found that MHY1383 significantly inhibited , , and biofilm formation at 1 pM, 1 nM, and 10 nM, respectively.

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Activating NRF2-driven transcription with non-electrophilic small molecules represents an attractive strategy to therapeutically target disease states associated with oxidative stress and inflammation. In this study, we describe a campaign to optimize the potency and efficacy of a previously identified bis-sulfone based non-electrophilic ARE activator 2. This work identifies the efficacious analog 17, a compound with a non-cytotoxic profile in IMR32 cells, as well as ARE activators 18 and 22, analogs with improved cellular potency.

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()-5-Benzylidene-2-phenylthiazol-4(5)-one (()-BPT) derivatives were designed by combining the structural characteristics of two tyrosinase inhibitors. The double-bond geometry of trisubstituted alkenes, ()-BPTs -, was determined based on the coupling constant of H-coupled C NMR spectra. Three ()-BPT derivatives (-) showed stronger tyrosinase inhibitory activities than kojic acid; in particular, was to be 189-fold more potent than kojic acid.

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Flavone derivatives were designed and synthesized based on the hypothesis that flavones containing the β-phenyl-α,β-unsaturated carbonyl (PUSC) scaffold have potential anti-tyrosinase activity. Flavones 1a and 1e inhibited mushroom tyrosinase more potently than kojic acid, and 1e inhibited monophenolase and diphenolase 61- and 28-fold more than kojic acid, respectively. Kinetic studies on mushroom tyrosinase indicated that 1a and 1e competitively inhibit monophenolase and diphenolase, and docking results supported these results.

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The peroxisome proliferator-activated receptor (PPAR) nuclear receptor has been an interesting target for the treatment of chronic diseases. Although the efficacy of PPAR pan agonists in several metabolic diseases has been well studied, the effect of PPAR pan agonists on kidney fibrosis development has not been demonstrated. To evaluate the effect of the PPAR pan agonist MHY2013, a folic acid (FA)-induced in vivo kidney fibrosis model was used.

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In this study, ()-2-(benzylamino)-5-benzylidenethiazol-4(5)-one (BABT) derivatives were designed as tyrosinase inhibitors based on the structure of MHY2081, using a simplified approach. Of the 14 BABT derivatives synthesized, two derivatives (()-2-(benzylamino)-5-(3-hydroxy-4-methoxybenzylidene)thiazol-4(5)-one [] and ()-2-(benzylamino)-5-(2,4-dihydroxybenzylidene)thiazol-4(5)-one []) showed more potent mushroom tyrosinase inhibitory activities than kojic acid, regardless of the substrate used; in particular, compound was 106-fold more potent than kojic acid when l-tyrosine was used as the substrate. Analysis of Lineweaver-Burk plots for and indicated that they were competitive inhibitors, which was confirmed via in silico docking.

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5-Fluorouracil (5-FU) is a widely used chemotherapeutic agent for colorectal cancer (CRC) owing to its potent anticancer effects. However, severe systemic side effects and poor drug accumulation in the CRC tissues limit its efficacy. This study aimed to develop 5-FU crystal-incorporated, pH-responsive, and release-modulating poly(d,l-lactide-co-glycolide)/Eudragit FS hybrid microparticles (5FU-EPMPs) for the local CRC-targeted chemotherapy.

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Although various local anti-inflammatory therapies for ulcerative colitis have been developed, rapid drug elimination from inflamed colitis tissue and off-target side effects reduce their therapeutic efficacy. In this study, we synthesized curcumin (Cur)-loaded hyaluronic acid (HA)-conjugated nanoparticles (Cur-HA-PLGA-NPs) that target inflamed colitis tissue via HA-CD44 interaction with resident colonic epithelial cells and subsequently target activated macrophages for ulcerative colitis therapy. The synthesized spherical Cur-HA-PLGA-NPs showed physicochemical properties similar to those of non-HA-conjugated Cur-PLGA-NPs.

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Many compounds containing the β-phenyl-α,β-unsaturated carbonyl (PUSC) scaffold, including cinnamamide derivatives, have been shown to inhibit tyrosinase potently in vitro and in vivo. Structural changes to cinnamamide derivatives were produced by adding a dithionate functional group to provide eight ()-5-(substituted benzylidene)-3-cyclohexyl-2-thioxothiazolidin-4-one analogs with high log values for skin. These analogs were synthesized using a two-step reaction, and their stereochemistry was confirmed using the values of C4 measured in proton-coupled C mode.

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Background: The protein kinase A (PKA)/cAMP response element-binding protein (CREB) has been suggested to be related to the inhibition of the proliferation of non-small cell lung cancer (NSCLC) cells. This study aimed to investigate the efficacy of a novel diarylcyclohexanone derivative, MHY4571, in regulating the PKA-CREB pathway and to study its anti-tumor role in squamous NSCLC.

Methods: We designed MHY4571 as a novel PKA inhibitor with acceptable in silico ADME properties and tested it in vitro in lung cancer cell lines and in vivo in xenograft and orthotopic mouse models of squamous cell lung carcinoma.

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Sixteen compounds bearing a benzothiazole moiety were synthesized as potential tyrosinase inhibitors and evaluated for mushroom tyrosinase inhibitory activity. The compound 4-(5-(trifluoromethyl)benzo[]thiazol-2-yl)benzene-1,3-diol (compound ) exhibited the highest tyrosinase activity inhibition, with an IC value of 0.2 ± 0.

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