HETEROCYCLES
An International Journal for Reviews and Communications in Heterocyclic ChemistryWeb Edition ISSN: 1881-0942
Published online by The Japan Institute of Heterocyclic Chemistry
Special Issue
Herbert C. Brown's Special Issues, Vol. 18, No. 1, 1982
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■ Limonylborane: The First Borabicyclane as a Chiral Hydroborating Agent
Prabhakar K. Jadhav* and Surendra U. Kulkarni
*Wetherill Laboratory, Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, U.S.A.
Abstract
The first bicyclic chiral hydroborating agent, limonylborane (LimBH) has been prepared via the cyclic hydroboration of (+)-limonene with monochloroborane, followed by hydridation with LiAlH4. Hydroboration of representative alkenes with LimBH proceeds with a high degree of asymmetric induction, preferentially from one enantiotopic face of the alkene, to provide products of the same absolute configuration.
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■ Pyrazolopyridazinones by 1,3-Dipolar Cycloaddition of Diazomethane to Pyridazin-3(2H)-ones
Francisco Fariña,* M. Victoria Martín, Félix Sánchez, and Amelia Tito
*Departamento de Química Orgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain
Abstract
N-methylpyridazin-3(2H)-ones 1-3 react slowly with diazomethane to give, as main products, the N,N’-dimethylpyrazolo[3,4-d]pyridazin-4(5H)-ones 10a and 10b in a 1 : 2 ratio. The reaction of diazomethane with the N-methyl-4-bromopyridazin-3(2H)-one (4) leads to N1,N6-dimethylpyrazolo[3,4-d]pyridazin-7(6H)-one (9a). In the first case, the regioselectivity of the primary 1,3-dipolar cycloaddition is the reverse of that observed in enone systems.
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■ Peroxidation of Azirines. A Search for Oxazabicyclobutanes
Alfred Hassner,* Benjamin A. Belinka, Jr., and Alvin S. Steinfeld
*Department of Chemistry, State University of New York at Binghamton, Binghamton, New York 13901, U.S.A.
Abstract
Nucleophilic as well as electrophilic epoxidation of azirines leads to N-acylimines or their derivatives, possibly by way of an oxazabicyclobutane.
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■ Conjugate (1,4) Addition of Heterocyclic Acyl Anion Equivalents to Cyclic α-Enones in the Presence of Hexamethylphosphoric Triamide: A General Reaction
Charles Allan Brown,* O. Chapa, and A. Yamaichi
*IBM Research Laboratory, K34 / 281, 5600 Cottle Road, San Jose, CA 95193, U.S.A.
Abstract
Heterocyclic dithiaorganolithium reagents react with cyclic α-enones in THF to yield only products of carbonyl (1,2) addition; in the presence of 2.0 equivalents of hexamethylphosphoric triamide, the addition proceeds to give nearly exclusively the products of conjugate (1,4) addition in good yield.
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■ A Novel Method for the Synthesis of Substituted Tetrathia, Diselenadithia, and Tetraselenafulvalenes
Joseph E. Rice, Piotr Wojciechowski, and Yoshiyuki Okamoto*
*Department of Chemistry, Polytechnic Institute of New York, 333 Jay Street, Brooklyn New York 11201, U.S.A.
Abstract
A one-step synthesis of tetrathia-, diselenadithia-, and tetraselenafulvalenes at high pressure from CS2, CSSe, CSe2, and acetylenes substituted with electron withdrawing groups such as COOH, COOCH3 and CONH2 has been reported. Reactions with CS2 were found to proceed best at pressures >4000 atm and at 75-100°C. Reaction times in excess of 10 hours were generally employed. CSSe was reacted similarly with these acetylene compounds. Lower temperatures (~60°C) were needed for reactions involving CSe2, as this is known to be more reactive than CS2. Products were obtained in yields >85% and in a high degree of purity. Reactions with propiolic acid gave lower yields, as CO2 was evolved from the reaction mixture.
