Confirmation of the stereochemistry of spiroviolene

• Yao Kong,
• Yuanning Liu,
• Kaibiao Wang,
• Tao Wang,
• Chen Wang,
• Ben Ai,
• Hongli Jia,
• Guohui Pan,
• Min Yin and
• Zhengren Xu

Beilstein J. Org. Chem. 2024, 20, 852–858, doi:10.3762/bjoc.20.77

• be produced by feeding prenol and/or isoprenol to the fermentation broth after E. coli being induced by IPTG, and fermented at 18 °C for 72 h. In our hand, feeding a mixture of prenol and isoprenol in a 1:1 ratio would give the best yield of spiroviolene. GC–MS analysis (Figure 2A) of the EtOAc

Genome mining of labdane-related diterpenoids: Discovery of the two-enzyme pathway leading to (−)-sandaracopimaradiene in the fungus Arthrinium sacchari

• Fumito Sato,
• Terutaka Sonohara,
• Shunta Fujiki,
• Akihiro Sugawara,
• Yohei Morishita,
• Taro Ozaki and
• Teigo Asai

Beilstein J. Org. Chem. 2024, 20, 714–720, doi:10.3762/bjoc.20.65

• File 1, Figure S3). The purified proteins were incubated in the presence of GGPP and Mg2+. GC–MS analysis of the hexane extract revealed the enzyme-dependent formation of compound 1 (Figure 4A and Figure S2 in Supporting Information File 1). The formation of 1 was not observed when either AsPS or AsCPS

• GGPP, followed by hydrolysis by acid phosphatase. GC–MS analysis revealed that AsCPS synthesizes the same product to ObCPS_11g (see Supporting Information File 1, Figure S4A and B). It should be noted that the stereochemistry of CPP needs further verification due to the lack of chiral resolution of our

• clusters containing AsCPS and AsPS. B) Domain organization of AsPS and AsCPS. C) Domain organization of CiCPS-PS. GC–MS analysis of the A. oryzae transformant. A) TIC of the extracts obtained from AO-AsGGS/AsCPS/AsPS and A. oryzae NSAR1. Compound 1 was identified to be a product, while the other minor

New variochelins from soil-isolated Variovorax sp. H002

• Jabal Rahmat Haedar,
• Aya Yoshimura and
• Toshiyuki Wakimoto

Beilstein J. Org. Chem. 2024, 20, 692–700, doi:10.3762/bjoc.20.63

• from 4 was subjected to GC–MS analysis. The EIMS spectrum showed two typical prominent ions at m/z 113 and m/z 126, as well as two ions at m/z 222 and m/z 208, corresponding to the loss of methylene groups (14 mass units). More importantly, a gap of 12 mass units between m/z 196 (C8) and 208 (C9) was

• File 1). Subsequent GC–MS analysis of the DMOX derivative allowed us to deduce the fatty acyl chain in 5 as a 7-tetradecenoic acid, confirming 5 as another new variochelin analog, variochelin E. The absolute configurations of the newly isolated congeners (3–5) were determined by Marfey’s analysis [17

Functions of enzyme domains in 2-methylisoborneol biosynthesis and enzymatic synthesis of non-natural analogs

• Binbin Gu,
• Lin-Fu Liang and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2023, 19, 1452–1459, doi:10.3762/bjoc.19.104

• products that have been identified by GC–MS analysis and the synthesis of reference compounds [30][31]. Notably, 2MIBS also shows some substrate flexibility and can convert GPP into monoterpenes in vitro, albeit with less efficiency as compared to the conversion of 2-Me-GPP [24]. On the other hand, single

• intestinal phosphatase (CIP), followed by extraction of the reaction mixture with hexane and GC–MS analysis. Several combinations of DMAPP and IPP analogs resulted in a good production of the corresponding GPP analogs (indicated by three black plus signs in Table 1). Other combinations gave a medium (++) or

