Chem Pharm Bull [journal]
- The synthesis and evaluation of arctigenin amino acid ester derivatives. [JOURNAL ARTICLE]
- Chem Pharm Bull (Tokyo) 2016 Jul 6.
The use of arctigenin (ARG), a traditional medicine with many pharmacological activities, has been restricted due to its poor solubility in water. Five amino acid derivatives of ARG have been synthesized using glycine, o-alanine, valine, leucine, and isoleucine, which have BOC as a protective group. In this study, we examined the effects of removing these protective groups. The results showed that the amino acid derivatives have better solubility and nitrite-clearing ability than ARG. Among the compounds tested, the amino acid derivatives without protective group were the best. Based on these results, ARG and its two amino acid derivatives without protective group (ARG8 and ARG10) were selected to evaluate their anti-tumor activity in vivo at a dosage of 40 mg/kg. The results indicated that ARG8 and ARG10 both exhibit more anti-tumor activity than ARG in H22 tumor-bearing mice. The tumor inhibition rates of ARG8 and ARG10 were 69.27% and 43.58%, which was much higher than ARG. Furthermore, the mice treated with these compounds exhibited less damage to the liver, kidney and immune organs compared with the positive group. Furthermore, ARG8 and ARG10 improved the serum cytokine levels significantly compared to ARG. In brief, this study provides a method to improve the water solubility of drugs, and we also provide a reference basis for new drug development.
- Metabolomic Approach for Discrimination of Four- and Six-year-old Red Ginseng (Panax ginseng C.A. Meyer) using UPLC-QToF-MS. [JOURNAL ARTICLE]
- Chem Pharm Bull (Tokyo) 2016 Jul 5.
Panax ginseng C.A. Meyer is one of the most popular medicinal herbs in Asia and the chemical constituents are changed by processing methods such as steaming or sun drying. Metabolomic analysis was performed to distinguish age discrimination of four- and six-year-old red ginseng using ultra-performance liquid chromatography quadruple time of flight mass spectrometry (UPLC-QToF-MS) with multivariate statistical analysis. Principal component analysis (PCA) showed clear discrimination between extracts of red ginseng of different ages and suggest totally six discrimination markers (two for four-year-old and four for six-year-old red ginseng). Among these, one marker was isolated and the structure determined by NMR spectroscopic analysis was 13-cis-docosenamide (marker 6-1) from six-year-old red ginseng. This is the first report of a metabolomic study regarding the age differentiation of red ginseng using UPLC-QToF-MS and determination of the structure of the marker. These results will contribute to the quality control and standardization as well as provide a scientific basis for pharmacological research on red ginseng.
- Synthesis, characterization and antifungal evaluation of novel thiochromanone derivatives containing indole skeleton. [JOURNAL ARTICLE]
- Chem Pharm Bull (Tokyo) 2016 Jul 2.
Invasive fungal disease constitutes a growing health problem and development of novel antifungal drugs with high potency and selectivity against new fungal molecular targets are urgently needed. In order to develop potent antifungal agents, a novel series of 6-alkyl-indolo[3,2-c]-2H-thiochroman derivatives were synthesized. Microdilution broth method was used to investigate antifungal activity of these compounds. Most of them showed good antifungal activity in vitro. 4o showed the best antifungal activity, which (inhibition of Candida albicans and Cryptococcus neoformans) can be achieved at the concentration of 4 μg/mL. 4b (inhibition of Cryptococcus neoformans), 4j (inhibition of Cryptococcus neoformans), 4d (inhibition of Candida albicans) and 4h (inhibition of Candida albicans) also showed the best antifungal activity at the concentrations of 4 μg/mL. The molecular interactions between 4o and the N-myristoyltransferase of Candida albicans (PDB ID: 1IYL) were finally investigated through molecular docking. The results indicated that these thiochromanone derivatives containing indole skeleton could serve as promising leads for further optimization as novel antifungal agents.
- Synthesis of Dendrimers with a Bidentate Phosphine Core Ligand Having Carboxy Groups at the Peripheral Layer and Their Application to Aqueous Media Cross-Coupling Reactions. [Journal Article]
- Chem Pharm Bull (Tokyo) 2016; 64(7):1067-72.
We prepared a series of dendrimers with a bidentate phosphine core ligand having carboxy groups at the peripheral layer. By employing the corresponding water-soluble dendritic phosphine-palladium complex as a catalyst, the aqueous media Suzuki-Miyaura reaction and Tsuji-Trost reaction proceeded to provide the corresponding cross-coupling product.
- Sesquiterpenoids from the Rhizomes of Curcuma phaeocaulis and Their Inhibitory Effects on LPS-Induced TLR4 Activation. [Journal Article]
- Chem Pharm Bull (Tokyo) 2016; 64(7):1062-6.
Two new guaiane-type (2, 6) and one new furanogermacrane-type (11) sesquiterpenoids have been isolated along with twelve known compounds from an EtOAc-soluble extract of Curcuma phaeocaulis rhizomes. The structures of the isolated compounds were elucidated using a combination of NMR, MS, and circular dichroism (CD) spectra. The inhibitory effects of each compound on lipopolysaccharide (LPS)-induced Toll-like receptor 4 (TLR4) activation in THP-1-Blue cells were assessed, and compound 4 showed more potent inhibitory activity against LPS-stimulated TLR4 activation.
- Reaction of 2a,8b-Dihydrobenzo[b]cyclobute[d]pyran-3-ones with Dimethylsulfoxonium Methylide. [Journal Article]
- Chem Pharm Bull (Tokyo) 2016; 64(7):1056-61.
