HETEROCYCLES

■ Contents

■ The Dawn, Evolution and Personal Reminiscences in Studies of Glycosyl Isocyanates and Isocyanides

Yoshiyasu Ichikawa*

*Faculty of Science, Kochi University, 2-5-1, Akebono-cho, Kochi 780-8520, Japan

Abstract

Historical background and personal reflections on my research career studying glycosyl isocyanates and isocyanides are described

■ Microwave Promoted Diels-Alder Reaction of 1,2-Dihydropyridine

Stephen R. Slauson,* Natalia Echeverry, Samantha Copeland, Alessandra Stoj, Melissa A. Kemp, and Maria Simon

*Department of Pharmaceutical Sciences, School of Pharmacy, University of Saint Joseph, 229 Trumbull Street, Hartford, CT 06103, U.S.A.

Abstract

The microwave-assisted Diels-Alder reaction between 1,2-dihydropyridine and activated dienophiles is reported. The conditions facilitate the production of the [2.2.2] scaffold in high yields with simple purification.

■ Protein-Promoted Synthesis of Chromene Derivatives via Biocatalytic Domino Reaction

Long-Hua Zhou,* Wei-Hua Huang, Li-Fang Ma, Yong-Jiu Jin, Fang Chen, and Yu-Ling Zhu

*Physical and Chemical Department, Nanchang Centre for Disease Control and Prevention, Lijing Road 833, Honggutan, Nanchang, 330038, China

Abstract

An efficient and green procedure has been developed for the synthesis of chromenes using 1,3-diketones and ɑ,β-unsaturated aldehydes. The effect of reaction conditions including solvents, water content, molar ratio of substrates and catalyst loading were investigated. A series of chromene derivatives were prepared with moderate to high yields under the catalysis of bovine serum albumin (BSA) in isopropanol successfully. This novel activity of BSA to catalyze the domino reaction is not only of practical significance in expanding the application of biocatalysts, but also providing more convenient synthetic method for green chemistry.

■ A New HBT-Based Fluorescent Probe for Hydrazine Detection in Aqueous Solution

Jing-Hua Dong,* Jia Deng, and Yuan Zhang

*Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, College of Chemistry and Chemical Engineering, Hubei Normal University, 11, Cihu Road, Huangshi, Hubei Province 435002, China

Abstract

A new HBT-based fluorescent probe is designed and synthesized for the detection of hydrazine based on Gabriel-type hydrazinolysis reaction mechanism. The probe responds selectively to hydrazine with obvious turn-on fluorescence. The water sample analysis indicated its great potential in the environment monitoring of hydrazine in aqueous solution.

■ One-Pot Synthesis of Isoindolin-1-ones from Nitroarenes and o-Phthalaldehyde via Indium-Mediated Reductive Condensation Reactions

Eungyung Kim, Mingyeong Jeong, Byung Min Lee, and Byeong Hyo Kim*

*Department of Chemistry, Kwangwoon University, 447-1, Wolgye-Dong Nowon-ku, Seoul, 139-701, Korea

Abstract

Indium-mediated reductive condensation reactions of various nitroarenes with o-phthalaldehyde toward isoindolin-1-ones were investigated. In the presence of indium/AcOH in toluene at reflux, nitroarenes were coupled and cyclized with o-phthalaldehyde to produce corresponding isoindolin-1-ones with reasonable yields.

■ One-Pot Synthesis of 3-Oxo-2H,4H-1,4-benzothiazine-2-carbonitrile Derivatives via Cyclization of Methyl {[2-(Cyanomethyl)sulfanyl]phenyl}carbamate

Kazuhiro Kobayashi,* Kazuki Kawano, 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

A facile method for the synthesis of 3-oxo-2H,4H-1,4-benzothiazine-2-carbonitrile (2-cyano-2H-1,4-benzothiazin-3(4H)-one) derivatives has been developed. Sodium hydride-mediated cyclization of methyl {[2-(cyanomethyl)sulfanyl]phenyl}carbamate, which can be easily prepared from commercially available 2-aminobenzenethiol in two steps, allows the synthesis of 3-oxo-2H,4H-1,4-benzothiazine-2-carbonitrile and its 2-mono- and 2,4-di- alkylated derivatives in one-pot.

