Chem Pharm Bull [journal]
- Three new polyphenolic acids from the leaves of Eucalyptus citriodora with antivirus activity. [JOURNAL ARTICLE]
- Chem Pharm Bull (Tokyo) 2016 Aug 13.
Six polyphenolic acids (1-6), including the three new compounds citriodolic acids A, B and C (1-3), were isolated from the leaves of Eucalyptus citriodora. Their structures were elucidated by spectroscopic methods including one dimensional (1D)- and 2D-NMR, high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), and circular dichroism (CD). The potential antivirus activity against respiratory syncytial virus (RSV) of all the isolated compounds was evaluated.
- Oxidative stress is involved in the renal dysfunction induced by sinoaortic denervation in rats. [JOURNAL ARTICLE]
- Chem Pharm Bull (Tokyo) 2016 Aug 4.
The hypothesis that oxidative stress contributes to renal dysfunction in sinoaortically denervated (SAD) rats was investigated. Rats were sinoaortically denervated and received treatment with tempol (0.5 mmol/l in drinking water) for 8 weeks. Although the tempol treatment of the SAD rats had no significant effect on blood pressure or blood pressure viability, it significantly ameliorated the renal dysfunction as indicated by increases in renal blood flow (RBF) and the glomerular filtration rate (GFR) and reductions in plasma creatinine, blood urea nitrogen (BUN), the urine albumin excretion rate (UAE), and the glomerular sclerosis score (GSS). The SAD rats treated with tempol exhibited decreased plasma and renal malondialdehyde (MDA) levels and reduced renal formation of reactive oxygen species (ROS), O2(－), OONO(－)and 3-nitrotyrosine. Treatment with tempol suppressed the nuclear concentration of NF-κB and reduced the renal levels of macrophage chemoattractant protein 1 (MCP-1) and interleukin-6 (IL-6). The tempol-treated SAD rats exhibited decreased renal advanced glycation end product (AGE) levels and decreased receptor for advanced glycation end products (RAGE) protein expression. The tempol treatment of the SAD rats restored mitochondrial adenosine triphosphate (ATP) formation, DNA content, membrane integrity and the renal oxygen consumption rate. Additionally, the activities of SOD, GPx, GST, and catalase were decreased, and the activities of XO and NADPH oxidase were enhanced in the kidneys of the SAD rats. In conclusion, our work firstly provided direct evidence that oxidative stress played an important role in the renal dysfunction of SAD rats.
- Practical Synthesis of Axially Chiral Dicarboxylates via Pd-Catalyzed External-CO-Free Carbonylation. [JOURNAL ARTICLE]
- Chem Pharm Bull (Tokyo) 2016 Aug 3.
We have developed a safe and practical synthetic method for preparing axially chiral diphenyl dicarboxylates using Pd-catalyzed external-CO-free carbonylation with phenyl formate as a CO surrogate. Optimized conditions consisted of axially chiral [1,1'-binaphthalene]-2,2'-diyl ditriflate and its congeners, each easily prepared from commercially available enantiomerically pure diols, Pd(OAc)2, 1,3-bis(diphenylphosphino)propane, ethyldiisopropylamine, and no solvent. To demonstrate the potential utility of these products, this method was conducted on gram-scale and the phenyl ester products were converted to other useful compounds, and both processes were carried out without difficulty.
- Cytotoxic Oxygenated Steroids from the Soft Coral Nephthea erecta. [JOURNAL ARTICLE]
- Chem Pharm Bull (Tokyo) 2016 Aug 3.
A new 10-demethylated steroid, nephtheasteroid A (1), a new 19-oxygenated steroid, nephtheasteroid B (2) as well as five known steroids 3-7 were isolated from the organic extract of a Taiwanese soft coral Nephthea erecta. The structure was determined by means of IR, MS, and NMR techniques. Among these metabolites, 1 is rarely found in steroids possessing a 19-norergostane skeleton. In vitro cytotoxicity study using MTT assay revealed that compounds 3 and 4 exhibited cytotoxicity against K562, Molt-4, Sup-T1 and U937, with IC50 of 6.5-14.0 μM.
- Concise Synthesis of (2R,4R)-Monatin. [Journal Article]
- Chem Pharm Bull (Tokyo) 2016; 64(8):1242-7.
Monatin, 4-hydroxy-4-(3-indolylmethyl)-glutamic acid, is a naturally occurring sweet amino acid. The (2R,4R)-monatin isomer has been found to be the sweetest among its four stereoisomers. A concise and efficient synthesis of (2R,4R)-monatin was accomplished by the alkylation of (4R)-N-tert-butoxycarbonyl (tBoc)-4-tert-butyldimethylsilyoxy-D-pyroglutamic acid methyl ester with tert-butyl 3-(bromomethyl)-1H-indole-1-carboxylate to give (4R)-N-tBoc-4-tert-butyldimethylsilyloxy-4-(N-tBoc-3-indolylmethyl)-D-pyroglutamic acid methyl ester, i.e., the lactam form of (2R,4R)-monatin with protecting groups. This was followed by the hydrolysis of the lactam ring and deprotection. The 4-hydroxyl D-pyroglutamic acid derivative was demonstrated to be a suitable precursor for the efficient preparation of (2R,4R)-monatin in high optical purity because the alkylation proceeded in regioselective and stereoselective manners at C4 to form appropriate asymmetric tetra-substituted carbon center; the resulting alkylated pyroglutamic acid derivative was then easily converted into the linear form of monatin.
