Peptide stapling by late-stage Suzuki–Miyaura cross-coupling

• Hendrik Gruß,
• Rebecca C. Feiner,
• Ridhiwan Mseya,
• David C. Schröder,
• Michał Jewgiński,
• Kristian M. Müller,
• Rafał Latajka,
• Antoine Marion and
• Norbert Sewald

Beilstein J. Org. Chem. 2022, 18, 1–12, doi:10.3762/bjoc.18.1

• phthaloyl-protected N-terminal alanine was also used for macrocyclisation in peptide stapling [51][52]. Besides addressing the indole C2, the regioselective enzymatic halogenation at C5, C6, or C7 using FAD-dependent tryptophan halogenases opens a broad area of Pd-catalysed late-stage diversifications [53

• partner β-catenin. The N-terminal FITC-labelled RCM-stapled peptide fStAx-3 was synthesised as tracer for this study and its dissociation constant was determined to be 63 ± 6 nM in a direct fluorescence polarisation assay, which is in agreement with previously reported data [77]. Noteworthy, the isomer

First total synthesis of hoshinoamide A

• Haipin Zhou,
• Zihan Rui,
• Yiming Yang,
• Shengtao Xu,
• Yutian Shao and
• Long Liu

Beilstein J. Org. Chem. 2021, 17, 2924–2931, doi:10.3762/bjoc.17.201

• -Val5 and N-Me-ᴅ/ʟ-Phe2. Hoshinoamide C includes two N-methyl amino acids: N-Me-ᴅ-Phe2 and N-Me-ᴅ-IIe5. The C-terminal Pro is functionalized as methyl ester, while the N-terminal polypeptide is linked to the long alkyl chain amino acid Aha8/Ana8/Ama7 and p-hydroxybenzoic acid Hba9/Hba8. Hoshinoamides

Chemical approaches to discover the full potential of peptide nucleic acids in biomedical applications

• Nikita Brodyagin,
• Martins Katkevics,
• Venubabu Kotikam,
• Christopher A. Ryan and
• Eriks Rozners

Beilstein J. Org. Chem. 2021, 17, 1641–1688, doi:10.3762/bjoc.17.116

Antiviral therapy in shrimp through plant virus VLP containing VP28 dsRNA against WSSV

• Santiago Ramos-Carreño,
• Ivone Giffard-Mena,
• Jose N. Zamudio-Ocadiz,
• Alfredo Nuñez-Rivera,
• Ricardo Valencia-Yañez,
• Jaime Ruiz-Garcia,
• Maria Teresa Viana and
• Ruben D. Cadena-Nava

Beilstein J. Org. Chem. 2021, 17, 1360–1373, doi:10.3762/bjoc.17.95

• -dsRNA to form procapsids and CP-RNA complexes [42]. The dsRNA negative charges can be neutralized by the positive N-terminal protein in these procapsids [42]. However, procapsids are not suitable for any treatment because they do not efficiently protect their cargo. The dsRNA in the procapsids may be

Enhanced target cell specificity and uptake of lipid nanoparticles using RNA aptamers and peptides

• Roslyn M. Ray,
• Anders Højgaard Hansen,
• Maria Taskova,
• Bernhard Jandl,
• Jonas Hansen,
• Citra Soemardy,
• Kevin V. Morris and
• Kira Astakhova

Beilstein J. Org. Chem. 2021, 17, 891–907, doi:10.3762/bjoc.17.75

• peptides were included in this study and modified with an N-terminal lipid anchor for LNP postinsertion. The design of the lipid anchor includes two palmitoyl chains that are attached through a 1,2-diaminopropanoic acid moiety (Dap) on the N-terminus of each peptide, providing the lipidated peptides

Synthetic strategies of phosphonodepsipeptides

• Jiaxi Xu

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

• chlorination. After the treatment of compound 39 with piperidine, the N-terminal free dipeptide was obtained and acylated with hexanedioic anhydride to afford the designed hapten 40 (Scheme 7) [11]. Phosphonodepsioctapeptide 41 was prepared as a variation of the partial sequence of a gene product of erb B-2

