Versatile synthesis of the signaling peptide glorin

• Robert Barnett,
• Daniel Raszkowski,
• Thomas Winckler and
• Pierre Stallforth

Beilstein J. Org. Chem. 2017, 13, 247–250, doi:10.3762/bjoc.13.27

• activate glorin-induced genes in the social amoeba Polysphondylium pallidum was evaluated by quantitative reverse transcription PCR, whereby both compounds showed bioactivity comparable to a glorin standard. This synthetic route will be useful in conducting detailed structure–activity relationship studies

• glorinamide 2: a compound with comparable bioactivity, that is hydrolytically – and thus metabolically – more stable than glorin (1) [14]. The molecules were shown to be bioactive, effectively mediating the induction of gene expression during early development, as determined by quantitative reverse

An effective one-pot access to polynuclear dispiroheterocyclic structures comprising pyrrolidinyloxindole and imidazothiazolotriazine moieties via a 1,3-dipolar cycloaddition strategy

• Alexei N. Izmest’ev,
• Galina A. Gazieva,
• Natalya V. Sigay,
• Sergei A. Serkov,
• Valentina A. Karnoukhova,
• Vadim V. Kachala,
• Alexander S. Shashkov,
• Igor E. Zanin,
• Angelina N. Kravchenko and
• Nina N. Makhova

Beilstein J. Org. Chem. 2016, 12, 2240–2249, doi:10.3762/bjoc.12.216

• compounds having the spiropyrrolidinyloxindole core [14][15][16][17][18]. The 3,3’-spiropyrrolidinyloxindole unit is found in the molecular skeleton of a large family of natural alkaloids with remarkable bioactivity profiles and interesting structural properties [19][20]. Derivatives with the 2,3

A new and expeditious synthesis of all enantiomerically pure stereoisomers of rosaprostol, an antiulcer drug

• Wiesława Perlikowska,
• Remigiusz Żurawiński and
• Marian Mikołajczyk

Beilstein J. Org. Chem. 2016, 12, 2234–2239, doi:10.3762/bjoc.12.215

• stereostructure–bioactivity relationship in biologically active compounds [18][19], including selected prostanoids [20][21][22], we decided to synthesize all four rosaprostol stereoisomers 1a–d in enantiomerically pure form (Figure 2). The two rosaprostol stereoisomers 1c and 1d have an absolute configuration at

Tunable microwave-assisted method for the solvent-free and catalyst-free peracetylation of natural products

• Manuela Oliverio,
• Paola Costanzo,
• Monica Nardi,
• Carla Calandruccio,
• Raffaele Salerno and
• Antonio Procopio

Beilstein J. Org. Chem. 2016, 12, 2222–2233, doi:10.3762/bjoc.12.214

• , phenols and amino groups is a classical protection method in multistep syntheses as well as a transient chemical modification to improve the bioavailaibility and bioactivity of hydrophilic drugs and natural polyols [1][2][3][4][5][6][7][8][9]. Several in vitro and in vivo studies on peracetylated

TMSBr-mediated solvent- and work-up-free synthesis of α-2-deoxyglycosides from glycals

• Mei-Yuan Hsu,
• Yi-Pei Liu,
• Sarah Lam,
• Su-Ching Lin and
• Cheng-Chung Wang

Beilstein J. Org. Chem. 2016, 12, 1758–1764, doi:10.3762/bjoc.12.164

• ); Introduction Deoxyglycosides are essential moieties of numerous bioactive natural products, and are prevalent subunits in antitumor and antibiotic agents [1][2][3]. Furthermore, 2-deoxy- and 2,6-dideoxyglycosides are crucial components for the pharmacology and bioactivity of many biologically active compounds

Organic chemistry meets polymers, nanoscience, therapeutics and diagnostics

• Vincent M. Rotello

Beilstein J. Org. Chem. 2016, 12, 1638–1646, doi:10.3762/bjoc.12.161

• was "not very well". Binding of the nanoparticle induced protein denaturation, with loss of bioactivity [42]. We hypothesized that this denaturation arose from interaction of the protein with the hydrophobic elements of the simple ligands we were using. This hypothesis led us to create what we call

Total synthesis of leopolic acid A, a natural 2,3-pyrrolidinedione with antimicrobial activity

• Atul A. Dhavan,
• Rahul D. Kaduskar,
• Loana Musso,
• Leonardo Scaglioni,
• Piera Anna Martino and
• Sabrina Dallavalle

