HETEROCYCLES

■ Total Synthesis of (±)-Tubulosine and (±)-Deoxytubulosine

Tetsuji Kametani,* Yukio Suzuki, and Masataka Ihara

*Pharmaceutical Institute, Tohoku University, Aramaki, Aoba-ku, Sendai 980-8578, Japan

Abstract

Total synthesis of (±)-tubulosine (1) and (±)-deoxytubulosine (2) by Pictet-Spengler reaction of (±)-4-oxoprotoemetine (6) with serotonin (7) or tryptamine (8) followed by reduction with sodium bis(2-methoxyethoxy)aluminium hydride in pyridine is described.

■ The reaction of Singlet Oxygen with 1-Methoxycyclohexene

Paul D. Bartlett* and Aryeh A. Frimer

*Department of Chemistry, Harvard University, 12 Oxford Street, Cambridge, Massachysetts 02138, U.S.A.

Abstract

1-Methoxycyclohexene (1) on photosensitized oxygenation yields the two allylic hydroperoxides 2 and 3 and the dioxetane 4. In a slower reaction 2, which is still an enol ether, is further photo-oxidized. The initial oxidation products are all thermally unstable, but analytical procedures are described by which their amounts can be determined. The rate of oxygenation and the proportion of 3 are both approximately doubled in benzene compared to acetonitrile as solvent. The mechanism of the reaction is discussed in the light of this and related evidence recently developed for the 2,3-dihydro-4H-pyrans.

■ The Total Synthesis of Mollicellin A

George Büchi* and Paul G. Williard

*Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, U.S.A.

Abstract

The total synthesis of mollicellin A is reported.

■ Photoelectron Spectra of Unsaturated Oxides ll, 2,5-Dihydrofuran Derivatives

Martin Bloch, Edgar Heilbronner,* Taylor B. Jones, and Jean L. Ripoll

*Physikalisch-Chemisches Institut, Universität Basel, Klingelbergstrasse 80, 4056-Basel, Switzerland

■ Syntheses of Bicyclocaprolactam Systems by the Photo-Ring-Expansion of N-Substituted Succinimides

Yuichi Kanaoka,* Haruo Okajima, Yasumaru Hatanaka, and Masanao Terashima

*Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-ku, Sapporo, Hokkaido 060-0812, Japan

Abstract

Synthetic application of the photo-ring-expansion was studied with bicycle N-substituted succinimides and a variety of bicyclocaprolactams were photochemically synthesized with retention of their endo and exo configurations.

■ Formation of Pyrrole Derivatives upon Rearrangement of 1H-1,2-Diazepines in the Presence of Fe₂(CO)₉

Francois Bellamy, Jean-Luc Schuppiser, and Jacques Streith*

*Ecole Nationale Supérieure de Chimie de Mulhouse, Université de Haute Alsace, 3, Rue Alfred Werner 68093 Mulhouse Cedez, France

Abstract

On treatment with Fe₂(CO)₉ N-arylsulfonyl-1H-1,2-diazepines 1 yield, in addition to iron tricarbonyl complexes 2, isomeric pyrrole derivatives 3. Vinylnitrenes 6, stabilized by iron tricarbonyl moieties, are postulated as the most likely reaction intermediates.

■ Photolytic Removal of a 4-Pyridyl-(t-butyl-amino-carbonyl)methyl Auxiliary Group from the Amide Nitrogen of a Four Component Condensation Product

Peter Bukall and Ivar Ugi*

*Organisch-Chemisches Institut, Technische Universität München, Lichtenbergstrasse 4, D-8046 Garching, Germany

Abstract

As a model for peptide syntheses the cleavability of the C-N bond in the four-component condensation (4 CC) product (V) of 4-pyridinecarboxaldehyde with t-butyl isocyanide, phenylacetic acid and benzylamine was studied; it was found that (V) yields N-(benzyl)phenylacetamide on photolysis.

■ Insect Antifeedant Sesquiterpene Lactones from Schkuhria pinnata: The Direct Obtention of Pure Compounds Using Reverse-phase Preparative Liquid Chromatogrphy

Michael J. Pettei, Iwao Miura, Isao Kubo, and Koji Nakanishi*

*Department of Chemistry, Columbia University, Havemeyer Hall, New York, NY 10027, U.S.A.

Abstract

The structure of two germacranolides isolated from the East and West African plant Schkuhria pinnata have been determined by spectroscopic and chemical methods to be 1 (schkuhrin-I) and 3 (schkuhrin-II). These compounds were isolated in pure form directly from the crude aqueous methanol extract of whole plant in gram-scale by reverse-phase prep-LC. They exhibit antifeedant activity against the African army worm (Spodoptera exempta) and the Mexican bean beetle, (Epilancha varivestes), antimicrobial activity against some Gram-positive bacteria and in vivo cytotoxicity (KB test) at the level of 5.5 μg/ml.

