Prepress

Regular Issues

24 data found. 1 - 24 listed

Published online: 17th May, 2021

Communication | Regular issue | Prepress
DOI: 10.3987/COM-21-14447
Debromooscillatoxins G and I from the Cyanobacterium Moorea Producens

Kanon Iguchi, Masayuki Satake, Yutaro Nishio, Bo-Tao Zhang, Kento Kawashima, Hajime Uchida, and Hiroshi Nagai*

*Department of Ocean Sciences, Tokyo University of Marine Science and Technology, Tokyo 108-8477, Japan

Abstract

Debromooscillatoxins G and I (1 and 3) were isolated from the marine cyanobacterium Moorea producens collected in Okinawa. Their structures were determined based on spectroscopic data, including nuclear magnetic resonance (NMR) and high resolution mass spectrometry (HRMS). Both the isolated compounds showed moderate cytotoxicity and diatom growth inhibition at a concentration of 10 µg/mL.

FREE:Supporting Info. (1.8MB)PDF (405KB)

Published online: 14th May, 2021

Paper | Regular issue | Prepress
DOI: 10.3987/COM-21-14456
Synthesis and Biological Activities of Selenium/Thioether Quinazoline Compounds

Canjun Yan, Yuchun Zhang, Guihan Zhao, Xiaohong Jin, Wuwei Yang, Pengpeng Niu, Haojie Wang, and Gang Liu*

*School of Chemistry and Materials Science, Ludong University, Yantai 264025 China

Abstract

In view of the important role of quinazoline skeletons in anti-cancer drugs like Gefitinib and the vital importance of organoselenium compounds in biomedicine field, in this protocol, twenty quinazoline selenium derivatives were designed and synthesized with the aim to develop new anti-cancer drugs by utilizing the synergistic effects of quinazoline skeleton and selenium. In addition, the synthetic method of thioether substituted quinazolines was improved. The biological activities of title compounds were determined against A549 cancer cells in vitro by using MTT assay at 1 μM and 10 μM concentrations. The results showed that most of the title compounds had good anticancer activities. Of note, 6-chloro-4-benzylselenoquinazoline (G5) exhibited better inhibitory activity (67.8% inhibition ratio) than the positive control drug Gefitinib (62.9% inhibition ratio) at the concentration of 10 μM. These findings will provide some clues for further research of anticancer drugs.

FREE:Supporting Info. (1.1MB)PDF (1.4MB)

Published online: 14th May, 2021

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-21-14480
Total Synthesis of Hyalodendriol C

Ishtiaq Jeelani,* Katsunori Itaya, and Hitoshi Abe

*Graduate School of Innovative Life Science, University of Toyama, 3190 Gofuku 930-8555, Japan

Abstract

We present a total synthesis of hyalodendriol C, a fungal natural product. We have focused on the use of palladium-catalyzed intramolecular biaryl coupling reaction of phenyl benzoate derivatives to synthesize hyalodendriol C. Keeping in view, the indispensable biological values of this compound, we took the advantage of our established strategy to chemically synthesize hyalodendriol C. The total synthesis of hyalodendriol C got accomplished in 10 steps beginning with the preparation of phenol derivative from the commercially available 5-methylbenzene-1,3-diol and synthesis of the corresponding benzoic acid derivative.

FREE:Supporting Info. (962KB)PDF (1.1MB)

Published online: 10th May, 2021

Review | Regular issue | Prepress
DOI: 10.3987/REV-21-956
Synthetic Approaches toward Certain Structurally Related Antimicrobial Thiazole Derivatives (2010-2020)

Abdelfattah Hassan, Heba A. Hassan, Dalia Abdelhamid, and Gamal El-Din A. Abuo-Rahma*

*Medicinal Chemistry Department, Faculty of Pharmacy, Minia University, Minia, Egypt & Pharmaceutical Chemistry Department, Faculty of Pharmacy, Deraya University, New Minia, Minia, Egypt

Abstract

In the present literature review, we comprehensively discuss different methods of synthesis of published antimicrobial thiazole derivatives in the last decade mainly those which showed antibacterial, antimycobacterial and/or antifungal activity. Owing to the great diversity of thiazole-derived antimicrobial agents, we organized most of them chemically in stipulated classes. In each class, we mentioned common methods of thiazole ring closure and indicated antimicrobial activity of the most active derivatives in clear and simple way.

