HETEROCYCLES

■ Intramolecular 1,3-Dipolar Cycloadditions of Arynyl Azides on Alkyl and Alkenyl Groups

Otohiko Tsuge,* Kazunori Ueno, and Akitaka Inaba

*Research Institute of Industrial Science, Faculty of Engineering, Kyushu University, 6-1, Kasuga-koen, Kasuga 816-8580, Japan

Abstract

Aryl azides 2 containing alkynyl or alkenyl group as dipolarophile were prepared and thermally decomposed in benzene. Azides 2a-3d gave the corresponding 1,3-cycloadducts, fused-ring l,2,3-triazoles 8a-8d, while bridgehead nitrogen aziridines 9 and 10, were obtained from 3e and 3f, probably via unstable δ²-1,2,3-triazolines.

■ Syntheses and Reactions of 2-Indol-3-yl-1,3-oxathiolium Salts

Yoshinori Tominaga, Yoshiro Matsuda, and Goro Kobayashi*

*Faculty of Pharmaceutical Sciences, Nagasaki University, 1-14, Bunkyo-machi, Nagasaki 852-8521, Japan

Abstract

The reaction of methyl indole-3-dithiocarboxylates (la,b,c,d) with phenacyl bromide in acetone gave 2-indol-3-yl-1,3-oxathiolium bromides (2a,b,c,d) which reacted with active methylene compounds to form 2-indol-3-ylthiophene derivatives (3a,b,c,d).

■ The Reaction of Tetrapiperidinoethylene with CH-Acidic Compounds

Otohiko Tsuge,* Tamio Iimure, and Masako Horie

*Research Institute of Industrial Science, Faculty of Engineering, Kyushu University, 6-1, Kasuga-koen, Kasuga 816-8580, Japan

Abstract

Tetrapiperidinoethylene (TPE) reacts with CH-acidic compounds such as acetophenones, 2-acetylthiophene, 3-acetylpyridine, phenylacetonitrile, phenyl ethyl ketone and α-tetralone to afford the corresponding enamines. On the other hand, in the reaction with malononitrile TPE gives the oxamidinium salt.

■ Diels-Alder Reactions of Furans. Synthesis of 7-Oxabicyclo[2.2.1]heptane Derivatives

Teunis A. Eggelte, Henk de Koning,* and Henderikus O. Huisman

*Laboratory of Organic Chemistry, University of Amsterdam, Nieuwe Achtergracht 129,1018 WS Amsterdam, The Netherlands

Abstract

New Diels-Alder reactions of furan and methylfurans with some dienophiles were performed. The adduct from furan and nitroethylene could be used for synthesizing other 7-oxabicyclo[2.2.l]heptane derivatives.

■ A One-step Synthesis of Evodiamine and Rutecarpine

Tetsuji Kametani,* Terumi Higa, Keiichiro Fukumoto, and Masuo Koizumi

*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan

Abstract

Evodiamine (1) and rutecarpine (2) were synthesised by condensation of 3,4-dihydro-β-carboline (5) with the keteneimines (6 and 12) derived from N-methylanthranilic acid (7) and anthranilic acid (10), respectively.

■ An Alternative Synthesis of (±)-Yohimbine

Tetsuji Kametani,* Yoshiro Hirai, and Keiichiro Fukumoto

*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan

Abstract

Birch reduction of 16-carboxyl-l5,16,17,18,19, 20-hexadehydro-17-methoxyyohimbane (8), followed by esterification gave 15,17,18,20-tetradehydro-17-methoxy- 16-methoxycarbonylyohimbane (10), which was treated with oxalic acid and then hydrochloric acid to afford 15,16-dehydroyohimbinone (2) that had been already correlated with (±)-yohimbine (4).

■ Calculated Reactivity Indices and Bond Distances for Thieno[2,3-c]pyridazine

Stewart W. Schneller* and Per Njal Skancke

*Department of Chemistry, University of South Florida, Tampa, Florida 33620, U.S.A.

Abstract

The calculated reactivity indices and bond distances for thieno[2,3-c]pyridazine, an unknown heterocycle, are presented.

■ Synthesis of a Fantastic Analgesic N-Cyclopropylmethyl-3-hydroxy-9-azamorphinan

Tetsuji Kametani,* Kazuo Kigawsawa, Mineharu Hiiragi, Nagatoshi Wagatsuma, Osamu Kusama, and Tsuneo Uryu

*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan

Abstract

Optical resolution of dl-N-cyclopropylmethyl-3-hydroxy-9-azamorphinan (I) was successfully effected with O,O-dibenzoyl-d-tartaric acid or (2R : 3R)-2’-nitrotartranilic acid as the result-ion agent. The optically active compounds thus obtained were tested for their analgesicactivity and antagonistic effect of morphine analgesia.

■ Synthtetic Studies on Mitomycins. An Alternative Synthesis of 2,3-Dihydro-1H and 9H-pyrrolo[1,2-a]indoles by Transannular Ring Closure

Tsuneo Itoh,* Toju Hata, and J. William Lown*

*School of Pharmaceutical Sciences, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan

Abstract

The synthesis of substituted 1,2,3,4,5,6-hexahydro-2,3-benzazocin-5-ones and their conversion via trans-annular ring closure to the 2,3-dihydro-1H and 9H-pyrrolo[l,2-a]indole ABC parent ring system of the antitumor antibiotic mitomycin C is described.

■ Equisetumalkaloide; Stand der Chemischen Erforschung 1975

Conrad Hans Eugster*

*Institute of Organic Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland

Abstract

Herrn Professor Tsunematsu Takemoto anlässlich seiner Emeritierung mit allen guten Wünschen für die Zukunft gewidmet.

■ Cyclopeptide Alkaloids Containing a Styrylamine Ring Unit

Rudolf Tschesche*

*Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, D-5300 Bonn 1, Germany

■ Imino Acids and N-Heterocyclic Amino Acids from Plants

Leslie Fowden*

*Rothmsted Experimental Station, Harpenden, Herts, U.K.

Abstract

Plants produce a large number of imino acids and amino acids with a N-heterocyclic group. The chemistry of these compounds is reviewed, and information about their distribution and biogenesis in plants is provided.

■ The Indole Alkaloids of Japanese Plants; Structures and Reactions

Shin-ichiro Sakai*

*Faculty of Pharmaceutical Sciences, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan

Abstract

Indole alkaloids of several Japanese plants have been studied. Some chemical conversion works have also been made utilizing them as the starting materials.

■ Studies on Indole Alkaloid Biosynthesis. Part I. Alkaloids Containing the Normal Tryptophan Side Chain. The Later Stages

James P. Kutney*

*Department of Chemisry, University of British Columbia, Vancouver 8, V5T 1W5 , Canada

Abstract

A summary of the experiments relating to the biosynthesis of various indole alklaoids and performed in the author’s laboratory is presented. The results as they relate to the later stages of the biosynthetic pathways in the Aspidosperma and Iboga bases are discussed in terms of the experiments performed in Catharanthus roseus G. Don (Vinca rosea L.) with the alkaloids vindoline and catharanthine. The plant, Vinca minor L., has been employed for obtaining some information about the eburnamine-vincamine series of alkaloids. The implications of these results and the remaining questions to be answered before definitive pathways can be proposed are also discussed.¡

■ Organic and Biological Aspects of Berberine Alkaloids

Yoshikazu Kondo*

*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan

Abstract

Recent chemical and biological progresses of berberine alkaloids have been reviewed.