Functional characterisation of twelve terpene synthases from actinobacteria

• Anuj K. Chhalodia,
• Houchao Xu,
• Georges B. Tabekoueng,
• Binbin Gu,
• Kizerbo A. Taizoumbe,
• Lukas Lauterbach and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2023, 19, 1386–1398, doi:10.3762/bjoc.19.100

• , Supporting Information File 1), suggesting that it could have a different function. The incubation with FPP yielded 7-epi-α-eudesmol (23) as the main product, besides germacrene A (24) and hedycaryol (26) that were detected by their Cope rearrangement products elemene (25) and elemol (27) formed during GC–MS

• analysis (Figure 6 and Scheme 1A). These compounds are also observed with 7-epi-α-eudesmol synthase from S. viridochromogenes, demonstrating that the phylogenetic distance of the enzyme from S. flavidovirens is not associated with a different enzyme function. The conversion of GPP gave only trace amounts

Photoredox catalysis harvesting multiple photon or electrochemical energies

• Mattia Lepori,
• Simon Schmid and
• Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

Discrimination of β-cyclodextrin/hazelnut (Corylus avellana L.) oil/flavonoid glycoside and flavonolignan ternary complexes by Fourier-transform infrared spectroscopy coupled with principal component analysis

• Nicoleta G. Hădărugă,
• Gabriela Popescu,
• Dina Gligor (Pane),
• Cristina L. Mitroi,
• Sorin M. Stanciu and
• Daniel Ioan Hădărugă

Beilstein J. Org. Chem. 2023, 19, 380–398, doi:10.3762/bjoc.19.30

• until GC–MS analysis. GC–MS analysis was performed on a GC Hewlett Packard 6890 Series equipment, coupled with a Hewlett Packard 5973 Mass Selective Detector. The following GC conditions were used: Zebron 5-MS column (30 m length, 0.25 mm i.d., 0.25 µm film thickness), temperature program of 50–300 °C

Sequential hydrozirconation/Pd-catalyzed cross coupling of acyl chlorides towards conjugated (2E,4E)-dienones

• Benedikt Kolb,
• Daniela Silva dos Santos,
• Sanja Krause,
• Anna Zens and
• Sabine Laschat

Beilstein J. Org. Chem. 2023, 19, 176–185, doi:10.3762/bjoc.19.17

• and HPLC purification steps. However, GC–MS analysis of the crude product of one exemplary dienone 27ac (with only 17% yield) indicated only decomposition in the reaction sequence. Further, phenylenyne 25a was treated with different conjugated and aliphatic acyl chlorides 26m–p (Table 4, entries 13–16

Characterization of a new fusicoccane-type diterpene synthase and an associated P450 enzyme

• Jia-Hua Huang,
• Jian-Ming Lv,
• Liang-Yan Xiao,
• Qian Xu,
• Fu-Long Lin,
• Gao-Qian Wang,
• Guo-Dong Chen,
• Sheng-Ying Qin,
• Dan Hu and
• Hao Gao

Beilstein J. Org. Chem. 2022, 18, 1396–1402, doi:10.3762/bjoc.18.144

• ]. The resulted transformant was cultivated in the modified Czapek–Dox medium for four days, and then mycelia were harvested and extracted for analysis. Upon gas chromatography-mass spectrometry (GC–MS) analysis, we observed an additional peak at m/z = 272 [M]+ from the tadA harboring transformant

• with or without addition of deuterated water (D2O). GC–MS analysis showed that when the reaction mixture was supplemented with D2O, the ion peak at m/z 273 was observed, indicating that exogenous deuterium was incorporated into 1 (Supporting Information File 1, Figure S19). This suggests that TadA

From amines to (form)amides: a simple and successful mechanochemical approach

• Federico Casti,
• Rita Mocci and
• Andrea Porcheddu

Beilstein J. Org. Chem. 2022, 18, 1210–1216, doi:10.3762/bjoc.18.126

• intermediate was not detected by NMR or GC–MS analysis, possibly due to its instability [64]. Several studies carried out on our reaction crude at different times did not show the presence of compounds traceable to formylimidazole. The imidazole plays a dual role as promoting reagent and solid grinding

