著者

Hidetomo Yokoo Eiichi Yamamoto Sayaka Masada Nahoko Uchiyama Genichiro Tsuji Takashi Hakamatsuka Yosuke Demizu Ken-ichi Izutsu Yukihiro Goda

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.69, no.9, pp.872-876, 2021-09-01 (Released:2021-09-01)

参考文献数

23

被引用文献数

13

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N-Nitrosodimethylamine (NDMA) is a probable human carcinogen. This study investigated the root cause of the presence of NDMA in ranitidine hydrochloride. Forced thermal degradation studies of ranitidine hydrochloride and its inherent impurities (Imps. A, B, C, D, E, F, G, H, I, J, and K) listed in the European and United States Pharmacopeias revealed that in addition to ranitidine, Imps. A, C, D, E, H, and I produce NDMA at different rates in a solid or an oily liquid state. The rate of NDMA formation from amorphous Imps. A, C, and E was 100 times higher than that from crystalline ranitidine hydrochloride under forced degradation at 110 °C for 1 h. Surprisingly, crystalline Imp. H, bearing neither the N,N-dialkyl-2-nitroethene-1,1-diamine moiety nor a dimethylamino group, also generated NDMA in the solid state, while Imp. I, as an oily liquid, favorably produced NDMA at moderate temperatures (e.g., 50 °C). Therefore, strict control of the aforementioned specific impurities in ranitidine hydrochloride during manufacturing and storage allows appropriate control of NDMA in ranitidine and its pharmaceutical products. Understanding the pathways of the stability related NDMA formation enables improved control of the pharmaceuticals to mitigate this risk.

著者

Toshihiko Ishizaka Sachie Okada Emi Tokuyama Junji Mukai Takahiro Uchida

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.56, no.10, pp.1395-1399, 2008-10-01 (Released:2008-10-01)

参考文献数

18

被引用文献数

9 10

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The aim of the study was to suppress the bitterness and improve the palatability of pediatric prednisolone powder (PP) by the addition of simple sucrose syrup (SS) and various beverages and foods. Bitterness suppression was evaluated using the human gustatory sensory test. The suppression of the bitterness and improvement of palatability of PP by addition of SS solutions was investigated using standard taste substances: sucrose for sweetness, tartaric acid for sourness, and sodium chloride as saltiness. Dilution with SS solutions of up to 50% (w/w) was successful in bitterness-suppression and improvement of palatability, but at 80% (w/w) SS, the palatability of the diluted solution was reduced. The kinematic viscosities of SS solutions were therefore evaluated using the Uberorde viscosity meter, to see whether the high viscosity of the more concentrated solutions was responsible for the reduced palatability. The kinematic viscosity of the 80% SS was 16.60 mm2/s. Judging from above information, the palatability might become worse when the kinematic viscosity of syrup exceeded 15 mm2/s. Finally, the ability of various beverages and foods with low viscosity to suppress the bitterness and improve the palatability of PP were examined. The additions of orange juice or a carbonated lemon drink to simple syrup solution were most effective in suppressing bitterness and improving palatability of PP.

著者

Kounosuke Oisaki

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.66, no.10, pp.907-919, 2018-10-01 (Released:2018-10-01)

参考文献数

40

被引用文献数

1

---

To conduct organic synthesis in the field of pharmaceutical science, methodologies that can easily and quickly supply compounds with high drug-likeness are highly desirable. Based on the original catalyst design concept “Radical-Conjugated Redox Catalysis (RCRC)” established during my research, various C(sp3)–H functionalizations and protein modifications have been developed, taking advantage of the high reactivity and chemoselectivity of the single-electron transfer process. This review focuses on the eight-year research efforts by my collaborators and me, from conception to results.

著者

Noriko Saito-Tarashima Akiho Murai Noriaki Minakawa

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.70, no.5, pp.310-315, 2022-05-01 (Released:2022-05-01)

参考文献数

59

---

DNA and RNA are ubiquitous molecules responsible for storage and transmission of genetic information and together comprise the central dogma of molecular biology. However, the recent emergence of synthetic genetic polymers is providing an opportunity to challenge the fundamental principles of life. Herein, we describe the ongoing attempts to rewrite the central dogma with 4′-thioDNA and 4′-thioRNA, which feature a sulfur instead of an oxygen atom in the furanose ring moiety. Using reconstituted Escherichia coli gene expression machinery, studies have shown that the genetic information conserved in 4′-thioDNA can be transcribed to 4′-thioRNA and eventually translated into protein, mirroring the processes that occur in nature. Such studies underscore the feasibility of controlling life by substances other than DNA and RNA.