FREE:PDF (2.1MB)

Published online: 28th April, 2021

Review | Regular issue | Prepress
DOI: 10.3987/REV-20-953
Recent Achievements in the Synthesis of Heterocyclic Compounds by Phthalhydrazide-Based Multicomponent Reactions

Ghodsi Mohammadi Ziarani,* Negar Jamasbi, and Fatemeh Mohajer

*Department of Chemistry, Faculty of Physic and Chemistry, Alzahra University, Tehran, Iran. P. O. Box 1993893973

Abstract

Phthalhydrazide is one of the useful starting material toward the synthesis of heterocyclic compounds, and considered as a valuable structural unit in organic synthesis due to its significant pharmacological and biological activities. There are many multicomponent reactions using phthalhydrazide under different conditions. This review article aims to give an overview of recent applications of phthalhydrazide in the multicomponent reactions during the period of 2006 to 2021.

FREE:PDF (2.4MB)

Published online: 20th April, 2021

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-21-14446
Recyclable Heterogeneous Nanocrystal Promoted Cascade Reaction in Water: An Access to Green Synthesis of Highly Functionalized 4H-pyrans Containing Phosphonate Motif

Yong-Hong Cai, Ya-Sa Xie, Ran Li, Ming-Mei Fan, Jing-Jing Li, Chuan-Bao Zhang,* and Jin-Fang Yuan*

*College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China.

Abstract

A green and environmentally friendly cascade reaction of diethyl (2-phenylacetyl)phosphonate with benzylidenemalononitrile promoted by Zr-Ce-SBA-15-NH2 in water was developed, and a wide range of highly functionalized 4H-pyrans containing phosphonate motif were obtained in up to 89% yield. Moreover, SBA-15-NH2 also showed good catalytic activity for this transformation in acetonitrile.

FREE:Supporting Info. (1.5MB)PDF (1.1MB)

Published online: 15th April, 2021

Review | Regular issue | Prepress
DOI: 10.3987/REV-21-958
Recent Advances in 1,2,4-Triazole Ring Construction via Cycloaddition Reactions

Nataliya Korol,* Mikhailo Slivka, and Oksana Holovko-Kamoshenkova

*Organic synthesis laboratory, Faculty of Chemistry, Uzhhorod National University, Uzhhorod 88000, Ukraine

Abstract

The sources, describing cycloaddition reactions that lead to obtaining of substituted 1,2,4-triazoles and their fused derivatives were reviewed. The review article covers the literature data published in the period 2011-2021. Synthetic particularities of cycloaddition products, the optimization of reaction conditions, factors that influence on the direction of the reaction are reasonably mentioned. Cycloaddition reactions are presented as convenient method for obtaining of as functional 1,2,4-triazoles, as well as their fused derivatives.

FREE:PDF (867KB)

Published online: 14th April, 2021

Paper | Regular issue | Prepress
DOI: 10.3987/COM-21-14460
Metal-Free sp3 C-H Bond Oxidation and Functionalization of α-Bromoketones to Quinoxalinone, Benzoxazinone, and Benzothiazinone Heterocyclic Compounds

Tianlong Wei, Haiying Tian, Fang Guo,* Hongxue Qi, and Xiuling Chen*

*School of Nuclear Technology and Chemistry & Biology, Hubei University of Science and Technology, Xianning 437100, China

Abstract

A series of heterocyclic compounds (benzothiazinones, benzoxazinones and quinoxalinones) were efficiently synthesized in excellent yields via α-bromoketones with o-substituted aniline (2-aminothiophenol, aryl-1,2-diamines and 2-aminophenol). This protocol accomplishes sp3 C-H bond oxidation and functionalization in one-pot without any metal catalyst.

