Chalcone derivatives (3a—m) were prepared by condensing 4-aminoacetophenone with various substituted aromatic and hetero aromatic aldehydes according to Claisen–Schmidt condensation. These chalcones, on reaction with guanidine hydrochloride under basic alcoholic conditions gave 2,4,6-trisubstituted pyrimidines (5a—m) in quantitative yields. All the newly synthesized pyrimidines were characterized by means of IR, ¹H- and ¹³C-NMR, Electron Ionization (EI)-mass and elemental analyses and screened for anti-inflammatory and analgesic activities by in vivo. 2-Amino-4-(4-aminophenyl)-6-(2,4-dichlorophenyl)pyrimidine (5b) and 2-amino-4-(4-aminophenyl)-6-(3-bromophenyl) pyrimidine (5d) were found to be the most potent anti-inflammatory and analgesic activity compared with ibuprofen, reference standard. And also it was found that compound 5b identified as lead structure among all in both the activities. Pyrimidines which showed good anti-inflammatory activity also displayed better analgesic activity.

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A rapid and sensitive analytical method for udenafil in rat plasma was developed and validated using liquid chromatography-tandem mass spectrometry (LC-MS/MS). This chromatographic procedure was then applied to the in vivo pharmacokinetic studies in rats for determining the advantages of intranasal administration of the drug over oral administration. Using liquid–liquid extraction (LLE), udenafil and the internal standard (IS) sildenafil were extracted with dichloromethane from 100 μl of plasma samples. Chromatographic separation was performed using Pursuit XRS C₁₈ column (50 mm×2.1 mm, i.d., 3 μm, Varian Inc., CA, U.S.A.) with an isocratic mobile phase consisting of acetonitrile and 10 mM ammonium acetate (90 : 10, v/v) at a flow rate of 0.2 ml/min over a total run time of 2.5 min. Detection and quantification was performed by mass spectrometry using the multiple reaction-monitoring mode at m/z 517.4→283.1 for udenafil and m/z 475.3→100.0 for IS. Results showed that the developed method was sensitive and specific for udenafil. Linearity was obtained in the range of 0.5—1000 ng/ml. The coefficient of variation of both intra- and inter-day validation were below 11.6% and the intra- and inter-day accuracy ranged from 91.5 to 109.9%. Udenafil concentration was successfully measured from plasma after intranasal as well as after intravenous or oral administration at clinical dose (1.67 mg/kg) in rats. Moreover, the T_max values obtained from pharmacokinetic studies suggested that administration of udenafil intranasally could be more effective than by the oral route.

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Different green synthesis of alkyl esters of acyclovir (acyclovir prodrugs) is described. Hexanoic, decanoic, dodecanoic and tetradecanoic acyclovir esters were synthesized reacting acyclovir and the respective acid anhydride in dimethyl sulfoxide (DMSO), in solvents from renewable sources and without solvent (T=30°C). Yields in prodrugs after 10 min of reaction were >95% using DMSO as solvent. The purification methodology was very simple, shorter and greener than previously described. The biosolvent, N,N-dimethylamide of decanoic acid, let us to obtain >95% yield at 24 h. This oily biosolvent is not dermotoxic and the reaction crude can directly be used in topic formulations. Syntheses without solvent proceeded successfully for acyclovir esters. Indeed, dodecanoate and tetradecanoate yielding >98% conversion of reactants in 30 min. In spite of requiring mild temperature (65°C), substrate molar ratios were lowered to 1 : 1, thus conducing to a more efficient use of raw materials. The synthetic procedures were scaled up to a 300 g batch (yield 98—99% isolated ester). These esters can be used as acyclovir prodrugs in topic formulations. The esters release from an oil/water micro-emulsion and a hydrogel formulation were tested with good results.

