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15 data found. 1 - 15 listed

Published online: 19th February, 2020

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14209
A Facile Synthesis and Antibacterial Activity of Novel Quinoxaline-Benzofuran Hybrids

Yang Li, Bingyue Tang, Shiyu Dong, Hongwei Qin, Wentao Gao,* and Yu Chen*

*Institute of Superfine Chemicals, School of Chemistry and Chemical Engineering, Bohai University, 19 Keji Road, Jinzhou 121000, China

Abstract

In the present work, a simple and facile synthesis of a series of new type of quinoxaline-benzofuran hybrids, i.e., 3-(benzofuran-2-yl)quinoxaline- 2-carboxylic acids has been achieved using the newly-synthesized ethyl 3-bromomethylquinoxaline-2-carboxylate as substrate through ultrasound-assisted one-pot sequential Rap-Stoermer type reaction with various salicylaldehydes followed by ester hydrolysis. A preliminary screening for their antibacterial activities against five bacterial strains revealed that compounds with tert-butyl and halo (Cl and Br) substituents exhibited promising inhibitory activity against B. subtilis with the MIC values of 15.625 and 7.8125 μg/mL, respectively, being equipotent or even better than the reference Ciprofoxacin.

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Published online: 19th February, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14221
New Schiff Bases Based on 1-Aminopyrimidine-2-(1H)-one: Design, Synthesis, Characterization and Theoretical Calculations

Zülbiye Kökbudak, Halime Güzin Aslan, and Senem Akkoç*

*Department of Pharmacy, Süleyman Demirel University, Suleyman Demirel University, Turkey

Abstract

In this study, 1-amino-5-benzoyl-4-phenylpyrimidin-2(1H)-one (1) was synthesized from 4-benzoyl-5-phenylfuran-2,3-dione and 1-(1-phenylethylidene)semicarbazide in benzene. Since pyrimidine-based Schiff bases have an extensive working range, two new compounds (2, 3) were synthesized from the reaction of this starting material (1) with 3-bromobenzaldehyde or 4-chlorobenzaldehyde. The structures of the synthesized new compounds were clarified employing FT-IR, 1H NMR, 13C NMR, and elemental analysis. HOMO, LUMO, and energy gap between them was calculated as theoretical. On the other hand, conformation analysis studies of compounds were carried out for determining the energies of the conformers.

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Published online: 17th February, 2020

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14222
Synthesis and Cytotoxic Activity of Some New Bipyrazole Derivatives

Bader A. Salameh,* Kayed A. Abu-Safieh,* Islam S. AL-Aqrabawi, Fatima Alsoubani, and Lubna H. Tahtamouni

*Department of Chemistry, Faculty of Science, Hashemite University, P.O. Box 330127 Zarqa, 13133, Jordan

Abstract

A new series of bipyrazole derivatives were prepared and characterized via the reaction of 5-hydrazino-1,3-dimethyl-4-nitro-1H-pyrazole with various 1,3-dicarbonyl compounds. The synthetic pathway was based on the classical Knorr pyrazole synthesis. In vitro cytotoxic activity of the fully characterized bipyrazole derivatives was determined and their IC50 values were also reported.

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Published online: 14th February, 2020

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14215
New and Convergent Synthesis of AZD4547

Lehao Bu, Han Wang,* Wenxin Chen, Lei Gao, Cong Sun, and Yongjun Mao

*College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, 333 Longteng Rd., Songjiang, Shanghai, 201620, China

Abstract

A practical and convergent synthetic route of AZD 4547 was developed successfully. The intermediate 5-(3,5-dimethoxyphenylethyl)-1H- pyrazol-3-amine (7) was prepared from 3,5-dimethoxybenzaldehyde through 6 simple steps in 52.3% yield. Another intermediate 4-((3S,5R)-3,5- dimethylpiperazin-1-yl)benzoic acid (14) was synthesized from ethyl 4-fluorobenzoate and (2R,6S)-2,6-dimethylpiperazine in 62% yield over 2 steps. Finally, AZD 4547 was obtained from 7 and 14 in 73% yield and 99.1% purity. Purification methods of the intermediates and the final product involved in the route were developed.

