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Search for "amino groups" in Full Text gives 166 result(s) in Beilstein Journal of Organic Chemistry.

Aromatic and heterocyclic perfluoroalkyl sulfides. Methods of preparation

  • Vladimir N. Boiko

Beilstein J. Org. Chem. 2010, 6, 880–921, doi:10.3762/bjoc.6.88

Graphical Abstract
  • anilines but also for N-monosubstituted substrates and even those with a free NH2 group (Scheme 11). In naphthalene and benzophenone derivatives only those rings containing hydroxy or amino groups undergo perfluoroalkylsulfanylation [74][75]. Other electron-donating substituents on the aromatic ring are
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Review
Published 18 Aug 2010

Synthesis, spectral characterization, electron microscopic study and thermogravimetric analysis of a phosphorus containing dendrimer with diphenylsilanediol as core unit

  • E. Dadapeer,
  • B. Hari Babu,
  • C. Suresh Reddy and
  • Naga Raju Charmarthi

Beilstein J. Org. Chem. 2010, 6, 726–731, doi:10.3762/bjoc.6.85

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  • the general methods used for the synthesis and the growth of the dendrimers. Accordingly, we turned our attention toward the use of –NH2, –CHO and –OH end groups on the surface of dendrimers. Amino groups react easily with aldehydes to form Schiff’s bases. Similarly, the phenolic –OH groups react
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Published 11 Aug 2010
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  • monoester as a reagent in the formation of phosphoethanolamines [29]. Since the amino group in the spacer was already Cbz-protected and we wanted to be able to differentiate between the two amino groups during conjugation, a Boc-protected H-phosphonate monoester 21 was synthesised and used in the
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Published 26 Jul 2010

Chromo- and fluorophoric water-soluble polymers and silica particles by nucleophilic substitution reaction of poly(vinyl amine)

  • Katja Hofmann,
  • Ingolf Kahle,
  • Frank Simon and
  • Stefan Spange

Beilstein J. Org. Chem. 2010, 6, No. 79, doi:10.3762/bjoc.6.79

Graphical Abstract
  • hydrolyzed PVFA contains ca. 5% of formamido groups and 95% of primary amino groups. The water-soluble PVAm copolymer has been widely applied for a number of purposes, e.g., in catalysis [7], chelation [8], treatment of waste water [9], paper making [10], recovery of oil [11] and as superabsorber [12
  • ]. Modified PVAm is expected to be useful in the preparation of polymeric water-soluble dyes [13], in mimicking natural enzymes [14] and as a polymeric surfactant [15]. Depending on the pH of the aqueous solution, the primary amino groups of PVAm can be partly protonated (−NH3+) or they can be present as
  • charge-neutral amines (−NH2). In this context, PVAm can be considered as a weak cationic polyelectrolyte. The pH-variation is an excellent tool to control and adjust the net-charge density along the polymer chain or in a layer made from PVAm [16][17]. Full conversion of the amino groups into their
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Published 22 Jul 2010

Synthesis of glycosylated β3-homo-threonine conjugates for mucin-like glycopeptide antigen analogues

  • Florian Karch and
  • Anja Hoffmann-Röder

Beilstein J. Org. Chem. 2010, 6, No. 47, doi:10.3762/bjoc.6.47

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  • ), HOBt (1 mmol) and DIPEA (2 mmol) in DMF (20–30 min vortex). After every coupling step, unreacted amino groups were capped by treatment with a mixture of Ac2O (0.5 M), DIPEA (0.125 M) and HOBt (0.015 M) in NMP (10 min vortex). Coupling of the glycosylated β3hThr building block 2a (102.70 mg, 0.15 mmol
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Published 12 May 2010

Chemical aminoacylation of tRNAs with fluorinated amino acids for in vitro protein mutagenesis

  • Shijie Ye,
  • Allison Ann Berger,
  • Dominique Petzold,
  • Oliver Reimann,
  • Benjamin Matt and
  • Beate Koksch

