Strategies in the synthesis of dibenzo[b,f]heteropines

• David I. H. Maier,
• Barend C. B. Bezuidenhoudt and
• Charlene Marais

Beilstein J. Org. Chem. 2023, 19, 700–718, doi:10.3762/bjoc.19.51

• thioethers from aryl halides and triflates through palladium catalysis [50][51]. Scheme 10 provides a retrosynthesis of amination in the synthesis of dibenzo[b,f]azepine 45 as an example. Arnold et al. [30] reported an excellent method for the convergent synthesis of variable sized dibenzo-fused heterocycles

Derivatives of benzo-1,4-thiazine-3-carboxylic acid and the corresponding amino acid conjugates

• Péter Kisszékelyi,
• Tibor Peňaška,
• Klára Stankovianska,
• Mária Mečiarová and
• Radovan Šebesta

Beilstein J. Org. Chem. 2022, 18, 1195–1202, doi:10.3762/bjoc.18.124

• the original convergent synthesis plan. Instead of the classical amide coupling, bromo derivative Int1 should allow the formation of the benzothiazine ring as the final step. As an α-halocarbonyl compound, we tried to prepare Int1 through the coupling of bromopyruvic acid and ester, respectively, with

Synthesis of protected precursors of chitin oligosaccharides by electrochemical polyglycosylation of thioglycosides

• Md Azadur Rahman,
• Kana Kuroda,
• Hirofumi Endo,
• Norihiko Sasaki,
• Tomoaki Hamada,
• Hiraku Sakai and
• Toshiki Nokami

Beilstein J. Org. Chem. 2022, 18, 1133–1139, doi:10.3762/bjoc.18.117

• from natural sources or by synthesis via chemical glycosylation [2]. Total syntheses of chitin and chitosan oligosaccharides based on conventional chemical glycosylation of protected monosaccharides as building blocks have already been reported. Convergent synthesis using oligosaccharide building

Progress and challenges in the synthesis of sequence controlled polysaccharides

• Giulio Fittolani,
• Theodore Tyrikos-Ergas,
• Denisa Vargová,
• Manishkumar A. Chaube and
• Martina Delbianco

Beilstein J. Org. Chem. 2021, 17, 1981–2025, doi:10.3762/bjoc.17.129

Double-headed nucleosides: Synthesis and applications

• Vineet Verma,
• Jyotirmoy Maity,
• Vipin K. Maikhuri,
• Ritika Sharma,
• Himal K. Ganguly and
• Ashok K. Prasad

Beilstein J. Org. Chem. 2021, 17, 1392–1439, doi:10.3762/bjoc.17.98

• . The convergent synthesis of the double-headed nucleosides was achieved from uridine, which was first converted to the 3′,5′-(1,1,3,3-tetraisopropyldisiloxan-1,3-diyl)-protected (TIPDS) ketonucleoside 1 following a standard procedure [40]. The subsequent Corey–Chaykovsky epoxidation [41] of 2

Synthetic strategies of phosphonodepsipeptides

• Jiaxi Xu

Beilstein J. Org. Chem. 2021, 17, 461–484, doi:10.3762/bjoc.17.41

• reaction directly from the simple and commercially available chemicals, benzyl carbamate (154), aldehydes 155, and methyl dichlorophosphite (156), followed by the alcoholysis with the hydroxy esters 157. The current strategy is a highly efficient and convergent synthesis of phosphonodepsipeptides that does

Regioselective chemoenzymatic syntheses of ferulate conjugates as chromogenic substrates for feruloyl esterases

• Olga Gherbovet,
• Fernando Ferreira,
• Apolline Clément,
• Mélanie Ragon,
• Julien Durand,
• Sophie Bozonnet,
• Michael J. O'Donohue and
• Régis Fauré

Beilstein J. Org. Chem. 2021, 17, 325–333, doi:10.3762/bjoc.17.30

• ferulate to the primary hydroxy group of α‐ʟ‐arabinofuranosides. Moreover, a novel feruloylated 4-nitrocatechol-1-yl-substituted butanetriol analog, containing a cleavable hydroxylated linker, was also synthesized in 32% overall yield in 3 steps (convergent synthesis). The latter route combined the

• in a high yield of 94%. Accordingly, the synthesis of the chromogenic ferulate 12 was achieved in 32% overall yield in 3 steps from commercial reactants (convergent synthesis using a slight excess of the synthesized vinyl ferulate 2) and without the requirement to perform a final deprotection. As

• alcohols and polyhydroxylated compounds. Three compounds suitable for the detection and/or characterization of Fae activity were synthesized in a straightforward protocol that holds the potential to greatly reduce the cost of the substrates 1a and 1b. Moreover, the enzyme-driven convergent synthesis of 12

Combining enyne metathesis with long-established organic transformations: a powerful strategy for the sustainable synthesis of bioactive molecules

