Regular Issue

Vol. 24, No. 9, 1986

35 data found. 1 - 30 listed Next Last
Communication | Regular issue | Vol 24, No. 9, 1986, pp. 2399 - 2402
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DOI: 10.3987/R-1986-09-2399
Sulfonioindolides and Sulfoniopyrrolides

Klaus Hartke* and Dorothee Strangemann

*Institut für Pharmazeutische Chemie, Universität Marburg, Marbacher Weg 6, D-35032 Marburg/Lahn, Germany


Sulfoxides react with indoles and pyrroles in the presence of trifluoroacetic anhydride to form 3-indolylsulfonium- and 2- or 3-pyrrolylsulfoniom salts. Deprotonation gives rise to sulfonioindolides and sulfoniopyrrolides.

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Communication | Regular issue | Vol 24, No. 9, 1986, pp. 2403 - 2406
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DOI: 10.3987/R-1986-09-2403
Addition of 2(1H)-Pyridinethione to 3,4-Dihydro(2H)-pyran

Hari Babu Mareyala*

*National Chemical Laboratory, Poona-41108, India


The title reaction gave [tetrahydro-2H-pyran-2’-yl]-2-thiopyridine (5) rather than 1-tetrahydropyranyl-2-pyridine thione (6) as was earlier reported. 1

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Communication | Regular issue | Vol 24, No. 9, 1986, pp. 2407 - 2410
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DOI: 10.3987/R-1986-09-2407
One Pot Preparation of 1,3-Dimethyltetrahydroisoquinolines from Their Biosynthetic Diketo Precursors

Gerhard Bringmann* and Johannes R. Jansen

*Organisch-Chemisches Institut, Universität Münster, Orleansring 23, D-4400 Münster, Germany


Biomimetic reactions modelling the nitrogen incorporation into the monocyclic precursors 2 of naphthylisoquinoline alkaloids, using pyridoxamine (9b) are described. The condensation of 2b with 9b, or, more simply, with benzylamine, though not giving a dihydroisoquinoline 7, provides an efficient one pot synthesis of already protected 1,3-dimethyltetrahydroisoquinolines 14, by in situ reduction of the resulting isoquinolinium salts 12.

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Communication | Regular issue | Vol 24, No. 9, 1986, pp. 2411 - 2413
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DOI: 10.3987/R-1986-09-2411
Synthesis of 5,5’-Dialkoxy-2,2’-dioxazolylsulfides

Ricardo Bossio, Stefano Marcaccini,* and Robert Pepino

*CNR, Centro di Studio Sulla Chimica e la Struttura dei Composti Eterociclici e lolo Applicazioni, c/o Dipartimento di Chimica Organica "Ugo Schiff", Università di Firenze, Via Gino Capponi 9, I-50121 Firenze, Italy


Alkyl isocyanoacetates I reacted with sulfur dichloride to give the intermediate sulfides IV which on treatment with triethylamine afforded the hitherto unknown dioxazolylsulfides II.

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Communication | Regular issue | Vol 24, No. 9, 1986, pp. 2415 - 2421
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DOI: 10.3987/R-1986-09-2415
Altered Alkaloid Pattern in Dark Grown Seedlings of Catharanthus roseus. The Isolation and Characterization of 4-Desacetoxyvindoline: A Novel Indole Alkaloid and Proposed Precursor of Vindoline

John Balsevich,* Vincenzo DeLuca, and Wolf G. W. Kurz

*Plant Biothchnology Institute, National Research Council of Canada, Saskatoon, Saskatchewan, S7N, OW9, Canada


Seeds of Catharanthus roseus cv. Little Delicata were germinated in the dark which resulted in relatively high and even rates of germination. Analysis of alkaloids from the cotyledons of 6 - 9 day old dark grown seedlings led to the identification of tabersonine, 16-methoxytabersonine, and catharanthine as relatively major components while vindoline, deacetylvindoline, 4-desacetoxyvindoline and 16-hydroxytabersonine were identified as minor components. Subjecting dark grown seedlings to light led to a rapid increase in the amount of vindoline present with a concomitant decrease in the amounts of tabersonine, 16-methoxytabersonine and the minor components. The amount of catharanthine present was not greatly affected. These observations suggested that the biosynthetic pathway between tabersonine and vindoline proceeds as follows: 16-hydroxytabersonine → 16-rnethoxytabersonine → 16-methoxy-2,3-dihydro-3-hydroxytabersonine → 16-methoxy-2,3-dihydro-3-hydroxy-N(1)-methyltabersonine (i .e. desacetoxyvindoline) → deacetylvindoline → vindoline.
+ The numbering system used was as for aspidospermidine in Chemical Abstracts.

