Morpholine-mediated defluorinative cycloaddition of gem-difluoroalkenes and organic azides

• Tzu-Yu Huang,
• Mario Djugovski,
• Sweta Adhikari,
• Destinee L. Manning and
• Sudeshna Roy

Beilstein J. Org. Chem. 2023, 19, 1545–1554, doi:10.3762/bjoc.19.111

• , entries 6 and 7) resulted in poor yields. Since the gem-difluoroalkenes are volatile compounds and as we observed decomposition of the azides at high temperatures resulting in reduced yields, we wanted to monitor the temperature and time course of this reaction. The time course study was carried out via

Identification and determination of the absolute configuration of amorph-4-en-10β-ol, a cadinol-type sesquiterpene from the scent glands of the African reed frog Hyperolius cinnamomeoventris

• Angelique Ladwig,
• Markus Kroll and
• Stefan Schulz

Beilstein J. Org. Chem. 2023, 19, 167–175, doi:10.3762/bjoc.19.16

• Angelique Ladwig Markus Kroll Stefan Schulz Institute of Organic Chemistry, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany 10.3762/bjoc.19.16 Abstract Hyperolid reed frogs are one of the few families of Anurans known to possess glands that emit volatile compounds

Volatile emission and biosynthesis in endophytic fungi colonizing black poplar leaves

• Christin Walther,
• Pamela Baumann,
• Katrin Luck,
• Beate Rothe,
• Peter H. W. Biedermann,
• Jonathan Gershenzon,
• Tobias G. Köllner and
• Sybille B. Unsicker

Beilstein J. Org. Chem. 2021, 17, 1698–1711, doi:10.3762/bjoc.17.118

• , Cladosporium, Fusarium, Sordaria, and Stemphylium (Table 1). One unidentified species was also included in the volatile analysis. All the identified fungi belong to the Ascomycota, the largest fungal phylum. Endophytic fungi emit typical plant VOCs Altogether, we detected 77 volatile compounds in the

• headspaces of the 13 different endophytic species grown on agar medium. With 34 different compounds, the unidentified fungus was the endophyte emitting the most complex volatile blend. In contrast, in the headspace of both Stemphylium sp. and Cladosporium sp., only two volatile compounds were detected (Table

•  2). All endophytic fungi, except Cladosporium sp., produced aliphatic or aromatic alcohols like 2-methyl-1-propanol (7), 3-methyl-1-butanol (6) or 2-phenylethanol (3). Of 77 detected volatile compounds, 50 compounds are sesquiterpenes. Furthermore, seven out of 13 fungi produced sesquiterpenes. In

Valorisation of plastic waste via metal-catalysed depolymerisation

• Francesca Liguori,
• Carmen Moreno-Marrodán and
• Pierluigi Barbaro

Beilstein J. Org. Chem. 2021, 17, 589–621, doi:10.3762/bjoc.17.53

• material rather than the material itself, and it is usually achieved by combustion or incineration [61][62]. This method is generally used for plastics that cannot be economically recycled by other means [63][64]. However, it often entails the emission of toxic volatile compounds (furans, dioxins) [65

• products, such as coffee cups or take-away containers, can be recycled into videocassette cases or office equipment. Incineration at a temperature below 1000 °C and insufficient air is believed to produce a mixture of volatile compounds, including hazardous polycyclic aromatic hydrocarbons, alkylbenzenes

• of these features, PLA is largely employed in several applications: microelectronics, biomedicine and food packaging [260]. Although chemical recycling of PLA is possible by thermal methods over metal catalysts [261][262], these often result in a poor selectivity and in a variety of volatile

A new and efficient methodology for olefin epoxidation catalyzed by supported cobalt nanoparticles

• Lucía Rossi-Fernández,
• Viviana Dorn and
• Gabriel Radivoy

Beilstein J. Org. Chem. 2021, 17, 519–526, doi:10.3762/bjoc.17.46

• internal reference. Mass spectra (EI) were obtained at 70 eV on a Agilent HP-7890B GC/MS instrument equipped with a Agilent 5977A selective mass detector. Infrared (FTIR) spectra were obtained on a Nicolet-Nexus spectrophotometer. The purity of volatile compounds and the chromatographic analyses (GC) were