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■ Improved Synthesis of 3’-Nor-1-oxacephems
Tsutomu Aoki,* Kyoji Minami, Tadatoshi Kubota, Yoshio Hamashima, and Wataru Nagata
*Shionogi Research Laboratories, Shionogi & Co. Ltd., Fukushima-ku, Osaka 553-0002, Japan
Abstract
Several improved synthetic routes to 7α-unsubstituted and 7α-methoxylated 3’-nor-1-oxacephems, 3 and 4, from 7α-benzoylamino-3-methylene-1-oxacepham 2 were established.
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■ Synthesis of Spiro-nitrogen Multicyclic Systems Containing Macrocycles by Photocyclization of N-(ω-Inden-3-ylalkyl)phthalimides
Minoru Machida,* Kazuaki Oda, and Yuichi Kanaoka
*Faculty of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, Kita 12 Nishi 6, Kita-ku, Sapporo, Hokkaido 060-0812, Japan
Abstract
Photolysis of the N-(ω-inden-3-ylalkyl)phthalimides 1 in methanol gave spiro-nitrogen multicyclic systems 3 containing macrocycles up to 13-membered in good yields.
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■ A Simple Synthesis of Yohimban, Alloyohimban, and Alloyohimbone by Reductive Photocyclization of Enamides
Takeaki Naito, Yukiko Tada, Yoshino Nishiguchi, and Ichiya Ninomiya*
*Kobe Women’s College of Pharmacy, Motoyamakita, Higashinada, Kobe, Hyogo 658, Japan
Abstract
A simple synthesis of yohimban (6a) and alloyohimban (6b), and alloyohimbone (10) was achieved by reductive photocyclization of the enamides (1a) and (1b) in the presence of sodium borohydride respectively.
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■ Synthesis of 2,4-Dimethyl-1,2,3,4,4a,5,6,10b-octahydrobenzo(f)quinolines and Their Derivatives by Reductive Photocyclization of Enamides
Toshiko Kiguchi, Chiyomi Hashimoto, Takeaki Naito, and Ichiya Ninomiya*
*Kobe Women’s College of Pharmacy, Motoyamakita, Higashinada, Kobe, Hyogo 658, Japan
Abstract
Reductive photocyclization of the enamides (1 and 7) afforded the hydrogenated lactams (4a, 5a, and 6a) and (8, 9, and 10) respectively, which were readily converted into the corresponding octahydrobenzo(f)quinolines (4b, 5b, and 6b) and hexahydrobenzo(f)quinoline (12) as the despyrrole analogues of ergot alkaloids.
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■ Autoxidation of Arylcycloalkenes: A Method for the Preparation of Epoxides
Shanti C. Sethi,* Arun D. Natu, and Murzban S. Wadia
*National Chemical Laboratory, Poona-411 008, India
Abstract
A method for the preparation of arylcycloalkene epoxides has been developed via the autoxidation of the corresponding arylcycloalkenes.
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■ Syntheses of Erythrina and Related Alkaloids(6). Total Synthesis of Erysotrine and Erythraline
Takehiro Sano,* Jun Toda, and Yoshisuke Tsuda
*Showa College of Pharmaceutical Sciences, Setagaya-Ku, Tokyo 154, Japan
Abstract
An efficiently stereocontrolled synthesis of the erythrina alkaloids, erysotrine and erythraline was described.
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■ Simple Synthesis of Monoisopinocampheylborane via the Bis Adduct with Triethylenediamine
Prabhakar K. Jadhav* and Manoj C. Desai
*Wetherill Laboratory, Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, U.S.A.
Abstract
The reaction between diisopinocampheylborane (Ipc2BH) and triethylenediamine (TED) at 35°C occurs rapidly with displacement of α-pinene to form a solid 1:2 adduct (mp 160-161°C) of the diamine and monoisopinocampheylborane (2IpcBH2·TED). Generation of free monoisopinocampheylborane is readily achieved by precipitation of TED·2BF3 by simple treatment of the adduct with boron trifluoride etherate.
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■ The Synthesis of Dehydroperloline
Rolf Prager,* Thach Duong, and Stuart Clarke
*Department of Organic Chemistry, University of Adelaide, G.P.O. Box 498, Adelaide, S.A. 5001, Australia
Abstract
Fluorenone and 3-aza-4-oxo-3,4-dihydrofluorenone react with 3,4-dimethoxyphenyllithium to form the corresponding fluorenols, which react with hydrazoic acid to form the phenanthridine. The N-oxides photolyse smoothly to yield dehydroperloline and its analogue as the sole product.
