Prepress

Regular & Special Issues

16 data found. 1 - 16 listed

Published online: 12th July, 2019

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14093
■ A Convenient Approach to the Synthesis of Novel Tricyclic Fused Furo[2,3-b]pyridine Derivatives

Fumi Okabe-Nakahara,* Kazuhiro Tomoike, Hayate Nagabuchi, Eiichi Masumoto, Hiroshi Maruoka, and Kenji Yamagata

*Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan

Abstract

The synthesis of novel tricyclic fused furo[2,3-b]pyridine derivatives is described. 3-Cyano-4,5-dihydro-2-furan(and 2-thiophene)acetonitriles 1,2 were reacted with phenacyl bromides to give 5'-arylfuran-2'-amines 3,4. Compounds 3,4 were intramolecularly cyclized in the presence of sodium ethoxide to yield tricyclic fused furo[2,3-b]pyridine derivatives 5,6. Furthermore, one-pot synthesis of compounds 5,6 from starting materials 1,2 is also developed.

FREE:PDF (317KB)

Published online: 12th July, 2019

Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14100
■ Synthesis of Arylthiochlorocyclotriphosphazenes

Manabu Kuroboshi,* Masaki Mikasa, and Hideo Tanaka

*Graduate School of Natural Science and Technology, Okayama University, Tsushima-naka 3-1-1, Kita-ku, Okayama 700-7530, Japan

Abstract

We investigated the reaction between hexachlorocyclotriphosphazene ((NPCl2)3: HCCP) and thiols in the presence of bases. In MeCN/Et3N, two and/or four arylthio units were introduced in gem-mode selectively by controlling the amount of thiols: thus, HCCP was treated with 2 and/or 4 equivalents of ArSH/Et3N in MeCN to afford 2,2-dithiolated and/or 2,2,4,4-tetrathiolated products, respectively. Neither mono-thiosubstituted products, tri-thiosubstituted products, nor regioisomers (non-geminal products) were obtained. In contrast, when other solvents such as THF and Et2O or other bases such as NaH or K2CO3 were used, a mixture of dithiolated products, tetrathiolated products, and hexathiolated products was obtained.

FREE:PDF (995KB)

Published online: 9th July, 2019

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14108
■ Semisynthesis of Triptolide Analogues Part IV: Effects of C-14 Carbamothioate Substituents on Cytotoxic Activities

Yutaka Aoyagi,* Mizuki Murase, Chihiro Kuwahara, Reiko Yano, Ritsuo Aiyama, Takeshi Matsuzaki, Shusuke Hashimoto, Haruhiko Fukaya, Koichi Takeya, and Yukio Hitotsuyanagi*

*College of Pharmacy, Kinjo Gakuin University, 2-1723 Omori, Moriyama-ku, Nagoya 463-8521, Japan

Abstract

Four C-14 carbamothioate triptolide analogues were prepared and their cytotoxic activities on A549 human lung tumor cells and HT29 human colon tumor cells were evaluated. The activities of the prepared compounds were weaker than those of the parent compound, triptolide (1). However, some differences were noted in the activities of prepared compounds. The leaving ability and bulkiness of the amine components of their carbamothioate groups appeared to affect their cytotoxic activities.

FREE:Supporting Info. (785KB)PDF (454KB)

Published online: 5th July, 2019

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14109
■ Fragilides M–O, New Triacetoxybriaranes from the Gorgonian Coral Junceella fragilis (Ellisellidae)

Chia-Cheng Lin, Wu-Fu Chen, Gene-Hsiang Lee, Zhi-Hong Wen, Lee-Shing Fang, Yueh-Hsiung Kuo, Chieh-Yu Lee,* and Ping-Jyun Sung*

*Department of Planning and Research, National Museum of Marine Biology and Aquarium, 2 Houwan Road, Checheng, Pingtung, Taiwan 944, Taiwan

Abstract

Chemical investigation of the EtOAc-soluble fraction from the methanol/dichloromethane extract of a sea whip gorgonian coral Junceella fragilis afforded four polyacetoxybriaranes, including a known metabolite, junceellin (1), along with three new analogues, fragilides M–O (2–4). The absolute configuration of 1 was determined by X-ray analysis and the structures of 2–4 were elucidated on the basis of spectroscopic methods.

