Chemical and Pharmaceutical Bulletin
Online ISSN : 1347-5223
Print ISSN : 0009-2363
ISSN-L : 0009-2363
Volume 66, Issue 6
Displaying 1-17 of 17 articles from this issue
Regular Articles
  • Tohru Kishino, Yoshihiro Inoue, Kayoko Inoue, Kenichi Saito, Masami Ko ...
    2018 Volume 66 Issue 6 Pages 589-595
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
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    A vaginal suppository containing ulinastatin (UTI) was developed as a hospital pharmacy product from UTI injection solution and Witepsol® S-55. After mixing at 50°C for 0–8 h, UTI suppositories were prepared, which had good UTI content uniformity. Because 2% surfactant was contained in S-55, the UTI injection solution formed a water-in-oil type emulsion as a suppository base. The measured residual moisture content (loss on drying (LOD)) in the prepared vaginal suppositories decreased as the mixing time increased, but their hardness (hardness test (HT)) increased. Near (N) IR spectra of UTI suppositories were measured after mixing for 0–8 h. The best calibration models to predict the HT and LOD of the suppositories were determined based on the NIR spectra by the leave-one-out method in a partial least-squares regression analysis (PLS). The validation result indicated that PLS models for HT and LOD were obtained based on the spectra treated by a combination of smoothing and normalized, respectively, and the model consisted of three latent variables. The plots between the predicted and measured pharmaceutical properties (HT and LOD) based on the calibration data were superimposed with those of the external validation data. The developed NIR spectroscopy method was applied to the preparation process monitoring for UTI vaginal suppositories. In the prepared vaginal suppositories, the predicted LOD decreased as the mixing time increased, and the measured LOD values superimposed well with the predicted values. In contrast, the predicted HT increased as the mixing time increased, and the measured values superimposed with the predicted values.

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  • Yoshio Nakano, Yoshimitsu Katakuse, Yasutaka Azechi
    2018 Volume 66 Issue 6 Pages 596-601
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
    Advance online publication: March 30, 2018
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    An attempt to apply X-Ray Fluorescence (XRF) analysis to evaluate small particle coating process as a Process Analytical Technologies (PAT) was made. The XRF analysis was used to monitor coating level in small particle coating process with at-line manner. The small particle coating process usually consists of multiple coating processes. This study was conducted by a simple coating particles prepared by first coating of a model compound (DL-methionine) and second coating by talc on spherical microcrystalline cellulose cores. The particles with two layered coating are enough to demonstrate the small particle coating process. From the result by the small particle coating process, it was found that the XRF signal played different roles, resulting that XRF signals by first coating (layering) and second coating (mask coating) could demonstrate the extent with different mechanisms for the coating process. Furthermore, the particle coating of the different particle size has also been investigated to evaluate size effect of these coating processes. From these results, it was concluded that the XRF could be used as a PAT in monitoring particle coating processes and become powerful tool in pharmaceutical manufacturing.

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  • Ting-Ting Liang, Qi Zhao, Shan He, Fang-Zhou Mu, Wei Deng, Bing-Nan Ha ...
    2018 Volume 66 Issue 6 Pages 602-607
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
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    Dolastatin 16 is a cyclic depsipeptide isolated from the marine invertebrates and cyanobacterium Lyngbya majuscula, however, its bioactivity has been a historical question. In this study, peptidyl–prolyl cistrans isomerase FKBP1A (FKBP12) was predicted as a potential target of dolastatin 16 via PharmMapper as well as verified using chemical–protein interactome (CPI) and molecular docking. FKBP1A has been previously identified as a target for the natural polyketide FK506 (tacrolimus), an immune suppressor inhibiting the rejection of organ transplantation in clinical use. The comparison study via the reverse pharmacophore screening and molecular docking of dolastatin 16 and FK506 indicated the good consistency of analysis with the computational approach. As the results, the lowest binding energy of dolastatin 16–FKBP1A complex was −7.4 kcal/mol and FK506–FKBP1A complex was −8.7 kcal/mol. The ligand dolastatin 16 formed three hydrogen bonds vs. four of FK506, as well as seven hydrophobic interactions vs. six of FK506 within the active site residues. These functional residues are highly repetitive and consistent with previously reported active site of model of FK506–FKBP1A complex, and the pharmacophore model was shown feasibly matching with the molecular feature of dolastatin 16.