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Published online: 14th February, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-20-14219
Concise Synthesis and Evaluation of Ortho-Naphthoquinones Containing A Phenolic Hydroxy Moiety

Mitsuaki Yamashita, Syuhei Hata, Jun Sawano, Ryuji Umeda, and Akira Iida*

*School of Agriculture, Kindai University, Nakamachi, Nara 631-8505, Japan

Abstract

A concise and efficient synthesis method for the preparation of anti-proliferative ortho-naphthoquinones is described. Notably, the synthesis of ortho-furanonaphthoquinone was achieved by utilizing a regioselective oxidative conjugate addition of dimethylamine and the Sonogashira coupling/cyclization reaction as the key steps. Additionally, an improved synthesis of hydroxy-β-lapachone was established and included a regioselective prenylation by directed ortho-lithiation. In vitro antiproliferative effects of the synthesized analogs against a panel of 39 human cancer cell lines were evaluated and the results were directly compared to those previously obtained for 1.

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Published online: 12th February, 2020

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14173
Microwave-Assisted Synthesis of Lycoperdic Acid via The 1,3-Dipolar Cycloaddition of Methylene Dimethyl Glutarate and Nitrone Derived (-) Menthone

Abigail Kempf, Jaffarguriqbal Singh, Dina C. Merrer, and Richard Washington Denton*

*Chemistry And Environmental Science, Medgar Evers College- CUNY, 142- Home Street, Valley Stream, NY 11580

Abstract

The 1,3-dipolar cycloaddition reaction of dimethyl2-methylene- glutarate and (-)-menthone-derived nitrone occurred with moderate selectively to produce the desired isoxazolidine which was a direct precursor to the (2S,4S)-substituted glutamate derivative in an overall yield of 20%. The possibility of preparing the unnatural amino acid, (S)-(+)-lycoperdic acid was studied based on its evidence within the mass spectra of the final product.

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Published online: 7th February, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14195
Preparation and cytotoxic evaluation of vouacapane oxidation products

Armando Talavera-Alemán, Mario A. Gómez-Hurtado, Gabriela Rodríguez-García, Alejandra Ochoa-Zarzosa, Christine Thomassigny, Cerda-Garcia-Rojas M. Carlos,* Pedro Joseph-Nathan, and Rosa E. del Río*

*Department of Chemistry, CINVESTAV-IPN, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, C.P. 07000, Mexico, D.F., Mexico

Abstract

Treatment of (−)-(5S,6R,8S,9S,10R,14R)-6-acetoxyvouacapane (1) with DDQ, mCPBA, or Cr(VI) reagents afforded diterpenoids with various degrees of oxidation at the furan and C rings. Oxidation of 1 using DDQ provided the known benzofuran 2, together with the new derivatives dimer 3, lactone 4, and aldehyde 5, while mCPBA oxidation gave 2, spirocassenolide 6, and cassenolides 7 and 8a. Oxidation of 1 with CrO3 gave 4, 6, 8a, and spirocassenolide 9, while the use of K2Cr2O7 yielded 4, 9, and spirocassenolide 10. The structures of the new compounds followed from HRMS, NMR measurements, and by single-crystal X-ray diffraction of 3, 4, 8b, and 10. Compounds 1, 2, and 6 were evaluated for their cytotoxic activity against the MCF-7 and HL-60 cancer cells, showing moderate cytotoxic activity.

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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: 4th February, 2020

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14198
Three New Furan-2-Carboxylic Acid Derivatives from The Stem Bark of Nicotiana Tabacum and Their Bioactivity

Yin-Ke Li, Na Lv, Dian Luo, Wei-Song Kong, Qi-Li Mi, Qian Gao, Wan-Li Zeng, Jing Li, Jun Ling, Chun-Bo Liu, Guang-Yu Yang, Xue-Mei Li, Zhang-Yu Chen,* and Qiu-Fen Hu*

*Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission & Ministry of Education, Yunnan Minzu University, Kunming 650031, China

Abstract

Three new (1-3), together with three known (4-6) furan-2-carboxylic acid derivatives were isolated from the stem bark of Nicotiana tabacum. Their structures were determined by means of HRESIMS and extensive 1D and 2D NMR spectroscopic studies. Compounds 1~6 were tested for their anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity. The results revealed that compounds 1-6 showed good inhibition with IZD of 12.8±2.3, 13.5±1.8, 14.3 ±2.2, 15.1 ±2.0, and 14.7±2.2 mm. Compounds 1-6 were also tested for the antioxidant activity, and they showed notable antioxidant activity with an IC50 value of 3.86, 4.05, 3.62, 4.11, 3.57, and 3.64 μg/mL, respectively.