Using dimethylsulfoxonium methylide as the methylene transfer reagent, 2a,8b-dihydrobenzo[b]cyclobute[d]pyran-3-ones were converted into 2,2'-biphenol derivatives as major products and dihydrodibenzofurans as minor products. The reaction mechanism was extrapolated from a deuteration experiment with CD2=S(O)(CD3)2.
- Molecular Orbital Study of the Formation of Intramolecular Hydrogen Bonding of a Ligand Molecule in a Protein Aromatic Hydrophobic Pocket. [Journal Article]
- Chem Pharm Bull (Tokyo) 2016; 64(7):1031-5.
The natural product argadin is a cyclopentapeptide chitinase inhibitor that binds to chitinase B (ChiB) from the pathogenic bacteria Serratia marcescens. N(ω)-Acetyl-L-arginine and L-aminoadipic acid of argadin form intramolecular ionic hydrogen bonds in the aromatic hydrophobic pocket of ChiB. We performed ab initio molecular orbital and density functional theory calculations to elucidate the role of this intramolecular hydrogen bonding on intermolecular interactions between argadin and ChiB. We found that argadin accrues large stabilization energies from the van der Waals dispersion interactions, such as CH-π, π-π, and π-lone pair interactions, in the aromatic hydrophobic pocket of ChiB, although intramolecular hydrogen bonding within argadin might result in loss of entropy. The intramolecular ionic hydrogen bonding formation canceled local molecular charges and provided good van der Waals interactions with surrounding aromatic residues.
- Iriomoteolides-10a and 12a, Cytotoxic Macrolides from Marine Dinoflagellate Amphidinium Species. [Journal Article]
- Chem Pharm Bull (Tokyo) 2016; 64(7):1019-23.
Two new macrolides, iriomoteolides-10a (1) and -12a (2), have been isolated from a marine dinoflagellate Amphidinium sp. (KCA09053 strain), and their structures were elucidated on the basis of a detailed two dimensional (2D)-NMR analysis. Compound 1 is a novel 21-membered Amphidinium macrolide, which contains one tetrahydrofuran ring, two ketone carbonyls, two hydroxyl groups, and six one-carbon branches. Compound 2 is a new 12-membered macrolide related to amphidinolide Q. Compound 1 exhibited cytotoxic activity against human cervix adenocarcinoma HeLa and murine hepatocellular carcinoma MH134 cells.
- O-Glycosylation of 4-(Substituted benzyl)-1,2-dihydro-3H-pyrazol-3-one Derivatives with 2,3,4,6-Tetra-O-acyl-α-D-glucopyranosyl Bromide via N1-Acetylation of the Pyrazole Ring. [Journal Article]
- Chem Pharm Bull (Tokyo) 2016; 64(7):1009-18.
A practical preparation of 4-(substituted benzyl)-3-(2,3,4,6-tetra-O-acyl-β-D-glucopyranosyloxy)-1H-pyrazole derivative 2 is described. O-Glycosylation of 4-(substituted benzyl)-1,2-dihydro-3H-pyrazol-3-one derivative 3 was facilitated by introduction of electron-withdrawing substituents, such as an acetyl group, at the N1-position of the pyrazole ring. 1-Acetyl-4-(substituted benzyl)-1,2-dihydro-3H-pyrazol-3-one 10 reacted with 2,3,4,6-tetra-O-acyl-α-D-glucopyranosyl bromide 5 in the presence of potassium carbonate in acetonitrile to provide the 1-acetyl-4-(substituted benzyl)-3-(2,3,4,6-tetra-O-acyl-β-D-glucopyranosyloxy)-1H-pyrazole derivative 11 in high yield. When 2,3,4,6-tetra-O-pivaloyl-α-D-glucopyranosyl bromide (5b) was used as a glycosyl donor, the resulting O-glycosylated product 11 was N1-deacetylated in the presence of potassium bicarbonate in methanol without unfavorable deprotection of the glycosyl moiety to provide 2 in excellent yield. The synthetic intermediate 2b of Remogliflozin etabonate (1b) was synthesized using this strategy.
- Functional Interrogation of the N-Terminal Lid of MDMX in p53 Binding via Native Chemical Ligation. [Journal Article]
- Chem Pharm Bull (Tokyo) 2016; 64(7):1004-8.
The homologous proteins MDM2 and MDMX negatively regulate the tumor suppressor protein p53 by antagonizing p53 transactivation activity and targeting p53 for degradation. MDM2 and MDMX bind to p53 via N-terminal p53-binding domains to control the level of p53. The N-terminal regions of MDM2 and MDMX are modified in vivo under stressed conditions, suggesting that modifications to MDM2/MDMX also may affect the p53-MDM2/MDMX interaction. Ample evidence suggests that the MDM2 lid (residues 1-24) is partially structured and significantly reduces its binding affinity with p53 several fold. Since MDM2 and MDMX possess very similar p53-binding domains but different lids, however, the function of the N-terminal lid of MDMX still remains poorly understood. Using a native chemical ligation technique, the p53-binding domain of MDMX, (1-108)MDMX, and its N-terminal lid (residues 1-23) truncated analogue (24-108)MDMX were chemically synthesized. We comparatively characterized their structures by circular dichroism (CD) spectra, and measured their binding affinities with a panel of p53-derived peptide ligands by fluorescence polarization and surface plasmon resonance assays. Our results indicate that, as opposed to the lid of MDM2, the lid of MDMX has little effect on p53-binding, adopts no structural conformation, and has rare auto-inhibitory function. Different lid modifications of MDM2 and MDMX are functionally different with respect to p53 binding, which should be considered when designing dual specific inhibitors of MDM2 and MDMX.