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In order to enhance the gene delivery efficiency and decrease cytotoxicity of polyplexes, copolymers consisting of branched polyethyleneimine (PEI) 25 kDa grafted with Pluronic (F127, F68, P105) were successfully synthesized using a simple two-step procedure. The copolymers were tested for cytotoxicity and DNA condensation and complexation properties. Their polyplexes with plasmid DNA were characterized in terms of DNA size and surface charge and transfection efficiency. The complex sizes were below 300 nm, which implicated their potential for intracellular delivery. The Pluronic-g-PEI exhibited better condensation and complexation properties than PEI 25 kDa. The cytotoxicity of PEI was strongly reduced after copolymerization. The Pluronic-g-PEI showed lower cytotoxicity in three different cell lines (Hela, MCF-7, and HepG2) than PEI 25 kDa. pGL3-lus was used as a reporter gene, and the transfection efficiency was in vitro measured in HeLa cells. Compared with unmodified PEI 25 kDa Pluronic-g-PEI showed much higher transfection efficiency. These results demonstrate that polyplexes prepared using a combined strategy of surface crosslinking and grafted with Pluronic seem to provide promising properties as stable, high transfection efficiency vectors.

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Four new diterpenoides, isolophanthins A—D (1—4) together with seven known abietane diterpenoides (5—11), have been isolated from Isodon lophanthoides var. gerardianus. The new diterpenoides were elucidated by spectroscopic analysis. Some of them showed significant activities against HBsAg and HBeAg of hepatitis B virus in Hep G 2.2.15 cells, as well as the human tumor cell lines, HL-60, A-549, MOLT-4, and BEL-7402.

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Daiokanzoto (DKT, combination of rhubarb and glycyrrhiza), a Kampo medicine, is clinically effective for constipation. Sennoside A is well known to induce diarrhea. Sennoside A is a prodrug that is transformed into an active metabolite, rheinanthrone, by intestinal bacteria. In this study, we investigated the effects of glycyrrhiza on the activity of sennoside A metabolism in intestinal bacteria using mouse feces. A high-performance liquid chromatography (HPLC) method for the determination of sennoside A in incubation mixture of DKT with mouse feces was established. The retention time of sennoside A was 9.26±0.02 min with a TSKgel ODS-80TsQA column by linear gradient elution using a mobile phase containing aqueous phosphoric acid and acetonitrile and detection at 265 nm. We found that the activity of sennoside A metabolism in intestinal bacteria was significantly accelerated when glycyrrhiza, liquiritin or liquiritin apioside coexisted with sennoside A, whereas that of glycyrrhizin was not altered. This method is applicable for determination of the activity of sennoside A metabolism by anaerobic incubation of DKT with mouse feces.

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The blockade of human ether-a-go-go-related gene (hERG) potassium channels is widely regarded as the predominant cause of drug-induced QT prolongation. The correlation analysis between the inhibition of the hERG channel (hERG inhibition) and physicochemical properties was investigated by use of in-house quinolone antibiotics as model compounds. In order to establish a simple prediction model of hERG inhibition, we focused on the comprehensible physicochemical parameters such as lipophilicity (log P) and basicity (pK_a). At first, the risk associated with increasing log P and pK_a was examined by statistical analysis. It was demonstrated that the risk associated with increasing log P and pK_a by one unit, respectively, almost identically increased. Consequently, equal attention should be paid to both parameters on hERG inhibition. Next, a prediction model of hERG inhibition which was represented by log P and pK_a was investigated. As a result, we built the stepwise discriminant prediction model which took advantage of the risk judgment by zone classification. In conclusion, the impact of log P and pK_a on hERG inhibition was clarified relatively and quantitatively. The quantitative risk assessment established based on both parameters, was considered to be a practical and useful tool in avoiding hERG inhibition and in the rational drug design for drug discovery, especially in lead optimization. Moreover, we also carried out a trend analysis using a different derivative and demonstrated that both parameters were equally significant for hERG inhibition.