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    Editor's pick

    Dolastatin 16 is a cyclic depsipeptide isolated from cyanobacterium Lyngbya majuscula, however, its bioactivity has been a historical question. In this study, FKBP1A was predicted as a potential target of dolastatin 16 via PharmMapper as well as verified using chemical-protein interactome (CPI) and molecular docking. The lowest binding energy of dolastatin 16-FKBP1A complex was -7.4 kcal/mol. The ligand dolastatin 16 formed three hydrogen bonds and seven hydrophobic interactions within the active site residues. And the pharmacophore model was shown feasibly matching with the molecular feature of dolastatin 16.

  • Jiaxin Li, Yujie Wang, Jian Xue, Pengsi Wang, Shangmei Shi
    2018 Volume 66 Issue 6 Pages 608-611
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
    Advance online publication: March 14, 2018
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    To investigate the dietary exposure risk of flonicamid application on Lonicerae Japonicae Flos and the effect of flonicamid on constituents of Lonicerae Japonicae Flos, field experiments were conducted in Fengqiu, Henan province, and flonicamid residue in samples collected was detected by gas chromatography equipped with electron capture detector (GC-ECD). And chlorogenic acid and luteoloside were determined by HPLC. Dietary exposure risk assessment was conducted through comparing the estimated daily intake (EDI) which was calculated by using the consumed residual level along with the acceptable daily intake (ADI). The effect of flonicamid on chlorogenic acid and luteoloside were obtained by ANOVA statistical analysis and least significant difference (LSD)-t test. The results showed that the terminal-residue contents of flonicamid were under 1.6 mg kg−1. And risk quotient ranged from 0.0011 to 0.0028, indicating the long-term exposure to flonicamid residual through consumption of Lonicerae Japonicae Flos in consumers was relatively low. Flonicamid could suppress the generation of luteoloside, so it was not advised to be used in L. japonica flowering phase. The study aims at providing the useful suggestion on the reasonable flonicamid usage and the reference for the establishment of maximum residue limits (MRLs) of flonicamid in Lonicerae Japonicae Flos.

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  • Qijing Zhang, Jinyun Dong, Jiahua Cui, Guang Huang, Qingqing Meng, Sha ...
    2018 Volume 66 Issue 6 Pages 612-619
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
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    Supplementary material

    In an effort to develop potent and selective antitumor agents, a series of 1,4-naphthoquinone oxime derivatives were designed and synthesized. The cytotoxicity of these compounds were evaluated against five human cancer cell lines (colorectal cancer cell: HCT-15, breast cancer cell: MDA-MB-231, liver cancer cell: BEL-7402, colorectal cancer cell: HCT-116 and ovarian cancer cell: A2780) in vitro. Among them, compound 14 was found to be the most potent cytotoxic compound against three cell lines (MDA-MB-231, BEL-7402 and A2780) with IC50 values of 0.66±0.05, 5.11±0.12 and 8.26±0.22 µM, respectively. Additionally, the length of the side chains and the position of the substituent may also affect the cytotoxic activity of the naphthoquinone oxime derivatives. In general, compound 14 effectively inhibited breast cancer cell proliferation and may become a promising anticancer agent.

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  • Hiroyuki Tsutsumi, Haruka Tanabe, Takashi Ishizu
    2018 Volume 66 Issue 6 Pages 620-623
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
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    A mixture of pharmaceuticals having a xanthine skeleton, theophylline, proxyphylline, diprophylline and (−)-epigallocatechin-3-O-gallate (EGCg) in water created a sticky precipitates, which were thought to be 2 : 2 complexes of the pharmaceuticals and EGCg. The molecular capture ability of the pharmaceuticals having a xanthine skeleton by EGCg was estimated by the amount of the pharmaceuticals included in the precipitates of the complexes, and measured by the integrated value of proton signals in the quantitative 1H-NMR spectra. Based on changes in chemical shifts of proton signals of the pharmaceuticals with a xanthine skeleton in 1H-NMR spectra by adding standard amounts of EGCg, the xanthine skeleton of the pharmaceuticals was considered to exist in the hydrophobic space formed by the three aromatic A, B, B′ rings of EGCg, and a part of the proxyphylline and diprophylline side chains existed out of the hydrophobic space. In the 1H-NMR spectra of the mixture of (R)- and (S)-proxyphylline, (R)- and (S)-diprophylline and an equimolecular amount of EGCg, the N3-CH3 signal of (R)- and (S)-proxyphylline, and (R)- and (S)-diprophylline was clearly observed as two singlets. This suggested that EGCg recognized the chirality of proxyphylline and diprophylline in water.