Biochemistry of fluoroprolines: the prospect of making fluorine a bioelement

• Vladimir Kubyshkin,
• Rebecca Davis and
• Nediljko Budisa

Beilstein J. Org. Chem. 2021, 17, 439–460, doi:10.3762/bjoc.17.40

• starts immediately after the synthesis, inside the ribosome tunnel. The tunnel accommodates between 30 and 40 amino acid residues [93][94]. The trigger factor (gene tig) is a generic chaperone that facilitates the folding of the N-terminal protein section emerging from the ribosome [95]. The proline

• stability effects when incorporated at the positions Pro-4 and Pro-7, despite the fact that both residues are located in the N-terminal PII helix. This result was interpreted by differences in the local polar interactions created by the carbon–fluorine bond within the interior of the foldon domain [106

¹⁹F NMR as a tool in chemical biology

• Diana Gimenez,
• Aoife Phelan,
• Cormac D. Murphy and
• Steven L. Cobb

Beilstein J. Org. Chem. 2021, 17, 293–318, doi:10.3762/bjoc.17.28

• -structural protein 1 (NS1A) homodimer (Figure 9) [64]. Protein NS1A is a highly conserved virulence factor from influenza virus (H3N2) comprised of an N-terminal double-stranded RNA (dsRNA)-binding domain (RBD) and a multifunctional C-terminal effector domain (ED), each of which can independently form

• -like environments. Specifically, the N-terminal region of the peptide, which includes the first 4-tfmF-labelled amino acid, was shown to be involved in the most important membrane-binding interactions and conformational changes observed, allowing the protein to adopt a metastable aggregation-prone

Enzyme-instructed morphological transition of the supramolecular assemblies of branched peptides

• Dongsik Yang,
• Hongjian He and
• Bing Xu

Beilstein J. Org. Chem. 2020, 16, 2709–2718, doi:10.3762/bjoc.16.221

• of the N-terminal of the branch increased the stability of the branched peptides. Moreover, these branched peptides facilitate the delivery of the proteins into cells. This work contributes insights for the development of peptide supramolecular assemblies via enzymatic noncovalent synthesis in

• cellular environment. Keywords: acetylation; branched peptides; enzyme; nanostructures; N-terminal; responsive; self-assembly; Introduction Peptides, being able to self-assemble to exhibit emergent properties and functions [1][2][3][4][5], have received considerable attentions recently. For example

• proteolysis to cleave the branch off 1, the micelles turn into nanofibers. Acetylation of the N-terminal of the branch forms 2, which exhibits an enhanced stability towards the proteolysis. In addition, the cleavage also occurs at other sites in the branch of 2, albeit less frequently, due to the acetylation

NMR Spectroscopy of supramolecular chemistry on protein surfaces

• Peter Bayer,
• Anja Matena and
• Christine Beuck

Beilstein J. Org. Chem. 2020, 16, 2505–2522, doi:10.3762/bjoc.16.203

• using shaped pulses that are specific for the respective side chain nitrogen atom (≈33 ppm for Lys Nζ and ≈85 ppm for Arg Nε). N-terminal glycine residues are also visible in the Lys-specific spectrum because the chemical shifts of the CαH2-NH3+ moiety also match the selected chemical shift range. Not

GlypNirO: An automated workflow for quantitative N- and O-linked glycoproteomic data analysis

• Toan K. Phung,
• Cassandra L. Pegg and
• Benjamin L. Schulz

Beilstein J. Org. Chem. 2020, 16, 2127–2135, doi:10.3762/bjoc.16.180

• cysteines was set as a fixed modification, and dynamic modifications included deamidation of asparagine, monooxidised methionine, and the formation of pyroglutamate at N-terminal glutamic acid and glutamine. All variable modifications were set as “Common 1” allowing each modification to be present once on a

Naphthalene diimide–amino acid conjugates as novel fluorimetric and CD probes for differentiation between ds-DNA and ds-RNA