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■ Stereospecific Alkylation of Sulfur-stabilized Carbanion in Dithiabicyclo[3.1.0]hexane Systems
Renji Okazaki,* Masaharu O-oka ,Takahiko Akiyama, and Naoki Inamoto
*Department of Chemistry, Faculty of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033
Abstract
The sulfur-stabilized carbanion formed from dithiabicyclo[3.1.0]hexane systems (1) and (2) reacted with various electrophiles to give endo products highly stereospecifically.
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■ Generation and Capture of Triphenylborirene in the Di-π-Methane-like Photorearrangement of Diphenyl(phenylethynyl)borane-pyridine
John J. Eisch,* Fengjia Shen, and Kohei Tamao
*Department of Chemistry, State University of New York at Binghamton, Binghamton, New York 13901, U.S.A.
Abstract
The photorearrangement of diphenyl(phenylethynyl)borane-pyridine in benzene solution with irradiation at 254 nm leads to the formation of triphenylborirene(triphenylboracyclopropene), as evidenced by: a) the formation of α,α’-dideuterio-cis-stilbene upon treatment of the photolysate solution with DOAc; and b) the isolation of pentaphenylborole-pyridine from a photorearrangement conducted in the presence of diphenylacetylene. The triphenylborirene system was shown to be extremely sensitive to oxygen and to protic agents.
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■ A Novel Synthesis of the Sulfur Analog of Δ6-PGI1
Hiroko Yokomori, Yasuhiro Torisawa, Masakatsu Shibasaki, and Shiro Ikegami*
*Faculty of Pharmaceutical Sciences, Teikyo University, 1091-1 Suarashi, Sagamiko-machi, Tsukui-gun, Kanagawa 199-0195, Japan
Abstract
The sulfur analog of Δ6-PGI1 (1), a chemically stable and biologically interesting analog of prostacyclin, was synthesized from PGE2, including the novel acid-catalyzed isomerization of the exo-thioenol ether (11) to the endo-isomer (12) as a key step.
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■ A Formal Total Synthesis of (±)-Vincamine
Kunihiko Irie and Yoshio Ban*
*Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-ku, Sapporo, Hokkaido 060-0812, Japan
Abstract
Anodic oxidation of 1-carbomethoxy-3-ethyl-3-(β-carboxyethyl)·piperidine (4) in methanol followed by treatment of formic acid provided the lactone 7, from which was synthesized (±)-homoeburnamonine (15), achieving a formal total synthesis of (±)-vincamine (3).
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■ Synthesis of Both Enantiomers of 8-Aza-11-deoxy-10-thiaprostaglandin E1
Noboru Kubodera,* Hiroyuki Nagano, Michiro Takagi, and Isao Matsunaga
*New Drug Research Laboratories, Chugai Pharmaceutical Company, Ltd., Takada 3-41-8, Toshima-ku, Tokyo 171, Japan
Abstract
Synthesis of both enantiomers of 8-aza-11-deoxy-10-thiaprostaglandin E1 has been achieved starting from D- and L-cysteine, respectively.
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■ Highly Regioselective Reduction of Unsymmetrical Cyclic Anhydrides to Lactones with Hindered Trialkylborohydrides
S. Krishnamurthy* and William B. Vreeland
*Research Laboratories, Eastman Kodak Company, Rochester, New York 14650, U.S.A.
Abstract
Lithium trialkylborohydrides reduce cyclic anhydrides to the corresponding lactones in good to excellent isolated yields. With unsymmetrical anhydrides, increasing the steric requirements of the trialkylborohydride dramatically enhances the regioselectivity of the reduction of the less hindered carbonyl group of the anhydride.
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■ Synthesis of cis and trans Decalins by Boron Annulation
Eric J. Levine and Thomas A. Bryson*
*Department of Chemistry, University of South Carolina , Columbia, South Carolina 29208, U.S.A.
Abstract
Hydroboration and cyanidation of 1,4-diene 1 afforded bicyclic compounds 2 (trans) and 3 (cis). Boron annulation of diene 7 (R=CH3) yielded cis and trans decalones. Simple and competitive hydroboration of 1,4-dienes 1 and 7(R=CH3 and Sφ) were analyzed for regio- and stereoselectivity.
