Regular Issue

Vol. 36, No. 8, 1993

26 data found. 1 - 26 listed
Communication | Regular issue | Vol 36, No. 8, 1993, pp. 1715 - 1720
Published online:
DOI: 10.3987/COM-93-6389
Synthesis of New Molecules Adopting a Unique Sigmoid Conformation with Stacked Aromatic Rings in the Crystalline State

Yoshimitsu Nagao,* Shigeki Sano, Satoshi Nakagawa, Masanobu Suzuki, Motoo Shiro, Masaru Kido, and Takao Nishi

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


Synthesis of new molecules adopting a unique sigmoid conformation in the crystalline state has been achieved. Conformational analysis of these molecules is investigated by utilizing X-ray and 1H nmr analyses.

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Communication | Regular issue | Vol 36, No. 8, 1993, pp. 1721 - 1724
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DOI: 10.3987/COM-93-6393
Photocycloaddition of Cytosine and 2’-Deoxycytidines to 2,3-Dimethyl-2-butene

Naoki Haga and Haruo Ogura*

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


Irradiation of far-uv light of cytosine, 2’-deoxycytidine and its N-acetyl-3’,5’-di-O-acetyl derivative in the presence of 2,3-dimethyl-2-butene in acetone yielded the corresponding cyclobutane photoadducts.

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Communication | Regular issue | Vol 36, No. 8, 1993, pp. 1725 - 1728
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DOI: 10.3987/COM-93-6397
Synthesis of Methyl 2-Cyano-(1,2-dimethylcyclohepta[b]pyrrol-6-ylidene)acetate. A Steric Effect to Accelerate the Geometrical Isomerism of the Exocyclic C=C Bond of Heterocycle-fused Heptafulvenes

Yukari Ikeda, Bing Zhu Yin, Nobuo Kato, Akira Mori,* and Hitoshi Takeshita*

*Instituete of Advanced Material Study, Kyushu University, 6-1, Kasuga-koen, Kasuga 816-8580, Japan


The rotational barriers of the exocyclic C=C bonds of heptafulvenes condensed with furan, pyrrole, and thiophene rings were largely dependent on the steric repulsion around the exocyclic C=C bonds; newly synthesized methyl 2-cyano-(1,2-dimethylcyclohepta[b]pyrrol-6-ylidene)acetate and its furanylidene analogue revealed higher energy barriers than the corresponding methyl 2-cyano-(1,2-dimethylcyclohepta[b]pyrrol-8-ylidene)acetate and the furan derivatives.

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Communication | Regular issue | Vol 36, No. 8, 1993, pp. 1729 - 1734
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DOI: 10.3987/COM-93-6398
Mild and Chemoselective Cleavage of p-Nitrobenzyl Esters and p-Nitrobenzyloxycarbonyl Amines with Zinc Dust

Toshio Kumagai,* Takao Abe, Yukari Fujimoto, Takaaki Hayashi, Yoshinori Inoue, and Yoshimitsu Nagao*

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


p-Nitrobenzyl esters and p-nitrobenzyloxycarbonyl amines have been efficiently deprotected by treatment with zinc dust in THF - 0.35 M phosphate buffer solution (pH 6) to obtain the parent carboxylic acids and amines. Olefinic bond, S-N bond, and diphenylmethyl- and benzyloxycarbonylamino groups are intact under the deprotection conditions.

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Communication | Regular issue | Vol 36, No. 8, 1993, pp. 1735 - 1738
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DOI: 10.3987/COM-93-6402
Functionalization at C-3a of Tryptophan Derived Hexahydropyrrolo[2,3-b]indoles

Milan Bruncko, David Crich,* and Raghu Samy

*University of Illinois at Chicago, Department of Chemistry (M/C 111), 801 West Taylor St. , Chicago, IL 60607-7061, U.S.A.