- Reaction of Thymidine with Hypobromous Acid in Phosphate Buffer. [Journal Article]
- Chem Pharm Bull (Tokyo) 2016; 64(8):1235-8.
When thymidine was treated with hypobromous acid (HOBr) in 100 mM phosphate buffer at pH 7.2, two major product peaks appeared in the HPLC chromatogram. The products in each peak were identified by NMR and MS as two isomers of 5-hydroxy-5,6-dihydrothymidine-6-phosphate (a novel compound) and two isomers of 5,6-dihydroxy-5,6-dihydrothymidine (thymidine glycol) with comparable yields. 5-Hydroxy-5,6-dihydrothymidine-6-phosphate was relatively stable, and decomposed with a half-life of 32 h at pH 7.2 and 37°C generating thymidine glycol. The results suggest that 5-hydroxy-5,6-dihydrothymidine-6-phosphate in addition to thymidine glycol may have importance for mutagenesis by the reaction of HOBr with thymine residues in nucleotides and DNA.
- Morinlongosides A-C, Two New Naphthalene Glycoside and a New Iridoid Glycoside from the Roots of Morinda longissima. [Journal Article]
- Chem Pharm Bull (Tokyo) 2016; 64(8):1230-4.
Two new naphthalene glycosides, morinlongosides A and B (1, 2) and a new iridoid glycoside, morinlongoside C (3), together with four known ones, geniposidic acid (4), (3R)-3-O-[β-D-xylopyranosyl-(1→6)-β-D-glucopyranosyl]-l-octen-3-ol (5), lucidin-3-O-β-primeveroside (6), and morindone-6-O-β-gentiobioside (7), were isolated from the roots of Morinda longissima Y. Z. RUAN. The structures of all isolated compounds (1-7) were elucidated on the basis of spectroscopic data (high resolution (HR)-MS, one and two dimensional (1/2D)-NMR).
- Quantitative Appearance Inspection for Film Coated Tablets. [Journal Article]
- Chem Pharm Bull (Tokyo) 2016; 64(8):1226-9.
The decision criteria for the physical appearance of pharmaceutical products are subjective and qualitative means of evaluation that are based entirely on human interpretation. In this study, we have developed a comprehensive method for the quantitative analysis of the physical appearance of film coated tablets. Three different kinds of film coated tablets with considerable differences in their physical appearances were manufactured as models, and their surface roughness, contact angle, color measurements and physicochemical properties were investigated as potential characteristics for the quantitative analysis of their physical appearance. All of these characteristics were useful for the quantitative evaluation of the physical appearances of the tablets, and could potentially be used to establish decision criteria to assess the quality of tablets. In particular, the analysis of the surface roughness and film coating properties of the tablets by terahertz spectroscopy allowed for an effective evaluation of the tablets' properties. These results indicated the possibility of inspecting the appearance of tablets during the film coating process.
- New 3,4-seco-Grayanane Diterpenoids from the Flowers of Pieris japonica. [Journal Article]
- Chem Pharm Bull (Tokyo) 2016; 64(8):1222-5.
Three new 3,4-seco-grayanane diterpenoids, neopierisoids D-F (2-4), and a new natural one, neopierisoid C (1), were isolated from the flowers of Pieris japonica. Their structures were elucidated on the basis of extensive spectroscopic analysis, including one and two dimensional (1- and 2D)-NMR, as well as high resolution-electron ionization (HR-EI)-MS.
- Photostable Solid Dispersion of Nifedipine by Porous Calcium Silicate. [Journal Article]
- Chem Pharm Bull (Tokyo) 2016; 64(8):1218-21.
Nifedipine (NIF) is a typical light-sensitive drug requiring protection from light during manufacture, storage, and handling of its dosage forms. The purpose of this study was to evaluate the utility of porous calcium silicate (PCS) for maintaining the photostability of NIF in a solid dispersion formulation. Adsorption solid dispersion (ASD) prepared using NIF and PCS as an amorphous formulation was more stable to light irradiation than a physical mixture of NIF and microcrystalline cellulose (a control physical mixture) as a crystalline formulation. In addition, PCS in physical mixtures with NIF adequately protected NIF from photodegradation, suggesting that this protective effect could be because of some screening effect by the porous structure of PCS blocking the passage of light reaching NIF in pores of PCS. These findings suggest that PCS is useful for improving the solubility and photostability of NIF in solid dispersion formulation.