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Communication | Regular issue | Vol 24, No. 9, 1986, pp. 2423 - 2427
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DOI: 10.3987/R-1986-09-2423
The Origin of the Regioselectivities in 1,3-Dipolar Cycloaddition of Thiocarbonyl Ylides Generated from Bromo(trimethylsilylmethylthio)methyltrimethylsilane and the Related Compoundsq

Nobuyuki Imai, Hiroaki Tokiwa, Masahiro Aono, Yoshiyasu Terao, Yukio Akahori, and Kazuo Achiwa*

*Schol of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan


The regioselectivities in 1,3-dipolar cycloaddition of thiocarbonyl ylides to methyl acrylate were found to be explained by the frontier molecular orbital theory using ab initio procedures at the STO-3G level.

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Communication | Regular issue | Vol 24, No. 9, 1986, pp. 2429 - 2436
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DOI: 10.3987/R-1986-09-2429
The Astounding Reaction of Diazomethane with Dimethyl 2,3-Dicyanofumarate

Rolf Huisgen,* Abhijit Mitra, and Joaquin Rodriguez Moran

*Institut für Organische Chemie, Universität München, Karlstrasse 23, D-80333 München, Germany


The title reaction afforded the pyrazole derivatives 3 and 4 as well as the N-methyl-1,2,3-triazolecarboxylic esters 5 - 7. The poly-step sequence was clarified; the key intermediates are the 1-pyrazoline 18, the 2-pyrazoline 2, the 4H-pyrazole 12, the pyrazole 22, and methyl cyanoformate.

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Communication | Regular issue | Vol 24, No. 9, 1986, pp. 2437 - 2441
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DOI: 10.3987/R-1986-09-2437
On the Reaction of N-Vinyliminophosphoranes 3. A Novel Route to Phenyl-substituted Pyrroles by the Reaction of N-(1-Phenylvunyl)iminophosphoranes with α-Bromo Ketones

Yukio Iino, Tomoshige Kobayashi, and Makoto Nitta*

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


N-(1-Phenylvinyl)iminotriphenylphosphorane or N-(1-phenylvinyl)iminotributylphosphorane reacted with α-bromo ketones to give phenyl-substituted pyrroles via a novel C-C bond formation followed by aza-Wittig reaction.

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Communication | Regular issue | Vol 24, No. 9, 1986, pp. 2443 - 2447
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DOI: 10.3987/R-1986-09-2443
Oxidation of Cyclobutanones to γ-Butyrolactones with Hydrogen Peroxide in 2,2,2-Trifluoroethanol

Masakatsu Matsumoto* and Hisako Kobayashi

*Sagami Central Research Center, 4-4-1 Nishi-Ohnuma, Sagamihara, Kanagawa 229-0012, Japan


Cyclobutanones were selectively oxidized to yield γ-butyrolactones with hydrogen peroxide in 2,2,2-trifluoroethanol.

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Communication | Regular issue | Vol 24, No. 9, 1986, pp. 2449 - 2454
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DOI: 10.3987/R-1986-09-2449
A New Synthetic Route to 2-Deuterioadenines Substituted or Unsabustituted at the 9-Position

Tozo Fujii,* Tohru Saito, Kyoko Kizu, Hiromi Hayashibara, Yukinari Kumazawa, and Satoshi Nakajima

*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan


9-Alkyl-2-deuterioadenines (VIIIb-d) , adenosine-2-d (VIIIe), and 2’-deoxyadenosine-2-d (VIIIf) were synthesized from the 9-substituted adenines Ib-f through cyclization of the monocyclic intermediates VIb-f with formic acid-d2 or 1-(formyl-d)-2(1H)-pyridone. Hydrolysis of VIIIe, prepared through this synthetic route, with 0.5 N aqueous HCl (reflux, 2 h) gave adenine-2-d (VIIIa) in 77% yield. Unambiguous assignments of the purine ring protons in the nmr spectra of the unlabeled adenines Ia-f have been made by comparison with those of the labeled adenines VIlla-f.