Identification of volatiles from six marine Celeribacter strains

• Anuj Kumar Chhalodia,
• Jan Rinkel,
• Dorota Konvalinkova,
• Jörn Petersen and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2021, 17, 420–430, doi:10.3762/bjoc.17.38

• ) C. manganoxidans DSM 27541T, D) C. baekdonensis DSM 27375T, E) C. halophilus DSM 26270T, and F) C. indicus DSM 27257T. Peaks arising from known contaminants are indicated by asterisks. Structures of the identified volatile compounds in the headspace extracts from six Celeribacter type strains. EI

On the mass spectrometric fragmentations of the bacterial sesterterpenes sestermobaraenes A–C

• Anwei Hou and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2020, 16, 2807–2819, doi:10.3762/bjoc.16.231

• water, simple alcohols. These volatile compounds can efficiently be trapped by specialised methods including the closed-loop stripping apparatus (CLSA) [4] technique or solid-phase microextraction (SPME) [5][6], and then analysed by gas chromatography–mass spectrometry (GC–MS) [7]. Through these and

3-Acetoxy-fatty acid isoprenyl esters from androconia of the ithomiine butterfly Ithomia salapia

• Florian Mann,
• Daiane Szczerbowski,
• Lisa de Silva,
• Melanie McClure,
• Marianne Elias and
• Stefan Schulz

Beilstein J. Org. Chem. 2020, 16, 2776–2787, doi:10.3762/bjoc.16.228

• double bond isomers were detected. Nevertheless, differences were present in the minor components and more volatile compounds (Table 1). Sesquiterpene 8 is restricted to I. s. derasa, whereas ithomiolide A (3) was present exclusively in some of the I. s. aquinia samples. C16-isoprenyl esters are only

Analysis of sesquiterpene hydrocarbons in grape berry exocarp (Vitis vinifera L.) using in vivo-labeling and comprehensive two-dimensional gas chromatography–mass spectrometry (GC×GC–MS)

• Philipp P. Könen and
• Matthias Wüst

Beilstein J. Org. Chem. 2019, 15, 1945–1961, doi:10.3762/bjoc.15.190

• headspace using a mixed fiber, the volatile and semi-volatile compounds were desorbed in the GC inlet at 250 °C for 5 min. In order to avoid carryover, the fiber was reconditioned for 15 min at 250 °C prior to each analysis. No sample carryover was observed. GC×GC–TOF–MS analysis All chromatographic

• -labeled compounds starting from the precursors d3-MVL and d2-DOX after incubation. Contour plot of a HS-SPME–GC×GC–TOF–MS chromatogram (TIC) demonstrating the separation of volatile compounds isolated from the headspace of grape berries of the red wine variety Lemberger (Vitis vinifera subsp. vinifera

• compound numbers as defined in Figure 2 and Table 1. The area framed in red including the volatile compounds numbered 10, 3 and 5 is enlarged in Figure 3. Sesquiterpene hydrocarbons found in the headspace of Lemberger (Vitis vinifera subsp. vinifera, clone 1Gm, exocarp). 1–4, monocyclic sesquiterpenes; 5

New terpenoids from the fermentation broth of the edible mushroom Cyclocybe aegerita

• Frank Surup,
• Florian Hennicke,
• Nadine Sella,
• Maria Stroot,
• Steffen Bernecker,
• Sebastian Pfütze,
• Marc Stadler and
• Martin Rühl

Beilstein J. Org. Chem. 2019, 15, 1000–1007, doi:10.3762/bjoc.15.98

• strains, targeting both volatile and non-volatile compounds. The present paper will describe the discovery of one known and three new non-volatile terpenoids (Figure 1) that were isolated from liquid cultures of C. aegerita and their physicochemical and preliminary biological characterisation. Results and

Unnatural α-amino ethyl esters from diethyl malonate or ethyl β-bromo-α-hydroxyiminocarboxylate