Under free radical conditions the cyclic tryptophan tautomer (1) suffers oxidation at the benzylic position (C-3a) giving, with NBS, the 3a-bromo derivative and, with CAN, the 3a-hydroxy and 3a-nitrato derivatives. In contrast, under electrophilic conditions, aromatic bromination with NBS occurs cleanly at C-5

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Communication | Regular issue | Vol 36, No. 8, 1993, pp. 1739 - 1742
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DOI: 10.3987/COM-93-6408
An Interesting Chemoselectivity in Palladation of Aromatic Bromides

Yuusaku Yokoyama, Mitsuru Takashima, Chitose Higaki, Kazuko Shidori, Shoko Moriguchi, Chizuru Ando, and Yasuoki Murakami*

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


The reaction of various aromatic bromides with ethyl acrylate in the presence of stoichiometric amount of Pd(OAc)2 gave the vinylated products without affecting the carbon-bromine bond.

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Communication | Regular issue | Vol 36, No. 8, 1993, pp. 1743 - 1746
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DOI: 10.3987/COM-93-6414
The First Direct Synthesis of Isoflavans via α-Alkylation of Phenylacetates

Marietjie Versteeg, Barend C. B. Bezuidenhoudt,* and Daneel Ferreira*

*Department of Chemistry, University of Orange Free State, P.O. Box 339, Bleoemfontien, 9300, South Africa


Deprotonation of phenylacetates and quenching of the enolates with benzylic electrophiles, afford 2,3-diarylpropanoates which serve as precursors to isoflavans following consecutive reduction and cyclization steps.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1747 - 1762
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DOI: 10.3987/COM-92-6327
Functionalization of the Dihydrothiazine Ring of Cephem Sulfones

Marco Alpegiani, Pierluigi Bissolino, Daniela Borghi, Pietro Sbraletta, Roberto Tonani, and Ettore Perrone*

*Pharmacia Farmitalia Carlo Erba R&D, 20014 Nerviano, Milano, Italy


Functionalization of the dihydrothiazine ring of cephem esters and 4-ketones was studied at the sulfone oxidation level. On the esters, alkylation and Michael addition gave 4β- and 2α,4β-substituted products. On the ketones, electrophilic insertion of carbon, halo, oxygen and sulfur substituents was achieved with acceptable selectivity at 2α. Nucleophilic sulfenylation and acyloxylation was successful on 2-bromocephem ketones, themselves electrophilic bromination products. Noticeable events included shift of the 3-cephem double bond and epimerization at C-2. Configurations and ring conformation were evinced by nmr studies. Several compounds were potent inhibitors of human leukocyte elastase.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1763 - 1769
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DOI: 10.3987/COM-93-6336
β-Amino Alcohol-N-oxides as Precursors of Chiral Oxazolidines: Synthesis of (R)-(-)-Cryptostyline I

Anny-Claude Carbonnelle, Vincent Gott, and Georges Roussi*

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


The access to chiral oxazolotetrahydroquinoline by base deprotonation of 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline-N-oxide, allowed the synthesis of (R)-(-)-cryptostyline I.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1771 - 1774
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DOI: 10.3987/COM-93-6342
(-)-Jaboromagellonine: New Withanolide from Seeds of Jaborosa magellanica

Claudia Cárcamo,Víctor Fajardo*, and Emilia Tojo

*Universidad de Magallanes, Facultad de Ciencias, Departamento de Ciencias y de Recursos Naturales, Punta Arenas, Chile


From seeds of Jaborosa magellanica (Griseb.) Dusén (Solanaceae), a new withanolide was isolated and studied by nmr and mass spectroscopy.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1775 - 1781
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DOI: 10.3987/COM-93-6344
A One Step Synthesis of Benzimidazo[2,1-c][1,2,4]triazole Derivatives Using Hydrazonoyl Halides

Hamdi M. Hassaneen,* Ahmad S. Shawali, Mary S. Khalil, Tayseer A. Abdallah, and Mohamed S. Algharib