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The aim of this study was to establish a freeze-drying process for melatonin-loaded lecithin/chitosan nanoparticles (NPs) to preserve their chemical and physical stability for a longer time period that what is possible in an aqueous suspension. Glucose and trehalose were investigated as potential excipients during freeze-drying of NP suspensions. Lecithin/chitosan NPs were characterised by mean diameter and zeta potential, ranging between 117.4 and 328.5 nm and 6.7 and 30.2 mV, respectively, depending on the lecithin type and chitosan content in the preparation. Melatonin loadings were up to 7.1%. For all lecithin/chitosan NPs, no notable differences in the mean particle size, size distribution, zeta potential or melatonin content were observed before or immediately after the lyophilisation process or after 7 months of storage at 4°C. The residual moisture contents of lyophilisates with glucose and trehalose immediately after the lyophilisation process varied between 4.0—4.8% and 2.4—3.0%, respectively. All lecithin/chitosan NPs had a fully amorphous nature after the freeze-drying process, as indicated by modulated differential scanning calorimetry. NP lyophilisates with glucose had a low glass transition temperature (ca. 5°C), confirming that lyophilisation with glucose as a cryoprotectant was not appropriate. All lyophilisates with trehalose had a glass transition temperature above the room temperature, allowing formation of the cake without a collapse of the structure, which was capable of preserving its characteristics and appearance following 7 months of storage at 4°C.

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Several hybrid molecules of diphenylamine-2,4′-dicarboxamide with various azolidinones and related heterocyclic rings have been synthesized and explored as epidermal growth factor receptor (EGFR) kinase inhibitors. Most of them displayed promising in vitro tyrosine kinase inhibition as well as potent cellular antiproliferative activity in the EGFR over-expressing breast cancer cell line (MCF-7). Compounds 12b and 13b that exhibited the highest inhibition in the kinase assay (89, 81% inhibition at 10 μM, respectively), showed potent antiproliferative effect against MCF-7 tumor cell line (IC₅₀ 1.04, 0.91 μM respectively). Molecular docking studies revealed that these compounds can bind to ATP binding site of the EGFR kinase domain and were involved in H-bonding with Met 793, in analogy to the known EGFR tyrosine kinase inhibitors. Moreover, compounds 15a—c possessed profound antitumor activity (IC₅₀ 0.59—0.73 μM) and significant EGFR-TK inhibition, making them of particular interest. In summary, the newly synthesized compounds provide promising new lead for the future design and development of anticancer agents of potential EGFR-TK inhibitory activity.

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Direct scandium- and lanthanum-catalyzed etherifications of propargyl alcohols 1 and 6 in MeNO₂–H₂O provided propargyl ethers 3, 4 and 7 in high yields. In addition, reactions of 1 and 6 with thiols exclusively yielded the corresponding propargyl sulfides.

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From aerial parts of Dianthus japonicus, six new and seven known oleanane-type triterpene saponins were isolated. The structures of the new saponins, named dianthosaponins A—F, were elucidated by means of high resolution mass spectrometry, and extensive inspection of one- and two-dimensional NMR spectroscopic data. A new C-glycosyl flavone, a glycosidic derivative of anthranilic acid amide and a maltol glucoside were also isolated.

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In this research, synthesis, antimicrobial and antioxidant activities of a series of catecholthioethers having benzoxazole and tetrazole moieties are described. Antimicrobial activity was evaluated by minimum inhibitory concentration (MIC) assay. The synthesized compounds were tested in vitro against three Gram-positive bacteria including Staphylococcus aureus (clinical isolated), Staphylococcus aureus ATCC 25922, Enterococcus faecium (clinical isolated), and two Gram-negative bacteria including Klebsiella pneumoniae (clinical isolated) and Pseudomonas aeruginosa 27853 and the yeast Candida albicans in comparison with control drugs. Microbiological results indicated that the synthesized compounds possessed a broad spectrum of activity against the tested microorganisms at MIC values between 4—256 μg/ml. This shows compounds having tetrazole moiety were the most active against Gram-negative strains, whereas compounds having benzoxazole moiety were more active against Gram-positive ones. Also both of them showed significant antifungal activity against Candida albicans and had lower activity than the compared control drugs (Sulfamethoxazole and Fluconazole). The antioxidant activity was assessed using two methods, including, 1,1-biphenyl-2-picrylhydrazyl (DPPH) radical scavenging, and reducing power assays. Some of the catecholthioether derivatives showed antioxidant activity more than Trolox and butylated hydroxyanisole (BHA) as reference antioxidants.