• Annike Weißenstein,
• Myroslav O. Vysotsky,
• Ivo Piantanida and
• Frank Würthner

Beilstein J. Org. Chem. 2020, 16, 2032–2045, doi:10.3762/bjoc.16.170

• developed several series of fluorophore–amino acid conjugates, thereby making use of the availability of C- and N-terminal amino acid residues for peptide-bond formation. Also, several short multichromophoric peptide constructs were prepared and studied with regard to their interactions with DNA/RNA [11][12

A smart deoxyribozyme-based fluorescent sensor for in vitro detection of androgen receptor mRNA

• Ekaterina A. Bryushkova,
• Erik R. Gandalipov and
• Julia V. Nuzhina

Beilstein J. Org. Chem. 2020, 16, 1135–1141, doi:10.3762/bjoc.16.100

• the N-terminal domain (NTD). In vitro studies demonstrated that the progressive expansion of the length of the CAG repeat in NTD decreased its transactivation function. Exons 2 and 3 code the central DNA-binding domain and exons 4 to 8 code the C-terminal ligand-binding domain [14][15]. There are

Fluorinated phenylalanines: synthesis and pharmaceutical applications

• Laila F. Awad and
• Mohammed Salah Ayoup

Beilstein J. Org. Chem. 2020, 16, 1022–1050, doi:10.3762/bjoc.16.91

• 148 in variable yields with partial racemization. Phthalimido and trifluoroacetyl N-terminal protecting groups (R1 = Phth or TFA) and unprotected C-terminal derivatives (R2 = H) provided the most efficient outcomes (80 and 67% yield, respectively). An N-acetyl group was also suitable as protecting

• group for the reaction providing the desired product with 57% yield. Also, methyl and ethyl esters as C-terminal protecting groups in combination with phthalimino as the N-terminal protecting group, were both successfully explored. However, when the trifluoroacetyl amide was used as a substrate the

Photocontrolled DNA minor groove interactions of imidazole/pyrrole polyamides

• Sabrina Müller,
• Jannik Paulus,
• Jochen Mattay,
• Heiko Ihmels,
• Veronica I. Dodero and
• Norbert Sewald

Beilstein J. Org. Chem. 2020, 16, 60–70, doi:10.3762/bjoc.16.8

• required because this allowed for an alignment between hydrogen-bonding groups in long polyamides and in the minor groove of DNA [41]. The Fmoc-protected heterocyclic amino acids 2 were obtained from N-methylpyrrole and N-methylimidazole, respectively (Scheme 2A). The N-terminal N-methylpyrrole and N

• -methylimidazole units were introduced by employing diamino derivatives 3 (Scheme 2A) [40]. Moreover, it turned out that coupling the subsequent building block to an N-terminal Im building block was problematic because the amino group of the imidazole derivative 2b is a weak nucleophile, and therefore the Fmoc–Py

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

• , acid-mediated deprotection of the Boc group and final coupling to Boc-ᴅ-alanine. Fully protected tripeptides were transformed by base hydrolysis into the free carboxylic acids, followed by activation of the unprotected C-terminus as a SNAc thioester. Subsequent cleavage of the N-terminal Boc protecting

Synthesis of novel sulfide-based cyclic peptidomimetic analogues to solonamides

• José Brango-Vanegas,
• Luan A. Martinho,
• Lucinda J. Bessa,
• Andreanne G. Vasconcelos,
• Alexandra Plácido,
• Alex L. Pereira,
• José R. S. A. Leite and
• Angelo H. L. Machado

Beilstein J. Org. Chem. 2019, 15, 2544–2551, doi:10.3762/bjoc.15.247

• have been synthesized via solid-phase peptide synthesis and SN2’ reaction on a Morita–Baylis–Hillman (MBH) residue introduced at the N-terminal of a tetrapeptide. This last step takes advantage of the electrophilic feature of the MBH residue and represents a new cyclization strategy occurring. The

• repetitive Fmoc-amino acid couplings yielding the linear resin-bound tetrapeptides 5 (Scheme 3) [37][38]. The MBH acids 3 were coupled to the free amine at the N-terminal of 5 to afford the resin-bound linear peptidomimetics 6, which subsequently had the hydroxy group of the MBH residue acylated with acetic