• Valerian Dragutan,
• Ileana Dragutan,
• Albert Demonceau and
• Lionel Delaude

Beilstein J. Org. Chem. 2020, 16, 738–755, doi:10.3762/bjoc.16.68

• ] accomplished the convergent synthesis of des-epoxy-amphidinolide N (5) in 33 total steps (22 longest linear). To this end, after three generations of synthetic attempts, they succeeded joining the northern and southern fragments of des-epoxy-amphidinolide N, both endowed with a considerable level of structural

• -metathesis, and a one-pot, two-step stereoselective conjugated allylic alcohol substitution (Scheme 26). It should be emphasized that in this convergent synthesis of (−)-exiguolide, the authors achieved a rigorous stereocontrol of both the exocyclic and endocyclic double bond geometries, as well as the

Chemical synthesis of tripeptide thioesters for the biotechnological incorporation into the myxobacterial secondary metabolite argyrin via mutasynthesis

• David C. B. Siebert,
• Roman Sommer,
• Domen Pogorevc,
• Michael Hoffmann,
• Silke C. Wenzel,
• Rolf Müller and
• Alexander Titz

Beilstein J. Org. Chem. 2019, 15, 2922–2929, doi:10.3762/bjoc.15.286

• sarcosine moiety could be obtained. To overcome the high reactivity of the Dha moiety towards nucleophiles, we engaged in an alternative synthetic strategy towards the tripeptide thioester carrying the native sequence ᴅ-Ala-Dha-Sar by designing a convergent synthesis to mutasynthon 14 (Scheme 2). First, Boc

• desired thioester probably due to the higher reactivity of the Michael acceptor system. Revision of the synthetic approach into a convergent synthesis with initial formation of the thioester at the amino acid level and subsequent coupling to a dipeptide finally yielded the desired mutasynthon carrying the

Norbornadiene-functionalized triazatriangulenium and trioxatriangulenium platforms

• Roland Löw,
• Talina Rusch,
• Tobias Moje,
• Fynn Röhricht,
• Olaf M. Magnussen and
• Rainer Herges

Beilstein J. Org. Chem. 2019, 15, 1815–1821, doi:10.3762/bjoc.15.175

• obtained in a convergent synthesis (Scheme 2). Boronic ester 9 was synthesized as described in the literature [15]. In a Suzuki cross-coupling reaction norbornadiene 4 was coupled with 9 to the extended norbornadiene 10 (38%), which was attached to the TATA platform 6 to yield the extended norbornadiene

Convergent synthesis of the pentasaccharide repeating unit of the biofilms produced by Klebsiella pneumoniae

• Arin Gucchait,
• Angana Ghosh and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2019, 15, 431–436, doi:10.3762/bjoc.15.37

• the biofilm producing polysaccharide secreted by K. pneumoniae. A convergent synthesis of a pentasaccharide as its 2-aminoethyl glycoside containing a β-D-mannosidic moiety and a α-D-glucuronic acid moiety is presented herein. The presence of a 2-aminoethyl group at the reducing end of the

• convergent synthesis of a pentasaccharide corresponding to the repeating unit of the biofilm producing polysaccharide secreted by K. pneumoniae as its 2-aminoethyl glycoside has been achieved in good yield. The noteworthy points of the synthetic strategy include stereoselective construction of a β-D

Design, synthesis and structure of novel G-2 melamine-based dendrimers incorporating 4-(n-octyloxy)aniline as a peripheral unit

• Cristina Morar,
• Pedro Lameiras,
• Attila Bende,
• Gabriel Katona,
• Emese Gál and
• Mircea Darabantu

Beilstein J. Org. Chem. 2018, 14, 1704–1722, doi:10.3762/bjoc.14.145

• the G-1 dendritic branches to the m-trivalent core. Conclusion Starting from 4-(n-octyloxy)aniline, the five-step orthogonal convergent synthesis of a new seven terms series of G-2 melamine based-dendrimers was achieved in overall yields ranging between 29 and 79%. By means of DFT calculation in

Recent advances in synthetic approaches for medicinal chemistry of C-nucleosides

• Kartik Temburnikar and
• Katherine L. Seley-Radtke

Beilstein J. Org. Chem. 2018, 14, 772–785, doi:10.3762/bjoc.14.65

• maneuver stereochemistry as well as to incorporate structural modifications. In this review, we describe recent reports on the modular synthesis of C-nucleosides with a focus on D-ribonolactone and sugar modifications that have resulted in potent lead molecules. Keywords: C-nucleosides; convergent

• synthesis; modular synthesis; Introduction Nucleic acids form the genetic blueprint for all living organisms and are involved with a wide range of cellular functions [1][2][3][4][5][6][7][8][9]. Modifications to their chemical structure can have profound effects on structure and function of enzymes, cells