著者

Md Mahadi Hassan Ahmed Fouad Abdelwahab Mohammed Khaled M. Elamin Hari Prasad Devkota Yoshitaka Ohno Keiichi Motoyama Taishi Higashi Teruko Imai

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.68, no.11, pp.1117-1120, 2020-11-01 (Released:2020-11-01)

参考文献数

7

被引用文献数

5

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Zerumbone is a multifunctional compound which shows various biological activities, such as antitumor activity, anti-inflammatory activity, antiulcer activity, etc. However, to use Zerumbone as functional foods or medicines, its pharmaceutical properties such as solubility should be improved. In the present study, we prepared its inclusion complexes with various cyclodextrin (CyD) derivatives, and evaluated their solubility, release profile of the drug and cytotoxic activity. Among 11 CyDs, sulfobutylether (SBE)-β-CyD showed the highest solubilizing effect for Zerumbone. Phase solubility diagrams of SBE-β-CyD/Zerumbone in 10% methanol solution showed AL type, and the stability constant was 756 M−1. SBE-β-CyD also formed the solid complex with Zerumbone by kneading for 90 min. Importantly, the dissolution rate of Zerumbone was improved by complexation with SBE-β- and hydroxypropyl (HP)-β-CyDs, and its supersaturation was maintained for several hours. The solubilizing effects by SBE-β-CyD was greater than that of HP-β-CyD. Moreover, SBE-β-CyD/Zerumbone complex also retained the cytotoxic activity of Zerumbone. These results suggest that CyDs, especially SBE-β-CyD, were useful to improve the solubility of Zerumbone.

著者

Kouichi Yoshizaki Hari Prasad Devkota Hiroharu Fujino Shoji Yahara

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.61, no.3, pp.344-350, 2013-03-01 (Released:2013-03-01)

参考文献数

24

被引用文献数

9 24

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A new dammarane-type triterpenoid saponin, chikusetsusaponin VII (1), and nineteen known triterpenoid saponins, ginsenoside Rb1 (2), ginsenoside Rb3 (3), ginsenoside Rc (4), ginsenoside Rd (5), ginsenoside Re (6), ginsenoside Rg1 (7), ginsenoside Rg2 (8), ginsenoside Rh1 (9), notoginsenoside R1 (10), notoginsenoside R2 (11), notoginsenoside Fe (12), chikusetsusaponin IVa (13), chikusetsusaponin IV (14), chikusetsusaponin V (15), chikusetsusaponin VI (16), chikusetsusaponin FK6 (17), gypenoside XVII (18), 28-desglucosylchikusetsusaponin IV (19), and zingibroside R1 (20), were isolated from rhizomes, taproots, and lateral roots of Panax japonicus C. A. Meyer, so-called “Satsuma-ninjin,” grown in southern Miyazaki Prefecture, Japan. The structure of new chikusetsusaponin VII was elucidated on the basis of spectral and physicochemical evidence. Although the chemical composition of the rhizome was found to be similar to that of the “Chikusetsu-ninjin,” the saponin composition of lateral root of “Satsuma-ninjin” was found to be close to that of lateral root of P. ginseng. The total yield of oleanolic acid saponins of the taproot was less than that of rhizome, but the total yield of dammarane-type saponins of the taproot was found to be similar to that of rhizome.

