HETEROCYCLES

■ Contents

■ Introduction of an N1 Unit to Monoenes or 1,6-Dienes Using Chloramine-T-Silver Nitrate: A New Route to Aziridines or Bicyclic Pyrrolidines

Satoshi Minakata, Daisuke Kano, Ryoko Fukuoka, Yoji Oderaotoshi, and Mitsuo Komatsu*

*Department of Applied Chemistry, Graduate School of Science, Osaka University, 2-1 Yamadaoka, Suita, Osaka 560-0871, Japan

Abstract

Aziridine derivatives are synthesized from a variety of olefins using commercially available Chloramine-T as a nitrogen source in the presence of AgNO₃. The method is applicable to a tandem cyclization of 1,6-dienes accompanied by an N1 unit incorporation to afford bicyclic pyrrolidine derivatives.

■ First Isolation of cis- and trans-1,3,4-Selenadiazolines from Pivarophenone Hydrazones

Kentaro Okuma,* Kento Kubo, and Yoshinobu Yokomori

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

Abstract

Sterically congested cis- and trans-1,3,4-selenadiazolines were isolated by one-pot reaction of pivalophenone hydrazones with diselenium dibromide, which suggested in situ formation of selenoketone and diazoalkane intermediates. Thermolysis of these compounds gave symmetrical olefins, whereas oxidation afforded the corresponding azines.

■ Facile Synthesis of Unsymmetrical 1,1-Diamino-2-nitroethenes and Functionalized Amidoximes

Nagatoshi Nishiwaki,* Yoshikazu Okajima, Mina Tamura, Noriko Asaka, Kazushige Hori, Yasuo Tohda, and Masahiro Ariga*

*Department of Chemistry, Osaka Kyoiku University, 4-698-1 Asahigaoka, Kashiwara, Osaka 582-8582, Japan

Abstract

Aminolysis of nitroisoxazolone affords unsymmetrical 1,1-diamino-2-nitroethenes and carbamoylamidoximes with simple experimental manipulations.

■ Chemistry of Indoles Carrying a Basic Function. Part VII. A New Aspect of Stobbe Reaction

István Moldvai, Eszter Temesvári-Major, Mária Incze, Tünde Platthy, Eszter Gács-Baitz, and Csaba Szántay*

*Institute of Chemistry, Chemical Research Center, Hungarian Academy of Sciences, H-1025 Budpest II, Pusztaszeri ut 59-67, P.O. Box 17, Hungary

Abstract

While performing Stobbe reactions of a succinic diester derivative (1) different routes were found leading to different indole derivatives (2-5) depending on the reaction conditions applied, thus widening the scope and limitation of this useful procedure. Simpler pyrrolidine (13) and piperidine derivatives (14, 15) were also achieved through application of the intramolecular Stobbe reaction.

■ Useful Synthesis of Various Thiazole and Polythiazolyl Derivatives from Thiocarboxamide and β-Bromoacyl Compound

Atsushi Nagasaki, Yasuhito Adachi, Yasuchika Yonezawa, and Chung-gi Shin*

*Laboratory of Organic Chemistry, Faculty of Engineering, Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama 221-8686, Japan

Abstract

Useful synthesis and thiazole ring formations of the methyl β-bromo-α-oxoalkanoate and β-bromoacyl group containing-5-methylthiazole-4-carboxylate, which are very promising compounds for the synthesis of various polythiazole derivatives, were accomplished.

■ Synthesis of Thieno[2,3-b]pyrazines via an Acylation - Deacylation Process of 3,4-Dihydro Precursors

Thomas Erker,* Karin Trinkl, and Franz Pertlik

*Institute of Pharmaceutical Chemistry, University of Vienna, Althanstraße 14, A-1090 Vienna, Austria

Abstract

In the first step 3, 4-dihydrothieno[2,3-b]pyrazines (1, 2 and 4) were N-acylated by the acyl chlorides followed by a deacylation process mediated by triethylamine to give thieno[2,3-b]pyrazines . In a final rection the excess of the appropriate acyl chlorides react with the free hydroxy residue to afford compounds (15, 16 or 17).