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  • Yosuke Taniguchi, Mei Miyazaki, Nozomu Matsueda, Lei Wang, Hidenori Ok ...
    2018 Volume 66 Issue 6 Pages 624-631
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
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    The antiparallel triplex DNA is formed by the interaction between purine-rich triplex forming oligonucleotides (TFOs) and the homo-purine region within a duplex DNA. The formation of such a structure with the genome DNA promises to control the gene expression in a living cell. In this study, in an attempt to enhance the stability of the triplex DNAs, we have designed the N2-arylated deoxyguanosine derivatives. Among these analogues, we found that the TFOs containing N2-phenyl-2′-deoxyguanosine (PhdG) showed a stable and selective triplex DNA formation with the GC base pair as compared to the natural dG/GC triplet. However, the multiple incorporation of PhdG into the TFOs hampered the stable triplex DNA, instead, showed a tendency to form a higher order structure. Therefore, we concluded that the stable and selective triplex DNA formation is expected by the replacement of dG by PhdG in the purine-rich TFO sequence.

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    Editor's pick

    The antiparallel triplex DNA is formed by the interaction between purine-rich triplex forming oligonucleotides (TFOs) and the homo-purine region within a duplex DNA. The formation of such a structure with the genome DNA promises to control the gene expression in a living cell. In this paper, in an attempt to enhance the stability of the triplex DNAs, the authors have designed and synthesized the N2-arylated deoxyguanosine derivatives. The TFOs containing N2-phenyl-2′-deoxyguanosine (PhdG) showed a stable and selective triplex DNA formation with the GC base pair as compared to the natural dG/GC triplet.

  • Shuichi Miyamoto, Kenji Atsuyama, Keisuke Ekino, Takashi Shin
    2018 Volume 66 Issue 6 Pages 632-636
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
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    The isolation of useful microbes is one of the traditional approaches for the lead generation in drug discovery. As an effective technique for microbe isolation, we recently developed a multidimensional diffusion-based gradient culture system of microbes. In order to enhance the utility of the system, it is favorable to have diffusion coefficients of nutrients such as sugars in the culture medium beforehand. We have, therefore, built a simple and convenient experimental system that uses agar-gel to observe diffusion. Next, we performed computer simulations—based on random-walk concepts—of the experimental diffusion system and derived correlation formulas that relate observable diffusion data to diffusion coefficients. Finally, we applied these correlation formulas to our experimentally-determined diffusion data to estimate the diffusion coefficients of sugars. Our values for these coefficients agree reasonably well with values published in the literature. The effectiveness of our simple technique, which has elucidated the diffusion coefficients of some molecules which are rarely reported (e.g., galactose, trehalose, and glycerol) is demonstrated by the strong correspondence between the literature values and those obtained in our experiments.

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    Editor's pick

    This article describes the estimation of the diffusion coefficients of sugars and a related compound.  A simple and handy experimental system with agar-gel was built and used to observe diffusion of small molecules. The correlation formulas derived from computer simulations of the experimental diffusion system were then applied to estimate diffusion coefficients. The values obtained for these coefficients agree reasonably well with those published in the literature. This finding supports the efficacy of the approach for estimating diffusion coefficients, leading to the elucidation of the diffusion coefficients of galactose, trehalose and glycerol.

