Position-dependent impact of hexafluoroleucine and trifluoroisoleucine on protease digestion

• Susanne Huhmann,
• Anne-Katrin Stegemann,
• Kristin Folmert,
• Damian Klemczak,
• Johann Moschner,
• Michelle Kube and
• Beate Koksch

Beilstein J. Org. Chem. 2017, 13, 2869–2882, doi:10.3762/bjoc.13.279

• proteolytic degradation in particular. Meng and Kumar reported that the incorporation of 5,5,5,5’,5’,5’-hexafluoroleucine (HfLeu) into the antimicrobial peptides magainin 2 amide and buforin enhanced their resistance towards proteolytic degradation by trypsin [23]. They also introduced HfLeu into the glucagon

• increased steric bulk of the fluorinated amino acid, meaning protection from protease degradation is a result of the steric occlusion of the peptide from the active site [23][28]. In contrast, the Marsh lab found that the introduction of HfLeu into the antimicrobial peptide MSI-78 only renders it more

Binding abilities of polyaminocyclodextrins: polarimetric investigations and biological assays

• Marco Russo,
• Daniele La Corte,
• Annalisa Pisciotta,
• Serena Riela,
• Rosa Alduina and
• Paolo Lo Meo

Beilstein J. Org. Chem. 2017, 13, 2751–2763, doi:10.3762/bjoc.13.271

• modelled as a mixture of independent virtual weak bases. We already have employed these products as capping agents for the preparation of silver nanocomposites [37], which in turn have been tested as catalysts for nitroarene reduction and as antimicrobial agents in synergism with classical antibiotics [40

Reagent-controlled regiodivergent intermolecular cyclization of 2-aminobenzothiazoles with β-ketoesters and β-ketoamides

• Irwan Iskandar Roslan,
• Kian-Hong Ng,
• Gaik-Khuan Chuah and
• Stephan Jaenicke

Beilstein J. Org. Chem. 2017, 13, 2739–2750, doi:10.3762/bjoc.13.270

• antimicrobial [35][36], antitumor [37][38][39], antibacterial [40], and anti-allergic agents [41]. In addition, compounds with this backbone are employed as kinase inhibitors and receptors [42][43][44] and as a tracer for PET imaging of β-amyloid plaques [45][46]. The conventional approach for the construction

• regioselectively form this instead of 3a and 4. This tricyclic backbone can be found in compounds that possess a wide range of medicinal properties including those with antimalarial [74], anticancer [75][76], antiallergic [77][78], antibacterial [79], and antimicrobial properties [80][81]. In addition, they have

Vinylphosphonium and 2-aminovinylphosphonium salts – preparation and applications in organic synthesis

• Anna Kuźnik,
• Roman Mazurkiewicz and
• Beata Fryczkowska

Beilstein J. Org. Chem. 2017, 13, 2710–2738, doi:10.3762/bjoc.13.269

• in E-configuration. The obtained compounds, particularly the derivative containing a carboxylic group in ortho position of the aromatic ring, exhibited antimicrobial activity [37]. 2. Vinylphosphonium salts in organic synthesis 2.1. Vinylphosphonium salts in the intermolecular Wittig reaction

Exploring mechanochemistry to turn organic bio-relevant molecules into metal-organic frameworks: a short review

• Vânia André,
• Sílvia Quaresma,
• João Luís Ferreira da Silva and
• M. Teresa Duarte

Beilstein J. Org. Chem. 2017, 13, 2416–2427, doi:10.3762/bjoc.13.239

• to approximately 80 °C. Both BioMOFs were obtained recurring to manual mechanochemistry. Due to the possibility of synergic effects with Ag+, a known antimicrobial agent, the new network with 4-aminosalicylic acid and silver is highly interesting, as it represents a promising candidate to future

Synthesis, effect of substituents on the regiochemistry and equilibrium studies of tetrazolo[1,5-a]pyrimidine/2-azidopyrimidines