■ Acylated Cyanidin Glycosides from the Purple-red Flowers of Anemone coronaria

Kenjiro Toki, Norio Saito, Atsushi Shigihara, and Toshio Honda*

*Faculty of Pharmaceutical Sciences, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan

Abstract

Two novel polyacylated cyanidin glycosides were isolated from the purple-red flowers of Anemone coronaria ‘St. Brigid’ together with a known polyacylated cyanidin glycoside (Anemone Purple Anthocyanin 1). These novel pigments were identified as cyanidin 3-O-[2-O-(2-O-(trans-caffeoyl)-β-D-glucopyranosyl)-6-O-malonyl-β-D-galactopyranoside]-7-O-[6- O-(trans-caffeoyl)-β-D-glucopyranoside]-3’-O-β-D-glucuronopyranoside and its demalonyl derivative.

■ A New Synthetic Method for Substituted 2,4-Dihydro-3H-1,2,4-triazol-3-ones and 3-thiones via 1,4-Dialkyl-5-phenylthio-1H-1,2,4-triazolium Salts

Ikuo Kawasaki, Akane Domen, Shin-ya Kataoka, Kazuya Yamauchi, Masayuki Yamashita, and Shunsaku Ohta*

*Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8412, Japan

Abstract

Novel 2,4-di- and 2,4,5-trialkyl-2,4-dihydro-3H-1,2,4-triazol-3-ones and 2,4-dialkyl-2,4-dihydro-3H-1,2,4-triazole-3-thiones were prepared by the reaction of 1,4-dialkyl-5-phenylthio-1,2,4-triazolium salts with aqueous potassium carbonate or sodium sulfide in DMF, respectively.

■ Novel [12+2] Cycloaddition of 2H-4,9-Methanocycloundeca[b]furan-2-ones with Enamines: Synthesis and Properties of 4,9-Methanocyclopentacycloundecenes and a Benzo-annulated Derivative

Makoto Nitta,* Akira Akaogi, and Hiroki Tomioka

*Department of Chemistry, School of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555, Japan

Abstract

Novel cycloaddition reactions of 2H-4,9-methanocycloundeca[b]furan-2-one and 3-chloro-substituted derivative with enamines underwent novel [12 + 2] cycloaddition reaction followed by decarboxylation and elimination of amine to give 4,9-methanocyclopentacycloundecene derivatives in modest yields. Upon treatment of DDQ, cyclohexane-annulated 5-chloro-4,9-methanocyclopentacyclo-undecene was dehydrogenated easily to give the first example of a benzo-annulated 4,9-methanocyclopentacycloundecene ring system. Chemical as well as spectroscopic properties of them were studied, and it was clarified that benzo-annulation causes an appreciable degree of bond alternation and reduced ring current.

■ Three New Eremophilenolides from Ligularia hiberniflorum (Makino) Kitam.

Munehiro Nakatani,* Saori Maeda, Kenji Higashi, Junichi Kurawaki, Hiroaki Okamura, and Tetsuo Iwagawa

*Department of Chemistry and Bioscience, Faculty of Science, Kagoshima University, 1-21-35 Korimoto, Kagoshima 890-0065, Japan

Abstract

Three new eremophilenolides, 3β-angeloyloxy-6β,8α-dimethoxy-eremophil-7(11)-en-12,8β-olide, 3β-angeloyloxy-6β-hydroxy-8α-methoxy-eremophil-7(11)-en-12,8β-olide and 3β-angeloyloxy-6β-hydroxy-8β-methoxy-eremophil-7(11)-en-12,8α-olide, were isolated from the rhizomes of Ligularia hiberniflorum (Makino) Kitam. These structures were elucidated on the basis of spectroscopic evidence. The CD spectra of the compounds are also briefly discussed.

■ Electrophilic Substitution in Indoles, Part 20’ Hammett Correlations of the Coupling of Aryldiazonium Tetrafluoro- borates with Indole and Its 1-, 2- and 3-Methyl Derivatives

Selda Aldemir, Hulya Kahyaoglu, and Meysun I. Abdullah*

*Department of Chemistry, University of Nigde, Nigde 51200, Turkey

Abstract

Hammett plots for the coupling of a range of substituted aryldiazonium tetrafluoroborate salts in dry acetonitrile with indole and its 1-, 2- and 3-methyl derivatives gave linear relationships, with ρ values ca. of +2.60, +2.54, +2.40 and +3.60 respectively.

