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18 data found. 1 - 18 listed

Published online: 2nd April, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14247
Design, Synthesis and in Vitro Antifungal Evaluation of Novel Triazole Derivatives

Guoqing Sui,* Li Ren, Ruiyuan Liu, Dan Xu, Hongdong Hao,* and Wenming Zhou*

*College of Chemistry & Pharmacy, Northwest A & F University, No. 22 Xinong Road, Yangling, Shaanxi Province 712100, China

Abstract

As a part of our continuing research on triazole derivatives antifungal agents, 10 novel target compounds containing 1,2,4-triazole moiety were synthesized and characterized by the spectroscopic analysis, and their in vitro antifungal activities against four phytopathogenic fungi were assayed systematically. Especially, compound 3c displayed excellent activity against F. graminearum with the median effective concentration value (EC50) of 5.03 µg/mL, and the value was extremely close to that of tebuconazole (EC50 = 3.13 μg/mL). Generally, for carbonyl compounds containing morpholine moiety, introducing 4-F to benzene ring obviously improved activities against most of tested fungi in varying degree.

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Published online: 1st April, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14243
Regioselective Synthesis of Quinoxaline-2-one Derivatives Regulated by Acid and Base

Wanli Liu, Qifeng Su, Kang Qiu, Meng Wang,* and Qun Lu*

*School of Life Science and Engineering, Southwest Jiaotong University, NO.111, North Second Ring Road Chengdu 610031, Sichuan, China

Abstract

A concise approach for the synthesis of quinoxalin-2-one derivatives through substituted o-phenylenediamines and α-ketoester with high regioselectivity is developed. Interestingly, the two regioisomers can be selectively obtained and the regioselectivity can be regulated by acid and base. The typical regioisomer ratio is up to 15:1 in acidic conditions and it can be easily reversed as 1:4 in basic conditions.

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Published online: 31st March, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14234
Copper-catalyzed β-Iodovinylation of Azoles and Pyrrole Derivatives

Simon Ricard, François Ladouceur, Guillaume Couture, and Benoit Daoust*

*Department of Chemistry, Biochemistry and Physics, University of Quebec in Trois-Rivieres, CP. 500, Trois-Rivieres, Quebec, Canada

Abstract

Herein is described an efficient copper-catalyzed synthesis of β-iodovinyl-azole and β-iodovinyl-pyrrole derivatives using (E)-1,2-diiodoethene which was efficiently applied to azole and pyrrole derivatives in both organic and hydro-organic medium to afford the corresponding β-iodovinylated adducts in up to excellent yields with complete stereocontrol. These nitrogenated vinyl iodides can be further functionalized into disubstituted olefins through various metal catalyzed coupling reactions.

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Published online: 27th March, 2020

Review | Regular issue | Prepress
DOI: 10.3987/REV-20-926
The Synthesis of Heterocyclic Compounds Based on 3-Formylchromone via Organic Reactions

Ghodsi Mohammadi Ziarani,* Parisa Mofatehnia, Fatemeh Mohajer, and Razieh Moradi

*Department of Chemistry, Alzahra University, Vanak Square, Tehran, P.O. Box 1993891176, Iran

Abstract

3-Formylchromones are known as key heterocyclic scaffolds for the synthesis of various important organic compounds. The compounds with 3-formylchromone have attracted much attention among heterocyclic structures. This review article aims to provide an overview of multi-component reactions related to 3-formylchromone derivatives in the synthesis of various heterocyclic compounds covering the literature going back to 2015 until 2019.

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Published online: 25th March, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14231
Synthesis of Methylophiopogonanone A

Ryo Katagiri, Uekusa Yoshinori, Yuji Narukawa, and Fumiyuki Kiuchi*

*Faculty of Pharmacy, Keio University, 1-5-30 Shiba-Kouen, Minato-ku, Tokyo, Japan

Abstract

Ophiopogon Root (root of Ophiopogon japonicus Ker-Gawler, Liliaceae) is a crude drug used as expectorant, anti-cough and tonic in Kampo medicine (traditional Japanese medicine) as well as other traditional medicines of Asian countries. It contains characteristic homoisoflavonoids with methylated ring A. We synthesized methylophiopogonanone A (1), which is a candidate marker compound for identification test of Ophiopogon Root, from phloroglucinol in 9 steps with overall yield of 11.1%

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Published online: 24th March, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14228
Identification and Quantification of Alkaloid Compounds from Different Parts and Production Areas of Datura metel L.