• Elisandra Scapin,
• Paulo R. S. Salbego,
• Caroline R. Bender,
• Alexandre R. Meyer,
• Anderson B. Pagliari,
• Tainára Orlando,
• Geórgia C. Zimmer,
• Clarissa P. Frizzo,
• Helio G. Bonacorso,
• Nilo Zanatta and
• Marcos A. P. Martins

Beilstein J. Org. Chem. 2017, 13, 2396–2407, doi:10.3762/bjoc.13.237

• the pharmaceutical field due to their significant potential to exhibit antitumor, antimicrobial, and antioxidant activities [1][2]. In addition to acting as a stimulant of the central nervous system [3], this class of substances plays an important role in drugs that are used to treat obesity, diabetes

• , our research group demonstrated a highly regioselective synthesis of a series of trifluoromethylated tetrazolo[1,5-a]pyrimidines with potent antimicrobial activity [37]. The reaction between several β-alkoxyvinyl trifluoromethyl ketones [CF3C(O)CH=C(R)OCH3] (in which R = Ph, 4-F–C6H4, 4-Cl–C6H4, 4-Br

Diosgenyl 2-amino-2-deoxy-β-D-galactopyranoside: synthesis, derivatives and antimicrobial activity

• Henryk Myszka,
• Patrycja Sokołowska,
• Agnieszka Cieślińska,
• Andrzej Nowacki,
• Maciej Jaśkiewicz,
• Wojciech Kamysz and
• Beata Liberek

Beilstein J. Org. Chem. 2017, 13, 2310–2315, doi:10.3762/bjoc.13.227

• the obtained compounds are active against Gram-positive bacteria and Candida type fungi. Keywords: antimicrobial activities; D-galactosamine; diosgenin; glycosylation; saponin; tetrachlorophthalimido derivatives; Introduction Saponins are steroid or triterpenoid glycosides found in various plants [1

• antimicrobial activity the N-acyl (6, 7), 2-ureido (8–10), N-monoalkyl (11) and N,N-dialkyl (12, 13) derivatives of diosgenyl 2-amino-2-deoxy-β-D-galactopyranoside were also synthesized (Figure 1). The N-acetyl derivative 6 was obtained by the treatment of 4 with acetic anhydride in methanol with Et3N whereas N

• as well as the HRMS spectrometry confirmed the structures of 11–13 (see Supporting Information File 1 for experimental and NMR data). Evaluation of antimicrobial activity The antimicrobial in vitro activities of 5–13 were tested against two fungal strains: Candida albicans and Candida tropicalis, and

Preparation of imidazo[1,2-a]-N-heterocyclic derivatives with gem-difluorinated side chains

• Layal Hariss,
• Kamal Bou Hadir,
• Mirvat El-Masri,
• Thierry Roisnel,
• René Grée and
• Ali Hachem

Beilstein J. Org. Chem. 2017, 13, 2115–2121, doi:10.3762/bjoc.13.208

• compounds are frequently found in bioactive naturally occurring compounds, as well as in the synthetic pharmacopeia. Imidazo[1,2-a]pyridine is an important heterocyclic system present in many molecules featuring diverse biological activities, such as antiviral, antimicrobial, antitumor, anti-inflammatory

The chemistry and biology of mycolactones

• Matthias Gehringer and
• Karl-Heinz Altmann

Beilstein J. Org. Chem. 2017, 13, 1596–1660, doi:10.3762/bjoc.13.159

• endothelial cells [86], while T cells [87][88] and macrophages [80][89] are less sensitive. Strikingly, no toxic potential was observed against human hepatoma HuH7 or human embryonic kidney HEK293 T cells [85]. Intriguingly, mycolactone A/B lacks antimicrobial activity [90], which suggests that the defense

Syntheses of 3,4- and 1,4-dihydroquinazolines from 2-aminobenzylamine

• Jimena E. Díaz,
• Silvia Ranieri,
• Nadia Gruber and
• Liliana R. Orelli

Beilstein J. Org. Chem. 2017, 13, 1470–1477, doi:10.3762/bjoc.13.145

• analogues, dihydroquinazolines, also represent heterocyclic cores of pharmacological interest. Some derivatives containing this motif have shown antimicrobial [11] and antifungal properties [12]. Their activity as selective T-type calcium channel blockers [13][14][15] and as inhibitors of β-secretase (an