■ Vanadium-Catalyzed Achmatowicz and Aza-Achmatowicz Rearrangement Reactions

Wang-Ze Song,* Nan Zheng, Ming Li, Karim Ullah, Jun-Hao Li, Kun Dong, and Yu-Bin Zheng*

*School of Pharmaceutical Science and Technology, Dalian University of Technology, No.2 Linggong Road, Ganjingzi District, Dalian City, Liaoning Province 116024, China

Abstract

A novel and efficient synthesis of substituted pyranones and pyridinones is developed using cumene hydroperoxide as oxidant by vanadium-catalyzed Achmatowicz rearrangement and aza-Achmatowicz rearrangement reactions. It offers a sustainable and environmentally benign approach to access multisubstituted pyranones or pyridinones derivatives.

■ HBr-Promoted Sulfenylation of Pyrazolones and 4-Hydroxycoumarins with N-(Organothio)succinimides

Hongai Jin, Wangyang Wang, Zhaohua Yan,* Rongxing Zhang, Mingchuang He, and Sen Lin*

*College of Chemistry, Nanchang University, No. 999, Xuefu Rd. 330031, China

Abstract

A convenient, effective and metal-free method for the synthesis of C-4 sulfenylated pyrazolones via HBr-promoted sulfenylation of pyrazolones with N-(organothio)succinimides as sulfur sources was developed. The method can be extended to apply for substrates 4-hydroxycoumarins. A series of C-4 sulfenylated pyrazolones and C-3 sulfenylated 4-hydroxycoumarins were smootly synthesized in good to excellent yields.

■ Palladium-Catalyzed One-Pot Approach to 3-(1,3-Diarylprop-2-yn-1-ylidene)oxindoles

Jiyun Lee, Sunhwa Park, Kye Jung Shin, and Jae Hong Seo*

*College of Pharmacy, The Catholic University of Korea, 43 Jinong-ro Wonmi-gu Bucheon, Gyeonggi-do, 420-743, Korea

Abstract

An efficient and stereoselective one-pot approach for synthesizing 3-(1,3-diarylprop-2-yn-1-ylidene)oxindoles has been developed, starting from propiolamide, aryl iodides and arylacetylenes and utilizing two palladium-catalyzed reactions: the Sonogashira and Heck reactions. This method produced (E)-3-(1,3-diarylprop-2-yn-1-ylidne)oxindoles as the major stereoisomers. This is the first time an effective synthetic method for (E)-isomer of these compounds has been reported.

■ Biginelli Reaction of Aliphatic Aldehydes Catalyzed by α-Chymotrypsin: One-Pot Biocatalytic Synthesis of Dihydropyrimidinones

Lei-Han Fu, Zong-Bo Xie,* Jin Lan, Hong-Xia Li, Lian-Sheng Liu, and Zhang-Gao Le*

*Department of Applied Chemistry, East China University of Technology, Guanglan Road 330013, China

Abstract

A green and highly efficient procedure was developed for the one-pot, three-component synthesis of 3,4-dihydropyrimidin-2-(1H)-ones by the condensation of aliphatic aldehydes, β-keto esters, and urea. α-Chymotrypsin from porcine pancreas showed excellent catalytic activity in the reaction. The influences of solvents, temperature, and water content were investigated. The desired products were obtained in 85-96% yields. The methodology generates high yields with a wide range of substrates.

■ One-Pot Synthesis of 6H-Indolo[2,3-b]quinolines from 2-Nitrobenzaldehyde and Indole Derivatives via Domino Reaction

Wei-Nan Zhang, Jiao Xu,* Dao-Lin Wang,* and Zhen-Kai Zhong

*College of Chemistry and Chemical Engineering, Bohai University, 19, Keji Rd., New Songshan District, Jinzhou City, Liaoning Province 121001, China

Abstract

An efficient and simple method for the synthesis of 6H-indolo[2,3-b]- quinolones was described. The construction of this fused heterocycles system was achieved by alkylation–reduction–cyclization domino reaction of 2-nitro- benzaldehyde with indoles using SnCl2 as a promoter in [bmim]Br medium.