FREE:Supporting Info. (1.3MB)PDF (581KB)

Published online: 12th April, 2021

Review | Regular issue | Prepress
DOI: 10.3987/REV-20-950
Iodine-Containing 4,7-Dihalobenzo[b]thiophene Building Blocks and Related Iodobenzo[b]thiophenes: Promising Molecular Scaffolds for Bio-Inspired Molecular Architecture

Kozo Toyota* and Shinichi Mikami

*Department of Chemistry, Graduate School of Science, Tohoku University, Aoba, Sendai, Miyagi 980-8578, Japan

Abstract

This review describes preparations and reactions of 4,7-dihalobenzo[b]thiophenes bearing iodine atom(s). A short survey of typical preparative methods for iodobenzo[b]thiophenes and relatively simple benzo[b]thiophenes is included. Reactions of the iodine-containing 4,7-dihalobenzo[b]thiophenes are shown and their application to α helix-inspired artificial molecular architecture is referred.

FREE:PDF (673KB)

Published online: 12th April, 2021

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-21-14459
A One-Pot Approach to Construct 3-(2-Methoxypyridin-3-yl)-4H-chromen-4-ones via Meinwald Rearrangement/Intramolecular Demethylation Annulation of Epoxides

Min-Qi Hu, Ying Zhang, Kai-Li Dai, Li-Fang Yu, Ting Liu, Jie Tang, and Fan Yang*

*Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, PR China

Abstract

A convenient and practical approach for construction of 3-(2-methoxypyridin-3-yl)-4H-chromen-4-ones has been successfully developed by a one-pot Meinwald rearrangement/intramolecular demethylation annulation reaction sequence with easily accessible epoxides as the starting material. The synthetic protocol is of excellent functional group compatibility under mild reaction conditions, and 3-(2-methoxypyridin-3-yl)-4H-chromen-4-ones were obtained in high yields. Moreover, further derivation successfully furnished more complicated derivatives by Suzuki-Miyaura cross-coupling reaction which may provide a promising potential application in exploring biological activity of 3-aryl-4H-chromen-4-ones.

FREE:Supporting Info. (3.1MB)PDF (753KB)

Published online: 12th April, 2021

Paper | Regular issue | Prepress
DOI: 10.3987/COM-21-14461
Three-Component Reaction of Arynes, Quinolines, and Chloroform: Two-Step Synthesis of 2-Quinolinones from Quinolines

Kentaro Okuma,* Shiho Inomata, Yuxuan Qu, and Noriyoshi Nagahora

*Faculty of Science, Fukuoka University, Jonan-ku, Fukuoka 814-0180, Japan

Abstract

Reaction of quinoline with benzyne prepared from benzenediazonium-2-carboxylate and chloroform gave 1-phenyl-2-trichloromethyl-1,2-dihydroquinoline in 79% yield. Basic hydrolysis of dihydroquinoline by KOH resulted in the formation of 2-quinolinone in 85% yield.

FREE:Supporting Info. (1.1MB)PDF (891KB)

Published online: 6th April, 2021

Paper | Regular issue | Prepress
DOI: 10.3987/COM-21-14448
Synthesis and Biological Activities of Some New Phosphorus Compounds Containing Pyranopyrazole Moiety

Tarik E. Ali,* Mohammed A. Assiri, Hafez M. El-Shaaer, Somaia M. Abed-Kariem, Wafaa R. Abdel-Monem, Somaya M. El-Edfawy, Noha M. Hassanin, Ali A. Shati, Mohammad Y. Alfaifi, and Serag Eldin I. Elbehairi

*Department of Chemistry, Faculty of Science, King Khalid University, Abha, Saudi Arabia.

Abstract

A simple method for construction of functionalized pyranopyrazoles containing phosphoramide and phosphonate groups via one-pot reaction was achieved. The methodology depended on the reaction of 6-amino-3-methyl-1,4-diphenyl-1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile (3) with triethyl phosphite and hexaethylphosphoramide and so with diethyl phosphite in the presence of chloroacetyl chloride or carbon disulfide. The products were screened for their antimicrobial, antioxidant and antiproliferative properties. Compound 7 displayed promising antimicrobial and antioxidative properties. Also, compound 8 showed potent cytotoxic effects against MCF-7, HepG-2 and HCT-116 cancer cells with IC50 values in range 5.3 ± 0.9 to 7.5 ± 0.6 μg/mL. Acridine orange and ethidium bromide were used for the detection of viable, apoptotic, and necrotic cells. The early apoptotic cell death was observed by the compounds in all types of the treated cells. Compounds 5, 7 and 8 induced high percentage of necrosis towards all treated cells. The late apoptosis was recorded as a high rate after treatment with compound 3 in HepG-2 cells.