Recent developments in the asymmetric Reformatsky-type reaction

• Hélène Pellissier

Beilstein J. Org. Chem. 2018, 14, 325–344, doi:10.3762/bjoc.14.21

• /cholecyctokinin-B receptor antagonist AG-041R starting from Reformatsky chiral product 33a. Earlier in 2015, Ley et al. reported an efficient synthesis of a precursor of the neprilysin inhibitor sacubitril based on a zinc-mediated aza-Reformatsky-type reaction [31]. Indeed, this convergent synthesis featured a

Enzymatic separation of epimeric 4-C-hydroxymethylated furanosugars: Synthesis of bicyclic nucleosides

• Neha Rana,
• Manish Kumar,
• Vinod Khatri,
• Jyotirmoy Maity and
• Ashok K. Prasad

Beilstein J. Org. Chem. 2017, 13, 2078–2086, doi:10.3762/bjoc.13.205

• acetylation, has been confirmed by an X-ray study on their corresponding 4-C-p-toluenesulfonyloxymethyl derivatives. Furthermore, the two separated epimers were used for the convergent synthesis of two different types of bicyclic nucleosides, which confirms their synthetic utility. Keywords

• mixture of xylo- and ribofuranosides. Separated epimers were further used as sugar precursors for the convergent synthesis of two different types of bicyclic nucleosides which are monomers of oxetano- and locked nucleic acids of medicinal importance [16]. Results and Discussion 4-C-Hydroxymethyl-1,2-O

• ). Two tosylated sugar derivatives 5 and 10 have been successfully used for the convergent synthesis of 3′-O,4′-C-methyleneuridine (9) and 2′-O,4′-C-methylene-xylouridine (14) to illustrate the usefulness of the trihydroxyribo-/xylofuranose sugar derivatives separated by an enzymatic acetylation

Synthesis of oligonucleotides on a soluble support

• Harri Lönnberg

Beilstein J. Org. Chem. 2017, 13, 1368–1387, doi:10.3762/bjoc.13.134

• , impressive examples of classical convergent synthesis [31][32][33][34] and exploitation of solid-supported reagents in solution [35][36] have been reported. The present review, however, surveys only the progress of ON synthesis on a soluble support. Review Synthesis of oligodeoxyribonucleotides by

Stereodynamic tetrahydrobiisoindole “NU-BIPHEP(O)”s: functionalization, rotational barriers and non-covalent interactions

• Golo Storch,
• Sebastian Pallmann,
• Frank Rominger and
• Oliver Trapp

Beilstein J. Org. Chem. 2016, 12, 1453–1458, doi:10.3762/bjoc.12.141

• phases [22]. However, introduction of functional groups which enable a modular derivatization approach is often hampered by long and tedious synthetic procedures. Doherty et al. reported a rhodium catalyzed double [2 + 2 + 2] cycloaddition strategy for a convergent synthesis of “NU-BIPHEP”s [23]. In this

Synthesis of a hexasaccharide partial sequence of hyaluronan for click chemistry and more

• Marina Bantzi,
• Stephan Rigol and
• Athanassios Giannis

Beilstein J. Org. Chem. 2015, 11, 604–607, doi:10.3762/bjoc.11.67

• frame of a research project aiming the investigation of protein–GAG binding a convergent synthesis of a HA hexamer with a suitably modified aglycone is described herein. Results and Discussion The synthetic cascade to the desirable hexasaccharide 10 is presented in Scheme 1. Trichloroacetimidate 1 [20

Autonomous assembly of synthetic oligonucleotides built from an expanded DNA alphabet. Total synthesis of a gene encoding kanamycin resistance

• Kristen K. Merritt,
• Kevin M. Bradley,
• Daniel Hutter,
• Mariko F. Matsuura,
• Diane J. Rowold and
• Steven A. Benner

Beilstein J. Org. Chem. 2014, 10, 2348–2360, doi:10.3762/bjoc.10.245

• synthesis of complete genes, have followed a convergent assembly strategy. This was used for the first time for the total synthesis of genes encoding transfer RNA [5], but convergent synthesis is generally routine for the synthesis of natural products [6]. In the convergent synthesis of L-DNA, subsets of

• convergent synthesis after blunt-end ligation. The desired 1,135 base-pair target construct was recovered by PCR (see Supporting Information File 1, Figure S4). This process was, of course, not automated; it represented the same stepwise convergent assembly of L-DNA that has been reported previously [3][4][5

Convergent synthetic methodology for the construction of self-adjuvanting lipopeptide vaccines using a novel carbohydrate scaffold