FREE:Supporting Info. (2.2MB)PDF (1.6MB)

Published online: 1st July, 2019

Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14099
■ Synthesis of Aminated Cyclotriphosphazenes. Solvent Effects on the Product-Selectivity of the Amination

Manabu Kuroboshi,* Masahiko Morita, Yasunari Masumoto, Masaki Mikasa, Ryohei Toza, and Hideo Tanaka

*Graduate School of Natural Science and Technology, Okayama University, Tsushima-naka 3-1-1, Kita-ku, Okayama 700-7530, Japan.

Abstract

We investigated the reaction between hexachlorocyclotriphosphazene ((NPCl2)3) and gaseous ammonia in several solvents to find that (NPCl2)2(NP(NH2)2) was obtained in solvents having low dielectric constant such as toluene and ether, whereas novel compound, (NPCl2)(NP(NH2)2)2, was selectively obtained in solvents having high dielectric constant such as acetonitrile.

FREE:PDF (606KB)

Published online: 20th June, 2019

Paper | Special issue | Prepress
DOI: 10.3987/COM-19-S(F)6
■ Synthesis of Optically Active (R)- and (S)-β-Arginine from Pyroglutamic Acid

Yoko Yasuno, Akira Sawai, Ai Sekihara, and Tetsuro Shinada*

*Graduate School of Science, Osaka City University, 3-3-138, Sugimoto, Sumiyoshi, Osaka 558-8585, Japan

Abstract

The first synthesis of optically active β-arginine was achieved starting from commercially available pyroglutamic acid. The new synthetic protocol is characterized by the use of nitrile as a carboxylic acid surrogate which could be transformed to the corresponding 2-acyl-1,3-bis(1,1-dimethylethyl)imidodi-carbonic acid ester (active amide) via Pt-catalyzed hydration under the mild conditions. The active amide was converted to β-arginine and Boc-β-Arg-Val-OMe in good yield.

FREE:Supporting Info. (1.7MB)PDF (659KB)

Published online: 20th June, 2019

Paper | Special issue | Prepress
DOI: 10.3987/COM-19-S(F)5
■ Synthesis of 1,3,4-Oxadiazoles as Selective T-Type Calcium Channel Inhibitors

Man Zhang, Bende Zou, Medha J. Gunaratna, Sahani Weerasekara, Zongbo Tong, Thi D. T. Nguyen, Serkan Koldas, William S. Cao, Conrado Pascual, Xinmin Simon Xie,* and Duy H. Hua*

*Department of Chemistry, Kansas State University, 1212 Mid Campus Drive, Manhattan, KS 66506, U.S.A.

Abstract

Neuropathic pain, epilepsy, insomnia, and tremor disorder may arrive from an increase of intracellular Ca2+ concentration through a dysfunction of T-type Ca2+ channels. Thus, T-type calcium channels could be a target in drug discovery for the treatments of neuropathic pain and epilepsy. From rational drug design approach, a group of 2,5-disubstituted 1,3,4-oxadiazole molecules was synthesized and their selective T-type channel inhibitions were evaluated. The synthetic strategy consists of a short sequence of three reactions: (i) condensation of thiosemicarbazide with acid chlorides; (ii) ring closing by 1,3-dibromo-5,5-dimethylhydantoin; and (iii) coupling with various acid chlorides. 5-Chloro-N-(5-phenyl-1,3,4-oxadiazol-2-yl)thiophene-2-carboxamide (11) was found to selectively inhibit T-type Ca2+ channel over Na+ and K+ channels in mouse dorsal root ganglion neurons and/or human embryonic kidney (HEK)-293 cells and to suppress seizure-induced death in mouse model. Consequently, compound 11 is a useful probe for investigation of physiologic and pathophysiologic roles of the T-channel, and provides a basis to develop a novel therapeutic to treat chronic neuropathic and inflammatory pains.

