Letters in Organic Chemistry

ISSN: 1570-1786

Letters in Organic Chemistry
Volume 3, Number 7, July 2006

Highlights in Organic Chemistry

Recent Advances in the Field of Peptide Nucleic Acids Pp. 495-503

Nicola M. Howarth Since their development, peptide nucleic acids (PNAs) have attracted much attention as potential pharmacological regulators of gene expression. This highlight reviews the most recent reports on the synthesis and hybridisation properties of PNA analogues, which have been designed to address some of the limitations associated with conventional PNAs.

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Letters in Organic Chemistry

Rapid Access to Enantiomerically Pure 3,6-Anhydro-2-deoxy-7-phenylglyconolactones. Synthesis of Diastereoisomers of (+)-Goniofufurone Pp. 504-509

Cristhian Sartillo-Meléndez, Silvano Cruz-Gregorio, Leticia Quintero & Fernando Sartillo-Piscil A simple stereocontrolled synthesis of diastereoisomers of (+)-goniofufurone has been developed. This synthesis, is capable of providing the compounds in substantial quantities.

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Intramolecular Aromatic Substitutions of the Imidazol-5-yl Radical to form Tricyclic Imidazo[5,1-a] Heterocycles Pp. 510-513

Fawaz Aldabbagh & Mairéad A. Clyne Imidazol-5-yl radical cyclizations using both metal hydride/AIBN and photochemical conditions to give imidazo[5,1-a]isoindole, imidazo[5,1-a]isoquinoline and imidazo[5,1-a]benzazepine are described.

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Tagging of Phosphopeptides by Phosphate Elimination and Michael Addition: The Effect of Nearest Neighbors on the Reaction Kinetics Pp. 514-518

Kati Mattila, Mikko Ora & Harri Lönnberg Kinetics of the base-catalyzed elimination of the phosphate group from short phosphoserinyl peptides and subsequent addition of 2-mercaptoethanol to the dehydroalaninyl residue has been studied. Neighboring side-chain-functionalized residues do not markedly interfere the reaction, resulting in rate variation of less than one order of magnitude.

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Synthesis and Biological Evaluation of Spirostanes Including Butyrolactone Moieties Pp. 519-522

Orlando Pando, Daniel G. Rivera, Francisco Coll, Vivian Leliebre-Lara, Odette Concepción & Carlos S. Pérez Four new spirostanes functionalized with the butyrolactone moiety were efficiently synthesized and submitted to preliminary biological tests. Two butyrolactones showed a promising plant growth-promoting activity which renders them good candidates for further biological studies.

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Iodine Catalyzed One-Pot Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones Under Ultrasound Irradiation Pp. 523-525

Jian-Sen Wang, Ji-Tai Li & Zhi-Ping Lin The Biginelli reaction efficiently catalyzed using commercially available iodine as a catalyst can afford the 3,4-dihydropyrimi din-2(1H)-ones in high yields under ultrasound irradiation.

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Oxepin- and Spiro-Annulation of 2-Pyridone in Conjunction with Claisen Rearrangement and Ruthenium Carbene Complex Mediated Enyne Metathesis Pp. 526-529

Krishna C. Majumdar, Habibur Rahaman & Brindaban Roy A facile synthesis of substituted oxepin and spirocyclic pyridone derivatives is described by enyne metathesis.

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Easy and Efficient Procedure for Preparation of Symmetric Organic Carbonates in Ionic Liquid Pp. 530-533

Laura Goracci, Lucia Brinchi, Raimondo Germani & Gianfranco Savelli Tributylmethylammonium methanesulfonate salt has been used as efficient medium for the synthesis of symmetric organic carbonates by alkylation of potassium carbonate.

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The Influence of Base on Regioselectivity of 5-Substituted Uracils Addition to Michael Acceptors Pp. 534-538

Slawomir Boncel & Krzysztof Walczak Michael type addition reaction of 5-substituted uracil derivatives to methyl acrylate and acrylonitrile has been studied. The regioselectivity of adducts has been observed due to the 5-substituent present in uracil ring and applied base.