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A new series of novel (2S)-2-({2-[1,4-dihydro-3,5-bis(methoxycarbonyl)-2,6-dimethyl-4-(2-nitrophenyl)pyridin-1-yl]-2-oxoethyl}amino)-3-(4-hydroxyphenyl) propanoic acid (3a) and its analogues 3b—j has been synthesized. These compounds were evaluated for their in vitro antioxidant activity, anti-inflammatory activity and antiulcer activity. Compounds 3b and f exhibited significant antioxidant action comparable with that of standard. Efficacy against inflammation and ulceration was also found to be significant. The chemical structures of these compounds were confirmed on the basis of spectral data.

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Two new pimarane-type diterpenes, eutypellones A (1) and B (2), were isolated from the endophytic fungus Eutypella sp. BCC 13199. Cytotoxic activities of the pimaranes 1—5, isolated from this fungus, were evaluated.

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A new 3-hydroxydihydrobenzofuran glucoside, gnaphaliol 9-O-β-D-glucopyranoside (2), was isolated from the aerial parts of Gnaphalium polycaulon together with 1-{(2R^*,3S^*)-3-(β-D-glucopyranosyloxy)-2,3-dihydro-2-[1-(hydroxyl methyl)vinyl]-1-benzofuran-5-yl}-ethanone or gnaphaliol 3-O-β-D-glucopyranoside (1), (Z)-3-hexenyl O-β-D-glucopyranoside (3) and adenosine (4). The absolute configurations at C-2 and C-3 positions of compound 1 were determined to be 2R and 3R. The structures of these compounds were elucidated on the basis of their physical and spectroscopic data.

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Alkaline hydrolysis of the crude resin glycoside fraction of the leaves, stems, and roots of Calystegia soldanella ROEM. et SCHULT. (Convolvulaceae) gave four new glycosidic acids, named calysolic acids A, B, C, and D, along with one known glycosidic acid, soldanellic acid B, and three organic acids, 2S-methylbutyric, tiglic, and 2S,3S-nilic acids. The structures of the new glycosidic acids were characterized on the basis of spectroscopic data and chemical evidence.

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Cycloaddition reaction between toluamides and benzonitriles was applied to prepare the 3-arylisoquinolines, and their chemical transformation to the dienes 4 was performed. The ring-closing metathesis (RCM) reaction afforded the desired heterocyclic compounds, benzo[3,4]azepino[1,2-b]isoquinolinones 5 in good yield.

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Flavusides A (1) and B (2), two new antibacterial cerebroside derivatives, and the previously described phomaligol A (3), kojic acid (4), methyl kojic acid (5), and dimethyl kojic acid (6) have been isolated from the extract of a marine isolate of the fungus Aspergillus flavus. The structure and absolute stereochemistry of two cerebrosides were assigned on the basis of NMR and Tandem FAB-MS/MS experiments. Compounds 1, 2, and 3 exhibited a mild antibacterial activity against Staphylococcus aureus, methicillin-resistant S. aureus, and multidrug-resistant S. aureus. The minimum inhibitory concentration (MIC) values for each strain are as follows: compounds 1 and 2 showed 15.6 μg/ml for S. aureus and 31.2 μg/ml for methicillin-resistant S. aureus and multidrug-resistant S. aureus, and compound 3 exhibited 31.2 μg/ml for S. aureus and methicillin-resistant S. aureus and 62.5 μg/ml for multidrug-resistant S. aureus.