• Eloi P. Coutant,
• Vincent Hervin,
• Glwadys Gagnot,
• Candice Ford,
• Racha Baatallah and
• Yves L. Janin

Beilstein J. Org. Chem. 2018, 14, 2853–2860, doi:10.3762/bjoc.14.264

• equilibration between the two forms was reported [28] to be a slow process, it would potentially lead to decomposition materials. In any case, as depicted in Table 2, from the commercially available furans 48af–an or from crude solutions of the less accessible (and volatile) compounds 48ao–ar (their preparation

Acyl-group specificity of AHL synthases involved in quorum-sensing in Roseobacter group bacteria

• Lisa Ziesche,
• Jan Rinkel,
• Jeroen S. Dickschat and
• Stefan Schulz

Beilstein J. Org. Chem. 2018, 14, 1309–1316, doi:10.3762/bjoc.14.112

• on surfaces [3]. They can produce a variety of secondary metabolites, including antibiotics [4][5], volatile compounds [6][7], oligohydroxybutyrates [8] and a range of N-acylhomoserine lactones (AHLs) [8][9][10]. AHLs are quorum-sensing signaling compounds that are used for cell–cell communication to

Volatiles from the xylarialean fungus Hypoxylon invadens

• Jeroen S. Dickschat,
• Tao Wang and
• Marc Stadler

Beilstein J. Org. Chem. 2018, 14, 734–746, doi:10.3762/bjoc.14.62

• in fungi [34]. Conclusion The genus Hypoxylon has already been examined extensively for secondary metabolite production, and some of its species like H. pulicicidum and H. rickii are extremely creative with respect to the production of non-volatile compounds [35][36][37]. The current study is the

Latest development in the synthesis of ursodeoxycholic acid (UDCA): a critical review

• Fabio Tonin and
• Isabel W. C. E. Arends

Beilstein J. Org. Chem. 2018, 14, 470–483, doi:10.3762/bjoc.14.33

• . Ideally, there is the possibility of using other types of less volatile compounds but no reports thereof have been found. 12α-Hydroxysteroid dehydrogenase 12α-Hydroxysteroid dehydrogenases (12α-HSDH) are particularly interesting for the selective oxidation of the 12-hydroxy group of CA (Figure 4). These

Identification, synthesis and mass spectrometry of a macrolide from the African reed frog Hyperolius cinnamomeoventris

• Markus Menke,
• Pardha Saradhi Peram,
• Iris Starnberger,
• Walter Hödl,
• Gregory F.M. Jongsma,
• David C. Blackburn,
• Mark-Oliver Rödel,
• Miguel Vences and
• Stefan Schulz

Beilstein J. Org. Chem. 2016, 12, 2731–2738, doi:10.3762/bjoc.12.269

• volatile compounds during courtship are the African reed frogs, Hyperoliidae. The males of most species emit acoustic cues to attract females. During the call, an often conspicuously colored gland on their vocal sac (the gular gland), only innervated during the mating season in at least some species

Towards potential nanoparticle contrast agents: Synthesis of new functionalized PEG bisphosphonates

• Souad Kachbi-Khelfallah,
• Maelle Monteil,
• Margery Cortes-Clerget,
• Evelyne Migianu-Griffoni,
• Jean-Luc Pirat,
• Olivier Gager,
• Julia Deschamp and
• Marc Lecouvey

Beilstein J. Org. Chem. 2016, 12, 1366–1371, doi:10.3762/bjoc.12.130

• (trimethylsilyl) phosphite to the acyl chloride derivatives 8 and 9a,b yielded the corresponding silylated PEG-HMBP. The formation of silylated bisphosphonate was monitored by 31P NMR. After evaporation of volatile compounds under vacuum the silylated PEG-HMBP was hydrolyzed with methanol at room temperature for

Thermal and oxidative stability of Atlantic salmon oil (Salmo salar L.) and complexation with β-cyclodextrin

• Daniel I. Hădărugă,
• Mustafa Ünlüsayin,
• Alexandra T. Gruia,
• Cristina Birău (Mitroi),
• Gerlinde Rusu and
• Nicoleta G. Hădărugă