Yang Shi Hui, Liu Yan, Wang Qi, Sun Yan Ping, Guan Wei, Liu Yuan, Yang Bing You,* and Kuang Hai Xue*

*Key Laboratory of Chinese Materia, Heilongjiang University of Chinese Medicine, Ministry of Education, Harbin 150040, China

Abstract

An ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) method was used to identify alkaloids in six parts of Datura metel L. (D. metel L.). 65 Alkaloids were tentatively identified. Meanwhile, a rapid, sensitive and reliable ultra-high-performance liquid chromatography tandem triple quadrupole mass spectrometry (UPLC-Q-TRAP-MS/MS) technique had developed to determine the contents of 22 alkaloids in five minutes, with good precision and repeatability. This method provided a feasible solution for the content determination of alkaloid in D. metel L.

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Published online: 23rd March, 2020

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14229
Antifungal Compound against Azole-Resistant Candida albicans from a Marine-Derived Fungus, Paraboeremia selaginellae

Eri Yamaguchi, Kazuha Okabe, Hitoshi Kamauchi, Sanae Kurakado, Takashi Sugita, Kaoru Kinoshita,* and Kiyotaka Koyama*

*Department of Pharmacognosy and Phytochemistry, Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588, Japan

Abstract

A new compound (1) and AB4063-A (2), whose stereochemistry was unstated, were isolated from the marine-derived fungus Paraboeremia selaginellae. The structure of 1 was elucidated from spectroscopic data (NMR, MS, IR), and the absolute configuration of the N-methylvaline moiety was determined. Compound 2 showed antifungal activity against azole-resistant Candida albicans.

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Published online: 19th March, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14236
The Synthesis and Glycosidase Inhibitory Activity of Analogues of Tiruchanduramine

Zackary J. R. Ashworth, Barbara Bartholomew, Daniel M. Evans, Josephine Forde-Thomas, Karl F. Hoffmann, Reece Murdoch, Robert J. Nash, Hazel Sharp, Helen Whiteland, and Patrick J. Murphy*

*School of Natural Sciences, Bangor University, Gwynedd, LL57 2UW, UK

Abstract

Five analogues (7a-e) of the metabolite tiruchanduramine 1 were prepared. Compounds 7d and 7e were specific inhibitors of yeast α-glucosidase, whilst 7e specifically inhibited Bacillus α-glucosidase. Compounds 7b and 7c were the best inhibitors of β-glucosidase. All 5 compounds inhibited β-galactosidase, but once again 7e was the best inhibitor. It was apparent that different chain lengths in the compounds 7a-e affect the degree of inhibition. Some of the synthetic analogues show significantly improved inhibition of α-glucosidases when compared to tiruchanduramine 1 and also improved specificity.

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Published online: 17th March, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14232
Lactamization of Alkenyl C-H Bonds to Generate 2-Quinolinones with Triphosgene

Zhen Zhang,* Zixiao Wang, and Guizhi Du*

*Key Laboratory of Coarse Cereal Processing (Ministry of Agriculture and Rural Affairs), Chengdu University, Chengluo Road 2025, Chengdu, Sichuan 610041, China

Abstract

A simple and easy-going method is developed to synthesize the analogues of 2-quinolinones by using triphosgene (BTC) as the carbonyl source. In these reactions, both the toxic carbon monoxide (CO) and phosgene are avoided and the 2-quinolinones are obtained in moderate to good yields under mild conditions, all of which are anticipated to be meaningful in both industry and laboratory.

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Published online: 11th March, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14223
Absolute Configuration of the Butenolide of Abietane

Min Li, Xu Li, Ian D. Williams, Herman H-Y. Sung, Zhi-Da Min, and Qiong Zhang*

*Department of Pharmaceutical Science, Shanxi Medical University, 56 Xinjian South Road, Taiyuan, Shanxi Province 030001, China

Abstract

17-Hydroxyjolkinolide A-B (1-2) and jolkinolide A-B (3-4) are four ent-13(15)-abietane-16,12-olide type diterpenoids isolated from the roots of Euphorbia fischeriana Steud. The absolute configurations of 1 and 2 were established by X-ray crystallographic analysis of their mono-bromobenzoate derivatives. On basis of our research, the absolute configuration of the butenolide of abietane can be determined by ECD spectra. The potential antituberculosis effects of these diterpenoids were evaluated using a Mycobacterium smegmatis model. The most potent compound according to the in vitro bioassay used was 17-hydroxyjolkinolide B (2) (MIC 1.8 μg/mL).