FREE:PDF (1.5MB)

Published online: 5th April, 2021

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-21-14450
Facile Access to Highly-Substituted Dihydrofurans Using Resonated Vinylpentanedione Radicals Generated by Mn(III)-Based Oxidation

Sousuke Oka, Shintaro Hashimoto, Kazuki Hisano, and Hiroshi Nishino*

*Department of Chemistry, Graduate School of Science, Kumamoto University, Kurokami 2-39-1, Chûou-Ku, Kumamoto 860-8555

Abstract

Useful and easy access to highly-substituted dihydrofurans, which convert into various acetals, was established using the common Mn(III) oxidation. The key point is to use resonated vinylpentanedione radicals that cyclize to produce the desired acetoxydihydrofurans which are transformed into the hemiacetals and acetals in good yields under very mild conditions.

FREE:Supporting Info. (2.9MB)PDF (353KB)

Published online: 2nd April, 2021

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-21-14423
An Efficient SeO2/FeCl3 Promoted Acylation:Intramolecular Friedel-Crafts Reaction Leading to a One-Pot Synthesis of Wrightiadione and Its Derivatives

Huan Zhang, Qi Wang, Lu Huang, Ziye Tian, Shunguang Zhang,* and Youlai Zhang*

*Tianjin Key Laboratory of Drug Targeting and Bioimaging, School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin 300384, P.R. China.

Abstract

Wrightiadione has been shown to exhibit a broad range of biological activities. An efficient and straightforward synthetic method for generating wrightiadione and its derivatives which contain a unique tetracyclic isoflavone moiety was developed. This unprecedented one-pot route utilizes a wide spread of substrates through three-step tandem Riley oxidation/Friedel-Crafts reaction/oxidation with SeO2/FeCl3 in moderate yield.

FREE:Supporting Info. (1.9MB)PDF (898KB)

Published online: 30th March, 2021

Review | Regular issue | Prepress
DOI: 10.3987/REV-21-955
The Fascinating Chemistry of Mesoionic 4-Trifluoroacetyl-1,3-oxazolium-5-olates and Related Compounds

Ryosuke Saijo and Masami Kawase*

*Faculty of Pharmaceutical Sciences, Matsuyama University, 4-2 Bunkyo-cho, Matsuyama, Ehime 790-8578, Japan

Abstract

This review illustrates the unexpected and unique transformation of mesoionic 4-trifluoroacetyl-1,3-oxazolium-5-olates (4-TFMK-münchnones) on treatment with different nucleophiles. A trifluoromethyl group that cannot be synthesized by the usual methods is incorporated in the products. The research discussed in this review is focused on the rich chemistry of 4-TFMK-münchnones. In particular, we highlight the recent advances in their use in contemporary organic synthesis, primarily of trifluoromethyl-substituted heterocycles. The chemistry of related mesoionic compounds is also discussed.

FREE:PDF (831KB)

Published online: 30th March, 2021

Communication | Regular issue | Prepress
DOI: 10.3987/COM-21-14433
Acylative Desymmetrization of Glycerol Derivatives by Chiral DMAP Derivatives

Hiroki Mandai,* Kosuke Ashihara, Koichi Mitsudo, and Seiji Suga*

*Department of Pharmacy, Faculty of Pharmacy, Gifu University of Medical Science, 4-3-3 Nijigaoka, Kani, Gifu, 509-0293

Abstract

An efficient enantioselective acylative desymmetrization of glycerol was developed by using a chiral DMAP derivatives 1e having a 1,1ʹ-binaphthyl unit. The reactions required only 0.1 mol% of the catalyst and showed moderate to good enantioselectivity (up to 94:6 er). Control experiments revealed that the first acylation of a glycerol derivative proceeded selectively rather than the second acylation to give diacylate.