  • Takefumi Kuranaga, Atsuki Fukuba, Akihiro Ninomiya, Kentaro Takada, Sh ...
    2018 Volume 66 Issue 6 Pages 637-641
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
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    Supplementary material

    Surugamide F is a linear decapeptide (1) isolated along with the cyclic octapeptides surugamides A–E (26), from a marine-derived Streptomyces species. The linear peptide 1 is produced by two nonribosomal peptide synthetases (NRPSs) encoded in adjacent open reading frames, which are further flanked by an additional pair of NRPS genes responsible for the biosyntheses of the cyclic peptides 26. While the cyclic peptides 26 were identified to be cathepsin B inhibitors, the biological activity of the new metabolite 1 still remained unclear. In order to elucidate its unique biosynthetic pathway and biological activity in detail, we planned to develop an efficient synthetic route toward 1. Here we report the diastereoselective total synthesis of 1, utilizing 9-fluorenylmethyloxycarbonyl (Fmoc)-based solid-phase peptide synthesis. During this study, we found that the structural correction of 1 was required, due to the mislabeling of the commercially obtained 3-amino-2-methylpropionic acid, and the true structure of 1 was corroborated by the chemical synthesis and chromatographic comparison.

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  • Tomoko Takamiya, Saki Kitamura, Shunichiro Suzuki, Nao Shioda, Yoshifu ...
    2018 Volume 66 Issue 6 Pages 642-650
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
    Advance online publication: April 05, 2018
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    Supplementary material

    Genus Dendrobium (Orchidaceae) contains numerous species. Phylogenetic analyses based on morphological characteristics and DNA sequences indicated that this genus is divided into two major groups: Asian and Australasian clades. On the other hand, little is known about the phytochemical differences and similarities among the species in each clade. In this study, we selected 18 Dendrobium species (11 from the Asian clade and 7 from the Australasian clade) and constructed HPLC profiles, arrays composed of relative intensity of the chromatographic peaks. Next, orthogonal partial least square discriminant analysis (OPLS-DA) was applied to the profile matrix to classify Dendrobium species into the Asian and Australasian clades in order to identify the peaks that significantly contribute to the class separation. In the end, two phenanthrenes, 4,9-dimethoxyphenanthrene-2,5-diol 1 and 1,5-dimethoxyphenanthrene-2,7-diol 2, which contributed to the class separation, were isolated from the HPLC peaks. The existence of 2 was limited to the genetically related Australasian species.

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    Editor's pick

    The genus Dendrobium (Orchidaceae) is comprised of more than 1,000 species and divided into two major groups, Asian and Australasian clades. There are many ethnobotanical important species in this genus and various phenanthrenes and bibenzyl derivatives have been isolated from Dendrobium in previous studies. Secondary metabolites produced by species of the Australasian clade have not been studied well, even though several species of this group have also been used as traditional herbal remedies. The authors provide an overview of secondary metabolites of Dendrobium by combined non-target metabolomics and multivariate analysis, and identified characteristic compounds from several closely related Australasian species.

  • Kazuma Ogawa, Takuya Takeda, Masaru Yokokawa, Jing Yu, Akira Makino, Y ...
    2018 Volume 66 Issue 6 Pages 651-659
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
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    Radiolabeled cyclic peptides containing the (Arg-Gly-Asp) RGD sequence for use in positron emission tomography (PET) imaging, single-photon emission computed tomography (SPECT) imaging, and targeted radionuclide therapy of cancer have been reported. In this study, RGD was used as a model carrier peptide for diagnosis and therapy of cancer. To evaluate the characteristics of radiohalogen-labeled peptides, several kinds of labeled RGD peptides [125I-c(RGDyK), 77Br-c(RGDyK), [125I]SIB-c(RGDfK), [77Br]SBrB-c(RGDfK), [125I]SIB-EG2-c(RGDfK), and [77Br]SBrB-EG2-c(RGDfK)] were designed, prepared, and evaluated. In these initial studies, 77Br (t1/2=57.0 h) and 125I (t1/2=59.4 d) were used because of their longer half-lives. Precursor peptides were synthesized using a standard 9-fluorenylmethyloxycarbonyl (Fmoc)-based solid-phase methodology. Radiolabeled peptides were prepared by chloramine-T method or conjugation of RGD peptides with [125I]N-succinimidyl 3-iodobenzoate ([125I]SIB) or [77Br]N-succinimidyl 3-bromobenzoate ([77Br]SBrB). Measurement of the partition coefficients, integrin binding assay, and biodistribution experiments in tumor-bearing mice were performed. 125I and 77Br labeling were successfully performed using similar methods, and in vitro characteristics and biodistributions were similar between the 125I-labeled and corresponding 77Br-labeled peptides. [125I]SIB- and [77Br]SBrB-conjugated RGD peptides showed higher partition coefficients, lower tumor uptakes, and higher intestinal uptake than 125I-c(RGDyK) and 77Br-c(RGDyK). [125I]SIB-EG2-c(RGDfK) and [77Br]SBrB-EG2-c(RGDfK), which possess an ethylene glycol linker, decreased lipophilicity and uptake in intestine compared with [125I]SIB-c(RGDfK) and [77Br]SBrB-c(RGDfK), which possess no linker. However, the improvement in biodistribution of [125I]SIB-EG2-c(RGDfK) and [77Br]SBrB-EG2-c(RGDfK)] was insufficient. In conclusion, directly radiohalogenated c(RGDyK) peptides are potentially more useful for tumor imaging and therapy than indirectly radiohalogenated ones.