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Report | Regular issue | Vol 24, No. 9, 1986, pp. 2455 - 2461
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DOI: 10.3987/R-1986-09-2455
Nitriles in Heterocyclic Synthesis: New Route fot the Synthesis of Pyridine and Pyrido[2,3-d]pyridazine Derivatives

Zaghloul El-Shahat Kandeel,* Fathy Mohamed Abdelrazek, Mohamed Hilmy Elnagdi, and Abdel Moneim El-Torgoman

*Department of Chemistry, Faculty of Science, University of Cairo, Giza, Egypt


Several new 2-cyanohydrazonomethyl pyridines and pyrido[2,3-d]pyridazine derivatives were obtained via the reaction of arylhydrazononitriles with 2-amino-1,1,3-tricyanopropene and diethyl 3-amino-2-cyanopent-2-ene-dicarboxylate.

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Report | Regular issue | Vol 24, No. 9, 1986, pp. 2463 - 2466
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DOI: 10.3987/R-1986-09-2463
The Chemistry and Synthetic Potentialities of β-Ketoanilides: Reaction of Ethyl Cyanoacetate with β-Ketoanilides

Adiba Habashi, Nadia Sobhy Ibraheim, Sherif Mourad Sherif, Hoda Zaki Shams, and Rafat Milad Mohareb*

*Department of Chemistry, Faculty of Science, Helwan University, Ain-Helwan, Cairo, Egypt


Ethyl cyanoacetate reacts with β-ketoanilides 2a-g to give the simple Knoevenagel condensation products 3a-g. The reactivity of 3a towards a variety of chemical reagents was studied to give, in most cases, polyfunctionally substituted pyridine derivatives.

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Report | Regular issue | Vol 24, No. 9, 1986, pp. 2467 - 2470
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DOI: 10.3987/R-1986-09-2467
Synthesis of Azetidine from 1-Substituted Azetidin-3-ols

Yoshihiro Nitta* and Yasuyuki Kanamori

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


From readily available 1-substituted azetidin-3-ols, azetidine was prepared in high yield by removal of the hydroxyl group and N-substituents.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2471 - 2477
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DOI: 10.3987/R-1986-09-2471
Reaction of Rotenoids with Hydrazine

Ivanka Kostova,* Nadejda Spassovska, Lilyana Maneva, Evgeni Golovinsky, and Iliya Ognyanov

*Centre of Ohyrochemistry, Institute of Organic Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria


The preparation and the structure of the rotenoid hydrazones is discussed. The normal hydrazones, prepared in acidic medium, retain the original rotenoid skeleton (6aβ,12aβ,5’β). The so-called isohydrazones, obtained in alkaline medium, are derivatives of the [1]benzopyrano[3,4-c]pyrazole ring system with cis B/C-rings juncture.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2479 - 2485
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DOI: 10.3987/R-1986-09-2479
Studies in Spiroheterocycles: Part IX: A New Elegant Synthesis and Reactions of Some Novel Fluorine-containing Spiro[3H-indole-3,2’-tetrahydro-1,3-thiazine]-2,4’(1H)-diones

Krishna C. Joshi,* Anshu Dandia, and Nidhal Ahmed

*Department of Chemistry, University of Rajasthan, Jaipur 302 004, India


A number of novel fluorine-containing spiro[3H-indole-3,2’-tetrahydro-1,3-thiazine]-2,4’(1H)-diones have been synthesized by an elegant one-step procedure involving the condensation of fluorine-containing indole-2,3-diones, fluorinated aromatic amines and 3-mercaptopropanoic acid without isolating the intermediate isatin-3-anils. The spiro compounds have been further subjected to acetylation, chloroacetylation and Mannich reactions. N-Acetylated spiro compound was simultaneously synthesized from 1-acetylindole-2,3-dione and aniline. The structures of all the compounds have been confirmed on the basis of elemental analyses, ir, 1H nmr, 13C nmr, 19F nmr and mass spectral studies.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2487 - 2491
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DOI: 10.3987/R-1986-09-2487
Synthesis of a Cimetidine Analogue