FREE:Supporting Info. (2.3MB)PDF (510KB)

Published online: 30th March, 2021

Paper | Regular issue | Prepress
DOI: 10.3987/COM-21-14443
Facile Preparation of 2-Aryl-3-iodopyrroles with N-Tosyl 4-Aryl-3-butyn-1-ylamines, I2, and tBuOK

Kaho Shibasaki, Hiroki Naruto, and Hideo Togo*

*Graduate School of Science, Chiba University, Yayoi-cho 1-33, Inage-ku, Chiba 263-8522, Japan

Abstract

Treatment of N-tosyl 4-aryl-3-butyn-1-ylamines with I2 and K2CO3, followed by the reaction with tBuOK under mild conditions gave 2-aryl-3-iodopyrroles in good yields. The present approach is a one-pot method for the preparation of 2-aryl-3-iodopyrroles from N-tosyl 4-aryl-3-butyn-1-ylamines, which could be easily prepared from aryl iodides, N-(3-butyn-1-yl)phthalimides, and p-toluenesulfonyl chloride.

FREE:Supporting Info. (8.9MB)PDF (760KB)

Published online: 26th March, 2021

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-21-14435
Anti-Tobacco Mosaic Virus Isoindolin-1-ones from the Stems of Nicotiana tabacum

Jian-Duo Zhang, Xin Liu, Li Xu, Jia-Rui Jiang, Le-Le Deng, Wen-Wu Yang, Xue-Mei Li, Guang-Yu Yang, Tao Zhou,* and Feng-Xian Yang*

*Technology Center, China Tobacco Yunnan Industrial Co., Ltd., Kunming, Yunnan 650231, China

Abstract

Three new (1-3) and three known (4-6) isoindolin-1-ones were isolated from the stems of Nicotiana tabacum. Their structures were determined by means of HRESIMS and extensive 1D and 2D NMR spectroscopic studies. Compounds 1-3 were tested for their anti-tobacco mosaic virus (anti-TMV) activitiy. The results showed that compounds 1-3 showed high anti-TMV activity with inhibition rates of 42.6, 46.7 and 38.5% at the concentration of 20 μM, respectively. These rates are higher than that of ningnanmycin, a positive control.

FREE:Supporting Info. (460KB)PDF (851KB)

Published online: 23rd March, 2021

Review | Regular issue | Prepress
DOI: 10.3987/REV-21-957
Synthesis and Structure−Activity Relationship Study of Intervenolin, an Antitumor and Anti-Helicobacter Pylori Quinolone Natural Product

Takumi Watanabe*

*Institute of Microbial Chemistry, Tokyo (BIKAKEN), 3-14-23 Kamiosaki Shinagawa-ku, Tokyo 141-0021, Japan

Abstract

This review article overviews the chemistry and biology of intervenolin, a quinolone natural product bearing unusual substituents. Intervenolin was isolated as a modulator of tumor–stroma interactions, communication between tumor cells and surrounding normal cells to regulate tumor-associated events including proliferation. The synthesis of intervenolin by the author employs thiocyanate–isothiocyanate rearrangement and Suzuki–Miyaura cross coupling as key reactions, which was utilized in structure–activity relationship studies. The SAR studies generated analogs that are effective in vivo. Moreover, several intervenolin and analogs also showed anti-Helicobacter pylori activity. Mechanistic aspects of these biological activities, and synthetic study on structurally related natural products by Spring and co-workers are also discussed.

FREE:PDF (2.8MB)

Published online: 23rd December, 2020

Review | Regular issue | Prepress
DOI: 10.3987/REV-20-948
Imidazole Chemistry in Crop Protection

Clemens Lamberth*

*Syngenta Crop Protection AG, Research Chemistry, Schaffhauserstrasse 101, CH-4332 Stein, Switzerland

Abstract

An overview is given of the significance of the imidazole scaffold in crop protection chemistry. The main herbicidally, fungicidally and insecticidally active imidazole classes are presented, together with their synthesis routes, modes of action and biological efficacies. Also, partially and fully saturated imidazole derivatives, such as imidazolines and imidazolidines, oxygenated derivatives, such as imidazolinones and hydantoins as well as annulated derivatives, such as benzimidazoles, are covered. In addition, also the role of imidazoles as intermediates or reagents in the synthesis of other agrochemicals is reported.

