Special Issue

Isao Kuwajima's Special Issues, Vol. 90, No. 2, 2015

55 data found. 31 - 55 listedFirst Previous
Paper | Special issue | Vol 90, No. 2, 2015, pp. 1142 - 1157
Published online: 28th August, 2014
DOI: 10.3987/COM-14-S(K)86
Stereoselective Construction of 1β-Azide- and 1β-Cyano-2-deoxyribose Derivatives

Hiromichi Fujioka,* Takahiro Moriya, Kazuhisa Okamoto, Yutaka Minamitsuji, Yoshifumi Ueyama, Nao Matsumoto, and Kenichi Murai

*Graduate School of Pharmaceutical Science, Osaka University, 1-6 Yamadaoka, Suita, Osaka 560-0871, Japan


A new method has been developed for the β-selective introduction of azido and cyano groups at the anomeric position of 2-deoxyribose derivatives. This method proceeds via the formation of a collidinium salt intermediate and allows for the stereoselective construction of 1β-azido- and 1β-cyano-2-deoxy-D-ribose derivatives. 2-Deoxy-D-ribose compounds bearing an acetoxy or tert-butoxycarbonyloxy group at their anomeric position performed well as starting materials for the formation of the corresponding 1β-azide and 1β-cyanide derivatives, respectively. 1H NMR studies of the salt intermediates revealed that the nucleophilic substitution reaction of the salt intermediates proceeded in a SN2-fashion.

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Paper | Special issue | Vol 90, No. 2, 2015, pp. 1158 - 1167
Published online: 19th August, 2014
DOI: 10.3987/COM-14-S(K)91
4,8-Dihydropyrrol[3,4-f]isoindole as a Useful Building Block for Near-Infrared Dyes

Hidemitsu Uno,* Mitsunori Nakamura, Kazuki Jodai, Shigeki Mori, and Tetsuo Okujima

*Department of Chemistry and Biology, Graduate School or Science and Engineering, Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577, Japan


4,8-Dihydropyrrol[3,4-f]isoindole was prepared from 4,7-dihydroisoindole based on the modified Barton-Zard reaction. Addition of phenylsulfenyl chloride followed by oxidation and dehydrochlorination gave phenylsulfonyldihydroisoindole, which underwent the smooth reaction with an isocyanoacetate under basic conditions to give 4,8-dihydropyrrol[3,4-f]isoindole-1,5- and 1,7-dicarboxylates in good yields. The pyrrolisoindole was successfully converted to the benzene-fused bisBODIPY, absorption maximum of which was 758 nm.

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Paper | Special issue | Vol 90, No. 2, 2015, pp. 1168 - 1178
Published online: 11th September, 2014
DOI: 10.3987/COM-14-S(K)92
Synthesis of Pyrrolidinofullerenes via Single Electron Transfer Reaction of Aryldienamines with C60

Naohiko Ikuma,* Hiroyuki Yamamoto, Ken Kokubo, and Takumi Oshima

*Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan


Variously aryl-substituted pyrrolidinofullerenes were synthesized via a single electron transfer (SET) reaction of diaryldienamines with C60 and the following consecutive 1,6-hydrogen shift and the [3 + 2] cycloaddition of the generated radical ion pair. The LUMO levels of pyrrolidinofullerenes were ca. 0.1 eV higher than C60, consequently suppressing the bisadduct formation. The phenyl –substituted pyrrolidinofullerene 2a representatively exhibited the protic acid-catalyzed intramolecular Friedel–Crafts cyclization and the DDQ induced oxidative reversion into C60.

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Paper | Special issue | Vol 90, No. 2, 2015, pp. 1179 - 1195
Published online: 20th August, 2014
DOI: 10.3987/COM-14-S(K)93
Total Synthesis of Maremycins A and D1 Using Chiral and Cyclic Nitrone with (E)-3-Ethylidene-1-methylindolin-2-one

Tohru Ueda, Mitsuhide Inada, Nobuyoshi Morita, and Osamu Tamura*

*Laboratory of Organic Chemistry, Pharmaceutical Sciences, Showa Pharmaceutical University, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan


Total syntheses of maremycin A (4) and maremycin D1 (8) were described, featuring 1,3-dipolar cycloaddition of a chiral cyclic nitrone 15 with (E)-3-ethylidene-1-methylindolin-2-one (13). The cycloaddition was reversible, especially at high temperature in the presence of a Lewis acid or in a solvent possessing a high acceptor number. One of the cycloadducts was efficiently led to maremycin A (4) and maremycin D1 (8). High optical purity of 4 was confirmed by chiral HPLC comparison with ent-4 prepared from ent-15 and 13.