著者

Yujiro Kameyama Maki Matsuhama Chie Mizumaru Rieko Saito Tsuyoshi Ando Seiko Miyazaki

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.67, no.12, pp.1301-1313, 2019-12-01 (Released:2019-12-01)

参考文献数

60

被引用文献数

13

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A pharmacopoeia’s core mission is to protect public health by creating and making available public standards to help ensure the quality of drugs. In recent years, pharmacopoeias around the world have harmonized their standards in the present context of globalized drug supply chains and markets. For example, the Pharmacopoeial Discussion Group has worked to harmonize excipient monographs and general chapters. In addition, the International Meeting of World Pharmacopoeias has been held by the WHO to discuss information exchange and international collaboration, among other topics. To contribute further to the protection of public health in the globalized drug market, we conducted a comparative study of the pharmacopoeias in Japan, Europe, and the United States. We aimed to examine current differences among the Japanese Pharmacopoeia, the European Pharmacopoeia, and the United States Pharmacopeia–National Formulary and to identify areas that require further collaboration among the three pharmacopoeias. In this study, we analyzed monographs and general chapters listed in the three pharmacopoeias. We identified the features of the monographs and general chapters listed in each pharmacopoeia, as well as differences across the pharmacopoeias. Moreover, on the basis of our findings, we suggest standards that require further collaboration among the pharmacopoeias in certain preferred areas. The comparison data produced by this study are expected to be used to develop strategies for future revisions of pharmacopoeias around the world.

著者

Khem Raj Joshi Hari Prasad Devkota Takashi Watanabe Shoji Yahara

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.62, no.2, pp.191-195, 2014-02-01 (Released:2014-02-01)

参考文献数

24

被引用文献数

4 5

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Three new glycosides: thotneoside A (quercetin 3-O-(6″-O-phenylacetyl)-β-D-galactopyranoside) (1), thotneoside B (quercetin 3-O-(6″-O-phenylacetyl)-β-D-glucopyranoside) (2) and thotneoside C (3-methyl-2-butenoic acid 1-O-β-D-glucopyranoside) (3), together with nine known compounds; quercetin (4), quercetin 3-O-β-D-galactopyranoside (5), quercetin 3-O-(6″-O-galloyl)-β-D-galactopyranoside (6), quercetin 3-O-β-D-galacturonopyranoside (7), quercetin 3-O-β-D-glucuronopyranoside (8), quercetin 3-O-α-L-rhamnopyranoside (9), rutin (10), quercetin 3-O-α-L-arabinopyranoside (11) and 2,4,6-trihydroxyacetophenone 2-O-β-D-glucopyranoside (12) have been isolated from the shade dried leaves of Aconogonon molle, commonly known as “Thotne″ in Nepal. The structures were elucidated on the basis of chemical and spectroscopic methods. All of these compounds were isolated for the first time from A. molle and their in vitro antioxidant activity was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay. Quercetin (4) and its glycosides (1–2, 5–11) showed potent free radical scavenging activity.

著者

Marie Kurihara Vera Thiel Hirona Takahashi Keiichi Kojima David M. Ward Donald A. Bryant Makoto Sakai Susumu Yoshizawa Yuki Sudo

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.71, no.2, pp.154-164, 2023-02-01 (Released:2023-02-01)

参考文献数

45

被引用文献数

1

---

Rhodopsins are transmembrane proteins with retinal chromophores that are involved in photo-energy conversion and photo-signal transduction in diverse organisms. In this study, we newly identified and characterized a rhodopsin from a thermophilic bacterium, Bellilinea sp. Recombinant Escherichia coli cells expressing the rhodopsin showed light-induced alkalization of the medium only in the presence of sodium ions (Na+), and the alkalization signal was enhanced by addition of a protonophore, indicating an outward Na+ pump function across the cellular membrane. Thus, we named the protein Bellilinea Na+-pumping rhodopsin, BeNaR. Of note, its Na+-pumping activity is significantly greater than that of the known Na+-pumping rhodopsin, KR2. We further characterized its photochemical properties as follows: (i) Visible spectroscopy and HPLC revealed that BeNaR has an absorption maximum at 524 nm with predominantly (>96%) the all-trans retinal conformer. (ii) Time-dependent thermal denaturation experiments revealed that BeNaR showed high thermal stability. (iii) The time-resolved flash-photolysis in the nanosecond to millisecond time domains revealed the presence of four kinetically distinctive photointermediates, K, L, M and O. (iv) Mutational analysis revealed that Asp101, which acts as a counterion, and Asp230 around the retinal were essential for the Na+-pumping activity. From the results, we propose a model for the outward Na+-pumping mechanism of BeNaR. The efficient Na+-pumping activity of BeNaR and its high stability make it a useful model both for ion transporters and optogenetics tools.