A new member of the fusaricidin family – structure elucidation and synthesis of fusaricidin E

• Marcel Reimann,
• Louis P. Sandjo,
• Luis Antelo,
• Eckhard Thines,
• Isabella Siepe and
• Till Opatz

Beilstein J. Org. Chem. 2017, 13, 1430–1438, doi:10.3762/bjoc.13.140

• family which were isolated from several strains of Paenibacillus polymyxa [3][4]. Fusaricidins exhibit antimicrobial activity against Gram-positive bacteria and a wide range of fungi including Leptosphaeria maculans, a plant pathogenic fungus responsible for the blackleg disease on Brassica crops [5][6

Switchable highly regioselective synthesis of 3,4-dihydroquinoxalin-2(1H)ones from o-phenylenediamines and aroylpyruvates

• Juraj Dobiaš,
• Marek Ondruš,
• Gabriela Addová and
• Andrej Boháč

Beilstein J. Org. Chem. 2017, 13, 1350–1360, doi:10.3762/bjoc.13.132

• could expand the synthetic impact of our results. Keywords: controlled regioselectivity; cyclocondensation; 3,4-dihydroquinoxaline-2(1H)one; HOBt/DIC; mechanism; Introduction The quinoxalin-2(1H)-one moiety is frequently found in compounds that exhibit biological activity, particularly antimicrobial

• have described similar biological activities to the parent quinoxalin-2(1H)-ones 1. Mashevskaya et al. reported about an antimicrobial activity for compound 6 at 1 mg/mL for S. aureus P-209 and E. coli M17 strains [11]. Several recent studies have identified 3,4-dihydroquinoxalin-2(1H)-ones 7–10 as

BODIPY-based fluorescent liposomes with sesquiterpene lactone trilobolide

• Ludmila Škorpilová,
• Silvie Rimpelová,
• Michal Jurášek,
• Miloš Buděšínský,
• Jana Lokajová,
• Roman Effenberg,
• Petr Slepička,
• Tomáš Ruml,
• Eva Kmoníčková,
• Pavel B. Drašar and
• Zdeněk Wimmer

Beilstein J. Org. Chem. 2017, 13, 1316–1324, doi:10.3762/bjoc.13.128

• defence mechanisms. This molecule is produced by macrophages and the antimicrobial and antiparasitic properties of NO have been well described [38]. Currently, the role of NO as a mediator between chronic inflammation and carcinogenesis is intensively studied [39]. The expression of inducible NO is under

Biomimetic molecular design tools that learn, evolve, and adapt

• David A Winkler

Beilstein J. Org. Chem. 2017, 13, 1288–1302, doi:10.3762/bjoc.13.125

• unknown mechanism for osteogenesis that may be exploited to stimulate bone growth in grafts or in patients suffering age-related bone loss. Machine learning and evolutionary design: pathogen-resistant polymers Antimicrobial drugs and materials are becoming extremely important due to the rise in nosocomial

New tricks of well-known aminoazoles in isocyanide-based multicomponent reactions and antibacterial activity of the compounds synthesized

• Maryna V. Murlykina,
• Maryna N. Kornet,
• Sergey M. Desenko,
• Svetlana V. Shishkina,
• Oleg V. Shishkin,
• Aleksander A. Brazhko,
• Vladimir I. Musatov,
• Erik V. Van der Eycken and
• Valentin A. Chebanov

Beilstein J. Org. Chem. 2017, 13, 1050–1063, doi:10.3762/bjoc.13.104

• obtained were evaluated for their antibacterial activity and several of them demonstrated a weak antimicrobial effect, but for most of the compounds a 30–50% increase in biomass of Gram-positive strains (mainly B. subtilis) compared to control was observed. Keywords: 3-amino-5-methylisoxazole; 5-amino-N