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Paper | Special issue | Vol 90, No. 2, 2015, pp. 1196 - 1204
Published online: 23rd October, 2014
DOI: 10.3987/COM-14-S(K)94
Lithium tert-Butoxide-Mediated Carboxylation Reactions of Unprotected Indoles and Pyrroles with Carbon Dioxide

Woo-Jin Yoo, Thanh V. Q. Nguyen, Montse Guiteras Capdevila, and Shū Kobayashi*

*Department of Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan


Unprotected indoles and pyrroles were found to undergo base-mediated carboxylation reactions under ambient pressure of carbon dioxide. It was found that this transition metal-free carboxylation reaction proceeded smoothly with the use of a large excess of LiOtBu.

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Paper | Special issue | Vol 90, No. 2, 2015, pp. 1205 - 1213
Published online: 5th September, 2014
DOI: 10.3987/COM-14-S(K)100
Thiazole/Thiazolone-Fused Cycloheptatrienyl Phosphonates: Reactions of 2H-Cyclohepta[d]thiazole-2-thione and -2-one with Phosphites

Ohki Sato* and Ikumi Suzuki

*Department of Chemistry, Graduate School of Science and Engineering, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama 338-8570 , Japan


2H-Cyclohepta[d]thiazole-2-thione reacted with either trimethyl or dimethyl phosphite to furnish dimethyl 2-methylthio-4H-cyclohepta[d]thiazole-4-phosphonate and the regioisomers, 6- and 8-phosphonates. In the reaction with triphenyl phosphite, the successive S-methylation by methyl iodide and hydrolysis afforded an isomeric mixture of diphenyl 4-, 6- and 8-phosponates. Treatment of the oxygen analogue, 2H-cyclohepta[d]thiazol-2-one and triphenyl/diphenyl phosphite with/without hydrolysis gave diphenyl 3,4-dihydro-2H-cyclohepta[d]thiazol-2-one-4-phosphonate and the isomeric 6- and 8-phosphonates.

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Paper | Special issue | Vol 90, No. 2, 2015, pp. 1214 - 1227
Published online: 27th August, 2014
DOI: 10.3987/COM-14-S(K)101
Synthesis, Properties and Crystal Structures of 2,7,12,17-Tetraarylporphycenes

Daiki Kuzuhara,* Haruka Nakaoka, Takuya Okabe, Naoki Aratani, and Hiroko Yamada*

*Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan


We have synthesized 2,7,12,17-tetraarylporphycenes, which have phenyl (7a), p-trifluoromethylphenyl (7b) or p-methoxyphenyl (7c) groups, by McMurry coupling. The crystal structures revealed that 7a formed a herringbone-type arrangement, while 7b formed a slip-stacked structure with π-π stacking. The reduction potentials of these porphycenes depend on the attached aryl groups: –1.02 V (vs. ferrocene/ferrocenium cation) for 7b (Ar = p-C6H4CF3), –1.17 V for 7a (Ar = Ph) and –1.23 V for 7c (Ar = p-C6H4OMe), which are close to that of PC61BM (Ered = –1.08 V). These porphycenes, thus, are expected to behave as n-type semiconducting materials in OTFT and OPV devices.