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


A synthesis of benzimidazo[2,1-c][1,2,4]triazole derivatives (9) has been accomplished from the reaction of hydrazonoyl halides (1) with 2-methylmercaptobenzimidazole (6) in chloroform in the presence of triethylamine.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1783 - 1789
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DOI: 10.3987/COM-93-6348
A Facile One-Pot Preparation of 2,3-Dihydro-1,4-benzodithiins and 2,3-Dihydro-1,4-benzoxathiins

Hiroyuki Tani,* Shunsuke Irie, Kazunori Masumoto, and Noboru Ono*

*Advanced Instrumentation Center for Chemical Analysis, Ehime University,Bunkyo-cho 2-5, Matsuyama 790-8577, Japan


2,3-Dihydro-1,4-benzodithiines and 2,3-dihydro-1,4-benzoxathiines were prepared in good yields by a one-pot procedure from the reaction of cyclohexanone derivatives with ethane-1,2-dithiol or 2-mercaptoethanol using N-bromosuccinimide in dichloromethane at 0 °C

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1791 - 1794
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DOI: 10.3987/COM-93-6356
(S)-1,3-Dimethyl-3-hydroxy-5-methoxyoxindole: By-Product in the Synthesis of Physostigmine

Qian-sheng Yu, Yi-qun Li, Wei-ming Luo, and Arnold Brossi*

*Department of Chemistry, Georgetown University, Washington DC 20057, and Scientist Emeritus NIH, U.S.A.


(S)-1,3-Dimethyl-3-hydroxy-5-methoxyoxindole (4) was obtained as a by-product in the asymmetric alkylation of oxindole (1) with methyl chloroacetate in the presence of N-[(4-trifluoromethyl)benzyl]cinchonium bromide. Its structure was established by spectral data. Optically active (4) of (S)-configuration was obtained from oxindole (1) on air oxidation in the presence of the chiral catalyst N-[(4-trifluoromethyl)benzyl]cinchonium bromide.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1795 - 1802
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DOI: 10.3987/COM-93-6363
The Optimization of the Diels-Alder Reactions of 2,5-Disubstituted Furan Derivatives with Functionalized Chains. Synthetic Applications

Benito Alcaide, Cristina Biurrun, and Joaquín Plumet*

*Universidad Complutense , Facultad de Química, Departamento de Química Orgánica,E-28040 Madrid, Spain


The Diels-Alder reaction between complex 2,5-disubstituted furan derivatives and dimethyl acetylenedicarboxylate has been studied. Some synthetic applications of the cycloadducts are considered.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1803 - 1808
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DOI: 10.3987/COM-93-6364
Synthesis of 5-Aryl-3-hydroxy-4H-pyran-4-ones

Hisashi Takao,* Yoshinori Endo, and Tokunaru Horie

*Naruto Research Center, Otsuka Chemical Company, Ltd., S atoura,Naruto 772, Japan


The palladium-catalyzed coupling reaction of 3-benzyloxy-5-bromo-2-methyl-4H-pyran-4-one (2b) with phenylboronic acid afforded efficiently 3-benzyloxy-2-methyl-5-phenyl-4H-pyran-4-one (3b-1), and the benzyloxy group of the resultant product was cleaved by hydrolysis with conc. hydrochloric acid in acetic acid to give 5-phenyl-3-hydroxy-2-methyl-4H-pyran-4-one (4b-1) in high yield. This method was applicable as a general method for synthesizing 5-aryl-3-hydroxy-4H-pyran-4-ones (4) from the 5-bromo-4H-pyran-4-ones (1).

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1809 - 1821
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DOI: 10.3987/COM-93-6366
Synthesis and Structural Study of New Saturated Isoindol-1-one Derivatives

Ferenc Csende,* Zoltán Szabó, and Géza Stájer

*Alkaloida Chemical Co. Ltd., H-4440 Tiszavasvári, POB 1, Hungary


Condensation of 2-p-toluoylcyclohexanecarboxylic acid (1a,b) with primary amines gave the corresponding hexahydroisoindol-1-ones (2a-g) in good yield. The octahydro derivatives (4a-g) were prepared from cis- and trans-hexahydro-1(2H)-phthalazinone (3a,b) by reduction with zinc-hydrochloric acid via ring contraction. Stereoselective synthesis of cis-N-phenyloctahydroisoindol-1-one (4h) was performed starting from 2b by reduction with magnesium-methanol at room temperature. Configurational assignments of cis and trans isomers were based on 1H- and 13C-nmr spectroscopic studies.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1823 - 1836
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DOI: 10.3987/COM-93-6372
Synthesis of (+)-Preussin