József Heiszman, Kálmán Harsányi, and László Töke*

*Department of Organic Chemical Technology, Technical University of Budapest, H-1521 Budapest, Gellért tér 4, Hungary


2-Hydroxymethyl-4-methylimidazole(2a) and 2,5-bis(hydroxymethyl)-4-methylimidazole(3a) have been synthesized and characterized. No reaction on the hydroxymethyl moieties in position 2 of these compounds could be observed with cysteamine under usual reaction conditions. The hydroxymethyl group in position 5 of compound 3a does react with cysteamine to give an intermediate leading to 3b and to cimetidine analogue 3c.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2493 - 2506
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DOI: 10.3987/R-1986-09-2493
The Reaction of Quinazolin-4-ones with Organo-metalic Agents — A Presistent Preference for Ring Rupture over Cyclization

Darshan Ranganathan,* Firdous Farooqui, Sanjiv Mehrotra, and Krishnan Kesavan

*Department of Chemistry, Indian Institute of Technology, Kanpur 208016, India


A range of 3-substituted quinazolin-4-ones whose conjugate bases can undergo intramolecular cyclization to tricyclic systems, have been prepared (Scheme 2). The reaction of these with a variety of organolithium agents gave products arising from reagent addition to the quinazolin-4-one 1,2 bond, although experimental results tended to demonstrate that the desired conjugate bases existed in equilibrium with the tricyclic systems. The acetyl salt of 1a with NaH gave product 3c from ring fragmentation. The imidazoquinazoline 8, the parent of which is markedly antihypotensive, resulted from endeavours to prepare a prototype of the desired tricyclic system by an alternate route. Most compounds studied have more than one site for reactivity against the reagents used. The experimental results clearly highlight an overwhelming preference for addition to quinazolin-4-one 1,2 bond.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2507 - 2510
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DOI: 10.3987/R-1986-09-2507
Synthesis of 2,2’-Ethylene-bis(1,2-dihydrobenzo[h]-3H-4,2-benzoxazine) and 3,3’-Ethylene-bis(3,4-dihydrobenzo[h]-2H-1,3-benzoxazine) and Assignation of Their 1H-NMR Spectra Using the LAOCN3 Computer Program

Augusto Rivera,* Edgar Ospina, Armando Sánchez, and Pedro Joseph-Nathan

*Departamento de Química, Universidad Nacional de Colombia, Ciudad Universitaria, Bogotá, Colombia


Two new bis-benzoxazines, 2,2’-ethylene-bis(1,2-dihydrobenzo[h]-3H-4,2-benzoxazine) (I) and 3,3’-ethylene-bis(3,4-dihydrobenzo[h]-2H-1,3-benzoxazine) (II) were obtained by the Mannich reaction of β- and α-naphthol with formaldehyde and ethylendiamine. Their 1H-nmr spectra were simulated and interpretated using the LAOCN3 computer program.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2511 - 2517
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DOI: 10.3987/R-1986-09-2511
Photolysis of Cyclic Acetals of Aryl Benzoylacetates as the Key Step in a New Synthesis of Flavones

Hermenegildo García, Sara Iborra, Miguel A. Miranda,* and Jaime Primo

*Departamento de Química Orgánica, Universidad de Valencia, Calle Dr. Moliner, 50, E-46100 Burjassot (Valencia), Spain


Although the yields found for the photo-Fries rearrangement of the aryl benzoylacetates 1 are poor, blocking of the carbonyl group, as in the related acetal derivatives 3, results in a substantial preparative improvement. Thus, the o-hydroxydibenzoylmethanes 2 are obtained from 1 with an average yield of 18%, while the corresponding acetals 4 are obtained from 3 with an average yield of 58%. Compounds 4 are efficiently converted into flavones 8 by means of wet silica gel, through hydrolysis of the acetal moiety and subsequent cyclization of the resulting o-hydroxydibenzoylmethanes 2.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2519 - 2538
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DOI: 10.3987/R-1986-09-2519
AB Initio Quantum-chemical Study on the Influence of Methyl Substitution on the Redox Behaviour of 1,4-Dihydronicotinamides. Part 1: Unperturbed Molecules and Perturbations towards a Possible Transition State