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Published online: 10th March, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14230
Ag(I)/sec-Amine-Amidphos-Catalyzed endo-Stereoselective Synthesis of Fully Substituted Pyrrolidines via 1,3-Dipolar Cycloaddition Based on Azomethine Ylides

Haifei Wang, Chen Zhang, Jialin Liu, Xinluo Song, and Haiyun Jiang*

*College of Packaging and Materials Engineering, Hunan University of Technology, Zhuzhou 412007, China

Abstract

Cooperative catalysis using multifunctional organic scaffolds in combination with transition-metal ions is emerging as a powerful tool in asymmetric synthesis. In this report, a series of multifunctional amidophosphanes derived from substituted 1,2-benzenediamine or 2-aminobenzylamine and chiral α-amino acids, in combination with silver(I) salts, have been developed to cooperatively catalyze the azomethine ylides-involved 1,3-dipolar cycloaddition with maleates. Under optimal conditions, fully substituted endo-pyrrolidines were obtained in high to excellent yields (up to 92% yield) and enantioselectivities (up to 94% ee).

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Published online: 5th March, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14201
Bis(1,3-dimethylimidazolidinone) Hydrotribromide (DITB) Promoted Multicomponent Reaction for the Synthesis of Highly Functionalized Piperidines

Shiqiang Yan, Shuwang He, Shuying Li, Zhiqiang Hu,* and Wei Zhang*

*School of Pharmacy, Fudan University, Shanghai 201203, China

Abstract

A convenient and efficient method has been developed for the synthesis of highly functionalized piperidines via three-component, one-pot domino reaction of β-ketoesters, aromatic aldehydes, and anilines in the presence of catalytic amount of bis(1,3-dimethylimidazolidinone) hydrotribromide (DITB) in ethanol at room temperature.

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Published online: 4th March, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14235
Novel Ring Transformation of Uracils to 2-Oxazolidinones

Yoshiaki Kitamura,* Yuki Nagaya, Yuto Ohshima, Daiki Kato, Asuki Ohguchi, Hiroshi Katagiri, Masato Ikeda, and Yukio Kitade

*Department of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University , 1-1 Yanagido, Gifu, Gifu 501-1193, Japan

Abstract

Treatment of N3-electron-withdrawing group-protected uracil derivatives bearing a 2-hydroxyethyl moiety at the 1-position with base under anhydrous conditions affords the corresponding 2-oxazolidinone by opening the pyrimidine ring between C2 and N3, followed by ring closure between C2 and the neighbouring hydroxy group. This ring transformation is applicable to various uracil analogues to obtain the desired 2-oxazolidinone in moderate to excellent yield.

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Published online: 2nd March, 2020

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14213
Synthesis and Fluorescence of 9-Benzyl-9H-carbazole Derivatives and Its Application for Recognition of Rare Earth Cations

Yu-Ying Du, Li-Min Han,* Liang-Wu Guo, Zhi-Chao She, Jing Cui, Li Lv, and Ruo-Xuan Gao

*Department of Chemical Engineering, Inner Mongolia University of Technology, Huhhot 010051, PR China

Abstract

The synthesis and photophysical properties of 9-benzyl-9H-carbazole derivatives have been investigated. A novel ethyl 9-benzyl-1-methyl-9H-carbazole-2-carboxylate (Bncz 1) fluorescent chemosensor has been developed to recognize Ce(III) through a significant increase in fluorescence intensity in ethanol, whereas there is minimal difference on the introduction of the other rare earth metal cations (Yb3+, Sm3+, Gd3+, Er3+, Pr3+, Eu3+, Tb3+, Tm3+, Dy3+, Ho3+, Nd3+, Lu3+, Y3+, Sc3+, La3+). A moderate association constant of K= 2.419 × 105 L·mol−1 has been determined by fluorescence titration, and the corresponding Jobs plot analysis indicated 1:1 binding for metal complex formation. The linear increase in fluorescence intensity in response to different concentrations of Ce3+ gives a low limit of detection of 7.269 × 10-6 M. 9-Benzyl-9H-carbazole derivative probe has a great potential for the detection of rare earth metal cations.

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Published online: 7th February, 2020

Review | Regular issue | Prepress
DOI: 10.3987/REV-19-925
Survey of Briarane-Type Diterpenoids – Part VII

Yu-Hsin Chen, Hsien-Kuo Chin, Bo-Rong Peng, You-Ying Chen, Chiung-Chin Hu, Li-Guo Zheng, Thanh-Hao Huynh, Tung-Pin Su, Yi-Lin Zhang, Zhi-Hong Wen, Tsong-Long Hwang,* Yang-Chang Wu,* and Ping-Jyun Sung*

*National Museum of Marine Biology and Aquarium, Pingtung 94450, Taiwan

Abstract

The structures, names, bioactivities, and references of 78 briarane-type natural products, including 56 new metabolites, isolated between 2017 and 2019 are summarized in this review article. All the briarane diterpenoids mentioned in this review were isolated from the octocorals Alcyonacea belonging to genus Briareum; the Gorgonacea belonging to genus Junceella and Subergorgia; and the Pennatulacea belonging to genus Anthoptilum. Some of these compounds exhibited potentially biomedical activities, including anti- inflammatory activity, antiviral activity, and cytotoxicity.