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Design and Synthesis of Small Libraries of Peptidomimetics Based on a Thiazolidine Moiety Pp. 539-545

Pietro Campiglia, Isabel Gomez-Monterrey, Alfonso Carotenuto, Teresa Lama, Maria V. Diurno, Alessia Bertamino, Orazio Mazzoni, Marina Sala, Ettore Novellino & Paolo Grieco A short and general synthesis for the preparation of two series of conformationally constrained building block has been elaborated starting from amino acids.

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An Efficient Synthesis of 3-Benzyl-2H-Chromenes as Potential Antipicornavirus Agents Pp. 546-548

Nicoletta Desideri The synthesis of substituted 3-benzyl-2H-chromenes, designed as potential inhibitors of picornavirus infections, has been achieved by a new efficient three-step method starting from the O-alkylation of the appropriate 2-(hydroxymethyl)phenols with 1-bromo-3-phenylpropan-2-ones.

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Access to Chiral N-Substituted 1,4-Dihydropyridines Through the One-Pot Domino Michael-Azacyclization Process Pp. 549-553

N. Monnier-Benoit, I. Jabin & P. Netchitaïlo The one-pot domino Michael-azacyclization process was applied to the synthesis of chiral N-substituted 1,4-dihydropyridines starting from chiral enaminoesters and alkylidene malonate olefins or α,β-ethylenic aldehydes.

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Ceric Ammonium Nitrate: Novel and Robust Acetylating Catalyst Pp. 554-557

Sirajud D. Khaja & Jun Xue A simple and efficient acetylation protocol catalyzed by ceric ammonium nitrate has been devised. The reaction is fast and smooth producing acetates in excellent yields.

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Base-Promoted Reactions in Ionic Liquid Solvent: Synthesis of Butenolides Pp. 558-559

Didier Villemin, Bachir Mostefa-Kara, Nathalie Bar, Nouredine Choukchou-Braham, Nawel Cheikh, Amel Benmeddah, Hassan Hazimeh & Chawki Ziani-Cherif Synthesis of 4-methyl-5,5-dialkyl-2-oxo-2,5-dihydrofuran-3-carbonitriles is reported herein, using potassium carbonate as a base in an ionic liquid (BMIM, BF4) as solvent. The system ionic liquid and base can be recovered and reused.

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Viehe’s Salt in a Novel One Pot Synthesis of Azolo[1,2-a]Pyrimidines Pp. 560-563

Alexander S. Kiselyov & Leon Smith We have developed a practical procedure for the synthesis of polyfunctional azolo[1,5-a]pyrimidines via the reactive species generated in situ from N-substituted lactams and Viehe's salt. A short reaction sequence, good yields of title compounds (55-81%), as well as their ready isolation, and purification are the distinct advantages of the reported protocol.

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Electron-Transfer Reduction of Butyryloxymethyloxirane with Alkalide K, K+(15-crown-5)2Pp. 564-566

Zbigniew Grobelny, Andrzej Stolarzewicz, Marcin & Adalbert Maercker The reduction of butyryloxymethyloxirane with alkalide K, K+(15-crown-5)2 proceeds via the corresponding radical anion, which decomposes by the alkyl-oxygen bond cleavage or dimerizes. The comparison with alkyl glycidates shows that the position of the ester group in the substituent influences the reaction mechanism.

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Synthesis of 2-Diphenylphosphinoyl-2’-Halo Biphenyls Via Suzuki-Miyaura Coupling as Possible Route to Non-Symmetric Biphenyl Phosphines Pp. 567-570

Daniele Vinci, Xiaofeng Wu, Nuno M. Mateus, Ourida Saidi & Jianliang Xiao 2-Diphenylphosphinoyl-2’-halobiphenyls, precursors to important biphenyl phosphine ligands, could be accessed by Suzuki-Miyaura coupling; but the reaction was not as straight as might be expected.

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