Aza-Diels–Alder reaction between N-aryl-1-oxo-1H-isoindolium ions and tert-enamides: Steric effects on reaction outcome

• Amitabh Jha,
• Ting-Yi Chou,
• Zainab ALJaroudi,
• Bobby D. Ellis and
• T. Stanley Cameron

Beilstein J. Org. Chem. 2014, 10, 848–857, doi:10.3762/bjoc.10.81

• been studied. In continuation of our efforts on the development of novel synthetic methodologies [27][28][29][30][31][32][33][34][35][36], we report herein a systematic study of steric and electronic effects of aryl substituents leading to substituted 6,6a-dihydroisoindolo[2,1-a]quinolin-11(5H)-ones

An oxidative amidation and heterocyclization approach for the synthesis of β-carbolines and dihydroeudistomin Y

• Suresh Babu Meruva,
• Akula Raghunadh,
• Raghavendra Rao Kamaraju,
• U. K. Syam Kumar and
• P. K. Dubey

Beilstein J. Org. Chem. 2014, 10, 471–480, doi:10.3762/bjoc.10.45

• -carbolines or dihydroeudistomin. The previously developed synthetic methodologies in our laboratory [19][20][21][22][23][24] were utilized for the synthesis of eudistomin Y (6) and its analogues The disconnection approach employed in the synthesis of 1-benzoyl-β-carboline is described in Scheme 1

Synthesis and stereochemical assignments of diastereomeric Ni(II) complexes of glycine Schiff base with (R)-2-(N-{2-[N-alkyl-N-(1-phenylethyl)amino]acetyl}amino)benzophenone; a case of configurationally stable stereogenic nitrogen

• Hiroki Moriwaki,
• Daniel Resch,
• Hengguang Li,
• Iwao Ojima,
• Ryosuke Takeda,
• José Luis Aceña and
• Vadim A. Soloshonok

Beilstein J. Org. Chem. 2014, 10, 442–448, doi:10.3762/bjoc.10.41

• currently available methodologies [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30]; however, the chemistry of α-AAs continues to evolve [31][32][33][34][35][36][37][38]. Many of the reported synthetic methodologies have shown preference for

Diversity-oriented synthesis of dihydrobenzoxazepinones by coupling the Ugi multicomponent reaction with a Mitsunobu cyclization

• Lisa Moni,
• Luca Banfi,
• Andrea Basso,
• Alice Brambilla and
• Renata Riva

Beilstein J. Org. Chem. 2014, 10, 209–212, doi:10.3762/bjoc.10.16

• Lorenzo Giardini and Sara Piano for preliminary exploratory experiments, Andrea Armirotti and Martina Spallarossa for HRMS, PRIN 2009 ("Synthetic Methodologies for Generation of Biologically Relevant Molecular Diversity") and the University of Genova for funding.

New developments in gold-catalyzed manipulation of inactivated alkenes

• Michel Chiarucci and
• Marco Bandini

Beilstein J. Org. Chem. 2013, 9, 2586–2614, doi:10.3762/bjoc.9.294

• . Cooperative [Au(I)]/menthol catalysis for the enantioselective intramolecular hydroamination of dienes. Acknowledgements Acknowledgment is made to Progetto FIRB “Futuro in Ricerca” Innovative sustainable synthetic methodologies for C–H activation processes, (MIUR, Rome) and the Università di Bologna.

An overview of the synthetic routes to the best selling drugs containing 6-membered heterocycles

• Marcus Baumann and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2013, 9, 2265–2319, doi:10.3762/bjoc.9.265

• outlay [5]. As a result pharmaceutical companies are constantly seeking ways to accelerate this development process by adopting new synthetic methodologies and enabling technologies in order to profitably generate new medications for both old and new targets [6]. By reviewing the synthetic routes used to

Straightforward synthesis of a tetrasaccharide repeating unit corresponding to the O-antigen of Escherichia coli O16

• Manas Jana and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2013, 9, 1757–1762, doi:10.3762/bjoc.9.203

• summary, a straightforward synthetic strategy was developed for the synthesis of the tetrasaccharide 1 as its p-methoxyphenyl glycoside corresponding to the O-antigen of E. coli O16. The target compound was synthesized by using a minimum number of steps and by applying recently developed elegant synthetic

• methodologies. Both the yields of the protecting group manipulations and the stereoselectivity of the glycosylation reactions were excellent. Experimental General methods are similar as described in an earlier report [21]. p-Methoxyphenyl (2-O-acetyl-4-O-benzyl-α-L-rhamnopyranosyl)-(1→3)-2-azido-4,6-O

Organocatalyzed enantioselective desymmetrization of aziridines and epoxides

• Ping-An Wang

Beilstein J. Org. Chem. 2013, 9, 1677–1695, doi:10.3762/bjoc.9.192

• desymmetrization of meso-aziridines and meso-epoxides. Undoubtedly, these synthetic methodologies will continue to demonstrate their versatile utilities in organic synthesis. However, there are some difficulties that should be pointed out. Organocatalysts for the enantioselective desymmetrization of meso