FREE:PDF (1.3MB)

Published online: 21st December, 2020

Review | Regular issue | Prepress
DOI: 10.3987/REV-20-949
Recent Advances in Synthetic Transformations with Robust Yet Reactive B(Dan) Moiety

Jialun Li and Hiroto Yoshida*

*Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima 739-8526, Japan.

Abstract

Recent advances in the direct B(dan)-installing reactions (dan = naphthalene-1,8-diaminato) into organic frameworks by utilizing (pin)B–B(dan) or H–B(dan) as a B(dan) source, and the direct cross-coupling of dan-substituted organoboron compounds therefrom are described.

FREE:PDF (2.4MB)

Published online: 30th November, 2020

Review | Regular issue | Prepress
DOI: 10.3987/REV-20-944
Highly Oxidized γ-Lactam-Containing Natural Products: Total Synthesis and Biological Evaluation

Kosaku Tanaka III,* Hiroshi Kogen, and Kenichi Kobayashi*

*Graduate School of Pharmaceutical Sciences, Health Sciences University of Hokkaido; 1757 Kanazawa, Tobetsu-cho, Ishikari-gun, Hokkaido 061-0293, Japan

Abstract

γ-Lactam is a ubiquitous structure found in the natural products. A number of highly oxidized γ-lactam-containing natural products are produced by various fungi. These compounds often show a wide range of biological activities because their multiple internal reaction sites, which arise from the high oxidation state of the compounds, can react with biological nucleophiles. Due to their high reactivity and dense functionality, total syntheses of these molecules require strict control of the inherent reactivity and the appropriate design of synthetic intermediates. This review focuses on the recent total syntheses of some highly oxidized γ-lactam-containing natural products, including fused bicyclic (epolactaene, NG-391, lucilactaene, L-755,807), spirocyclic (azaspirene, pseurotin A, E, and F2, cephalimysin A–C, FD-838, and berkeleyamide D), and tricyclic (rubrobramide and talaramide A) skeletons, and on the structure-activity relationship studies of related molecules.

FREE:PDF (3.3MB)

Published online: 9th November, 2020

Review | Regular issue | Prepress
DOI: 10.3987/REV-20-943
Systematic Search for Transition States in Complex Molecules: Computational Analyses of Regio- and Stereoselective Interflavan Bond Formation in Flavan-3-ols

Daisuke Urabe* and Keisuke Fukaya

*Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan

Abstract

This review describes our recent work on a systematic search for transition states in transformations of complex molecules. The method features a combination of a conformational search method using constrained models to create a large library of transition-state candidates, and subsequent density functional theory (DTF)-based transition state calculations for the candidates. The method is applicable to calculation of transition states for inter- and intramolecular interflavan bond formation in flavan-3-ols to reproduce experimental results for highly regio- and stereoselective C-C bond formation. The specific roles of van der Waals interactions in the transition states can be visualized by NCIPLOT mapping to show the importance of weak but attractive interactions for selective interflavan bond formation.

FREE:PDF (1.9MB)

Published online: 22nd October, 2020

Review | Regular issue | Prepress
DOI: 10.3987/REV-20-940
Synthetic Approaches for Heteroannulated Chromones Fused Various Heterocyclic Systems

Salsabeel H. Hashiem, Magdy A. Ibrahim, Al-Shimaa Badran,* Nasser M. El-Gohary, and Hassan A. Allimony

*Department of Chemistry, Faculty of Education, Ain Shams University, Roxy 11711, Cairo, Egypt

Abstract

The main focus of this review summarized the different methods utilized for the synthesis of chromone annulated with different heterocyclic rings such as pyrroles, furans, pyrazole, imidazole, benzene, naphthalene, quinolone……and others.

FREE:PDF (3.5MB)
24 data found. 1 - 24 listed