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Paper | Special issue | Vol 90, No. 2, 2015, pp. 1228 - 1239
Published online: 29th October, 2014
DOI: 10.3987/COM-14-S(K)104
Efficient Desulfinative Cross-Coupling of Heteroaromatic Sulfinates with Aryl Triflate in Environmentally Friendly Protic Solvents

Daniel Mangel, Cindy Buonomano, Stéphane Sévigny, Gianna Di Censo, Gowsic Thevendran, and Pat Forgione*

*Department of Chemistry and Biochemistry, Concordia University, 7141 Sherbrooke Street West, SP 201.00, Montreal, Quebec, H4B 1R6, Canada


Aryl-substituted heteroaromatics were synthesized via desulfinative cross-coupling reactions using aryl triflate and heteroaromatic sulfinate coupling partners. This method uses synthetically versatile aryl triflates to access aryl-substituted heteroaromatics in good yields employing aqueous and alcoholic media without the use of base, additives or co-catalysts.

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Paper | Special issue | Vol 90, No. 2, 2015, pp. 1240 - 1253
Published online: 18th September, 2014
DOI: 10.3987/COM-14-S(K)106
Toward the Pluramycins: Route Exploration from Dihydroxyanthrone Tricyclic Platform to an Aglycon, Saptomycinone B

Kei Kitamura, Yoshio Ando, Yoshihiko Maezawa, Takashi Matsumoto,* and Keisuke Suzuki*

*Depatrtment of Chemistry, Tokyo Institute of Technology, 2-12-1,Oh-Okayama, Meguro-ku, Tokyo 152-8552, Japan


In connection with the total synthesis of the pluramycin-class antibiotics, we recently found dihydroxyanthrone derivatives to be suitable platforms for the installation of bis-C-glycosides. As a basis for the total synthesis, we explored viable routes to construct the characteristic tetracyclic skeleton. By setting saptomycinone B (5) as a model target, anthrone 6 was combined with the side chain moiety to access key intermediate 9, from which two viable routes have been developed. One of the routes has been exploited in the realization of our recent total synthesis of saptomycin B (4).

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Paper | Special issue | Vol 90, No. 2, 2015, pp. 1254 - 1273
Published online: 12th September, 2014
DOI: 10.3987/COM-14-S(K)107
Synthesis of the C1-C7 and C8-C18 Segments of ent-Amphidinin A

Haruaki Ishiyama, Masahiro Hangyou, Ayumi Nakatsu, Yuta Mori, and Jun'ichi Kobayashi*

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


A stereoselective synthesis of the C1-C7 and C8-C18 segments of the enantiomer of amphidinin A, a cytotoxic polyketide from the culture cells of a symbiotic marine dinoflagellate Amphidinium sp. (strain Y-5), has been achieved, utilizing sulfone-aldehyde coupling, Sharpless asymmetric dihydroxylation, Katsuki-Sharpless asymmetric epoxidation, and Julia-Kocienski olefination.

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Paper | Special issue | Vol 90, No. 2, 2015, pp. 1274 - 1287
Published online: 22nd September, 2014
DOI: 10.3987/COM-14-S(K)108
Synthesis and Preliminary Biological Evaluation of 2-[3-(Tetrazolyl)propyl]-1α,25-dihydroxy-19-norvitamin D3

Masashi Takano, Erika Higuchi, Kazunari Higashi, Keisuke Hirano, Akiko Takeuchi, Daisuke Sawada, and Atsushi Kittaka*

*Faculty of Pharmaceutical Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan


Four new 19-norvitamin D3 analogs, 2α-[3-(tetrazol-1-yl)propyl]-, 2β-[3-(tetrazol-1-yl)propyl]-, 2α-[3-(tetrazol-2-yl)propyl]-, and 2β-[3-(tetrazol-2-yl)propyl]-1α,25-dihydroxy-19-norvitamin D3 were synthesized. Among them, 2α-[3-(tetrazol-1-yl)propyl]-1α,25-dihydroxy-19-norvitamin D3 showed weak binding affinity for vitamin D receptor (VDR) (2.6% of 1α,25-dihydroxyvitamin D3: ca. 15% of 1α,25-dihydroxy-19-norvitamin D3) and weak VDR transactivation activity in human osteosarcoma cells, which was determined by luciferase assays (EC50 7.3 nM, when 1α,25-dihydroxyvitamin D3 0.23 nM). Although the other three compounds could not act as VDR binders by evaluation of the competition assays, 2α-[3-(tetrazol-2-yl)propyl] analog showed weak transactivation activity (EC50 12.5 nM).