Beilstein J. Org. Chem. 2016, 12, 1624–1628, doi:10.3762/bjoc.12.159

• -pyrrrolidinedione nucleus are indeed very few [4][5][6]. Even though this core can be considered an attractive target, synthetic studies directed to find new biologically active compounds are scarce as well [7][8][9]. The unique structure and bioactivity of leopolic acid prompted us to plan a synthesis which might

Microwave-assisted synthesis of (aminomethylene)bisphosphine oxides and (aminomethylene)bisphosphonates by a three-component condensation

• Erika Bálint,
• Ádám Tajti,
• Anna Dzielak,
• Gerhard Hägele and
• György Keglevich

Beilstein J. Org. Chem. 2016, 12, 1493–1502, doi:10.3762/bjoc.12.146

• treatment of osteoporosis and related bone diseases [1][2][3]. In the last decades, at least three generations of dronic acid derivatives appeared [4]. (Aminomethylene)bisphosphonic acid derivatives are analogous species, that also have potential bioactivity in bone diseases, besides they display

Cyclisation mechanisms in the biosynthesis of ribosomally synthesised and post-translationally modified peptides

• Andrew W. Truman

Beilstein J. Org. Chem. 2016, 12, 1250–1268, doi:10.3762/bjoc.12.120

• species represents another partially characterised pathway that features an unusual cyclised RiPP [133]. Mature ComX is a secreted RiPP that functions as a signal in this QS system, and the cyclised residue is crucial for its bioactivity [134]. The precursor peptide ComX is modified by a isoprenyl

Marine-derived myxobacteria of the suborder Nannocystineae: An underexplored source of structurally intriguing and biologically active metabolites

• Antonio Dávila-Céspedes,
• Peter Hufendiek,
• Max Crüsemann,
• Till F. Schäberle and
• Gabriele M. König

Beilstein J. Org. Chem. 2016, 12, 969–984, doi:10.3762/bjoc.12.96

• designed to tackle the sometimes cumbersome task of finding bioactive secondary metabolites of bacterial origin, i.e., mainly bioactivity- or chemistry-guided methods. An additional approach, complementary to the latter, arose in the late 1990s, when the first microbial genomes were sequenced, allowing

• an MIC value of 16 μg mL−1. Further bioactivity assays were impossible to carry out due to the minute amounts in which this metabolite is produced. Consequently, a synthetic approach has been utilized in order to overcome this problem, leading so far to the synthesis of the tricyclic core structure

Is conformation a fundamental descriptor in QSAR? A case for halogenated anesthetics

• Maria C. Guimarães,
• Mariene H. Duarte,
• Josué M. Silla and
• Matheus P. Freitas

Beilstein J. Org. Chem. 2016, 12, 760–768, doi:10.3762/bjoc.12.76

• descriptors (MD) for correlation with bioactivity values. This is not a simple task because the bioactive conformation in molecule data sets is usually unknown and, therefore, optimized structures in a receptor-free environment are often used to generate the MD´s. In this case, a wrong conformational choice

• useful for understanding the action mechanism of related drugs, as well as to drive the synthesis of new drug like compounds. Since the milestone work by Hansch and Fujita [1], a variety of MD´s have been developed to improve the correlation of chemical structures with bioactivity, ranging from

• ], but these are mostly complementary and are aimed at corroborating and/or rationalizing the results provided by the regression models, since the docking methodology itself provides intermolecular energies and docking scores that correlate with bioactivity. On the other hand, despite not encoding

Three new trixane glycosides obtained from the leaves of Jungia sellowii Less. using centrifugal partition chromatography

• Luíse Azevedo,
• Larissa Faqueti,
• Marina Kritsanida,
• Antonia Efstathiou,
• Despina Smirlis,
• Gilberto C. Franchi Jr,
• Grégory Genta-Jouve,
• Sylvie Michel,
• Louis P. Sandjo,
• Raphaël Grougnet and
• Maique W. Biavatti

Beilstein J. Org. Chem. 2016, 12, 674–683, doi:10.3762/bjoc.12.68

• see Table 2 and Table 3. Bioactivity tests Evaluation of antileishmanial activity L. donovani (strain LG13, MHOM/ET/0000/HUSSEN), L. infantum (MHOM/GR/2002/GH12) and L. amazonensis (MPRO/BR/72/M1845) promastigotes and the murine macrophage J774 cell line (American Type Culture Collection, Manassas, VA

Antibiotics from predatory bacteria

• Juliane Korp,
• María S. Vela Gurovic and
• Markus Nett

Beilstein J. Org. Chem. 2016, 12, 594–607, doi:10.3762/bjoc.12.58

• complement the bioactivity of myxovirescins and, thereby, expand the prey spectrum. Alternatively, it is possible that the killing of M. luteus involves a different predation strategy (e.g., attack with hydrolytic enzymes). In any case, the coordinate production of antibiotics, such as myxovirescin A