Coupling of C-nitro-NH-azoles with arylboronic acids. A route to N-aryl-C-nitroazoles

• Marta K. Kurpet,
• Aleksandra Dąbrowska,
• Małgorzata M. Jarosz,
• Katarzyna Kajewska-Kania,
• Nikodem Kuźnik and
• Jerzy W. Suwiński

Beilstein J. Org. Chem. 2013, 9, 1517–1525, doi:10.3762/bjoc.9.173

• containing a base, both of which are necessary for providing good yields of the products. The method represents an important supplement to the synthetic methodologies for the preparation of N-aryl-C-nitroazoles and can be successfully applied to the synthesis of a series of diverse C-nitroazoles

Amyloid-β probes: Review of structure–activity and brain-kinetics relationships

• Todd J. Eckroat,
• Abdelrahman S. Mayhoub and
• Sylvie Garneau-Tsodikova

Beilstein J. Org. Chem. 2013, 9, 1012–1044, doi:10.3762/bjoc.9.116

• efforts to develop chemical probes to detect pathophysiological hallmarks of AD, such as amyloid-β plaques, for diagnosis and monitoring of therapeutic efficacy. This review provides a survey of chemical probes developed to date for AD with emphasis on synthetic methodologies and structure–activity

Alternaric acid: formal synthesis and related studies

• Michael C. Slade and
• Jeffrey S. Johnson

Beilstein J. Org. Chem. 2013, 9, 166–172, doi:10.3762/bjoc.9.19

• endeavors, both in natural-product synthesis and synthetic methodologies [20]. Key to their use in a variety of contexts is the ability of silyl glyoxylates to function as linchpin synthons for geminal coupling of nucleophile/electrophile pairs at a glycolic acid subunit (Scheme 1A), which allows the rapid

Organocatalytic tandem Michael addition reactions: A powerful access to the enantioselective synthesis of functionalized chromenes, thiochromenes and 1,2-dihydroquinolines

• Chittaranjan Bhanja,
• Satyaban Jena,
• Sabita Nayak and
• Seetaram Mohapatra

Beilstein J. Org. Chem. 2012, 8, 1668–1694, doi:10.3762/bjoc.8.191

• ]. Therefore, synthetic methodologies allowing rapid access to these heterocycles in optically enriched form are highly desirable in organic synthesis and chemical biology/medicinal chemistry. In the past few years very promising progress has been made in this intriguing area, and among the advances

Chiral multifunctional thiourea-phosphine catalyzed asymmetric [3 + 2] annulation of Morita–Baylis–Hillman carbonates with maleimides

• Hong-Ping Deng,
• De Wang,
• Yin Wei and
• Min Shi

Beilstein J. Org. Chem. 2012, 8, 1098–1104, doi:10.3762/bjoc.8.121

• five stereocenters under mild conditions, which was difficult to construct by other synthetic methodologies. Current efforts are in progress to apply this new methodology to synthesize biologically active products. Experimental General procedure for asymmetric [3 + 2] annulation Under an argon

Synthetic glycopeptides and glycoproteins with applications in biological research

• Ulrika Westerlind

Beilstein J. Org. Chem. 2012, 8, 804–818, doi:10.3762/bjoc.8.90

• ) to LecA compared with D-galactose [148]. Similar to the LecB inhibitor FD2, complete inhibition of biofilm formation was observed. Conclusions Recent developments of synthetic methodologies have enabled the preparation of complex glycopeptides and glycoproteins. The availability of structurally

Catalyst-free and solvent-free Michael addition of 1,3-dicarbonyl compounds to nitroalkenes by a grinding method

• Zong-Bo Xie,
• Na Wang,
• Ming-Yu Wu,
• Ting He,
• Zhang-Gao Le and
• Xiao-Qi Yu

Beilstein J. Org. Chem. 2012, 8, 534–538, doi:10.3762/bjoc.8.61

• yields by a grinding method under catalyst- and solvent-free conditions. Keywords: catalyst-free; grinding; Michael addition; solvent-free; Introduction Nowadays, chemists are vigorously taking on the challenge of developing green synthetic methodologies to meet the criteria of sustainable

Gold(I)-catalyzed synthesis of γ-vinylbutyrolactones by intramolecular oxaallylic alkylation with alcohols

• Michel Chiarucci,
• Mirko Locritani,
• Gianpiero Cera and
• Marco Bandini

Beilstein J. Org. Chem. 2011, 7, 1198–1204, doi:10.3762/bjoc.7.139

• the gold-catalyzed intramolecular allylation of 1.a Supporting Information Supporting Information File 172: Experimental details and characterization of the synthesized compounds. Acknowledgment Acknowledgment is made to Progetto FIRB “Futuro in Ricerca” Innovative sustainable synthetic

• methodologies for C–H activation processes (MIUR, Rome), Università di Bologna.