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Short Paper | Special issue | Vol 90, No. 2, 2015, pp. 1289 - 1298
Published online: 13th August, 2014
DOI: 10.3987/COM-14-S(K)37
New Approach to Cyclophanes Containing Ethyleneoxy Bridge by Glaser–Eglinton Coupling

Sambasivarao Kotha* and Gopalkrushna T. Waghule

*Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai - 400076, India


Three strategies have been explored to generate cyclophane derivatives. In this regard, we identified alkyne metathesis, Diels–Alder reaction, and Glaser–Eglinton coupling as key steps. To this end, cyclophane derivatives containing ethyleneoxy bridge were successfully synthesized in four steps involving Glaser–Eglinton coupling and catalytic hydrogenation sequence.

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Short Paper | Special issue | Vol 90, No. 2, 2015, pp. 1299 - 1308
Published online: 5th August, 2014
DOI: 10.3987/COM-14-S(K)62
Stereochemistry of Vinylogous Rubottom Oxidation of Proline-Fused Cyclohexadienol Silyl Ether

Kentaro Okano, Shun Okaya, Taichi Kurogi, Hideto Fujiwara, and Hidetoshi Tokuyama*

*Department of Organic Chemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Aramaki, Aoba-ku, Sendai 980-8578, Japan


The steric effect of vinylogous Rubottom oxidation of proline-fused cyclohexadienol silyl ether was investigated. The facial selectivity in the oxidation is governed by a synergistic effect of the proximal ester and a protective group on the nitrogen.

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Short Paper | Special issue | Vol 90, No. 2, 2015, pp. 1309 - 1316
Published online: 5th August, 2014
DOI: 10.3987/COM-14-S(K)67
Synthesis of Rhodotorulic Acid and Its 1,4-Dimethylated Derivative

Michiyasu Nakao, Shintaro Fukayama, Syuji Kitaike, and Shigeki Sano*

*Molecular Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokushima, 1-78 Sho-machi, Tokushima 770-8505, Japan


Facile syntheses of rhodotorulic acid, isolated from Rhodotorula pilimanae as a siderophore, and its 1,4-dimethylated derivative have been achieved by microwave-assisted cyclization of the corresponding dipeptide precursors.

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Short Paper | Special issue | Vol 90, No. 2, 2015, pp. 1317 - 1322
Published online: 4th August, 2014
DOI: 10.3987/COM-14-S(K)68
Isolation of Alkamides with Death Receptor-Enhancing Activities from Piper chaba

Hoque Tahmina, Kazufumi Toume, Midori A. Arai, Samir K. Sadhu, Firoj Ahmed, and Masami Ishibashi*

*Department of Natural Products Chemistry, Graduate School of Pharmaceutical Science, Chiba University, 1-8-1 Inohana, Chuo, Chiba, Japan


In the screening program for natural bioactive compounds that enhance the expression of death receptor 5 (DR5), activity-guided fractionation of the Piper chaba (Piperaceae) root MeOH extract led to the isolation of four alkamides (1-4). Compounds 1, 3, and 4 enhanced DR5 promoter activity while pellitorine (3) exhibited TRAIL-resistance-overcoming activity.

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Short Paper | Special issue | Vol 90, No. 2, 2015, pp. 1323 - 1331
Published online: 10th October, 2014
DOI: 10.3987/COM-14-S(K)80
Palladium Catalyzed Intramolecular Vinylselenation and Vinylthiolation of Allenes

Susumu Tsuda, Maiko Okuyama, Shin-ichi Fujiwara,* Takanori Iwasaki, Hitoshi Kuniyasu, and Nobuaki Kambe*

*Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan


Intramolecular vinylselenation of allenes 1a,b proceeds in the presence of Pd(0) catalyst producing pyridin-2-one derivatives 2a,b having a high degree of unsaturation as a sole product. This cyclization could also be applied to vinylthiolation and to the construction of seven-membered lactams.