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  • Shotaro Hoshino, Masahiro Ozeki, Chin Piow Wong, Huiping Zhang, Fumiak ...
    2018 Volume 66 Issue 6 Pages 660-667
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
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    Supplementary material

    Mycolic acid-containing bacteria (MACB) are known to activate cryptic natural product biosynthesis in co-cultures with actinobacteria. We cultured Actinosynnema mirum NBRC 14064, a producer of the mono-cyclic polyene macrolactam mirilactam A (6), with the MACB Tsukamurella pulmonis TP-B0596. As a result, three novel compounds (mirilactams C–E, 1–3) were produced in the co-culture conditions. Compounds 1–3 were likely derived from 6 by epoxidation and subsequent spontaneous cyclization. The chemical structures and stereochemistries of 1–3 were determined by spectroscopic analyses (NMR and MS), conformational searches in the optimized potentials for liquid simulations-3 (OPLS3) force field, and calculations of electronic circular dichroism (ECD).

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    Editor's pick

    Actinobacteria are the rich source of natural products while the large parts of biosynthetic gene clusters (BGCs) are silent under the standard culture conditions. The authors previously demonstrated that co-culture with mycolic acid-containing bacterium (MACB) effectively activates the silent BGCs in actinobacteria. In this study, the authors investigated the actinobacterium which produces a polyene macrolactam, mirilactam A. The authors tested co-culture of the mirilactam A producer strain with MACB, and successfully obtained three novel polycyclic macrolactams, mirilactams C-E, by activating silent biosynthetic genes responsible for the epoxidation and cyclization of the polyene mirilactam A.

  • Yoshinori Saito, Yuko Shiosaki, Miho Fujiwara, Kanako Mihara, Hiromi N ...
    2018 Volume 66 Issue 6 Pages 668-673
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
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    Chemical constituents of Ligularia hookeri (Asteraceae) collected in Yunnan and Sichuan Provinces in China were examined for the first time. Seven furanoeremophilanes, five of which were new, as well as known bisabolane- and eudesmane-type sesquiterpenoids, were isolated. Spectroscopic evidence indicates that the previously reported 3β-(2′-methylpropenoyloxy)furanoeremophilan-15,6β-olide should be revised to 3β-(2′-methylpropenoyloxy)furanoeremophilan-15,6α-olide.

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Notes
  • Jia-Xi Wang, Qian Wang, Yong-Qi Zhen, Shuang-Mei Zhao, Feng Gao, Xian- ...
    2018 Volume 66 Issue 6 Pages 674-677
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
    Advance online publication: March 27, 2018
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    Supplementary material