Beilstein J. Org. Chem. 2010, 6, No. 40, doi:10.3762/bjoc.6.40

Graphical Abstract
  • ][25][26][27]. We chose a combination of chemical and enzymatic aminoacylation which relies on the hybrid dinucleotide pdCpA and the T4-RNA ligase-mediated coupling to it to give a truncated suppressor tRNA. The Nα-amino groups of the amino acids were protected with the 4-pentenoyl group and the amino
  • , Lane 5: DfeGly-tRNACUA, Lane 6: TfeGly-tRNACUA, Lane 7: α-(Tfm)Ala-tRNACUA. Amino groups are N-(4-pentenoyl) protected. Visualized by using Stains-all (Sigma-Aldrich®). General scheme for the synthesis of an N-(4-pentenoyl) amino acid cyanomethyl ester. General scheme of synthesis of mono-2′(3′)-O-[N
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Preliminary Communication
Published 20 Apr 2010

Molecular recognition of organic ammonium ions in solution using synthetic receptors

  • Andreas Späth and
  • Burkhard König

Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32

Graphical Abstract
  • ammonium ions, such as acetylcholine (3). Amino acids have amino groups like peptides and proteins. Under physiological conditions the amino group is usually protonated as an ammonium ion. The interaction of small ammonium ion bearing compounds with protein receptors is important for biological signal
  • response. Unprotected dipeptides showed an affinity to compound 44 if amino groups were present within a suitable distance, for example, as found in dipeptides with a C-terminal Lys. Lys-Lys (Kass = 1020 M−1) and Gly-Lys (Kass = 930 M−1) showed the highest affinity constants in methanol/water 10:1 [184
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Published 06 Apr 2010

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

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  • between H1, H2, H3 and H4 protons. We assume that the stereochemical course of the hydroxylation of 27 proceeds through syn addition as previously observed in the hydroxylation of 13, a quite similar structure to 27. The all cis-configuration of the acetate and amino groups attached to the six-membered
  • assignment of the exact orientation of the hydroxyl groups. X-ray analysis of 18 (Figure 1) revealed the exact configuration of the compound. This also confirms the configurations of endoperoxide 10, oxazolidinone 13 and cis-hydroxylation product 17. The all cis-configuration of the four acetate and amino
  • groups in aminocyclitol 18 [25] attached to the six-membered ring resembles the configuration of conduramine D-2 [36][37][38]. Hydrolysis of the acetate groups with H2SO4 proceeded smoothly to deliver aminocyclitol 6 in 84% yield. For the synthesis of dichloro derivative, we replaced the acetoxy groups
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Published 15 Feb 2010

Synthesis and binding studies of two new macrocyclic receptors for the stereoselective recognition of dipeptides

  • Ana Maria Castilla,
  • M. Morgan Conn and
  • Pablo Ballester

Beilstein J. Org. Chem. 2010, 6, No. 5, doi:10.3762/bjoc.6.5

Graphical Abstract
  • carboxylic acid functions while the other will participate with its two amino groups. To achieve the regioselective control demanded in the macrocyclization reactions, a precise selection of the orthogonal protecting groups to be included in the bis-amino acid functionalities of the benzophenone derivatives
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Published 19 Jan 2010

The first preparative solution phase synthesis of melanotan II

  • Vladimir V. Ryakhovsky,
  • Georgy A. Khachiyan,
  • Nina F. Kosovova,
  • Elena F. Isamiddinova and
  • Andrey S. Ivanov

Beilstein J. Org. Chem. 2008, 4, No. 39, doi:10.3762/bjoc.4.39

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  • and Discussion To date, several accounts of solid phase synthesis of peptide 2 have been reported. A representative one, reported by Hruby and co-workers, exploited p-methylbenzhydrylamine resin (pMBHA) as the solid support and tert-butyloxycarbonyl (Boc) tactics for temporary protection of α-amino
  • groups. The ε-amino group of lysine and the γ-carboxy group of aspartic acid, involved in lactamization, were protected as the base-cleavable Fmoc amide and Fm ester respectively. After synthesizing the peptide chain and cleavage of the base-labile protecting groups, an efficient on-resin cyclization was
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Published 30 Oct 2008

Perhalogenated pyrimidine scaffolds. Reactions of 5-chloro- 2,4,6-trifluoropyrimidine with nitrogen centred nucleophiles

  • Emma L. Parks,
  • Graham Sandford,
  • John A. Christopher and
  • David D. Miller

Beilstein J. Org. Chem. 2008, 4, No. 22, doi:10.3762/bjoc.4.22

Graphical Abstract
  • may be transformed into a widely diverse range of functionalised derivatives by a sequence of efficient and regioselective reactions, are becoming increasingly important [6][7]. In particular, the attachment of amino groups to the pyrimidine nucleus by formation of carbon-nitrogen bonds is a highly
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Published 01 Jul 2008