著者

Tatsuya Fukuta Kentaro Kogure

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.70, no.5, pp.334-340, 2022-05-01 (Released:2022-05-01)

参考文献数

53

被引用文献数

9

---

Targeted drug delivery using nanoparticles has been applied for the treatment of diverse diseases, including cancer and inflammatory diseases. Nanoparticle-mediated delivery of therapeutic agents via the enhanced permeability and retention effect generally augments their therapeutic efficiency; however, limitations with passive entry of nanoparticles into diseased sites, due to the presence of biological barriers represented by the endothelial layer, remain to be addressed. To this end, development of nanoparticles with intrinsic characteristics similar to circulatory cells (e.g., leukocytes, platelets) for use as biomimetic drug delivery systems (DDS) has been focused as a means to overcome the issues of conventional DDS. In particular, synthetic biomimetic nanoparticles coated with cellular membranes were recently prepared and shown to actively overcome the inflamed vessels and tumor microenvironment as a result of the functionality of membrane proteins, which allowed secure drug delivery into diseased sites. We recently developed liposomes modified with leukocyte membrane proteins via intermembrane protein transfer, a simple method to reconstitute cellular membrane proteins onto lipid bilayers. The resultant liposomes demonstrated the ability to cross the inflamed endothelial layer and permeate into tumor tissue by mimicking the properties of leukocytes. Thus, biomimetic DDS offer promise as new therapeutic approaches for various diseases by overcoming biological barriers that typically inhibit drug delivery. Herein, we review recent approaches to develop biomimetic DDS using the cell membrane coating method, and highlight our recent findings on leukocyte-mimetic liposomes prepared via intermembrane protein transfer.

著者

Kiyosei Takasu

出版者

公益社団法人日本薬学会

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.64, no.7, pp.656-667, 2016-07-01 (Released:2016-07-01)

参考文献数

68

被引用文献数

1 12

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The search for new drugs that could treat tropical protozoan diseases, such as malaria or neglected tropical diseases (NTDs), motivates many medicinal chemists. New classes of antiprotozoal drugs that act through a novel mechanism of action must be developed. This review presents our efforts toward finding new candidate treatments for malaria, American trypanosomiasis, human African trypanosomiasis and leishmaniasis based on π-delocalized lipophilic cations (DLCs). DLCs, such as rhodacyanines, azarhodacyanines, β-carbolinium salts, and phenoxazinium salts, displayed strong antiprotozoal activities with highly selective indices. Several DLCs displayed moderate to excellent in vivo efficacies against Plasmodium berghei when administered intraperitoneally or orally. This review also discusses chemical biology approaches to understanding the mechanism of action underlying the antimalarial rhodacyanines.

著者

Keita Yaginuma Shuichi Tanabe Manabu Kano

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.70, no.1, pp.74-81, 2022-01-01 (Released:2022-01-01)

参考文献数

23

被引用文献数

1

---

Soft sensors are powerful tools for the implementation of process analytical technology (PAT). They are categorized into white-box (first-principle), black-box (statistical), and gray-box models. Gray-box models integrate white-box and black-box models to address each drawback, i.e., prediction accuracy and intuitiveness. Although they have been applied to various industrial processes, their applicability to water content monitoring in fluidized bed granulation has not been reported. In this study, we evaluated three types of gray-box models, i.e., parallel, serial, and combined gray-box models, in terms of prediction accuracy using real operating data on a commercial scale with two formulations. The gray-box models were constructed by integrating the heat and mass balance model (white-box model) and locally weighted partial least squares regression (LW-PLSR) model (black-box model). LW-PLSR was utilized to cope with collinearity and nonlinearity. In the serial gray-box models, LW-PLSR models adjusted the fitting parameters of the white-box model depending on the process parameters for each query. In the parallel gray-box or combined gray-box models, LW-PLSR models compensated for the output error of the white-box or serial gray-box models, respectively. The results demonstrated that all three types of gray-box models improved the prediction accuracy of the white-box models regardless of the formulation. Besides, we proposed the assessment method based on Hotelling’s T2 and Q residual for gray-box models using LW-PLSR, which contributes decision support to select gray-box or white-box model. The accurate and descriptive gray-box models are expected to enhance process understanding and precise quality control in fluidized bed granulation.