■ Synthesis of 4-[4-(N,N-Dimethylsulfamoyl)piperazin-1-yl]quinolines Derivatives as Sorbitol Dehydrogenase Potential Inhibitors

Didier Varlet, Eric Fourmaintraux, Patrick Depreux,* and Daniel Lesieur

*Institut de Chimie Pharmaceutique, Albert Lespagnol, Université de Lille 2, 3, rue du Professeur Laguesse, BP 83, 59006 Lille Cedex, France

Abstract

Synthesis of various quinolines, substituted in position 4 by [4-(N,N-dimethylsulfamoyl)piperazin-1-yl] group and in position 2 by different groups such as hydrogen, methyl, hydroxymethyl, formyl or carboxyl is described. Besides, we have synthesized derivatives of 8-hydroxyquinoline.

■ Constituents of Leaves of Phellodendron chinense var. glabriusculum

Tian-Shung Wu,* Meei-Yu Hsu, A. G. Damu, Ping-Chung Kuo, Chung-Ren Su, Chia-Ying Li, and Han-Dong Sun

*Department of Chemistry, Natioanl Cheng Kung University, 1. Ta-Shiueh Rd., Tainan, 70101, Taiwan, R.O.C.

Abstract

The leaves of Phellodendron chinense var. glabriusculum yielded three new flavanones, phellodensin D (1), phellodensin E (2), and phellodensin F (3) along with five known compounds, amurensin (4), phellamurin (5), methyl caffeate (6), β-sitosterol (7), and pheophytin-a (8). The structural assignment of new compounds was based on spectroscopic studies.

■ Synthesis of an Annulenoannulenone, 3H-Benzo[e]cycl[3.3.2]azin-3-one

Yoshiro Matsuda,* Shinya Kohra, Keisuke Katou, Takashi Uemura, and Kouhei Yamashita

*Faculty of Environmental Studies, Nagasaki University, 1-14, Bunkyo-machi, Nagasaki 852-8521, Japan

Abstract

A new nitrogen-bridged annulenoannulenone, 3H-benzo[e]cycl[3.3.2]-azin-3-one (10a) was synthesized from the starting phenylpyridine (6) via the reaction of the indolizine derivative (9a) with polyphosphoric acid (PPA) as the key step.

■ The One-Pot Conversion of Pyrimidinone Derivatives into Substituted Pyrimidines Using Diphenylphosphinic Chloride under a Mild Condition

Ken-ichi Tanji, Takeshi Yokoi, and Osamu Sugimoto*

*Laboratory of Organic Chemistry, School of Food and Nutritional Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan

Abstract

Pyrimidinone derivatives reacted with diphenylphosphinic chloride followed by addition of nucleophiles to afford substituted pyrimidine derivatives at a mild temperature (20-66 °C).

■ Molecular Complexes of Heteroaromatic N-Oxides and Their Reactions with Nucleophiles

Alexander V. Ryzhakov,* Vladimir P. Andreev, and Ludmila L. Rodina

*Department of Biochemistry and Organic Chemistry, Petrozavodsk University, Pr. Lenina 33, Petrozavodsk, 185680, Russia

Abstract

It was shown that binding of heteroaromatic N-oxides in molecular complexes with appropriate v- and π-acceptors facilitates the nucleophilic substitution and addition reactions.

■ Synthetic Utilities of N-Acylpyrazoles

Choji Kashima

*Department of Chemistry, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba-shi, Ibaraki, 305-8571, Japan

Abstract

Little attention had been paid to N-acylpyrazoles, because they are 20 times less reactive than the corresponding N-acylimidazoles. From this lower reactivity, N-acylpyrazoles seem to be sufficiently stable as the starting materials, and should be applied to the controlled reactions such as the chemo-, the regio- and the stereoselective reactions. In this review, the preparation of N-acylpyrazoles and their utilities for the organic syntheses are reviewed.