HETEROCYCLES

■ The Equilibria and Reaction Rates of Nicotinamide-adenine-dinucleotide and Related Compounds with Cyanide Ion

Jan Vanvroeckhoven,* Jozef Lepoivre, and Frank Alderweireldet

*Labratory of Organic Chemistry, University of Antwerp (RUCA), Groenenborgerlaan 171, B-2020 Antwerp, Belgium

Abstract

Rate and equilibrium constants for addition of cyanide ion to a series of pyridinium salts have been measured photometrically in aqueous solution at different ionic strenght within the pH interval 10 - 13. All the adducts were isolated and characterized by N.M.R. spectroscopy and Mass spectrometry. From the thermodynamic quantities it was shown that the effects of pyridine 1- and 3-substituents on the cyanide affinity are independent of each other. This means that by 1-benzyl-pyridiniumsalts one can predict the reactivity of these pyridine derivative as coenzyme analogue.

■ The Reaction of (E,E)-1,4-Dibenzoyl-1,3-butadiene with o-Phenylenediamine

Howard D. Perlmutter and Richard B. Trattner*

*Department of Chemical Engineering and Chenistry, New Jersey Institute of Technology, 323 High Street, Newark, New Jersey 07102, U.S.A.

■ Synthesis of Some Pyrido-, Thieno-, and Furo-1,2-diazepines: Novel Heterocyclic Ring Systems

Takashi Tsuchiya,* Michiko Enkaku, and Hiroyuki Sawanishi

*School of Pharmacy, Hokuriku University, 3-Ho, Kanagawa machi, Kanazawa 920-1181, Japan

Abstract

The novel heterocyclic ring systems, pyrido-, thieno-, and furo-1H-1,2-diazepines (4a-f), are prepared from the corresponding parent fused pyridines (1) via the N-iminopyridinium ylides (2), and are converted to their 3H-isomers (5).

■ Syntheses of (±)-Dihydrolycoricidines from the Common Intermediate to Ethanophenanthridine Alkaloids

Kimiaki Isobe, Jun-ichi Taga, and Yoshisuke Tsuda*

*School of Pharmacy, Hokuriku University, 3-Ho, Kanagawa machi, Kanazawa 920-1181, Japan

Abstract

The common intermediate (6) to 11-oxygenated ethanophenanthridine alkaloids was converted in a stereospecific manner to the lactam-diacetate (12), from which the carboxylic function was selectively removed by alkaline hydrolysis and photolysis of the hydrolysate furnishing cis- and trans-(+)-dihydrolycoricidines, (15) and (16). This method, photoremoval of a carboxylic group via the corresponding anion, was shown to be a useful tool by several model experiments.

■ ¹H-NMR Spectral Evidences from the Double-chair Comformation of the 9-Azabicyclo[3.3.1]nonane-3,7-dione System

Takefumi Momose* and Shohgo Atarashi

*Faculty of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Toyonaka, Osaka 560-0043, Japan

Abstract

N-Benzenesulfonyl-9-azabicyclo[3.3.1]nonane-3,7-dione was synthesized, and its conformation was shown to be of a double-chair form by ¹H-nmr spectrum evidences.

■ On the Reaction Mechanism of Photo-oxidative Cyclization of Morusin

Taro Nomura* and Toshio Fukai

*School of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan

Abstract

In the present paper three possible mechanisms of the photo-oxidative cyclization of morusin (I) to morusin hydroperoxide (II) are discussed being based on the several experimental results obtained here. The following mechanisms are suggested: I in the ground state interacts with oxygen to form a contact charge transfer complex, and gave on irradiation an excited charge transfer state that may lead to reactive species such as free radicals, finally giving the photoreaction product (II). This reaction mechanism is drawn in Chart 6.