著者

Merve Ergül Ahmet Şevki Taşkıran

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.69, no.9, pp.832-839, 2021-09-01 (Released:2021-09-01)

参考文献数

36

被引用文献数

9

---

Thiamine (vitamin B1), which is synthesized only in bacteria, fungi and plants and which humans should take with diet, participates in basic biochemical and physiological processes in a versatile way and its deficiency is associated with neurological problems accompanied by cognitive dysfunctions. The rat glioblastoma (C6) model was used, which was exposed to a limited environment and toxicity with glutamate. The cells were stressed by exposure to glutamate in the presence and absence of thiamine. The difference in cell proliferation was evaluated in the XTT assay. Oxidative stress (OS) markers malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) levels, as well as endoplasmic reticulum (ER) stress markers 78-kDa glucose-regulated protein (GRP78), activating transcription factor-4 (ATF-4), and C/EBP homologous protein (CHOP) levels, were measured with commercial kits. Apoptosis determined by flow cytometry was confirmed by 4′,6-diamidino-2-phenylindole (DAPI) staining. At all concentrations, thiamine protects the cells and increased the viability against glutamate-induced toxicity. Thiamine also significantly decreased the levels of MDA, while increasing SOD and CAT levels. Moreover, thiamine reduced ER stress proteins’ levels. Moreover, it lessened the apoptotic cell amount and enhanced the live-cell percentage in the flow cytometry and DAPI staining. As a result, thiamine may be beneficial nutritional support for individuals with a predisposition to neurodegenerative disorders due to its protective effect on glutamate cytotoxicity in glioblastoma cells by suppressing OS and ER stress.

著者

塚本 博樹 久田 末雄 西部 三省

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.33, no.9, pp.4069-4073, 1985-09-25 (Released:2008-03-31)

参考文献数

30

被引用文献数

41 45

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Two biologically active coumarins, scopoletin (1) and isofraxidin (2), along with known coumarins, esculetin (3), fraxetin (4), esculin (5) and fraxin (6), were newly isolated from the bark of Fraxinus japonica BLUME (Oleaceae). On the other hand, the bark of F. mandshurica RUPR. var. japonica MAXIM gave only known coumarins, fraxetin (4), fraxinol (7) and mandshurin (8).

著者

Misaki Nakano Rikako Nakamura Yuto Sumida Kazunori Nagao Taniyuki Furuyama Fuyuhiko Inagaki Hirohisa Ohmiya

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.69, no.6, pp.526-528, 2021-06-01 (Released:2021-06-01)

参考文献数

22

被引用文献数

2

---

The optical property of fluorescent unit-conjugated aliphatic oxaboroles has been investigated. The oxaboroles provide good fluorescence quantum yields and selective recognition toward D-ribose and D-ribose containing molecules. The molecular recognition induced significant fluorescence quenching. The property of the boroles showed the possibility of the boron-based nicotinamide adenine dinucleotide (NAD) sensor probe.

著者

Hironori Takeuchi Yoshihiro Ueda Takumi Furuta Takeo Kawabata

出版者

公益社団法人日本薬学会

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.65, no.1, pp.25-32, 2017-01-01 (Released:2017-01-01)

参考文献数

27

被引用文献数

22

---

A short-step total synthesis of the natural glycosides pterocarinin C and tellimagrandin II (eugeniin) has been performed by sequential and site-selective functionalization of free hydroxy groups of unprotected D-glucose. The key reactions are β-selective glycosidation of a gallic acid derivative using unprotected D-glucose as a glycosyl donor and catalyst-controlled site-selective introduction of a galloyl group into the inherently less reactive hydroxy group of the glucoside.

