Synthesis of a novel category of pseudo-peptides using an Ugi three-component reaction of levulinic acid as bifunctional substrate, amines, and amino acid-based isocyanides

• Maryam Khalesi,
• Azim Ziyaei Halimehjani and
• Jürgen Martens

Beilstein J. Org. Chem. 2019, 15, 852–857, doi:10.3762/bjoc.15.82

• synthesis of a novel category of pseudo-peptides via intramolecular Ugi reaction of levulinic acid (4-oxopentanoic acid), aromatic and aliphatic amines, and amino acid-based isocyanides is reported. Levulinic acid was applied as a bifunctional substrate containing both carbonyl and acid moieties suitable

• for the Ugi reaction. This article provides a facile and convenient one-pot procedure for the synthesis of peptide-like heterocyclic molecules containing 2-pyrrolidone (γ-lactam), amide and ester functional groups with good to excellent yields. Keywords: amino acid-based isocyanides; levulinic acid

• Ugi condensation reaction in order to keep the multicomponent sequence as short as possible which makes it less complicated [13][14][15][16][17]. Levulinic acid or 4-oxopentanoic acid, is an organic compound which is classified as a ketoacid. It can be easily prepared in industrial scale and low price

Green synthesis of new chiral 1-(arylamino)imidazo[2,1-a]isoindole-2,5-diones from the corresponding α-amino acid arylhydrazides in aqueous medium

• Nadia Bouzayani,
• Jamil Kraїem,
• Sylvain Marque,
• Yakdhane Kacem,
• Abel Carlin-Sinclair,
• Jérôme Marrot and
• Béchir Ben Hassine

Beilstein J. Org. Chem. 2018, 14, 2923–2930, doi:10.3762/bjoc.14.271

• refluxing α-amino acid phenylhydrazides with levulinic acid in toluene led to the corresponding dihydro-1H-pyrrolo[1,2-a]imidazole-2,5-diones. These authors explained clearly the behavior of the solvent and its influence in the reaction. In addition, substituted 1-hydroxy-1H-imidazo[2,1-a]isoindole-2,5(3H

Total synthesis of a Streptococcus pneumoniae serotype 12F CPS repeating unit hexasaccharide

• Peter H. Seeberger,
• Claney L. Pereira and
• Subramanian Govindan

Beilstein J. Org. Chem. 2017, 13, 164–173, doi:10.3762/bjoc.13.19

• : trimethylsilyl trifluoromethanesulfonate. Structure of the S. pneumoniae serotype 12F capsular polysaccharide repeating unit [15]. Retrosynthetic analyses of the S. pneumoniae hexasaccharide 1. Attempted synthesis of mannosazide building block 15. Reagents and conditions: (a) levulinic acid, DCC, DMAP, CH2Cl2

Silica-supported sulfonic acids as recyclable catalyst for esterification of levulinic acid with stoichiometric amounts of alcohols

• Raimondo Maggi,
• N. Raveendran Shiju,
• Veronica Santacroce,
• Giovanni Maestri,
• Franca Bigi and
• Gadi Rothenberg

Beilstein J. Org. Chem. 2016, 12, 2173–2180, doi:10.3762/bjoc.12.207

• context, levulinic acid, which is easily obtained from cellulose, is valuable since it can be transformed into a variety of industrially relevant fine chemicals. Here we present a simple protocol for the selective esterification of levulinic acid using solid acid catalysts. Silica supported sulfonic acid

• , respectively. All of these polymers are the subject of many studies [5][6][7][8][9][10][11]. Levulinic acid (LA) is one of the most important platform chemicals as it is a versatile building block for a variety of value-added agrochemicals, fine chemicals and pharmaceutical intermediates [12][13] (Scheme 1

• , bottom). Moreover, it can be obtained from cellulose with relative ease and high selectivity (see Scheme 1, top) [14]. Levulinic acid esters are of particular interest for the chemical industry [12][13]. Their main current market is represented by the formulation of flavours and fragrances [15], although

Synthesis and reactivity of aliphatic sulfur pentafluorides from substituted (pentafluorosulfanyl)benzenes