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Short Paper | Special issue | Vol 90, No. 2, 2015, pp. 1332 - 1342
Published online: 19th August, 2014
DOI: 10.3987/COM-14-S(K)84
Palladium-Mediated Intramolecular Biaryl Coupling Reaction: Convenient Preparation of Furoquinolinone Derivatives

Hitoshi Abe,* Mayu Kamimura, Yoshinori Komatsu, and Yoshikazu Horino

*Department of Environmental Applied Chemistry, Faculty of Engineering, Toyama University, Gofuku 3190, Toyama 930-8555, Japan


Furo[2,3-c] or furo[3,2-c]quinolinone derivatives were prepared via the intramolecular biaryl coupling reaction of 2-furoylanilides or 3-furoylanilides using a palladium catalyst.

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Short Paper | Special issue | Vol 90, No. 2, 2015, pp. 1343 - 1350
Published online: 6th August, 2014
DOI: 10.3987/COM-14-S(K)85
Synthetic Studies toward Welwitindolinone Alkaloids. Tandem Aldol–Michael Reaction to Form the Carbocyclic Core of Welwitindolinones

Masato Shima and Masahiro Toyota*

*Team TOYOTA, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuencho, Sakai, Osaka 593-8531, Japan


A tandem aldol ̶Michael reaction effectively constructed a bridged ketone, which is the carbocyclic core of the welwitindolinone family.

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Short Paper | Special issue | Vol 90, No. 2, 2015, pp. 1351 - 1366
Published online: 26th September, 2014
DOI: 10.3987/COM-14-S(K)87
Marine Natural Occurring 2,5-Diketopiperazines: Isolation, Synthesis and Optical Properties

Rémi Laville, Thanh Binh Nguyen, Céline Moriou, Sylvain Petek, Cécile Debitus, and Ali Al-Mourabit*

*Department of Chemistry, Institut de Chimie des Substances Naturelles, CNRS, 1, Avenue de la Terrasse, 91190 Gif-sur-Yvette, France


Seven 2,5-diketopiperazines (DKPs) were isolated from the Fijian marine sponge Acanthella cavernosa. NMR and circular dichroism (CD) comparison with synthetic L-L DKPs allowed us to determine unambiguously the L-L absolute configuration of the natural DKPs. This work initiated the setting up of an optical properties database of natural DKPs, including specific rotation and CD.

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Short Paper | Special issue | Vol 90, No. 2, 2015, pp. 1367 - 1374
Published online: 3rd October, 2014
DOI: 10.3987/COM-14-S(K)88
Natural-Product-Based Insecticidal Agents 16. Semisynthesis of C7-Oxime Sulfonate Ester Derivatives of Obacunone as Insecticidal Agents against Mythimna separata Walker

Xiang Yu, Guodong Ding, Zhinan Gao, Jing Zha, and Hui Xu*

*Laboratory of Pharmaceutical Design & Synthesis, College of Life Sciences, Northwest A & F University, Xinong Road 22#, Yangling, Shaanxi, 712100, China


A series of novel C7-oxime sulfonate ester derivatives of obacunone (3a-f) were synthesized. Their insecticidal activity was also evaluated at the concentration of 1 mg/mL against the pre-third-instar larvae of oriental armyworm (Mythimna separata Walker), a typical lepidopteran pest. Especially C7-oxime p-ethylphenylsulfonate ester of obacunone (3d) exhibited more potent insecticidal activity than their precursor obacunone and toosendanin (a positive control).

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Short Paper | Special issue | Vol 90, No. 2, 2015, pp. 1375 - 1386
Published online: 27th August, 2014
DOI: 10.3987/COM-14-S(K)89
Synthesis of Unsymmetrical, gem-Disubstituted Bisamides

Gabriel Schäfer, Lukas Leu, and Jeffrey W. Bode*

*Laboratory of Organic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Wolfgang-Pauli-Strasse 10, CH-8093 Zuerich, Switzerland


The addition of Grignard reagents to isocyanates allowed for the first successful synthesis of ketone-derived unsymmetrical, gem-disubstituted bisamides. The key to success was the in situ generation of the isocyanates under mild reaction conditions via Lossen rearrangement from the corresponding hydroxamic acids.