Beilstein J. Org. Chem. 2016, 12, 179–191, doi:10.3762/bjoc.12.20

• TG and DSC provide information on the releases of volatile compounds and on the energetic effect of these processes (as well as other ones), but no differentiation between compounds can be established. On the other hand, KFT provides a selective determination for water. Consequently, the correlation

Two strategies for the synthesis of the biologically important ATP analogue ApppI, at a multi-milligram scale

• Janne Weisell,
• Jouko Vepsäläinen and
• Petri A. Turhanen

Beilstein J. Org. Chem. 2015, 11, 2189–2193, doi:10.3762/bjoc.11.237

• (15 mL), dry Na2CO3 (2.15 g, 20.3 mmol) and 3-methyl-3-buten-1-ol (2.25 mL, 1.91 g, 22.2 mmol) were added and the reaction mixture was stirred for 7 days at 50 °C. The reaction mixture was evaporated to dryness and dissolved in diethyl ether (20 mL), filtered and volatile compounds were removed in

Thermal and oxidative stability of the Ocimum basilicum L. essential oil/β-cyclodextrin supramolecular system

• Daniel I. Hădărugă,
• Nicoleta G. Hădărugă,
• Corina I. Costescu,
• Ioan David and
• Alexandra T. Gruia

Beilstein J. Org. Chem. 2014, 10, 2809–2820, doi:10.3762/bjoc.10.298

• –uncomplexed volatile compounds in an ethanol/water solution at 50 °C. Both the raw essential oil and its β-CD complex have been subjected to thermal and oxidative degradation conditions in order to evaluate the protective capacity of β-CD. The relative concentration of the O. basilicum L. essential oil

• increase of the relative concentration of linalool oxide from 0.3% to 1.1%, in addition to many sesquiterpene oxides, has been observed. β-CD complexation of the O. basilicum essential oil modifies the relative concentration of the encapsulated volatile compounds. Thus, linalool was better encapsulated in

• concentrations of volatile compounds (essential oils or volatile oils), among other compounds (e.g., flavonoids) [10], which furnish different flavoring and medicinal properties, such as antimicrobial, anti-inflammatory, analgesic, or antiseptic properties [11][12][13][14], in addition to antifungal and insect

Streptopyridines, volatile pyridine alkaloids produced by Streptomyces sp. FORM5

• Ulrike Groenhagen,
• Michael Maczka,
• Jeroen S. Dickschat and
• Stefan Schulz

Beilstein J. Org. Chem. 2014, 10, 1421–1432, doi:10.3762/bjoc.10.146

• components. In the gas phase, only the streptopyridines could be detected. Therefore, an orthogonal set of analysis is needed to assess the metabolic profile of bacteria, because volatile compounds are obviously overlooked by traditional analytical methods. The streptopyridines are strain specific volatiles

• . Keywords: headspace analysis; natural products; polyketide biosynthesis; pyridine derivatives; streptazolin; volatile compounds; Introduction Actinomycetes are excellent producers of diverse and bioactive secondary metabolites. These metabolites belong to many different structural classes including

• hydrogen bonding with water obviously prevent release from the water phase in substantial amounts. Volatile compounds like the streptopyridines are less soluble, have a lower basicity and can be detected as major compounds in the headspace. Both analytical methods have a different analytical window and

Structure elucidation of female-specific volatiles released by the parasitoid wasp Trichogramma turkestanica (Hymenoptera: Trichogrammatidae)

• Armin Tröger,
• Teris A. van Beek,
• Martinus E. Huigens,
• Isabel M. M. S. Silva,
• Maarten A. Posthumus and
• Wittko Francke

Beilstein J. Org. Chem. 2014, 10, 767–773, doi:10.3762/bjoc.10.72

• about (volatile) semiochemicals playing a role in intraspecific communication [7][8][9][10][11]. Based on bioassays with Trichogramma turkestanica and extensive analytical investigations, two female-specific volatile compounds have been described as possible pheromone components and were tentatively

Halogenated volatiles from the fungus Geniculosporium and the actinomycete Streptomyces chartreusis