Makoto Shimazaki, Fumiaki Okazaki, Fumihiro Nakajima, Tetsuya Ishikawa, and Akihiro Ohta*

*Tokyo College of Pharmacy , 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan


A total synthesis of (+)-preussin (1), a novel antifungal agent, was achieved via asymmetric 1,3-dipolar cycloaddition of decyl methyl nitrone (2) with (-)-1-phenyl-3-buten-2-ol (3) as a key reaction.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1837 - 1843
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DOI: 10.3987/COM-93-6382
Preparation of [Cys2]-RA-VII; The First Sulfur Containing Analogue of RAS Possessing Antitumor Activity

Hideji Itokawa,* Kazuyuki Kondo, Yukio Hitotsuyanagi, and Koichi Takeya

*Department of Pharmacognosy, Tokyo College of Pharmacy , 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan


RA-III (2), a potent antitumor cyclic hexapeptide, has been converted to [Cys2]-RA-VII (5) via thiolacetate (3). Derivatives (3) and (5) showed antitumor activities against P388 leukemia cells in vitro and in vivo.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1845 - 1849
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DOI: 10.3987/COM-93-6385
Synthesis of a Novel Water-soluble Cyclophane Having Eight Carboxymethylthiomethyl Groups on the Aromatic Rings

Muneharu Miyake,* Makoto Kirisawa, and Kenji Koga

*College of Pharmacy, Nihon University, 7-7-1 Narashinodai, Funabashi-shi, Chiba 274-8555, Japan


A novel cyclophane (9) having eight carboxyl groups that are attached one the aromatic rings via a spacer (-CH2SCH2-) was designed and synthesized as a host for cationic, anionic, and neutral aromatic guests in alkaline water. Macrocyclization of 7 with 6 was carried out under high dilution condition to give the objective 8 in 17% yield.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1851 - 1857
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DOI: 10.3987/COM-93-6386
Inclusion Complex Formation between a Novel Anionic Cyclophane and Cationic Aromatic Guests in Aqueous Solution

Muneharu Miyake, Makoto Kirisawa, and Kenji Koga*

*Faculty of Pharmaceutical Sciences, University of Tokyo,Hongo, Bunkyo-ku, Tokyo 113, Japan


1H-Nmr spectral studies have shown that a negatively charged cyclophane (2) having eight carboxylate groups that are bonded directly on the aromatic rings forms 1:1 inclusion complexes selectively with positively charged aromatic compounds as guests in alkaline water.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1859 - 1866
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DOI: 10.3987/COM-93-6391
Nucleophilic Substitution Reaction of 1-Hydroxytryptophan and 1-Hydroxytryptamine Derivatives (Regioselective Syntheses of 5-Substituted Derivatives of Tryptophane and Tryptamine)

Masanori Somei* and Yoshikazu Fukui

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


Regioselective nucleophilic substitution at the 5-position of indole nucleus was observed in the reaction of 1-hydroxytryptophan and 1-hydroxytryptamine derivatives with acids, suggesting the mechanism of serotonin formation in the central nervous system.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1867 - 1882
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DOI: 10.3987/COM-93-6394
A Facile Synthesis of Highly Functionalized Unsymmetrical Heterobiaryls Utilizing the Intramolecular Ullmann Coupling Reaction Directed by Salicyl Alcohol as a Template

Masami Takahashi, Tooru Kuroda, Tsuyoshi Ogiku, Hiroshi Ohmizu, Kazuhiko Kondo, and Tameo Iwasaki*

*Department of Synthetic Chemistry, Research Laboratory of Applied Biochemistry, Tanabe Seiyaku Co.Ltd., 3-16-89 Kashima, Yodogawa, Osaka 532, Japan