FREE:PDF (466KB)

Published online: 12th June, 2019

Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14094
■ Synthesis and Antimicrobial Evaluation of Some Novel Heterocycles as Antipyrine Derivatives

Khaled S. Mohamed* and Elsherbiny H. El-Sayed

*Engineering Chemistry Department, Higher Institute for Engineering and Technology, New Damietta, New Damietta 34518, Egypt

Abstract

Novel antipyrine derivatives bearing pyran, pyridopyrimidine, chromene, benzothiazole, indole, pyrazole and pyridazine moieties were synthesized by using 2-cyano-N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)acetamide (1) as a staring material. The newly synthesized compounds were evaluated for their antimicrobial activities based on inhibition diameter zone against Gram-positive and Gram-negative bacteria.

FREE:PDF (531KB)

Published online: 11th June, 2019

Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14092
■ Divergent Synthesis of Indole-2-carboxylic Acid Derivatives via Ligand-free Copper-catalyzed Ullmann Coupling Reaction

Jiadi Zhou, Yongjian Chen, Junsong Huang, and Jianjun Li*

*Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, P. R. China

Abstract

This article describes a ligand-free copper-catalyzed Ullmann coupling reaction for the preparation of divergent indole-2-carboxylic acid derivatives including esters, amides and anhydrides. Various compounds 3, which could be synthesized from aldehydes conveniently, were used as substrate to provide the corresponding indole-2-carboxylic acid derivatives in moderate to good yields.

FREE:Supporting Info. (2.5MB)PDF (552KB)

Published online: 6th June, 2019

Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14072
■ Modified Dehydroellagitannins from Davidia involucrata Leaves

Akari Esumi, Hiroe Aoyama, Yuuki Shimozu, Shoko Taniguchi, and Tsutomu Hatano*

*Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushima-naka, Okayama 700-8530, Japan

Abstract

Davidia involucrata (Nyssaceae) is a naturally rare plant found in southern China. We isolated two previously undescribed ellagitannins, davicratinic acid B (5) and C (6), in addition to four known compounds, davicratinic acid A (1), helioscopinin B (2), granatin A (3), and pedunculagin (4). Spectral analyses revealed that compounds 5 and 6 are modified dehydroellagitannins with isomeric structures.

FREE:PDF (298KB)

Published online: 5th June, 2019

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14081
■ Secalonic Acids J–M, Four New Secondary Metabolites from the Marine-derived Fungus Penicillium oxalicum

Li Chen, Zhi-Hao Lu, Qin-Ying Liu,* Qiu-Hong Zheng, Lin Du, and Qi-Qing Zhang*

*Fujian Provincial Key Laboratory of Tumor Biotherapy, Fujian Cancer Hospital & Fujian Medical University Cancer Hospital, Fuzhou 350014, P. R. China

Abstract

Four new secalonic acid derivatives, secalonic acids J–M (1–4), were isolated from the marine-derived fungus Penicillum oxalicum. The planar structures of these compounds were elucidated by NMR and high-resolution mass spectrometric analyses. The absolute configurations were established by comparison of their experimental and calculated electronic circular dichroism spectra. Finally, these compounds were further evaluated for cytotoxic activities against the selected cancer cell lines in vitro. The results of flow cytometry demonstrated that compound 1 owned moderate activity of inducing apoptosis against HeLa cell.

FREE:PDF (1.3MB)

Published online: 3rd June, 2019

Communication | Special issue | Prepress
DOI: 10.3987/COM-19-S(F)7
■ A Novel Condensed Heterocyclic Quinone with a Dibezofuranobisthiadiazole Skeleton

Kazuma Sugawara, Wataru Nojo, Yusuke Ishigaki, Junko Ohkanda, and Takanori Suzuki*

*Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan

Abstract

Upon oxidation of hydroquinone fused with 1,2,5-thiadiazole by using FeCl3, a novel dibenzofurano[1,2-c:6,7-c']bis[1,2,5]thiadiazole-type quinone was obtained whereas the similar dimerization-condensation process did not occur for the pyrazine-fused hydroquinone under the similar conditions.

