Prepress

Regular Issues

14 data found. 1 - 14 listed

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 JM (14), 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: 29th May, 2019

Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14076
Total Synthesis of Thermoactinoamide A and Its Analogue

Yueguang Sun,* Hang-bin Li, Rong Zhou, Hailin Wang, Pengju Feng,* and Shihai Xu*

*Department of Chemistry, Jinan University, 601 Huangpu Avenue West, Tianhe District 10632, China

Abstract

Thermoactinoamide A, showing remarkable antibacterial properties, is a novel cyclic hexapeptide which was originally isolated from thermophilic bacterium. We disclosed here the first total synthesis of thermoactinoamide A and its analogue, anti-thermoactinoamide A, by the Fmoc solid-phase peptide synthesis and subsequent efficient macrolactamization. Thermoactinoamide A and its analogue can be obtained in 74% and 46% overall yield respectively without any isomerization under the developed methodology.

FREE:Supporting Info. (1.5MB)PDF (790KB)

Published online: 28th May, 2019

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14053
Synthesis and Optical Properties of Polyarylimidazole Derivatives Containing Naphthyl Groups In the 4,5-Positions for Coated and Non-Doped OLED Materials

Keiji Mizuki,* Daiki Sakai, Yuri Hatashima, and Taizo Hatta

*Department of Nanoscience, Faculty of Engineering, Sojo University, 4-22-1, Ikeda, Kumamoto-shi, 860-0082, Japan

Abstract

In this study, we describe the development of an imidazole emitting material, characterized by low concentration quenching via a bulky substituent group, for coated and non-doped OLEDs. Specifically, we synthesized novel 1,2,4,5-tetraarylimidazoles that have naphthyl groups replacing the bulky aryl groups at the 4,5-positions and investigated their optical, concentration quenching, thermal, and coating properties. We observe that the emitting materials had low concentration quenching properties and fluorescence occurred even in the film coating state.

FREE:PDF (2MB)

Published online: 28th May, 2019

Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14077
Total Synthesis of Proposed Structure of Azepinobisindole Alkaloid Rhodozepinone

Tomoki Itoh and Takumi Abe*

*Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-0293, Japan

Abstract

Total synthesis of the proposed structure of azepinobisindole alkaloid rhodozepinone has been accomplished from simple starting materials in 4 steps for the first time.

FREE:Supporting Info. (1.9MB)PDF (231KB)

Published online: 23rd May, 2019

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14070
Thymidine, 2-Thiothymidine, and 2-Selenothymidine: Comparison of Mismatch Discriminations

Takaki Habuchi, Takao Yamaguchi, and Satoshi Obika*

*Pharmaceutical Science, Osaka University, 1-6 Yamadaoka, Suita, Osaka 560-0871, Japan

Abstract

Oligonucleotides modified using 2-thiothymidine (S2T) or 2-selenothymidine (Se2T), which are thymidine analogs bearing either sulfur or selenium atoms, respectively, have been independently shown to suppress the formation of mismatched wobble base pairs with guanine when forming a duplex with single stranded DNA. However, limited data comparing the base discriminations of S2T- and Se2T-modified oligonucleotides, especially toward single stranded RNA, are available. Here, we report a comprehensive data set of the base discriminations of S2T- and Se2T-modified oligonucleotides toward both single stranded DNA and RNA. Our results demonstrate that S2T- and Se2T-modified oligonucleotides have similar base discrimination abilities. An important feature observed in both the S2T- and Se2T-modified oligonucleotides is their extremely high base discrimination toward single stranded RNA. Thus, S2T and Se2T modifications may be useful for therapeutic oligonucleotides targeting single stranded RNAs.

FREE:PDF (284KB)

Published online: 23rd May, 2019

Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14086
Uncariagambiriines B and C, Alkaloid-Catechin Hybrids from Uncaria gambir Leaves

Mutsumi Oshima, Hiroe Aoyama, Yuuki Shimozu, Shoko Taniguchi, Takanori Miura, and Tsutomu Hatano*

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

Abstract

Gambiers, aqueous extracts from the leaves and twigs of Uncaria gambir, are used medicinally in Asian countries. Previously, we reported the isolation of uncariagambiriine (1) from U. gambir leaves, and its unique structure regarded as a catechin-alkaloid hybrid. Our continuing studies led to the isolation of two previously undescribed compounds named uncariagambiriines B (2) and C (3), in addition to the flavonoid glycosides, hyperoside and isoquercitrin. The structures of 2 and 3, isomeric to 1, were elucidated based on their spectral data.

FREE:PDF (579KB)

Published online: 22nd May, 2019

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14087
An Efficient Three-Component Synthesis of Novel Spiro[pyrazole-4,2’-quinazoline] Derivatives

Hayate Nagabuchi, Eiichi Masumoto, Fumi Okabe-Nakahara, and Hiroshi Maruoka*

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

Abstract

A simple, efficient, and three-component procedure has been developed for the synthesis of a series of spiropyrazol-3-one derivatives containing dihydroquinazoline moiety by the reaction of 1H-pyrazole-4,5-diones, 2-aminobenzophenones, and ammonium acetate in moderate to good yields. This method provides several advantages such as operational simplicity, shorter reaction time, and higher yields. All the synthesized compounds were characterized by spectroscopic analysis.

FREE:PDF (407KB)

Published online: 21st May, 2019

Review | Regular issue | Prepress
DOI: 10.3987/REV-19-905
Synthetic Methods of 1,3,2-Diazaphosphinine Systems

Tarik E. Ali,* Mohammed A. Assiri, Ahmed M. Fouda, Mohamed M. Hassan, and Noha M. Hassanin

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

Abstract

The present review considers all the literature data on methods developed for the synthesis of 1,3,2-diazaphosphinine systems starting from their appearance up to end 2018. The described main methods depended on the cyclization of 1,3-diamines, 1,2-aminoamide (β-aminoamide) and 1,2-aminonitrile (β-aminonitrile) compounds with phosphorus halides and sulfides.

FREE:PDF (1.8MB)

Published online: 21st May, 2019

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14085
A Mild and Efficient Ga(OTf)3-Catalysed Friedländer Reaction for the Synthesis of Quinolines

Hani Mutlak A. Hassan* and Iuliana Denetiu

*King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589 80216, Saudi Arabia

Abstract

The application of gallium triflate [Ga(OTf)3] for the synthesis of quinolines via the Friedländer reaction is described. This mild and straightforward method employed only 1 mol% of Ga(OTf)3 to deliver the quinoline products in excellent yields, demonstrating the high catalytic activity of this rare earth metal triflate.

FREE:PDF (695KB)

Published online: 13th May, 2019

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-19-14075
Synthesis of Steroidal [1,2,4]Triazolo[1,5-a]pyrimidines and Their Antiproliferative Activities

Ning-Juan Fan, Jiang-Jiang Tang, Yuan-Feng Li, Yu-Bin Bai, and Xiao-Min Zhao*

*College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China

Abstract

A facile strategy for the synthesis of steroidal [1,2,4]triazolo[1,5-a]pyrimidines 5a-g and 6a-g has been accomplished via a one-pot reaction of steroidal ketones, aromatic aldehydes and 3-amino-1,2,4-triazole in the presence of potassium tert-butoxide in refluxing tert-butanol. All the synthesized heterosteroids were evaluated for in vitro antiproliferative activity against human cancer cells by sulforhodamine B (SRB) assays. The preliminary results showed that compounds 6a and 6e possessed potent antiproliferative activities.

FREE:Supporting Info. (2.3MB)PDF (610KB)

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)
14 data found. 1 - 14 listed