■ Thallium in Organic Synthesis. 54. Reactions of Reissert Compounds with Thallium (III) Nitrate (TTN)

Edward C. Taylor,* Ignatius J. Turchi, and Alexander Mckillop

*Department of Chemistry, Princeton University , Princeton, New Jersey 08544, U.S.A.

Abstract

Treatment of the Reissert compounds derived from substituted quinolines with thallium (III) nitrate (TTN) results either in ring contraction to dihydroindole derivatives or oxidative debenzoylation and formation of 2-cyanoquinolines, depending on the nature and postion of the substituent groups in the aromatic ring. Reissert compounds derived from isoquinolines give tetrahydroisoquinoline derivatives under the same conditions.

■ A Flexible New Synthesis of Benzo-1,3-dioxan-4-ones

Lester A. Mitscher,* Howard Eugene Gracey, George W. Clark, III, Daniel Flynn, Ted A. Baer, Shoji Omoto, Gregory Pinkleman, and Roberta Loeffler

*Department of Medicinal Chemistry, The University of Kansas, Lawrence, Kansas 66045, U.S.A.

■ New Synthetic S-Adenosyl-homocysteine Analogues with Oncostatic and Antiviral Activity

Marc Vuilhorgne, Pierre Blanchard, Charles J.R. Hedgecock, Francoise Lawrence, Malka Robert-Gero, and Edgar Lederer*

*Institut de Chimie des Substtances Naturelles, C. N. R. S., 91190 Gif-sur-Yvette, France

Abstract

Description of the synthesis of 16 new nucleosides and their activity as inhibitors of transformation of chick embryo fibroblasts by Rous Sarcoma Virus and, in vitro, of tRNA methylases and protein methylase I; the relation between chemical structure and biological activity is discussed.

■ 175 Years of Isoquinoline Drugs

Arnold Brossi*

*Laboratory of Chemistry, NIAMDD, NIH Bethesda, Maryland 20014, U.S.A.

Abstract

Morphine was isolated 175 years ago. At the occasion of this event it seemes appropriate to review isoquinoline drugs in general and to present some recent discoveries in this field. The following examples have been chosen for this purpose: 3-Deoxymorphines as analgesics, the bronchodilator trimetoquinol, the anthelmintic praziquantel and the discovery of “mammalian TIQ alkaloids” in the urine of Parkinsonian patients.

■ 2,3-Dihydro-1,4-diazepines 1973-1977

Douglas Lloyd* and Hamish McNab

*Department of Chemistry, Puredie Building, University of St. Andrews, St. Andrews, Fife, Scotland, U.K.

Abstract

The chemistry of 2,3-dihydro-1,4-diazepines and their salts as recorded in the literature 1973-1977 (with a few references from 1978) is discussed under the headings:
Introduction
Preparation of Dihydrodiazepines
Structure and Spectra
Reactions with Electrophiles
Reactions with Nucleophiles
Rearrangement Reactions
Electrochemical Reduction

■ The Use of Thiacyclophanes to Prepare Novel Conjugated Aromatic Compounds

Reginald H. Mitchell*

*Department of Chemistry, University of Victoria, Victoria, BC V8W 3V6, Canada

Abstract

Dithia[3.3]cyclophanes are easily ring contracted to cyclophanes containing a thia-substituent on the bridge. This substituent can then be eliminated to give a conjugated aromatic system. This article gives a survey of the use of this sequence to prepare novel systems.

■ Recent Progress in the Chemistry of Phenanthroinodolizidine Alkaloids

Tuticorin R. Govindachari* and Narayanaiyer Viswanathan

*CIBA-GEIGY Research Centre, Goregaon Bombay 400063, India

■ Carbon-13 NMR Study of Saccharides

Hiroshi Sugiyama*

*Chemical Research Institute of Non-Aqueous Solutions, Tohoku University, Katahira, Aoba-ku, Sendai 980-8577, Japan

■ Heterocycles Derived from 1,3,2-Dioxaphospholenes

Fausto Ramirez,* Hiroshi Okazaki, and James F. Marecek

*Department of Chemistry, State University of New York, Stony Brook, New York 11794-3400, U.S.A.

■ Heterocyclic Constituents of Meat Aroma

Günther Ohloff* and Ivon Flament

*Firmenich, Research Laboratories, CH-1211, Geneva 8, Switzerland

■ The Detection and Properties of Thiirenes

Maunel Torres, Elizabeth M. Lown, and Otto P. Strausz*

*Department of Chemistry, The University of Alberta, Calgary, Alberta, T2N, 1N4, Canada