Triazole–Au(I) complex as chemoselective catalyst in promoting propargyl ester rearrangements

• Dawei Wang,
• Yanwei Zhang,
• Rong Cai and
• Xiaodong Shi

Beilstein J. Org. Chem. 2011, 7, 1014–1020, doi:10.3762/bjoc.7.115

• application of the allene-carbonates and allene-carbamates as building blocks for development of new synthetic methodologies is currently underway in our group. Chemoselective activation of alkyne over allene by the TA–Au catalysts. The counter ligands, an important factor in Au(I) catalysis. The challenge of

Synthesis of novel 5-alkyl/aryl/heteroaryl substituted diethyl 3,4-dihydro-2H-pyrrole-4,4-dicarboxylates by aziridine ring expansion of 2-[(aziridin-1-yl)-1-alkyl/aryl/heteroaryl-methylene]malonic acid diethyl esters

• Satish S. More,
• T. Krishna Mohan,
• Y. Sateesh Kumar,
• U. K. Syam Kumar and
• Navin B. Patel

Beilstein J. Org. Chem. 2011, 7, 831–838, doi:10.3762/bjoc.7.95

• use for the development of novel synthetic methodologies and for various organic transformations. Recently, the ring opening of N-vinyl substituted aziridines by selenide nucleophiles to furnish functionalized open chain compounds has been described [23]. N-vinyl substituted aziridines can be

Surfactant catalyzed convenient and greener synthesis of tetrahydrobenzo[a]xanthene-11-ones at ambient temperature

• Pravin V. Shinde,
• Amol H. Kategaonkar,
• Bapurao B. Shingate and
• Murlidhar S. Shingare

Beilstein J. Org. Chem. 2011, 7, 53–58, doi:10.3762/bjoc.7.9

• ]xanthen-11-one using tetradecyltrimethylammonium bromide (TTAB) at room temperature in water is described. Keywords: green chemistry; in-water synthesis; surfactant; tetradecyltrimethylammonium bromide (TTAB); xanthene; Introduction The development of novel synthetic methodologies to facilitate the

Novel tetracyclic structures from the synthesis of thiolactone-isatin hybrids

• Renate Hazel Hans,
• Hong Su and
• Kelly Chibale

Beilstein J. Org. Chem. 2010, 6, No. 78, doi:10.3762/bjoc.6.78

• against the condensing enzymes of type II fatty acid synthesis which operate in a number of pathogenic organisms [6][7][8]. Synthetic methodologies for 1 and a series of racemic and enantiopure thiolactomycin-based analogues have been reported [9][10][11][12][13][14][15][16]. Of particular interest to

(Pseudo)amide-linked oligosaccharide mimetics: molecular recognition and supramolecular properties

• José L. Jiménez Blanco,
• Fernando Ortega-Caballero,
• Carmen Ortiz Mellet and
• José M. García Fernández

Beilstein J. Org. Chem. 2010, 6, No. 20, doi:10.3762/bjoc.6.20

• aminocyclopentitol rings. Trehazolin is a potent trehalase inhibitor in which an aminocyclopentitol ring replaces the glucopyranosyl cation postulated as an intermediate in the enzymatic hydrolysis of α,α-trehalose. Although several synthetic methodologies had successfully been applied to prepare this inhibitor

• synthetic methodologies for thioureido and ureido glycooligomers have made thus enabling the preparation of virtually any oligomeric structure (linear, branched, dendritic and cyclic). The secondary structures adopted by these pseudooligosaccharides have been extensively studied by current NMR and molecular

Synthesis of a new class of aminocyclitol analogues with the conduramine D-2 configuration

• Latif Kelebekli,
• Yunus Kara and
• Murat Celik

Beilstein J. Org. Chem. 2010, 6, No. 15, doi:10.3762/bjoc.6.15

• of carbohydrate mimetics, which can be potent inhibitors of glycosidase (1–4) [11][12][13][14][15][16], we have developed a method for rapid entry to these compounds. Antibiotics containing an aminocyclitol unit have stimulated the development of synthetic methodologies [16] in the search for

A divergent asymmetric approach to aza-spiropyran derivative and (1S,8aR)-1-hydroxyindolizidine

• Jian-Feng Zheng,
• Wen Chen,
• Su-Yu Huang,
• Jian-Liang Ye and
• Pei-Qiang Huang

Beilstein J. Org. Chem. 2007, 3, No. 41, doi:10.1186/1860-5397-3-41

• of enantiomeric malimide-based synthetic methodologies, [35][36][37][38] we now report concise and highly diastereoselective syntheses of an aza-spiropyran derivative 7 and (1S,8aR)-1-hydroxyindolizidine (ent-3). Results and discussion Previously, we have shown that the addition of Grignard reagents

High stereoselectivity on low temperature Diels- Alder reactions

• Luiz Carlos da Silva Filho,
• Valdemar Lacerda Júnior,
• Mauricio Gomes Constantino,
• Gil Valdo José da Silva and
• Paulo Roberto Invernize

Beilstein J. Org. Chem. 2005, 1, No. 14, doi:10.1186/1860-5397-1-14

• studies [8][9][10][11] that demonstrated how large the influence of the Lewis acid can have on several aspects of the reactions. As part of our research work on synthetic methodologies using niobium pentachloride in a variety of reactions [12][13][14], we have recently started an investigation on