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Short Paper | Special issue | Vol 90, No. 2, 2015, pp. 1387 - 1395
Published online: 20th August, 2014
DOI: 10.3987/COM-14-S(K)95
A Concise Approach to Tetracyclic Spiroamine Scaffold of Erythrinan Alkaloids via an Oxidative Dearomatization-Spirocyclization Sequence

Emi Saito, Akihiko Nakamura, and Masahisa Nakada*

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


This paper describes a novel synthetic approach to 11,12-dimethoxy-8,9-dihydro-1H-indolo[7a,1-a]isoquinoline-2,6-dione, which is a key synthetic intermediate to some erythrinan alkaloids. This concise approach features an oxidative dearomatization-spirocyclization sequence mediated by phenyliodine (III) bis(trifluoroacetate) (PIFA) that efficiently forms the tetracyclic spiroamine scaffold. An unusual solvent effect in the oxidative dearomatization-spirocyclization sequence is also described.

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Short Paper | Special issue | Vol 90, No. 2, 2015, pp. 1396 - 1404
Published online: 8th September, 2014
DOI: 10.3987/COM-14-S(K)98
Synthesis of Intermediary P3 Phosphazenium Framework and Its Derivatization to Chiral Cationic Macrocycles Including Two P3 Phosphazenium Units with Hydrogen Bond Donor Sites

Masahiro Terada,* Kengo Goto, Takashi Ikehara, and Azusa Kondoh

*Department of Chemistry, Graduate School of Science, Tohoku University, Aramaki, Aoba-ku, sendai 980-8578, Japan


A new synthetic route to key intermediary phosphonium possessing a P3 phosphazene framework was developed. The reaction of the obtained intermediary phosphonium with chiral diamine, (1S,2S)-1,2-diphenyl-1,2-ethanediamine, resulted in the formation of 18-membered macrocyclic bisphosphazenium, the structure of which was verified by single-crystal X-ray diffraction analysis. The macrocyclic bisphosphazenium showed potential application as a chiral anion receptor and a chiral template in asymmetric catalysis.

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Short Paper | Special issue | Vol 90, No. 2, 2015, pp. 1405 - 1418
Published online: 11th September, 2014
DOI: 10.3987/COM-14-S(K)99
Solution-Phase-Peptide Synthesis without Purification of Column Chromatography and Recrystallization by Protecting Amino Acid Esters with Phosphinyl Chloride

Guanghui An, Wei Zhou, Xiaokang Xu, Yi Pan, and Guigen Li*

*Department of Chemistry & Biochemistry, Texas Tech University, Lubbock, TX 79409-1061, U.S.A.


Biphenyl phosphinyl chloride (Bpp-Cl) has been successfully applied for the amino acid GAP (Group-Assisted Purification) protection. The resulting N-protected amino acid esters have been readily converted into the corresponding amino acids and peptides through GAP operation. Biphalin, enkephalin derivatives and the fragments of surfaxin have also been synthesized via GAP work-up by avoiding column chromatography. The GAP protecting group (Bpp) can be recovered and can implement the former phosphonyl groups in peptide synthesis.

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Short Paper | Special issue | Vol 90, No. 2, 2015, pp. 1419 - 1432
Published online: 14th October, 2014
DOI: 10.3987/COM-14-S(K)103
Stereoselective Aza-Henry Reaction of Chiral tert-Butanesulfinyl Imines with Methyl or Ethyl 4-Nitrobutanoate: Easy Access to Enantioenriched 6-Substituted Piperidine-2,5-diones

M. Jesús García-Muñoz, Francisco Foubelo,* and Miguel Yus*

*Department of Organic Chemistry, Faculty of Sciences and Institute of Organic Synthesis (ISO), University of Alicante, P.O. Box 99, 03080 Alicante, Spain


The base-catalyzed addition of 4-nitrobutanoates 6 to N-tert-butanesulfinyl imines 8 under solvent-free reaction conditions proceeded with high face diastereoselectivity. The resulting β-nitroamine derivatives 9 were easily transformed into 6-substituted piperidine-2,5-diones 11 upon removal of the sulfinyl group with concomitant δ-lactam formation and functional group transformation under Nef reaction conditions.

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55 data found. 31 - 55 listedFirst Previous