• Norbert Vida,
• Jiří Václavík and
• Petr Beier

Beilstein J. Org. Chem. 2016, 12, 110–116, doi:10.3762/bjoc.12.12

• lactone 3 remained unaffected. At 80 °C the formation of levulinic acid derivative 18 was observed together with unidentified byproducts. Under elevated temperature (100 °C and above) the product of HF and SF4 elimination, (E)-4-oxopent-2-enoic acid (19) [28] formed (Scheme 7). In a preparative experiment

• using 85% H3PO4 at 100 °C, levulinic acid 18 was obtained in 14% yield. This result allowed us to propose that byproduct 5 observed during oxidation of SF5-anisoles and phenols could be formed from open-chain acids according to Scheme 7. Despite the lack of efficient synthetic protocols toward maleic

A versatile δ-aminolevulinic acid (ΑLA)-cyclodextrin bimodal conjugate-prodrug for PDT applications with the help of intracellular chemistry

• Chrysie Aggelidou,
• Theodossis A. Theodossiou,
• Antonio Ricardo Gonçalves,
• Mariza Lampropoulou and
• Konstantina Yannakopoulou

Beilstein J. Org. Chem. 2014, 10, 2414–2420, doi:10.3762/bjoc.10.251

• δ-position silenced, presented a completely straightforward precursor to 1 and proved to be amenable to coupling with 4 under various reaction conditions. Briefly [14], 8 was prepared from levulinic acid (5) through δ-bromination and concomitant methyl ester formation (compound 6), followed by

• production and CD guest intracellular localization, largely coincided within the cell cytoplasm (Figure 3). This indicates that possibly some of the levulinic acid ester moieties in 2 not have undergone enzymatic cleavage or hydrolysis but instead have proceeded as a conjugate through the heme biosynthesis

Bifunctional dendrons for multiple carbohydrate presentation via carbonyl chemistry

• Davide Bini,
• Francesco Nicotra and
• Laura Cipolla

Beilstein J. Org. Chem. 2014, 10, 1686–1691, doi:10.3762/bjoc.10.177

• carbonyl group at the termini has been carried out. The carbonyl group has been exploited for the multivalent conjugation to a sample saccharide by reductive amination and alkoxyamine conjugation. Keywords: bis-MPA; carbohydrates; dendrons; levulinic acid; multivalency; multivalent glycosystems

• reactions with levulinic acid (15). Building blocks 13 and 14 were synthesized starting from bis-(hydroxymethyl)propionic acid (bis-MPA) and bromo-1-pentene [11] in one and four steps, respectively. L-Fucose derivatives synthesis α-L-(2-Aminoethyl) fucopyranoside (4) and α-O-L-fucopyranosyloxyamine (5) were

• on System Applied Biosystems MDS SCIEX instruments: Q TRAP, LC/MS/MS, turbo ion spray and Q STAR elite nanospray. General procedure for levulinic acid condensation (compounds 1–3): To a 0.1 M solution of the appropriate compound dissolved in dry DCM, levulinic acid (1.2 equiv), DMAP (0.2 equiv) and

Amino acid motifs in natural products: synthesis of O-acylated derivatives of (2S,3S)-3-hydroxyleucine

• Oliver Ries,
• Martin Büschleb,
• Markus Granitzka,
• Dietmar Stalke and
• Christian Ducho

Beilstein J. Org. Chem. 2014, 10, 1135–1142, doi:10.3762/bjoc.10.113

• neither 4 nor 5 gave crystals suitable for X-ray analysis, the 3-hydroxy group of 4 was acylated with levulinic acid, leading to ester 6 in 82% yield (Scheme 1) which crystallized upon removal of residual solvent under reduced pressure. Hence, a single crystal of 6 was obtained, and X-ray crystal

Synthesis of nucleotide–amino acid conjugates designed for photo-CIDNP experiments by a phosphotriester approach

• Tatyana V. Abramova,
• Olga B. Morozova,
• Vladimir N. Silnikov and
• Alexandra V. Yurkovskaya

Beilstein J. Org. Chem. 2013, 9, 2898–2909, doi:10.3762/bjoc.9.326

• ), evaporation of resulting mixture and drying the oil residue by coevaporation with acetonitrile (2 × 25 mL) and Py (2 × 20 mL). Levulinic acid (11.6 g, 100 mmol) and DCC (10.3 g, 50 mmol) was dissolved in diethyl ether (150 mL), and the mixture was stirred for 3 h. After filtration, the diethyl ether was