Electronic differentiation competes with transition state sensitivity in palladium- catalyzed allylic substitutions

  • Dominik A. Lange and
  • Bernd Goldfuss

Beilstein J. Org. Chem. 2007, 3, No. 36, doi:10.1186/1860-5397-3-36

Graphical Abstract
  • kcal mol-1, Table 1). The highest activation energies result from electron donating amino groups X, Y = NHMe (Figure 3 and Figure 4, Eatrans = 10.67, Eacis = 10.47 kcal mol-1, Table 1, Scheme 2). Such electronic tunings of the ligands strongly affect the reactivity and give rise to increased or
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Published 26 Oct 2007

A hydrogen- bonded channel structure formed by a complex of uracil and melamine

  • Reji Thomas and
  • G. U. Kulkarni

Beilstein J. Org. Chem. 2007, 3, No. 17, doi:10.1186/1860-5397-3-17

Graphical Abstract
  •  1b (see Table 2). It is clear that the amino groups of the melamine molecule act as hydrogen bond donors and ring nitrogens as acceptors. Unlike with adenine, uracil forms two N-H...O bonds (H9....O2, 2.08Å; H7...O1, 2.03Å) on either side of the N-H...N bond (H2...N6, 1.98Å). All the three hydrogen
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Preliminary Communication
Published 23 May 2007

Crystal engineering of analogous and homologous organic compounds: hydrogen bonding patterns in trimethoprim hydrogen phthalate and trimethoprim hydrogen adipate

  • Packianathan Thomas Muthiah,
  • Savarimuthu Francis,
  • Urszula Rychlewska and
  • Beata Warżajtis

Beilstein J. Org. Chem. 2006, 2, No. 8, doi:10.1186/1860-5397-2-8

Graphical Abstract
  • bridges the 2-amino and 4-amino groups on either side of the paired TMP cations, forming 8-membered hydrogen-bonded ring (motif III), with graph-set notation [R22(8)] [27]. The atom O5 of the carboxyl group of the hydrogen phthalate ion forms an intramolecular O-H...O hydrogen bond with the O6 atom of the
  • motif VI, the hydrogen atoms of 2- and 4-amino groups of the TMP cation are hydrogen-bonded to the carboxylate and carboxyl ends, respectively, of the same hydrogen adipate ion. Thus, the hydrogen adipate bridges the 2-amino and 4-amino groups of TMP. These hydrogen-bonded interactions are almost
  • the acid adopts the gtt form [34][35]. The adoption of the bent carbon chain conformation by adipic acid seems necessary in order to place the two terminal carboxyl functions in mutual syn orientation so that they can fasten the 2- and 4-amino groups of the TMP molecule. The disorder, on the other
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Published 07 Apr 2006

Molecular recognition. 1. Crystal structures of hexaazamacrocyclic amines containing p-xylylene spacers and their adducts with acids

  • Teresa Borowiak,
  • Grzegorz Dutkiewicz,
  • Maciej Kubicki,
  • Marek Pietraszkiewicz,
  • Agnieszka Gil and
  • Rainer Mattes

Beilstein J. Org. Chem. 2005, 1, No. 16, doi:10.1186/1860-5397-1-16

Graphical Abstract
  • secondary amine with a lesser effect produced by the spacer. As the number of methylene units increases, the basicity of the macrocyclic ligands also increases because the amino-groups lie further apart from one another [2] in comparison with 1,4,7,16,19,22-hexaaza [9.9]-p-cyclophane (hereafter 2, Scheme 1
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Published 09 Dec 2005

Synthesis and glycosidase inhibitory activity of new hexa- substituted C8-glycomimetics

  • Olivia Andriuzzi,
  • Christine Gravier-Pelletier,
  • Gildas Bertho,
  • Thierry Prangé and
  • Yves Le Merrer

Beilstein J. Org. Chem. 2005, 1, No. 12, doi:10.1186/1860-5397-1-12

Graphical Abstract
  • the spatial disposition of the hydroxy and amino groups which depart too much from that realized in glycomimetics such as valiolamine, voglibose and valienamine. Nevertheless, the synthetic strategy described here is efficient and general, and could be extended to increase the diversity of the
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Published 07 Oct 2005
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