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A new trimethoxycinnamoyl-2-pyrrolinone alkaloid, langkamide (1), along with the known compounds piplartine (2) and 3,4,5-trimethoxycinnamic acid (3) were isolated from the roots and stems of the shrub Piper sarmentosum ROXB. The structures were established by spectroscopic analyses and comparison of their spectral data with values reported in the literature. The compounds were tested for their ability to modulate hypoxia inducible factor-2 (HIF-2) transcription activity and all three showed HIF-2 inhibitory activity with EC₅₀ values of 14.0, 4.8, and 60.6 μM, respectively, for compounds 1, 2, and 3.

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Endophytic fungi were used not only for their producing bioactive products but also for their ability to transform natural compounds. An endophytic fungus, isolated from medicinal plant Huperzia serrata, was identified as Umbelopsis isabellina based on the internal transcribed spacer of ribosomal DNA (rDNA-ITS) region. It was used to transform ursolic acid (1), a pentacyclic triterpene. Incubation of ursolic acid with U. isabellina afforded three products, 3β-hydroxy-urs-11-en-28,13-lactone (2), 3β,7β-dihydroxy-urs-11-en-28,13-lactone (3), 1β,3β-dihydroxy-urs-11-en-28,13-lactone (4). Although product 2 was a known compound, it was first obtained by microbial transformation. Products 3 and 4 were new compounds. The structural elucidation of the three compounds was achieved mainly by the 1D- and 2D-NMR, MS, IR data. The endophytic fungus U. isabellina can hydroxyate the C12–C13 double bond at position 13 of ursolic acid 1 and form a five-member lactone effectively. In the meantime, this fungus can also introduce the hydroxyl group at C-1 or C-7 of ursolic acid 1.

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Chromatographic separation of black tea polyphenols is too difficult to supply sufficient quantities of pure compounds for biological experiments. Thus, facile methods to prepare black tea constituents were desired. Treatment of epigallocatechin gallate with copper(II) chloride efficiently afforded an unstable quinone dimer, dehydrotheasinensin A, and subsequent treatment with ascorbic acid stereoselectively yielded theasinensin A. The latter is a dimer with an R-biphenyl bond, one of the major polyphenols found in black tea. The method is simpler and more effective than enzymatic preparation.

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Nine new derivatives (6—14) of the eremophilane sesquiterpene 07H239-A (5) were designed and semisynthesized with two types of R-groups by amidation. Most of them were active against five human tumor cell lines, and compounds 6—10 were more potent than the natural product 5. In particular, compounds 6 and 9 exhibited the strongest cytotoxic activity against MDA-MB-435 with IC₅₀ values of 0.91 and 0.96 μM, respectively. Preliminary structure–activity relationships (SARs) analysis indicated that the 14-carboxyl in 5 was an ideal target for chemical modification, and the side chain of 5 might play a necessary role in facilitating their cytotoxic potencies.

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We describe here a Tf₂NH-catalyzed formal (3+3) cycloaddition of silyl enol ethers with acrylates as a new domino reaction. In the domino sequence, the catalyst activates Michael addition, deprotonation of the resulting silyloxonium cation and intramolecular Claisen condensation. It was found that reaction modes significantly depend on the reaction temperature. We also examined the mechanistic detail of the reaction by ¹H-NMR experiment.

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Two new phenylallylflavanones, (2R,3R)-6-[1-(4′-hydroxy-3′-methoxyphenyl)prop-2-en-1-yl]pinobanksin (1) and (2R,3R)-6-[1-(4′-hydroxy-3′-methoxyphenyl)prop-2-en-1-yl]pinobanksin 3-acetate (2) were isolated from a methanolic extract of Mexican propolis. Their structures were elucidated with spectroscopic analysis. Both compounds (1, 2) exhibited preferential cytotoxic activity against PANC-1 human pancreatic cancer cells in a nutrient-deprived medium with the concentration at which 50% cells died preferentially in NDM (PC₅₀) values of 17.9 μM and 9.1 μM, respectively.