Sugar-derived oxazolone pseudotetrapeptide as γ-turn inducer and anion-selective transporter

• Sachin S. Burade,
• Sushil V. Pawar,
• Tanmoy Saha,
• Navanath Kumbhar,
• Amol S. Kotmale,
• Manzoor Ahmad,
• Pinaki Talukdar and
• Dilip D. Dhavale

Beilstein J. Org. Chem. 2019, 15, 2419–2427, doi:10.3762/bjoc.15.234

• (TSFAA)-derived homologated linear pentapeptide which showed a well defined intramolecular hydrogen-bonding-stabilized helical array [9][10][11]. Our group has reported a trans-vicinal ᴅ-glucofuranoroic-3,4-diacid with a TAA framework and incorporated it into the N-terminal tetrapeptide sequence (H-Phe

Current understanding and biotechnological application of the bacterial diterpene synthase CotB2

• Ronja Driller,
• Daniel Garbe,
• Norbert Mehlmer,
• Monika Fuchs,
• Keren Raz,
• Dan Thomas Major,
• Thomas Brück and
• Bernhard Loll

Beilstein J. Org. Chem. 2019, 15, 2355–2368, doi:10.3762/bjoc.15.228

• of CotB2. [36][37][38]. Overall structure of CotB2wt in the open, inactive conformation The structure of CotB2wt (PDB-ID 4OMG [38] and PDB-ID 5GUC [36]) is complete, except for the 15 N-terminal and 12 C-terminal residues. CotB2 consists of ten core α-helices (A to J) that are connected by short loop

Synthesis and conformational preferences of short analogues of antifreeze glycopeptides (AFGP)

• Małgorzata Urbańczyk,
• Michał Jewgiński,
• Joanna Krzciuk-Gula,
• Jerzy Góra,
• Rafał Latajka and
• Norbert Sewald

Beilstein J. Org. Chem. 2019, 15, 1581–1591, doi:10.3762/bjoc.15.162

• azidochlorination [25]. Glycosylated building blocks, containing ʟ- or ᴅ-Thr were synthesized (Figure 1) over three steps [26]. The glycosylated building blocks were used in SPPS of model tri- and pentapeptides. The N-terminal end of the products was acetylated and the carboxy terminus was in a form of N

• ] 1.11 (d, J = 6.3 Hz, 3H, Hγ Thr2), 1.19 (d, J = 7.0 Hz, 3H, Hβ Ala3), 1.24 (d, J = 7.0 Hz, 1H, Hβ Ala1), 1.85 (s, 3H, Ac N-terminal), 1.89 (s, 3H, CH3Ac Gal), 2.55 (d, J = 4.4 Hz, 3H, Me C-terminal), 3.46 (dd, J = 10.8, 5,7 Hz, 1H, CH2C6(1) Gal), 3.52 (dd, J = 10.7, 6,6 Hz, 1H, CH2C6(2) Gal), 3.61 (dd

• Thr2), 8.00 (d, J = 7.1 Hz, 1H, HN Ala3), 8.18 (d, J = 7.4 Hz, 1H, HN Ala1); 13C NMR (150 MHz, DMSO-d6) δ [ppm] 18.2 (Cβ Ala1), 18.6 (Cβ Ala3), 19.0 (Cγ Thr2), 22.8 (CAc N-terminal), 23.3 (CAc Gal), 25.9 (Me C-terminal), 48.4 (Cα Ala1), 48.5 (Cα Ala3), 49.9 (C2 Gal), 56.4 (Cα Thr2), 61.1 (C6 Gal), 68.8

Phylogenomic analyses and distribution of terpene synthases among Streptomyces

• Lara Martín-Sánchez,
• Kumar Saurabh Singh,
• Mariana Avalos,
• Gilles P. van Wezel,
• Jeroen S. Dickschat and
• Paolina Garbeva