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Published online: 22nd January, 2020

Review | Regular issue | Prepress
DOI: 10.3987/REV-19-922
Bridged Nucleosides as Building Blocks of Oligonucleotides: Synthesis and Properties

Yoshiyuki Hari*

*Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan

Abstract

Bridging between the 2ʹ- and 4ʹ-carbons in a nucleoside restricts the furanose ring to C3ʹ-endo conformation, which coincides with the sugar conformation in an oligonucleotide forming a duplex with single-stranded RNA (ssRNA) and a triplex with double-stranded DNA (dsDNA). Therefore, oligonucleotides modified by 2ʹ,4ʹ-bridged nucleosides generally increase hybridization ability with ssRNA and dsDNA when compared with the natural oligonucleotide. Till date, a large number of 2ʹ,4ʹ-bridged nucleosides with additional two-atom to four-atom bridges between 2ʹ- and 4ʹ-carbons have been developed by many research groups including our group. For this, ionic cyclization, ring-closing metathesis, and radical cyclization have been used so far as the synthetic strategies of bridge constructions. Based on such a background, we recently proposed a 2ʹ,4ʹ-bridged nucleoside possessing 6ʹ-oxygen founded on a new design concept and several types of analogs including 2ʹ-O,4ʹ-C-ethyleneoxy-bridged 5-methyluridine with a four-atom bridge have been developed. In addition, as a new strategy of bridge construction, radical cyclization using the 4ʹ-carbon radical of a nucleoside was exemplified and a promising 2ʹ,4ʹ-bridged nucleoside, the 6ʹ-methyl analog of 2ʹ-O,4ʹ-C-ethylene-bridged 5-methyluridine, was found. This review mainly focuses on our recent results on bridged nucleosides used for chemically modified oligonucleotides. It describes the design and synthesis of the bridged nucleosides, along with the properties of oligonucleotides including bridged nucleosides.

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Published online: 10th January, 2020

Review | Regular issue | Prepress
DOI: 10.3987/REV-19-919
Alkyl Pyridinesulfonates and Allylic Pyridinecarboxylates, New Boosters for the Substitution at Secondary Carbons

Yuichi Kobayashi*

*Meiji University, Organization for the Strategic Coordination of Research and Intellectual Properties, 1-1-1, Higashimita, Tama-ku, Kawasaki, Kanagawa, 214-8571, Japan

Abstract

Substitution at allylic secondary carbons using the pyridinecarboxylate (picolinoxy, PyCO2, or Pic) leaving group is described in the first part of this review (Sections 2–4). Alkyl as well as less reactive alkenyl, heteroaryl, and aryl copper reagents are suitable for the substitution, giving anti SN2' products highly regio- and stereoselectively. In Section 2, finding and synthetic application of the allylic substitution giving tertiary carbon centers are presented. Extension of the substitution for the construction of quaternary carbon centers is described in Section 3 with its synthetic application. Section 4 deals with the construction of quaternary carbon centers on cyclohexane rings by the allylic substitution of cyclohexylidene picolinates. The stereochemistry is created by equatorial attack to the chair conformer with high diastereselectivity. The stereochemical prediction facilitated synthesis designs of biologically active compounds. The second part of the review (Section 5) presents recent advances in metal-catalyzed substitutions at secondary alkyl carbons, giving enantiomerically enriched products. Our findings of the pyridinesulfonyloxy leaving group and an associated copper catalyst are included. Substitutions with cuprates are mentioned briefly for reactivity discussion with the copper-catalyzed substitution.

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Published online:

Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14206
Transition Metal-free Cycloaddition of N-Boc-N-propargylenamines

Yuya Chikayuki, Yasuaki Kouno, Shiori Yonekawa, Haruka Ishikawa, Yoko Waki, Hiroyoshi Teramoto, Shigeru Sasaki, Kimio Higashiyama, and Takayasu Yamauchi*

*Institute of Medicinal Chemistry, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan

Abstract

An efficient method for the synthesis of multi-substituted pyrroles was developed using basic cyclization of readily accessible N-Boc-N-propargylenamines. Despite the basic conditions, cleavage of the N-Boc group occurred easily. The process was rapid and afforded N-H-pyrroles with wide functional group tolerance in high yields.

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18 data found. 1 - 18 listed