• of diseases. However, we are still facing the problem of untreated ones, together with the appearance of unknown disorders and the dramatical growth of antimicrobial resistance caused by the continuous evolution of microorganisms [1][2][3][4][5]. Therefore, there is urgency in careful screening the

• -positive) and Escherichia coli (strain 1257), Pseudomonas aeruginosa (strain 1111) (Gram-negative). As it follows from the results obtained several of the substances studied inhibit the growth of test-microorganisms demonstrating a weak antimicrobial effect (Table 7). Generally, the compounds were found to

Glyco-gold nanoparticles: synthesis and applications

• Federica Compostella,
• Olimpia Pitirollo,
• Alessandro Silvestri and
• Laura Polito

Beilstein J. Org. Chem. 2017, 13, 1008–1021, doi:10.3762/bjoc.13.100

• glucose and galactose moieties multi-displayed on gold surface acted as target for asialoglycoprotein receptors, over-expressed on liver cancer cells, delivering selectively the anticancer drug Au(I). In search of novel antimicrobial antigens, chitosan-streptomycin GAuNPs (CA NPs), i.e., carbohydrate

Metal-free hydroarylation of the side chain carbon–carbon double bond of 5-(2-arylethenyl)-3-aryl-1,2,4-oxadiazoles in triflic acid

• Anna S. Zalivatskaya,
• Dmitry S. Ryabukhin,
• Marina V. Tarasenko,
• Alexander Yu. Ivanov,
• Irina A. Boyarskaya,
• Elena V. Grinenko,
• Ludmila V. Osetrova,
• Eugeniy R. Kofanov and
• Aleksander V. Vasilyev

Beilstein J. Org. Chem. 2017, 13, 883–894, doi:10.3762/bjoc.13.89

• , such as analgesic [9], anti-inflammatory [10], antimicrobial [11], antidiabetic [12], and anticancer [13] to name a few. Some representatives of 1,2,4-oxadiazole-based drugs are shown in Figure 1. Libexin and oxolamine are used as antitussive (cough) agents [14], butalamine is a coronary vasodilator

Opportunities and challenges for the sustainable production of structurally complex diterpenoids in recombinant microbial systems

• Katarina Kemper,
• Max Hirte,
• Markus Reinbold,
• Monika Fuchs and
• Thomas Brück

Beilstein J. Org. Chem. 2017, 13, 845–854, doi:10.3762/bjoc.13.85

• stereoselective synthesis of (1R,3E,7E,11S,12S)-3,7,18-dolabellatriene, a bicyclic diterpene (Scheme 2). Dollabellanes derive mostly from marine organisms and display bioactivities such as antiviral and cytotoxic effects [59]. Dolabellatriene from a reprogrammed CotB2 contribute with antimicrobial activity

• antimicrobial or anti-allergic potential. Acknowledgements KK, MH, MF and TB gratefully acknowledge the support of SysBioTerp project funded by the Federal Ministry of Education and Research in the Systems Biology funding framework (BMBF; Grant number: 031A305A). MR and TB thankfully acknowledge the support of

The effect of cyclodextrin complexation on the solubility and photostability of nerolidol as pure compound and as main constituent of cabreuva essential oil

• Joyce Azzi,
• Pierre-Edouard Danjou,
• David Landy,
• Steven Ruellan,
• Lizette Auezova,
• Hélène Greige-Gerges and
• Sophie Fourmentin

Beilstein J. Org. Chem. 2017, 13, 835–844, doi:10.3762/bjoc.13.84

• cabreuva essential oil (EO) (Myrocarpus fastigiatus) [3]. Due to its antimicrobial effects against a wide range of microorganisms such as Staphylococcus aureus, Salmonella enterica and Aspergillus niger [4], Ner can be employed as natural alternative to traditional synthetic food preservatives. To achieve

Nucleophilic and electrophilic cyclization of N-alkyne-substituted pyrrole derivatives: Synthesis of pyrrolopyrazinone, pyrrolotriazinone, and pyrrolooxazinone moieties