• -positive bacteria. Bioactivity-guided fractionation then led to the identification of the gulmirecins as the active principles [87]. Chemically, the gulmirecins form a novel class of antibiotics together with the disciformycins [92], which were discovered in a different P. fallax strain upon a large-scale

• bioactivity data of the disciformycins suggests that the isovalerate motive is important for the antibacterial activity. Due to their potent effects against human pathogenic staphylococci as well as negligible toxicity, gulmirecins A and disciformycin B have become promising candidate compounds for the design

Biosynthesis of α-pyrones

• Till F. Schäberle

Beilstein J. Org. Chem. 2016, 12, 571–588, doi:10.3762/bjoc.12.56

• involved in inflammation reactions. The authors isolated 23, 24 and 27 from the feces of Trogopterus xanthipes (flying squirrel) by bioactivity-guided fractionation, and determined IC50 values for the pure compounds to be in the low mM range (1.33, 1.07 and 2.33 mM, respectively) [31]. Also estrogenic and

Physical properties and biological activities of hesperetin and naringenin in complex with methylated β-cyclodextrin

• Waratchada Sangpheak,
• Jintawee Kicuntod,
• Roswitha Schuster,
• Thanyada Rungrotmongkol,
• Peter Wolschann,
• Nawee Kungwan,
• Helmut Viernstein,
• Monika Mueller and
• Piamsook Pongsawasdi

Beilstein J. Org. Chem. 2015, 11, 2763–2773, doi:10.3762/bjoc.11.297

• three different cancer cell lines. The overall results suggested that solubilities and bioactivities of both flavanones were increased by complexation with methylated β-CDs. Keywords: binding energy; bioactivity; cyclodextrins; hesperetin; naringenin; Introduction Flavonoids are secondary metabolites

Recent highlights in biosynthesis research using stable isotopes

• Jan Rinkel and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2015, 11, 2493–2508, doi:10.3762/bjoc.11.271

• compound. In conclusion, these feeding experiments using isotopically labeled precursors supported the biosynthetic assembly from an unusual PKS starter unit which results in the remarkable scaffold for the bioactivity-generating functionalities. A similar study showing the enduring significance of labeled

• -ribosomal peptides Non-ribosomal peptides often exhibit a high bioactivity and are biosynthesized by non-ribosomal peptide synthethases (NRPS) [33], which work RNA-independent and catalyze the assembly of both proteinogenic and non-proteinogenic amino acids in a modular fashion. Moreover, NRPSs can contain

• products and are remarkably diverse in structure, bioactivity, and use. Prominent examples such as the antimalaria drug artemisinin (28) from Artemisia annua, ingenol (29) and its derivatives from Euphorbia ingens [56], or the anticancer drug paclitaxel (30) feature highly functionalized polycyclic carbon

Molecular-oxygen-promoted Cu-catalyzed oxidative direct amidation of nonactivated carboxylic acids with azoles

• Wen Ding,
• Shaoyu Mai and
• Qiuling Song

Beilstein J. Org. Chem. 2015, 11, 2158–2165, doi:10.3762/bjoc.11.233

• key intermediate to make the subsequent amide formation feasible (Scheme 1b). In our work, azoles have been chosen as the amines due to their special bioactivity [31]. To the best of our knowledge, Cu salt has not yet been used for catalyzed, oxidative direct amide formation. We report the first

SmI₂-mediated dimerization of indolylbutenones and synthesis of the myxobacterial natural product indiacen B

• Nils Marsch,
• Peter G. Jones and
• Thomas Lindel

Beilstein J. Org. Chem. 2015, 11, 1700–1706, doi:10.3762/bjoc.11.184

• analysis of indiacen B (2, ORTEP drawing with ellipsoides at 50% probability). Supporting Information Supporting Information File 244: Experimental procedures, bioactivity tables, X-ray figures and tables, HPLC chromatograms and NMR spectra for all compounds, NOESY analyses. Acknowledgements We thank

Pyridinoacridine alkaloids of marine origin: NMR and MS spectral data, synthesis, biosynthesis and biological activity

• Louis P. Sandjo,
• Victor Kuete and
• Maique W. Biavatti

Beilstein J. Org. Chem. 2015, 11, 1667–1699, doi:10.3762/bjoc.11.183

• are also discussed. Pyridoacridines were found to have a large spectrum of bioactivity and this review highlights and compares the pharmacophores that are responsible for the observed bioactivity. Keywords: biosynthesis; 13C NMR shifts; pharmacophores; pyridoacridines; synthesis; Introduction In