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Mulliken's electronegativity (M) scale was found as a parameterization to predict (elucidate) a virtually specific interaction between Poliovirus proteinase 2A and mitogen-activated protein (MAP) kinase p38α, as well as that between the 2A and apoptotic protein activating factor 1c (Apaf 1c) (or prion) with intermolecular frequency symmetry (IFS) rule. Also, Lacey's hydropathical (H) scale and Garel's (G) one could be found in the specific relationship between the 2A and the extracellular signal-regulated kinase 2 (ERK2) [or fibroblast growth factor receptor 3 (FGFR3)], and that between the 2A and the c-Jun N-terminal kinase 2 (JNK2) [or forkhead box P2-1 (FOXP2-1)], respectively. Based on these, both the same physicochemical scale and almost the same resonant frequency (f) value would be conserved in the same succession of a signal transduction process in a Poliovirus-infected cell. Furthermore, the 2A could play a trigger role to cause cancer, prion disease, bone disease, or speech and language disorder.

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We fabricated novel pH-sensitive polymeric micelles consisting of amphiphilic block copolymer containing pyridyl groups as side chains in the hydrophobic block. The number average particle diameter of the polymeric micelles at pH 7 was approximately 200 nm. A decrease in pH resulted in deformation of the polymeric micelles over a very narrow pH range (between pH 5.7 and 5.6). Interestingly, micellization and demicellization occurred reversibly in this narrow pH range. Polymeric micelles incorporating 5-fluorouracil (5FU) were also prepared. Decreasing the pH of this polymeric micelle solution from 7 to 5.5 resulted in the rapid release of 5FU at pH 5.6; the drug was completely released within 30 min. These results suggest that deformation of the polymeric micelles caused the rapid release of 5FU.

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A new cannabimimetic phenylacetylindole (cannabipiperidiethanone, 1) has been found as an adulterant in a herbal product which contains two other known synthetic cannabinoids, JWH-122 and JWH-081, and which is distributed illegally in Japan. The identification was based on analyses using GC-MS, LC-MS, high-resolution MS and NMR. Accurate mass spectrum measurement showed the protonated molecular ion peak of 1 at m/z 377.2233 [M+H]⁺ and the molecular formula of 1 was C₂₄H₂₉N₂O₂. Both mass and NMR spectrometric data revealed that 1 was 2-(2-methoxyphenyl)-1-{1-[(1-methylpiperidin-2-yl)methyl]-1H-indol-3-yl}ethanone. Compound 1 has a mixed structure of known cannabimimetic compounds: JWH-250 and AM-2233. Namely, the moiety of phenylacetyl indole and N-methylpiperidin-2-yl-methyl correspond to the structure of JWH-250 and AM-2233, respectively. However, no synthetic, chemical or biological information about 1 has been reported. A binding assay of compound 1 to cannabinoid receptors revealed that 1 has affinity for the CB₁ and CB₂ (IC₅₀=591, 968 nM, respectively) receptors, and shows 2.3- and 9.4-fold lower affinities than those of JWH-250. This is the first report to identify cannabimimetic compound (1) as a designer drug and to show its binding affinity to cannabinoid receptors.

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The synthetic utility of N-alkoxyimidoyl halides is demonstrated using the palladium-catalyzed cross-coupling reaction. The Sonogashira and Suzuki–Miyaura coupling reactions of N-alkoxyimidoyl bromides produced versatile ketoxime ethers in good to excellent yields. A one-pot reaction of the imidoyl bromides with arylboronic acid and allylmagnesium bromide to produce N-arylamines via Suzuki–Miyaura coupling followed by domino reaction involving sequential addition-eliminative rearrangement-addition reactions was developed.

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