The cyclic heterobiaryls (3) containing a thenoyl or furoyl group were synthesized in good yields by regioselective acylations of salicyl alcohol (1), followed by the intramolecular Ullmann coupling reaction of the diesters (2). The cleavage of the two ester bonds of 3 by hydrogenolysis or nucleophilic substitution reactions proceeded regioselectively to afford the highly functionalized unsymmetrical heterobiaryls (4-6) in good yields.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1883 - 1895
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DOI: 10.3987/COM-93-6395
Protection and Deprotection of Fused 2-Amino-4(3H)-pyrimidinones: Conversion of Pterins and 5-Deazapterins to 2,4-Diamino Derivatives

Edward C. Taylor,* S. R. Otiv, and (in part) Inci Durucasu

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


5-Deazapterins and pterins are readily converted to their 4-deoxy-4-amino derivatives (a lactam-to-amidine conversion) by reaction with 4-chlorophenyl phosphorodichloridate and 1,2,4-triazole to give intermediate 4-[1’-(1,2,4-triazolyl)] derivatives, followed by reaction with aqueous ammonia. Some anomalous results obtained by application of the Mitsunobu reaction (normally a lactam-to-lactim ether conversion) to 5-deazapterins are detailed.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1897 - 1908
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DOI: 10.3987/COM-93-6400
Syntheses of a Regioisomer of N-{4-[2-(2-Amino-4(3H)-oxo-7H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoyl}-L-glutamic Acid (LY231514), an Active Thymidylate Synthase Inhibitor and Antitumor Agent

Edward C. Taylor,* Wendy B. Young, Rajendra Chaudhari, and Hemantkumar H. Patel

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


Two independent routes to N-{4-[2-[2-amino-4(3H)-oxo-7H-pyrrolo[2,3-d]pyrimidin-6-yl)ethyl]benzoyl}-L-glutamic acid, a regioisomer of the potent TS inhibitor and antitumor agent LY231514, are described. Preliminary in vitro cell culture evaluation has shown that attachment of the ethanobenzoylglutamate moiety of LY231514 to postition 6 of the pyrrolopyrimidine ring system rather than to position 5 results in complete loss of biological activity.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1909 - 1924
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DOI: 10.3987/COM-93-6404
Synthesis of 2(1H)-Quinolinonequinones and 2-Alkoxyquinolinequinones Using Oxidative Demethylation with Cerium (IV) Ammonium Nitrate

Yoshiyasu Kitahara, Shinsuke Nakahara, Masaro Shimizu, Takanobu Yonezawa, and Akinori Kubo*

*Meiji College of Pharmacy, 1-35-23 Nozawa, Setagaya-ku, Tokyo 154, Japan


2,5,8(1H)-Quinolinetriones (12), 2,5,6(1H)-quinolinetriones (13), 2-alkoxy-5,8-quinolinediones (14), 2,8-dimethoxy-5,6-quinolinedione (15), and 2,6-dimethoxy-7,8-quinolinediones (16) were synthesized by oxidative demethylation of the corresponding 2(1H)-quinolinones (7) and 2-alkoxyquinolinones (11) with cerium (IV) ammonium nitrate.

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Paper | Regular issue | Vol 36, No. 8, 1993, pp. 1925 - 1932
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DOI: 10.3987/COM-93-6411
Syntheses of 1-Benzyloxyaminoalkylphosphonates

Richard Neidlein* and Holger Keller

*Pharmazeutisch Chemishes Institut, Im Neuenheimer Feld 364, 6900 Heidelberg, Germany


A synthesis of 1-benzyloxyaminoalkylphosphonates was achieved via ionic hydrogenation of diethyl 1-benzyloxyiminoalkylphosphonates by triethylsilane-trifluoroacetic acid. Diethyl 1-benzyloxyaminomethylphosphonate, which could not prepared by reduction, was synthesized by a simple one pot reaction.

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26 data found. 1 - 26 listed