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■ Boron Annulation: Synthesis of trans -Decalin Natural Product Synthons
Curtis J. Reichel* and Thomas A. Bryson
*Department of Chemistry, University of South Carolina , Columbia, South Carolina 29208, U.S.A.
Abstract
Boron annulation of olefins 3, 4 and 14 has afforded decalin syothons 1 and 2 and perhydrophenanthrone 15, respectively. The A, B ring juncture of 15 and the ring systems of 1 and 2 were found to be trans.
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■ Transformation of Allylic Epoxides to Tetrahydrofurfuryl Alcohols via Hydroboration
Marek Zaidlewicz* and Ryszard Sarnowski
*Institute of Chemistry, Nicolas Copernicus University, 87-100 Torun, Poland
Abstract
The allylic epoxides 1-4 were transformed to the tetrahydrofurfuryl alcohols 17-20, respectively. The formation of 6 and 10 in the hydroboration-oxidation of 4 is interpreted. The monohydroboration-oxidation of 13 and 14 gave 15 and 16, respectively.
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■ Unusual Thermal Isomerization of β-Alkylboracyclanes; Evidence for Low Steric Requirements of Boracyclanes in Thermal Isomerization
Uday S. Racherla* and Ganesh G. Pai
*Wetherill Laboratory, Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, U.S.A.
Abstract
The thermal isomerizations of β-3-hexylborolane (5), β-3-hexylborinane (6) and β-3-hexylborepane (7) were compared under identical conditions: 150°C in diglyme. The rates of isomerization decreased with decreasing steric requirements of the boracyclane. For example, the rate of thermal isomerization of β-3-hexylborepane (7) is 2 times greater than that of β-3-hexylborinane (6) and 5 times greater than that of β-3-hexylborolane (5). Moreover, the least sterically crowded β-3-hexylborolane (5) yielded an equilibrium mixture which contained more boron distributed on the terminal primary carbon atom compared to the equilibrium mixtures derived from β-3-hexylborinane (6) and β-3-hexylborepane (7).
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■ Dimerisation of Cinnamalaniline with Potassium Cyanide: A Novel Synthesis of 4,5-trans-Diphenyl-1-phenyl-2-phenylimino-2,3,4,5-tetrahydro-1H -azepine
Gurbakhsh Singh and Arun K Mandal*
*Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi - 221005, India
Abstract
Reaction of cinnamalaniline 1b with potassium cyanide in dimethylsulfoxide or dimethylformamide gave rise to 4,5-trans-diphenyl-1-phenyl-2-phenylimino-2,3,4,5-tetrahydro-1H-azepine 5 in 15% yield. The structure was established from spectroscopic data and degradation study.
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■ Studies on the Synthesis of Chemotherapeutics. Part XIII. Synthesis and Biological Studies on Phosphonopeptides Having Alkyl-, Phenyl-, and Heterocyclic Substituents
Tetsuji Kametani,* Yukio Suzuki, Kazuo Kigasawa, Mineharu Hiiragi, Kikuo Wakisaka, Hideo Sugi, Keizo Tanigawa, Kazunaga Fukawa, Osamu Irino, Osamu Saita, and Shigeru Yamabe
*Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
Abstract
New antibacterial phosphonopeptides (3) were synthesized in order to improve the stability against hydrolysis by peptidase and the antibacterial spectra. Synthesis of them was accomplished by condensation of the N-carbobenzoxyamino acid with diethyl aminoalkylphosphonate followed by deprotection and hydrolysis. The antibacterial activity was evaluated in a defined medium and the stability against hydrolysis by rat liver homogenates was examined. Chemical modification of the N-terminal amino acid moiety of the phosphonopeptide containing sulfur or oxygen atom at β- or γ-position of the N-terminal α-amino acid residue lost rapidly their in vivo activity in spite of the high in vitro activity. The para substituted phenylalanyl-1-aminoethyl-phosphonic acids showed higher stability and slightly lower activity compared with those of the corresponding ortho- and meta-substituted isomers. Some of these para-substituted compounds (e.g. 9β, 10β, and 19β) exhibited the same level of the biological activity as that of Alafosfalin (1) in potency of the activity, broadness of the spectrum, and the serum level in mice after peroral administration. Phosphonopeptides consisted of unnatural amino acids and aminomethylphosphonic acid showed generally the extended spectra and activities, but these compounds were very fragile to hydrolysis by peptidase. None of phosphonopeptides containing 2-aminoethylphosphonic acid had the activity.