• Işıl Yenice,
• Sinan Basceken and
• Metin Balci

Beilstein J. Org. Chem. 2017, 13, 825–834, doi:10.3762/bjoc.13.83

• (Figure 1) [7][8]. Triazinone heterocycles are essential in organic synthesis regarding their herbicide, anticancer, antimicrobial, and antimetastatic activities. Metamitron (3) and metribuzin (4), 1,2,4-triazinone herbicides having an amino group, are absorbed by the roots of plants and inhibit

N-Propargylamines: versatile building blocks in the construction of thiazole cores

• S. Arshadi,
• E. Vessally,
• L. Edjlali,
• R. Hosseinzadeh-Khanmiri and
• E. Ghorbani-Kalhor

Beilstein J. Org. Chem. 2017, 13, 625–638, doi:10.3762/bjoc.13.61

• ], antimicrobial [57][58][59], and specially antibiotic [60][61][62][63][64] agents. Despite their great relevance in drug design, only very few synthetic methods towards these compounds have been reported to date [44]. N-Propargylamines are one of the most specific class of alkynes having diverse reaction

Synthesis of 1-indanones with a broad range of biological activity

• Marika Turek,
• Dorota Szczęsna,
• Marek Koprowski and
• Piotr Bałczewski

Beilstein J. Org. Chem. 2017, 13, 451–494, doi:10.3762/bjoc.13.48

• allowed the synthesis of 60 in yields ranged from 31 to 56%. 1-Indanones exhibit a broad spectrum of biological activity including anti-inflammatory [41], analgesic [42], antimicrobial [43], antiviral [5], anticancer [44] and antimalarial [45] activity. A combination of two or more biologically active

• moieties may increase or decrease the biological activity. A series of isoxazole fused 1-indanones 64 with increased anti-inflammatory and antimicrobial activity has been synthesized by Giles et al. [46]. In this synthesis, diethyl phthalate (61) was reacted with ethyl acetate to obtain indane-1,3-dione

Biosynthetic origin of butyrolactol A, an antifungal polyketide produced by a marine-derived Streptomyces

• Enjuro Harunari,
• Hisayuki Komaki and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2017, 13, 441–450, doi:10.3762/bjoc.13.47

• recently, isolation of butyrolactols C and D was presented but the details are not available in public domains [10]. 1 has a broad antimicrobial activity against fungi ranging from Candida albicans to Trichophyton mentagrophytes with comparative activity to nystatin [9]. Despite the uniqueness of the

Synthesis and evaluation of anti-oxidant and cytotoxic activities of novel 10-undecenoic acid methyl ester based lipoconjugates of phenolic acids

• Naganna Narra,
• Shiva Shanker Kaki,
• Rachapudi Badari Narayana Prasad,
• Sunil Misra,
• Koude Dhevendar,
• Venkateshwarlu Kontham and
• Padmaja V. Korlipara

Beilstein J. Org. Chem. 2017, 13, 26–32, doi:10.3762/bjoc.13.4

• are a class of natural compounds which are found ubiquitously in the plant kingdom. They are reported to possess a wide range of biological properties like anti-oxidant, antimicrobial, anti-inflammatory, anticarcinogenic and antiviral activities [1]. The phenolic acids are also reported to show in

• transesterified with different oils or triglycerides [6]. Apart from these structured phenolipids, different fatty acids were esterified with phenolic compounds to produce novel esters which were evaluated for anti-oxidant and antimicrobial activities [7][8]. However, there are very few reports where the phenolic

First DMAP-mediated direct conversion of Morita–Baylis–Hillman alcohols into γ-ketoallylphosphonates: Synthesis of γ-aminoallylphosphonates

• Marwa Ayadi,
• Haitham Elleuch,
• Emmanuel Vrancken and
• Farhat Rezgui

Beilstein J. Org. Chem. 2016, 12, 2906–2915, doi:10.3762/bjoc.12.290

• interesting antimicrobial and antimalarial properties [8][9], as well as useful substrates for the synthesis of valuable organic compounds [10][11][12]. Historically, the Michaelis−Arbuzov rearrangement [13] is the most widely and generally high yielding strategy for phosphonate synthesis. The current three