• Tao Wang,
• Patrick Rabe,
• Christian A. Citron and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2013, 9, 2767–2777, doi:10.3762/bjoc.9.311

• haloperoxidases [19]. Here we report on the identification of two chlorinated volatile compounds from the fungus Geniculosporium and a iodinated volatile from Streptomyces chartreusis. Results and Discussion Chlorinated volatiles from Geniculosporium The volatiles emitted by agar plate cultures of the fungus

Formation of carbohydrate-functionalised polystyrene and glass slides and their analysis by MALDI-TOF MS

• Martin J. Weissenborn,
• Johannes W. Wehner,
• Christopher J. Gray,
• Robert Šardzík,
• Claire E. Eyers,
• Thisbe K. Lindhorst and
• Sabine L. Flitsch

Beilstein J. Org. Chem. 2012, 8, 753–762, doi:10.3762/bjoc.8.86

• preactivated 11-tritylsulfanylundecanoic acid (3) was cooled to 0 °C, the solution of mannoside 4 was added and the resulting mixture was stirred under a nitrogen atmosphere at ambient temperature overnight. All volatile compounds were removed under reduced pressure and the crude product was subjected to MPLC

• added to the preactivated 11-tritylsulfanylundecanoic acid (3) and it was stirred under a nitrogen atmosphere at ambient temperature for 3 h. All volatile compounds were removed under reduced pressure and the crude product was subjected to MPLC (50 g silica column, A: dichloromethane, B: methanol, A: 99

Volatile organic compounds produced by the phytopathogenic bacterium Xanthomonas campestris pv. vesicatoria 85-10

• Teresa Weise,
• Marco Kai,
• Anja Gummesson,
• Armin Troeger,
• Stephan von Reuß,
• Silvia Piepenborn,
• Francine Kosterka,
• Martin Sklorz,
• Ralf Zimmermann,
• Wittko Francke and
• Birgit Piechulla

Beilstein J. Org. Chem. 2012, 8, 579–596, doi:10.3762/bjoc.8.65

• ][24][25], which influence the growth of fungi [22][23][26][27]. In most cases the bacterial volatiles showed inhibitory activities (reviewed in [20]). We, therefore, hypothesized that volatile compounds emitted by Xanthomonas campestris pv. vesicatoria 85-10 may also play a role as antagonistic

• ][41]. Dodecan-2-one (38) was found among the volatiles of Serratia strains [41], and decan-2-one (28) was released by an epilithic cyanobacterial biofilm of Rivularia sp. and Calothrix parietina [42]. The main component among the volatile compounds released by X. c. pv. vesicatoria 85-10, namely 10

• volatile compounds emitted by X. c. pv. vesicatoria 85-10, shows a close biogenetic relation to 11-methyldodec-2Z-enoic acid (compound V in Scheme 2), which has been described earlier as a metabolite produced by Xanthomonas [13]. Possible biogenetic pathways to the two compounds are shown in Scheme 2

The volatiles of pathogenic and nonpathogenic mycobacteria and related bacteria

• Thorben Nawrath,
• Georgies F. Mgode,
• Bart Weetjens,
• Stefan H. E. Kaufmann and
• Stefan Schulz

Beilstein J. Org. Chem. 2012, 8, 290–299, doi:10.3762/bjoc.8.31

• , and N. asteroides, using closed-loop stripping analysis (CLSA) for the collection of volatile compounds [15][16]. This method allows sampling for longer periods than SPME, and usually results in a lower detection limit. Compounds not detectable by SPME can thus be detected. SPME preferentially favors

• less volatile compounds [17]. Furthermore, SPME may have a discriminative effect, and our experience has shown that minor components are often not detected when large amounts of a major component are present. The investigated mycobacteria were in different stages of their lifecycles and grown on

• many mycobacteria [7][20]. Increased production of volatile compounds occurred in the stationary phase (i.e., starting after three weeks of growth), a phenomenon that corroborates the recent findings that M. tuberculosis culture is detected by trained rats mostly at this growth stage [20]. A full