• Vincent Fagan,
• Istvan Toth and
• Pavla Simerska

Beilstein J. Org. Chem. 2014, 10, 1741–1748, doi:10.3762/bjoc.10.181

• epitope. Synthesis of carbohydrate building block 1. (A) Lipidation of Fmoc-Lys-OH with lauroyl chloride: (B) Lipidation of Fmoc-Lys-OH with sulfonic-carboxylic anhydride. Convergent synthesis of self-adjuvanting vaccine candidate 10 consisting of lipidic adjuvanting moiety LLCP, carbohydrate carrier and

• four copies of J8 peptide epitope. Convergent synthesis of self-adjuvanting vaccine candidate 12 consisting of lipidic adjuvanting moiety LLCP, T-helper epitope, carbohydrate carrier and four copies of J8 B cell epitope. Supporting Information All experimental procedures are given. 1H, 13C, DEPT, COSY

Synthesis and solvodynamic diameter measurements of closely related mannodendrimers for the study of multivalent carbohydrate–protein interactions

• Yoann M. Chabre,
• Alex Papadopoulos,
• Alexandre A. Arnold and
• René Roy

Beilstein J. Org. Chem. 2014, 10, 1524–1535, doi:10.3762/bjoc.10.157

• core 10 and azide 3 to afford 9-mer 12. Divergent CuAAc synthesis of “extended” 9-mer 17 using phloroglucinol (13) as core, bromoacylated TRIS as linker and mannopyranosylazide 3. Convergent synthesis of further “extended” 9-mer 21 using mannosylated bromoacyl dendron 18 transformed into azide 19

Stereoselective synthesis of carbocyclic analogues of the nucleoside Q precursor (PreQ₀)

• Sabin Llona-Minguez and
• Simon P. Mackay

Beilstein J. Org. Chem. 2014, 10, 1333–1338, doi:10.3762/bjoc.10.135

• inhibitor library generation programme. Results and Discussion Our retrosynthetic approach introduces the diversity point at a late stage and takes advantage of the heterocyclic lactam present in PreQ0 after activation and subsequent nucleophilic aromatic substitution. This convergent synthesis allowed us

Human dendritic cell activation induced by a permannosylated dendron containing an antigenic GM₃-lactone mimetic

• Renato Ribeiro-Viana,
• Elena Bonechi,
• Javier Rojo,
• Clara Ballerini,
• Giuseppina Comito,
• Barbara Richichi and
• Cristina Nativi

Beilstein J. Org. Chem. 2014, 10, 1317–1324, doi:10.3762/bjoc.10.133

• strategies based on dendritic cells (DCs) armed with specific tumor antigens have been widely exploited due the properties of these immune cells in coordinating an innate and adaptive response. Here, we describe the convergent synthesis of the bifunctional multivalent glycodendron 5, which contains nine

• the convergent synthesis of the bifunctional multivalent glycodendron 5 (Scheme 1) and on human DC activation and related mixed-lymphocyte reaction (MLR) induced by the antigenic glycodendron 5. Results and Discussion Glycodendron 5 (Scheme 1) is a bifunctional compound containing nine residues of

• data gathered in the experiments outlined here we conclude that the maturation/stimulation of DCs is specifically linked to the presence of the mimetic antigen residue and not determined by the scaffold alone. Conclusion Here, we reported on the convergent synthesis of the ditopic multivalent

Convergent synthesis of a tetrasaccharide repeating unit of the O-specific polysaccharide from the cell wall lipopolysaccharide of Azospirillum brasilense strain Sp7

• Pintu Kumar Mandal,
• Debashis Dhara and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2014, 10, 293–299, doi:10.3762/bjoc.10.26

• -700054, India 10.3762/bjoc.10.26 Abstract A straightforward convergent synthesis has been carried out for the tetrasaccharide repeating unit of the O-specific cell wall lipopolysaccharide of the strain Sp7 of Azospirillum brasilense. The target tetrasaccharide has been synthesized from suitably

• summary, a straightforward and convergent synthesis of the tetrasaccharide 1 as its 2-aminoethyl glycoside corresponding to the O-specific polysaccharide of the LPS of A. brasilense strain Sp7 has been presented. The use of thioglycosides both as glycosyl donor and acceptor according to the concept of the

Total synthesis and biological evaluation of fluorinated cryptophycins

• Christine Weiß,
• Tobias Bogner,
• Benedikt Sammet and
• Norbert Sewald

Beilstein J. Org. Chem. 2012, 8, 2060–2066, doi:10.3762/bjoc.8.231

• pentafluorophenylalanine building block 26. Reagents and conditions: (a) pyridine, trichloroethanol, DCC, CH2Cl2, 0 °C, 20 h; (b) 1. TFA, rt, 2 h; 2. NEt3, acryloylchloride, CH2Cl2, 0 °C, 7 h. Convergent synthesis of the pentafluorinated cryptophycin 31. Reagents and conditions: (a) Grubbs II catalyst, CH2Cl2, reflux, 16