Jan Bossaerts, Frank C. Alderweireldt,* and Paul Geerlings

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


The experimental31 reactivity sequence of a series of methyl substituted 1-(2,6-dichlorobenzyl)-1,4-dihydronicotinamides is compared with the results of an ab-initio STO-3G quantum-chemical calculations on the corresponding 1-methyl compounds. The molecules were studied both in approximative equilibrium geometry and geometries distorted towards a possible transition state. The theoretical results are successfully confronted with the experimental data.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2539 - 2543
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DOI: 10.3987/R-1986-09-2539
A New Synthesis of Optically Active 2-Methoxycarbonyl-4-azetidinone from L-Azetidine-2-carboxylic Acid: Utility of Ruthenium Tetroxide Oxidation

Ken-ichi Tanaka,* Shigeyuki Yoshifuji, and Yoshihiro Nitta

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


A first transformation of L-azetidine-2-carboxylic acid (1) into optically active monocyclic N-unsubstituted β-lactam, (2S)-2-methoxycarbonyl-4-azetidinone (6), has been developed via ruthenium tetroxide (RuO4) oxidation process.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2545 - 2552
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DOI: 10.3987/R-1986-09-2545
The Electrophilic Substitution of Heteroaromatic Compounds. Part 53. The Experimental Orientation in the Electrophilic Substitution of 1-Phenylpyridinium Cations, and a Theretical Treatment of Electrophilic Substitution Orientations in N-Phenylheterocycles

Alan R. Katritzky,* Hassan M. Faid-Allah, Hudson Luce, Mati Karelson, and George P. Ford

*Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, P. O. Box 117200, Gainesville, FL 32611-7200, U.S.A.


Nitration, sulfonation and bromination of the title compound occur in the meta position of the 1-phenyl group. This meta substitution, and the para substitution previously observed for other N-phenylheterocycles, cannot be explained by static reactivity indices. However, a MNDO analysis, taking account of the near degeneracy of the two top HOMO’s, and using experimentally probable interannular anglee, allows rationalization of the orientations observed.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2553 - 2556
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DOI: 10.3987/R-1986-09-2553
The Reaction of β-Aminoalcohols with 1,2-Benzenedicarboxaldehyde — A Correction

William A. Metz and Peter J. Wepplo*

*Agricultural Producsts Research Division Attn: Library, American Cyanamid Company, P. O. Box 400, Clarksville Raod, Princeton, NJ 08543-0400, U.S.A.


The structure of the compound obtained from the reaction of 2-amino-2-methyl-1-propanol with 1,2-benzenedicarboxaldehyde is revised.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2557 - 2562
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DOI: 10.3987/R-1986-09-2557
Oxidation of 1-Benzoylpyrrole and 1-Aroylindoles by Palladium Acetate

Toshio Itahara*

*Department of Bioengineering, Faculty of Engineering, Kagoshima University, Korimoto, Kagoshima 890-0065, Japan


Oxidation of 1-benzoylpyrrole and 1-aroylindoles by palladium acetate in acetic acid gave the corresponding ring-closed products and dimerized compounds.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2563 - 2570
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DOI: 10.3987/R-1986-09-2563
Ylide-induced Ylide Formation: A Thermal Reaction and a Double Cycloaddition Reaction of [1,2,4]Triazolo[1,5-a]pyridinium Ylides

Mikio Hori,* Tadashi Kataoka, Hiroshi Shimizu, Eiji Imai, Masaharu Yokomoto, Kiyomi Tanaka, Kazuhiko Kimura, and Yoshinobu Hashimoto

*Department of Pharmacognosy, Gifu College of Pharmacy, 6-1 Mitahora-higashi 5-chome, Gifu 502-8585, Japan


1-Alkyl[1,2,4]triazolo[1,5-a]pyridinium salts (2) were synthesized by the reaction of [1,2,4]triazolo[1,5-a]pyridine (1) with alkyl halides in dry acetone under reflux. The thermal reaction of ylides (3) gave 2-cyanamidopyridines (4) or 2-oxazolylpyridine (5). The reaction of ylides (3) with methyl propiolate or dimethyl acetylenedicarboxylate resulted in the formation of pyrazolo[1,5-a]pyridine derivatives via a double 1,3-dipolar cycloaddition reaction.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2571 - 2579
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DOI: 10.3987/R-1986-09-2571
Electron Impact Mass Spectrometry of Substituted 3,4,5,6-Tetrahydro-1,4-oxazin-2-one Derivatives

Vassil St. Georgiev,* David C. Coomber, and George B. Mullen

*Department of Organic Chemistry, Pharmaceutical Division, Pennwalt Corporation, Rochester, New York 14623, U.S.A.