Beilstein J. Org. Chem. 2019, 15, 1181–1193, doi:10.3762/bjoc.15.115

• of type I terpene synthases, including the aspartate-rich motif, the NSE triad, the pyrophosphate sensor and the RY pair [19][20][21]. Both domains have a catalytic activity, the N-terminal domain for the conversion of FPP into the intermediate sesquiterpene alcohol (1(10)E,5E)-germacradien-11-ol (12

• -dependent methyl transferases were found forming a cluster together with the 2-MIB synthase in several Streptomyces species [26][27]. Besides the C-terminal domain typical of class I terpene synthases, these enzymes contain an additional proline-rich N-terminal domain that appears to be disordered in the

Stereo- and regioselective hydroboration of 1-exo-methylene pyranoses: discovery of aryltriazolylmethyl C-galactopyranosides as selective galectin-1 inhibitors

• Alexander Dahlqvist,
• Axel Furevi,
• Niklas Warlin,
• Hakon Leffler and
• Ulf J. Nilsson

Beilstein J. Org. Chem. 2019, 15, 1046–1060, doi:10.3762/bjoc.15.102

• using a highly diastereoselective hydroboration of C1-exo-methylene pyranosides giving inhibitors with fourfold or better selectivity for galectin-1 over galectin-3, -4C (C-terminal CRD), -4N (N-terminal CRD), -7, -8C, -8N, -9C, and -9N and dissociation constants down to 170 µM. Keywords: C-galactoside

• substituents other than fluorine could be prepared, as they were dehalogenated during the final debenzylation. Galectin binding Galectin-1, -3, -4C (C-terminal CRD), -4N (N-terminal CRD), -7, -8C, -8N, -9C, and -9N affinities for (aryltriazolyl)methyl galactopyranosyls 1a–n were determined in a competitive

• sequence of larger glycans [1][2][3]. Some galectins contain one CRD and occur as monomers or dimers, including galectins -1, -2, -7, -10 and -13 in humans. Others contain 2 different CRDs within the same peptide sequence and include galectins -4, -8, -9 and -12. Galectin-3 contains one CRD and a long N

Non-native autoinducer analogs capable of modulating the SdiA quorum sensing receptor in Salmonella enterica serovar Typhimurium

• Matthew J. Styles and
• Helen E. Blackwell

Beilstein J. Org. Chem. 2018, 14, 2651–2664, doi:10.3762/bjoc.14.243

• proteins consist of two domains: a larger N-terminal ligand-binding domain (LBD) connected to a smaller C-terminal DNA-binding domain (DBD). In 2006, the structure of the EHEC SdiA LBD was solved by NMR in the presence and absence of AHL and demonstrated increased folding and structure upon ligand binding

Targeting the Pseudomonas quinolone signal quorum sensing system for the discovery of novel anti-infective pathoblockers

• Christian Schütz and
• Martin Empting

Beilstein J. Org. Chem. 2018, 14, 2627–2645, doi:10.3762/bjoc.14.241

• could prevent activation of the carbonyl group as a CoA-ester. In 2017, Witzgall et al. were able to co-crystallize 6-FABA-AMP within the N-terminal domain of PqsA (Figure 4) [46]. Key interactions involve a water-mediated hydrogen bond between the amino function of the compound and Q162, as in

Comparative cell biological study of in vitro antitumor and antimetastatic activity on melanoma cells of GnRH-III-containing conjugates modified with short-chain fatty acids

• Eszter Lajkó,
• Sarah Spring,
• Rózsa Hegedüs,
• Beáta Biri-Kovács,
• Sven Ingebrandt,
• Gábor Mező and
• László Kőhidai

Beilstein J. Org. Chem. 2018, 14, 2495–2509, doi:10.3762/bjoc.14.226

• 4Lys could negatively affect the fitting of the conjugates to the N-terminal part of the GnRH-R. On the basis of these findings [4Lys(Bu)]-GnRH-III(Dau=Aoa), was chosen for the further studies (e.g., in vivo experiments [22]) to evaluate the suitability of this conjugate for targeted chemotherapy