FREE:Supporting Info. (230KB)PDF (1.1MB)

Published online: 3rd June, 2019

Short Paper | Special issue | Prepress
DOI: 10.3987/COM-19-S(F)11
■ Isolation of Inohanalactone, a γ-Butyrolactone, from Nocardia inohanensis IFM0092T

Natsumi Kobayashi, Yasumasa Hara, Midori A. Arai, Shoko Hara, Tohru Gonoi, Takashi Yaguchi, and Masami Ishibashi*

*Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan

Abstract

Because research on the genus Nocardia has not progressed as compared to the extensively studied genus Streptomyces, Nocardia is considered as a useful undeveloped resource for exploring natural products. In this study, a new γ-butyrolactone derivative, named inohanalactone (1), was isolated from Nocardia inohanensis IFM0092T. Inohanalactone possesses an aliphatic side chain containing 8 carbons, a vicinal diol, and a cis double bond. Inohanalactone was produced by N. inohanensis IFM0092T in the modified Czapek–Dox medium, whereas it was not produced in other media such as Nutrient broth, Waksman, and Yeast-Malt-Glucose media.

FREE:Supporting Info. (1.6MB)PDF (341KB)

Published online: 10th April, 2019

Communication | Special issue | Prepress
DOI: 10.3987/COM-19-S(F)2
■ An Efficient Enantiospecific Synthesis of Neuroactive Glutamate Analogs

Shuntaro Tsukamoto, Hiyori Itagaki, Kenji Morokuma, Kei Miyako, Yuichi Ishikawa, Ryuichi Sakai, and Masato Oikawa*

*Yokohama City University, Seto 22-2, Kanazawa-ku, Yokohama 236-0027, Japan

Abstract

Herein we report improved enantiospecific synthesis and some structure-activity relationships of our heterotricyclic artificial glutamate analogs bearing seven-membered ring for the C-ring. Starting from readily available oxanorbornene rac-3, optically pure (2R)-TKM-107, (2R)-IKM-154, and the antipodes were synthesized in total nine steps for each. Mice in vivo assay indicated that only the (2R)-enantiomer was active in both cases. Behaviors phenotypes observed in the mice assay suggested that these compounds are similar in mode of action to that of IKM-159 but with discrete potency.

FREE:Supporting Info. (2.1MB)PDF (574KB)

Published online: 10th April, 2019

Paper | Special issue | Prepress
DOI: 10.3987/COM-19-S(F)3
■ Planar Chiral Phosphino[2.2]paracyclophanol-Catalyzed Highly Regio- and Stereoselective [3+2] Annulation Reaction of Morita–Baylis–Hillman Carbonates with Dicyanomethylideneoxindoles

Shinji Kitagaki,* Mayuka Tsuji, Hideki Teramoto, Naoko Takenaga, and Keisuke Yoshida

*Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan

Abstract

To demonstrate the utility of [2.2]paracyclophane as a chiral organocatalyst backbone, we examined a planar chiral pseudo-ortho-diarylphosphino[2.2]paracyclophanol, phosphino-PCP-ol, which has a spacer aryl group between the pseudo-ortho-substituted PCP-ol backbone and the diarylphosphino group. We tested this catalyst in the [3+2] annulation reaction of Morita–Baylis–Hillman carbonates, derived from aromatic aldehydes and methyl acrylate, with 3-(dicyanomethylidene)-2-oxindole. The catalyst produced the desired 3-spirocyclopentene-2-oxindoles in high yields, and high regio-, diastereo-, and enantioselectivities.

FREE:Supporting Info. (7.1MB)PDF (503KB)

Published online: 12th March, 2019

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14033
■ Synthesis of 1,2-Benzothiazole-3(2H)-thione 1,1-Dioxides by DBU-Promoted Cyclization of 2-(Aminosulfonyl)-N-methylbenzothioamide Derivatives

Kazuhiro Kobayashi* and Daiki Fujiwara

*Applied Chemistry Field, Chemistry and Biotechnology Course, Department of Engineering, Graduate School of Sustainability Science, Tottori University, 4-101 Koyama-minami, Tottori 680-8552, Japan

Abstract

An efficient method for the preparation of 2-alkyl-1,2-benzothiazole-3(2H)-thione 1,1-dioxides has been developed. Thus, the reaction of 2,N-dilithio derivatives of N-alkylbenzenesulfonamides with methyl isothiocyanate affords 2-[(alkylamino)sulfonyl]-N-methylbenzothioamides, which are treated with a catalytic amount of DBU in refluxing toluene to provide the desired products in moderate to good yields.

FREE:PDF (209KB)
16 data found. 1 - 16 listed