The electron impact mass spectrometry of a series of novel and biologically active substituted 3,4,5,6-tetrahydro-1,4-oxazin-2-one derivatives is described. The mass spectral fragmentation pattern of spiro[3,4,5,6-tetrahydro-1,4-oxazin-2-one-6,2’-tricyclo[,7]decane] (2), a novel adamantane-spiro-heterocyolic system has also been investigated. The fragmentation pattarn of all compounds studied was found to be heavily influenced by the nature of their substituents.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2581 - 2586
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DOI: 10.3987/R-1986-09-2581
Stannous Chloride Reduction of α,β-Unsaturated Nitroalkenes: A Direct Synthesis of 2-Aryl-2H-1-benzopyran-3(4H)-one Oximes

Rajender S. Varma, Manju Verma, Yuan-Zhu Gai, and George W. Kabalka*

*Department of Chemistry, University of Tennessee, Knoxville, Knoxville, TN 37996, U.S.A.


Stannous chloride, in acetone, readily reduced the α,β-unsaturated nitroalkenes to the corresponding oximes at room temperature. A series of 2-aryl-3-chromanone oximes were obtained via the reduction of 3-nitrochromenes.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2587 - 2592
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DOI: 10.3987/R-1986-09-2587
Pseudoesters and Derivatives. XXIV. 1,3-Dipolar Cycloaddition of Diazomethane to 5-Methoxyfuran-2(5H)-ones

Francisco Fariña,* M. Victoria Martín, and Férix Sánchez

*Instituto de Química Orgánica General, C. S. I. C., Calle Juan de Cierva, 3, 28006 Madrid, Spain


Cycloaddition of diazomethane to 5-methoxyfuran-2(5H)-ones ( 1) occurs in a practically regiospecific manner to give the expected adducts. The cycloadducts are mixtures of the furopyrazoline derivatives 2 and 3 epimeric at C-4, with the exception of those of 1f and 1h that afford only one detectable adduct (2f and 2h) in each case. The regio- and stereochemistry of the adducts follows from the 1H-NMR data. The regiochemistry of the cycloaddition is also corroborated by chemical correlations. Pyrolysis of the epimeric mixtures 2a/3a, 2b/3b and 2d/3d affords the 4-methyl substituted furanones 1c, 1i and 1j in good yields.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2593 - 2601
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DOI: 10.3987/R-1986-09-2593
Structures of Cachineside III, IV, and V, Iridoid Glucosides from Campsis chinensis Voss.

Yasuhiro Imakura and Shigeru Kobayashi*

*Faculty of Pharmaceutical Sciences, University of Tokushima, Sho-machi, Tokushima 770-8505, Japan


Three new iridoid glucosides, cachineside III, IV and V have been isolated from the dried leaves of Campsis Chinensis Voss., and established to have the structures 8, 9 and 10, respectively, on the basis of spectral data and chemical transformations.

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Paper | Regular issue | Vol 24, No. 9, 1986, pp. 2603 - 2610
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DOI: 10.3987/R-1986-09-2603
Structures of Kuwanons Y and Z, Two New Stilbene Derivatives from the Cultivated Mulberry Tree (Morus alba L.)

Yoshio Hano, Hiromi Tsubura, and Taro Nomura*

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


Two novel stilbene derivatives named kuwanons Y and Z were isolated from the acetone extract of the reddish violet powder (lenticel) from the surface of the root bark of cultivated mulberry tree (Ichinose, a cultivated variety of Morus alba L.). The structures of kuwanons Y and Z were shown to be 1 and 2, respectively, on the basis of spectral and chemical evidence. Kuwanon Y is regarded biogenetically as a Diels-Alder type adduct of a chalcone derivative and a dehydroprenylstilbene derivative, while kuwanon Z as a variation of a Diels-Alder type adduct.

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35 data found. 1 - 30 listed Next Last