• , terpenoids, phenolics, polysaccharides and alkaloids [4]. Various bioactivity functions such as anticancer [5][6][7], phytotoxicity [8][9][10][11], antioxidant [12][13][14][15][16], antimicrobial [17][18][19], analgesic [20][21], hypotensive [22], hypoglycemic [23], antiprotozoal [24] and plant protecting

• ] that summarize their bioactivity. Herein, a synopsis of the newly published bioactivity of pyridoacridine will be provided as well as pharmacophores associated with the activity and a discussion on the evolution of the bioactivity and the structure modification. Cytotoxicity The biologically tested

Selected synthetic strategies to cyclophanes

• Sambasivarao Kotha,
• Mukesh E. Shirbhate and
• Gopalkrushna T. Waghule

Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142

• and nanomaterials is a challenging task. Huang and co-workers [165] have reported a taco complex template method to synthesize a cryptand/paraquat [2]rotaxane and [2]catenane (e.g., 207) by using RCM as a key step. Structural features and interesting bioactivity of the hirsutellones have grabbed the

New depsidones and isoindolinones from the mangrove endophytic fungus Meyerozyma guilliermondii (HZ-Y₂) isolated from the South China Sea

• Senhua Chen,
• Zhaoming Liu,
• Yayue Liu,
• Yongjun Lu,
• Lei He and
• Zhigang She

Beilstein J. Org. Chem. 2015, 11, 1187–1193, doi:10.3762/bjoc.11.133

• of bioactivities including antibacterial [10], antifungal [6], antiviral [12], antioxidant [5], and cytotoxic [9]. In the last decade, our research group has been focused on isolating novel compounds from endophytic fungi growing on mangroves in the South China Sea and investigating their bioactivity

• ). In the bioactivity assay, all depsidones showed strong α-glucosidase inhibitory activity with IC50 values ranging from 2.1 to 13.3 μM. Details of the isolation, structure elucidation, and biological activity of these compounds are reported herein. Results and Discussion Botryorhodine E (1) was

Gold-catalyzed formation of pyrrolo- and indolo-oxazin-1-one derivatives: The key structure of some marine natural products

• Sultan Taskaya,
• Nurettin Menges and
• Metin Balci

Beilstein J. Org. Chem. 2015, 11, 897–905, doi:10.3762/bjoc.11.101

• synthesis of pharmaceutically relevant building blocks has always been a significant goal in organic synthesis. Moreover, modification of natural products is also an important approach to identify promising anticancer agents. Especially due to the bioactivity of lukianols, many groups accomplished the

Regulation of integrin and growth factor signaling in biomaterials for osteodifferentiation

• Qiang Wei,
• Theresa L. M. Pohl,
• Anja Seckinger,
• Joachim P. Spatz and
• Elisabetta A. Cavalcanti-Adam

Beilstein J. Org. Chem. 2015, 11, 773–783, doi:10.3762/bjoc.11.87

• higher bioactivity compared to their corresponding homodimers [57]. BMP receptors (BMPRs) belong to the group of serine/threonine kinase transmembrane receptors and are subdivided into type I and II receptors [64][65]. There are three type I receptors, namely BMPR-IA (also known as ALK-3, activin

Synthesis of the furo[2,3-b]chromene ring system of hyperaspindols A and B

• Danielle L. Paterson and
• David Barker

Beilstein J. Org. Chem. 2015, 11, 265–270, doi:10.3762/bjoc.11.29

• hepatitis and depression, and as topical antimicrobials for wounds and snake bites [2][3][4][5]. There is great interest in secondary metabolites produced by plants from the Hypericum genus due to the bioactivity of many compounds that have been isolated from this source. A wide variety of compounds have

Natural phenolic metabolites with anti-angiogenic properties – a review from the chemical point of view

• Qiu Sun,
• Jörg Heilmann and
• Burkhard König

Beilstein J. Org. Chem. 2015, 11, 249–264, doi:10.3762/bjoc.11.28

• bioactivity of the natural compounds are typically limited. Thus far, no example of very strong anti-angiogenic activity in the nanomolar range has been found. Thus, synthetic approaches for the production, diversification and optimization are required. The modification of the polyphenol structures to improve

• their stability and bioactivity and further enhance their anti-angiogenic activity is the main goal of current research in the field. Analogs of the natural phenols with improved drug properties may be promising candidates for future oncology treatment. Structure of 4-hydroxybenzyl alcohol (HBA, 1