著者

Miyako Yoshida Honami Kojima Atsushi Uda Tamami Haraguchi Minoru Ozeki Ikuo Kawasaki Kazuhiro Yamamoto Ikuko Yano Midori Hirai Takahiro Uchida

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.67, no.5, pp.404-409, 2019-05-01 (Released:2019-05-01)

参考文献数

30

被引用文献数

9 9

---

The purpose of the study was to evaluate the ability of different beverages to mask the bitterness of zopiclone and eszopiclone in tablet formulations using the artificial taste sensor and human gustatory sensation testing. The beverages tested for bitterness-masking effects were: Mugicha, Sports beverage, Lactic acid drink, Orange juice and a diluted simple syrup (an 8.5% sucrose solution). The bitterness intensities estimated by the taste sensor of zopiclone or eszopiclone one-tablet solutions mixed with the various beverages, corresponded well with the observed bitterness intensities measured by gustatory sensation testing. The Sports beverage, Lactic acid drink and Orange juice significantly suppressed the bitterness intensity of both zopiclone and eszopiclone 1-tablet solutions compared with water when tested in the artificial taste sensor. Sports beverage, Lactic acid drink and Orange juice all contain citric acid as acidifier, so it was postulated that citric acid was involved in the mechanism of bitterness intensity suppression of zopiclone and eszopiclone 1-tablet solutions by these three beverages. It was then shown that citric acid suppressed the bitterness intensity of a zopiclone one-tablet sample solution in a dose-dependent manner. 1H-NMR spectroscopic analysis of mixtures of citric acid with zopiclone suggested that the carboxyl groups of citric acid interact with the amine group on zopiclone. This study therefore showed that the bitterness intensities of zopiclone and eszopiclone can be suppressed by citric-acid-contained beverages and suggests that this bitterness suppression is due to a direct electrostatic interaction between citric acid and the two drugs.

著者

Lu Lin Shunsuke Kataoka Kiichi Hirayama Ryozo Shibuya Kenji Watanabe Hiroyuki Morimoto Takashi Ohshima

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.71, no.2, pp.101-106, 2023-02-01 (Released:2023-02-01)

参考文献数

53

---

Catalytic control of chemoselectivity is crucial in the synthesis of highly functionalized compounds. Although there are reports of efficient chemoselective reactions of alcohols and amines as nucleophiles, there are no reports of the chemoselective activation of alcohols and amines as electrophiles. In this study, highly O- and N-selective electrophilic activation of allylic alcohols and amines was achieved in Pd-catalyzed direct allylic alkylation. Allylamines were inherently more reactive than allylic alcohols (N-selectivity). On the other hand, the addition of catalytic amounts of 9-phenanthreneboronic acid preferentially activated allylic alcohols over allylamines (O-selectivity). Density functional theory (DFT) calculations suggested that the N-selectivity is due to the selective activation of allylic amines with ammonium cations, and boronate formation accelerates the activation of allylic alcohols.

著者

Toshihiko Tashima

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.68, no.4, pp.316-325, 2020-04-01 (Released:2020-04-01)

参考文献数

59

被引用文献数

23 55

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Discriminatory drug delivery into target cells is essential to effectively elicit the drug activity and to avoid off-target side effects; however, transporting drugs across the cell membrane is difficult due to factors such as molecular size, hydrophilicity, intercellular adhesiveness, and efflux transporters, particularly, in the brain capillary endothelial cells. Drug delivery into the brain is blocked by the blood–brain barrier (BBB). Thus, developing drugs for the central nervous system (CNS) diseases remains a challenge. The approach based on receptor-mediated transcytosis (RMT) can overcome this impassable problem at the BBB. Well-designed molecules for RMT form conjugates with the ligand and drugs via linkers or nanoparticles. Cell penetrating peptides (CPPs), receptor-targeting peptides, and monoclonal antibodies (mAbs) are often used as ligands. The binding of ligand to the receptor on the endothelial cell surface induces endocytosis. Existing exosomes comprising the conjugates move in the cytoplasm and fuse with the opposite plasma membrane to release them. Subsequently, the transcytosed conjugate-loaded drugs or released drugs from the conjugates elicit activity in the brain. As receptors, transferrin receptor (TfR), low-density lipoprotein receptor (LDLR), and insulin receptor (InsR) have been used to intendedly induce transcytosis. Presently, several clinical trials on CNS drugs for Alzheimer’s and Parkinson disease are hindered due to poor drug distribution into the brain. Therefore, this strategy based on RMT is a promising method for CNS drugs to be transported into the brain. In this review, I introduce the practicality and possibility of drug delivery into brain across the BBB using RMT.

著者

Koyo Nishida

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.68, no.7, pp.559, 2020-07-01 (Released:2020-07-01)