■ The Biosynthesis of Vindoline Using Cell Free Extracts from Mature Catharanthus roseus Plants

Kenneth L. Stuart, James P. Kutney,* Toshio Honda, Norman G. Lewis, and Brian R. Worth

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

Abstract

Cell free extracts from mature Catharanthus roseus plants can biosynthesise vindoline (7, R = Ac) utilising ¹⁴C-tryptamine, secologanin (6) and S-adenosyl-methionine (methyl-¹⁴C).

■ Alternative Methods for the Alkylation of Isoquinoline Reissert Compounds

Jerry W. Skiles and Michael P. Cava*

*Department of Chemistry, University of Pennsylvania, 231 South 34th Street Philadelphia, PA 19104-6323, U.S.A.

Abstract

A comparative study was made of the alkylation of five representative isoquinoline-type Reissert compounds (1 - 5) with both benzyl chloride and o-nitrobenzyl chloride, using three different base-solvent systems: (A) lithium diisopropylamide in THF/HMpA, (B) KOH with benzene and dicyclohexyl-18-crown-6, and (C) 50% aqueous NaOH with benzene or acetonitrile and cetrimonium bromide. Systems (B) and (C) were clearly the best, the latter being especially advantageous.

■ Demethylation of Papaverinol with Sulfuric Acid

Luis Castedo,* José M. Saá, Rafael Suau, and Carmen Villaverde

*Departmento de Química Orgánica, Facultad de Química y Sección de Alcaloides, Universidad de Santiago de Compostela, E-15706, Santiago de Compostela, Spain

Abstract

Structure 3 is definitively established instead of the reported 2 for the monodemethylated compound obtained by treatment of papaverinol (1) with 90% sulfuric acid as shown by C-13 nmr spectroscopy. A tentative mechanism is proposed for the reaction.

■ Neorhusflavanone, a New Biflavanone from Wax-tree

Fa-ching Chen,* Yuh-meei Lin, and Yuh-chi Lin

*Department of Chemistry, National Taiwan University, Roosevelt Road Section 4, Taipei 106, Taiwan, R.O.C.

Abstract

Neorhusflavanone was identified as 4’,4’’’,5,5’’,7,7’’-hexahydroxy-8,8’’-biflavanone, i.e. 8,8’’-binaringenin, by i., u.v., n.m.r., and mass spectroscopic comparison with the synthetic compound, and conversion into cupressuflavone derivatives using NBS as dehydrogenating agent.

■ Hydrolysis of the Benzoate of 3-Hydroxy-3-(1-isoquinolyl)oxindole

Frank D. Popp,* Raymond F. Watts, and Robert M. Piccirilli

*Department of Chemistry, University of Missouri-Kansas City, Kansas City, Missouri 64110, U.S.A.

Abstract

The hydrolysis of the title compound gives 2-aminophenyl- 1-isoquinolylcarbino1 as the major product.

■ A Simple Synthesis of 1,3-Benzoxazin-4-one Derivatives

Tetsuji Kametani,* Chu Van Loc, Masataka Ihara, and Keiichiro Fukumoto

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

Abstract

Treatment of salicyl chloride (2), prepared from salicylic acid and oxalyl chloride, with isoquinoline (1) gave the isoquinolobenzoxazinone (3). Reaction of (2) with 3,4-dihydro-6,7-dimethoxy-1-methylisoquinoline (4), 3,4-dihydro-6-methoxy-β-carboline (6), and 3,4-dihydro-6-methyl-β-carboline (8) afforded the corresponding 1,3-benzoxazin-4-one derivatives (5) , (7) , and (9) respectively.

■ Isomerisations and Cyclisations in Blue Pigments

Michèle Bois-Choussy and Michel Barbier*

*Institut des Chimie des Substances Naturelles, C.N.R.S., 1 avenue de la Terrasse, Bat. 27, 91198 Gif-sur-Yvette Cedex, France

Abstract

This article provides a survey of the isomerisations and cyclisations occuring in bile pigments. Three types of cyclisation have been established, leading to new condensed heterocyclic systems. The neoverdins, isopterobilin, isophorcabilin and sarpedobilin are formed from such transformations.