    We isolated two new lathyrane-type diterpenes L27 (1) and L28 (2) along with seven known compounds (39) from the seeds of Euphorbia lathyris. These compounds were identified by NMR, high-resolution electrospray ionisation (HR-ESI)-MS as well as IR spectroscopy. Compounds 1 and 2 were assigned NMR spectrums with 1H-NMR, 13C-NMR, distortionless enhancement by polarization (DEPT), correlation spectroscopy (COSY), heteronuclear multiple quantum coherence (HMQC), heteronuclear multiple bond connectivity (HMBC) and nuclear Overhauser effect spectroscopy (NOESY). Stereo configuration of 1 and 2 were confirmed by comprehensive interpretation of their nuclear Overhauser effect (NOE) relationship and showed they were first natural lathyrane-type diterpenes possessing α-configuration substitutes at C-3. Cytotoxicity assay of isolated compounds were evaluated against breast cancer cell lines MCF-7 or MDA-MB-231, 786-0 and liver cancer cell lines HepG2. As a result, Euphorbia factor L28 (2) showed strongly cytotoxicity to the 786-0 and HepG2 cell lines, with an IC50 value of 9.43 and 13.22 µM, respectively, which preliminarily suggested that the configuration of lathyrane-type diterpene at C-3 has a significant effect on its bioactivity.

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  • Ryosuke Koyama, Wataru Hakamata, Takako Hirano, Toshiyuki Nishio
    2018 Volume 66 Issue 6 Pages 678-681
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
    Advance online publication: March 13, 2018
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    Supplementary material

    Three Golgi mannosidases (GMs), namely Golgi α-mannosidases IA, IB, and IC, remove mannose residues from N-glycans and regulate the quality control and transportation of nascent proteins. GM inhibitors regulate several biological events such as cell–cell communication, differentiation, and apoptosis in cancer cells. As a result, GM inhibitor-based therapies have gained significant attention for cancer treatment. However, to date, no GM inhibitor has been approved and none is in clinical development for anti-cancer treatment. Meanwhile, drug repositioning plays an important role in identifying potential inhibitors that vary in molecular structure and properties to bypass much of the early cost and time. We performed a drug repositioning screen of a compound library that included approved drugs. The estrogen receptor antagonists tamoxifen and raloxifene inhibited human GMs at the cellular level. Sulindac, a nonsteroidal anti-inflammatory drug, also inhibited GMs. Our results demonstrated the efficacy of this screening strategy and revealed lead compounds for anti-cancer drug development.

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  • Delfly Booby Abdjul, Hiroyuki Yamazaki, Syu-ichi Kanno, Ryota Kirikosh ...
    2018 Volume 66 Issue 6 Pages 682-687
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
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    Two sesquiterpene lactones with the (9R)-eudesman-9,12-olide framework, wedelolides I and J, have been isolated together with five eudesmanolide sesquiterpenes and twelve ent-kaurene diterpenes from the aerial parts of Indonesian Wedelia prostrata. The absolute configurations of wedelolides I and J, proposed in the previous communication, were proven by comparing their experimental Electronic Circular Dichroism (ECD) spectra with the calculated ECD spectrum of wedelolide I. The phytochemical study on the aerial parts of Okinawan Wedelia chinensis led to the isolation of three other eudesmanolide sesquiterpenes in addition to the three sesquiterpenes and eleven diterpenes isolated from the Indonesian W. prostrata as above. However, the wedelolide derivatives found in the Indonesian plant were not detected. Among these compounds, most of the diterpenes inhibited protein tyrosine phosphatase (PTP) 1B activity, and a structure–activity relationship study revealed that the cinnamoyl group enhanced inhibitory activity. Therefore, two ent-kaurene derivatives with and without a cinnamoyl group were examined for the ability to accumulate phosphorylated-Akt (p-Akt) because PTP1B dephosphorylates signal transduction from the insulin receptor such as phosphorylated Akt, a key downstream effector. However, neither compound enhanced insulin-stimulated p-Akt levels in two human hepatoma cell lines (Huh-7 and HepG2) at non-cytotoxic doses.

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  • Sota Masakado, Yusuke Kobayashi, Yoshiji Takemoto
    2018 Volume 66 Issue 6 Pages 688-690
    Published: June 01, 2018
    Released on J-STAGE: June 01, 2018
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    Supplementary material

    Activation of N-sulfonyliminiodinanes was achieved by photo-irradiation at 375 nm, which enabled the reaction with several alkenes to afford the corresponding aziridines. Mechanistic studies suggested that the reaction would proceed through a stepwise mechanism via radical intermediates rather than through a concerted process.

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