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■ Oxidation of 9-Borabicyclo[3.3.1]nonane and Its Derivatives with Pyridinium Chlorochromate
Surendra U. Kulkarni,* C. Gundu Rao, and Vemanna D. Patil
*Wetherill Laboratory, Purdue University, West Lafayette, Indiana 47907, U.S.A.
Abstract
The oxidation of 9-borabicyclo[3.3.1]nonane (1) with chromic acid or pyridinium chlorochromate (PCC) affords a mixture of products, predominantly cyclooctanone (> 65%). However, cis-1,5-cyclooctanediol (2), readily obtained from 1 by oxidation with alkaline hydrogen peroxide, is oxidized by these reagents to provide 9-oxabicyclo[3.3.1]nonan-1-ol (4). Under more drastic conditions, 2 and 4 can be transformed by PCC into 1,5-cyclooctanedione (5). Consequently, it is now possible to proceed easily from 1,5-cyclooctadiene via hydroboration-oxidation to cis-1,5-cyclooctanediol (2), to 9-oxabicyclo[3.3.1]nonan-1-ol (4) and 1,5-cyclooctanedione (5).
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■ Central Nervous System Active Compounds XI. 1-(3-Phthalidyl)phthalazin-4-ones
Rolf Prager,* A. David Ward, Philip Marshall, and Brett Mooney
*Department of Organic Chemistry, University of Adelaide, G.P.O. Box 498, Adelaide, S.A. 5001, Australia
Abstract
Phthalidylphthalazinones can be readily prepared by the reaction of hydrazines with the corresponding biphthalide. The reaction with unsymmetrical biphthalides appears to be controlled mainly by electronic factors. Phthalidylphthalazinone undergoes the Mannich reaction leading to a 3-substituted product. 1-Chlorophthalazine reacts with butyllithium by addition at C-4; the resulting anion is alkylated at C-3 with methyl 2-formylbenzoate. The compounds cause loss of muscular control in mice, but their insolubility hinders further pharmacological investigation.
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■ Cycloadducts Derived from Sulfenes or Ketenes and Tropone or Analogs of Tropone
William E. Truce* and Barry D. Dean
*Wetherill Laboratory, Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, U.S.A.
Abstract
Tropone and analogs of tropone (i.e., iminotropones or 8-azaheptafulvenes, and thiotropone) react with sulfenes as well as ketenes forming cycloadducts, wherein a new five-membered ring has been generated. The cycloadducts in turn undergo interesting conversions via a cycloheptatrienenorcaradiene-ring opening sequence.
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■ Oraganometallic Compounds for Stereoregulated Synthesis of Acyclic Systems. Their Application to the Synthesis of the Prelog-Djerassi Lactonic Acid
Yoshinori Yamamoto* and Kazuhiro Maruyama
*Department of Chemistry, Faculty of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan
Abstract
Acyclic stereoselection via organometallic compounds (M = Li, Mg, Zn, Cd, Cu, B, Al, Si, Sn, Ti, Zr, Cr, and Pd) is surveyed. Application of the organometallics to the synthesis of the Prelog-Djerassi lactonic acid is described along with other approaches.
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■ Addition Compounds of Boron Trifluoride, Boranes and Alane with N,N,N’,N’-Tetramethylethylenediamine and Triethylenediamine
Bakthan Singaram* and Ganesh G. Pai
*Wetherill Laboratory, Purdue University, West Lafayette, Indiana 47907, U.S.A.
Abstract
This review summarizes the studies conducted in the Richard B. Wetherill Laboratory on the synthesis of addition compounds of boron trifluoride, boranes and alane with N,N,N’,N’-tetramethylethylenediamine and the heterocycle, triethylenediamine. The applications of such addition compounds are also briefly discussed.