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Published online: 30th January, 2020

Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14192
Natural Products for Biocides Discovery: Discovery of Arundine and It’s Derivatives as Novel Antiviral and Anti-phytopathogenic-Fungus Agents

Ancai Liao, Shengli Jin, Ziwen Wang,* and Qingmin Wang*

*Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education, College of Chemistry, Tianjin Normal University, No.393, Extension of Bin Shui West Road, Xi Qing District, Tianjin 300387, China

Abstract

Plant diseases are one of the natural disasters that seriously harm agricultural production, and it is very difficult to control. The discovery of new antiviral and antifungal lead compounds becomes more and more important. Natural product arundine was found to have anti-tobacco mosaic virus (TMV) activity and anti-phytopathogenic-fungus activity for the first time. A series of arundine analogues were designed, synthesized and evaluated for their antiviral and fungicidal activities. Compound 6 with excellent antiviral activity emerged as novel antiviral lead compound. Compound 7 with 12.6−38.3 μg/mL EC50 values against 14 plant pathogens emerged as novel antifungal lead compound. This work laid a foundation for promoting the application of arundine analogues in plant protection.

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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: 22nd January, 2020

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14191
Synthesis and Biological Evaluation of NMDI-14 Derivatives as anti-Mesothelioma Agents

Hong Nhung Nguyen, Koya Suzuki, Yasuaki Kimura, Takatsugu Hirokawa, Yuko Murakami-Tonami, and Hiroshi Abe*

*Graduate School of Sceince, Nagoya University, Furo, Chikusa, Nagoya, Aichi 464-8602, Japan

Abstract

Mesothelioma is a severe tumor formed in pleura and peritoneum, for which no useful molecular-targeting therapy is available. We synthesized several derivatives of NMDI14, which is a reported inhibitor for non-sense mediated mRNA decay, and evaluated the activity of the NMDI14 derivatives as potential anti-mesothelioma agents. Some of the synthesized compounds showed promising activity in terms of cytotoxicity toward mesothelioma model cells and promotion of GAS5 expression selectively in mesothelioma cells. These results indicate that the NMDI14 derivatives may be useful for further developing clinically effective anti-mesothelioma drugs.

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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: 8th January, 2020

Review | Regular issue | Prepress
DOI: 10.3987/REV-19-918
Synthesis of Heterocycles Utilizing N-Alkoxyimines and Amides

Motohiro Yasui, Norihiko Takeda, and Masafumi Ueda*

*Department of Medicinal Chemistry, Kobe Pharmaceutical University, 4-19-1, Motoyamakitamachi, Higashinada, Kobe 658-8558, Japan

Abstract

N-Alkoxyimines and amides are unique functional groups bearing adjacent N-O bonds. Alkynes having an N-alkoxyimine or amide group generate reactive vinyl metal species through activation by a transition metal catalyst to synthesize heterocycles. This approach, which allows various sequential reactions, can be expected to directly form a complex heterocycle from a simple starting material under mild conditions. Meanwhile, these kinds of reactions require chemoselectivity between the N- and O-atoms at the nucleophilic site and/or regioselectivity at the electrophilic alkyne moiety. This review introduces intramolecular nucleophilic addition of N-alkoxyimines/amides into an alkyne moiety, followed by various transformations to synthesize heterocycles.

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Published online: 23rd December, 2019

Review | Regular issue | Prepress
DOI: 10.3987/REV-19-915
Chemistry of Anti-Hiv Active Trimeric Pyranonaphthoquinone Conocurvone: Synthetic Studies towards Monomeric Teretifolione B and Related Compounds

Takuya Kumamoto* and Kazuaki Katakawa

*Department of Synthetic Organic Chemistry, School of Pharmaceutical Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan

Abstract

Pyranonaphthoquinone natural products are widely distributed in plants and microorganisms and have diverse biological activities. Angular benzochromenes are a small class of natural products isolated from Conospermum and Pentas plants. Of these, conocurvone was isolated from Conospermum as a trimeric pyranonaphthoquinone that has potent anti-HIV activity. We have focused on the total synthesis of compounds that exhibit biological activity or whose activity is enhanced upon oligomerization. This review describes the discovery and biological activities of the trimeric pyranonaphthoquinone conocurvone and related compounds, as well as our and other researchers’ synthetic studies toward monomeric pyranonaphthoquinones.

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15 data found. 1 - 15 listed