The stereochemical course of 2-methylisoborneol biosynthesis

• Binbin Gu,
• Anwei Hou and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2022, 18, 818–824, doi:10.3762/bjoc.18.82

• by GC/MS analysis and synthesis of reference compounds [29], several of which also occur in Escherichia coli or yeast strains that were engineered for the biosynthesis of methylated monoterpenes derived from 2-Me-GPP [30][31]. About one decade ago, the crystal structures of GPPMT and 2MIBS have been

• enriched 2-Me-LPP with 2-MIBS The enantiomerically enriched substrates (R)- and (S)-2-Me-LPP were incubated with purified 2MIBS (Figure S2 in Supporting Information File 1), followed by extraction of the enzyme reactions with hexane and GC/MS analysis of the obtained products (Figure S3, Table S1 in

• enantiomerically pure 2-Me-LPP with 2-MIBS Both pure enantiomers of 2-Me-LPP were incubated with 2-MIBS. GC/MS analysis of the products (Figure 3A and 3B, and Table S1 in Supporting Information File 1) showed with the substrate (R)-2-Me-LPP an efficient conversion into 2-methylisoborneol (1, 75%). Minor compounds

Synthesis of α-(perfluoroalkylsulfonyl)propiophenones: a new set of reagents for the light-mediated perfluoroalkylation of aromatics

• Durbis J. Castillo-Pazos,
• Juan D. Lasso and
• Chao-Jun Li

Beilstein J. Org. Chem. 2022, 18, 788–795, doi:10.3762/bjoc.18.79

• 2-(perfluorohexyl)-1,1-diphenylethylene (8), and propiophenone through GC–MS analysis. Additionally, the presence of free SO2 gas was confirmed by the reaction of acidic potassium dichromate solution on paper (green coloration of the exposed surface). See Supporting Information File 1 for details

• as N-phenylpyrrole and 2-phenylindole were found to produce large quantities of the desired perfluorohexyl and perfluorooctyl analogues as observed by both 1H NMR and GC–MS analysis. However, these molecules generated large concentrations of fluorinated byproducts which rendered separation of the

Synthesis of odorants in flow and their applications in perfumery

• Merlin Kleoff,
• Paul Kiler and
• Philipp Heretsch

Beilstein J. Org. Chem. 2022, 18, 754–768, doi:10.3762/bjoc.18.76

• temperature of 70 °C and a residence time of 30 min, macrocycles 65 and 66 are obtained in excellent yields with a preference for the E-isomers as determined by GC/MS analysis. Although, macrocycles 65 and 66 are, to the best of our knowledge, not used as musks in perfumery, this work demonstrates the value

A trustworthy mechanochemical route to isocyanides

• Francesco Basoccu,
• Federico Cuccu,
• Federico Casti,
• Rita Mocci,
• Claudia Fattuoni and
• Andrea Porcheddu

Beilstein J. Org. Chem. 2022, 18, 732–737, doi:10.3762/bjoc.18.73

• (GC–MS analysis). Unexpectedly, the addition of Lewis acids, namely LiCl and BF3·Et2O, did not improve the enolate generation. The next step was searching the optimal conditions for a better conversion of 1f in 2f. These were found in the 1:2:7 ratios of the three components with the addition of 400

• after 1h (70%, GC–MS analysis). Reducing the amount of sodium carbonate did not provide any advantage. Interestingly, using anhydrous sodium carbonate instead of its hydrated form improved reaction yields, likely due to the hydrolysis of tosyl chloride. With these data in hand, we then opted for

Terpenoids from Glechoma hederacea var. longituba and their biological activities

• Dong Hyun Kim,
• Song Lim Ham,
• Zahra Khan,
• Sun Yeou Kim,
• Sang Un Choi,
• Chung Sub Kim and
• Kang Ro Lee

Beilstein J. Org. Chem. 2022, 18, 555–566, doi:10.3762/bjoc.18.58

• spectrum of 1S,4S,5R,8S,10R-(1a). Finally, the ᴅ-glucopyranosyl moiety was identified by GC–MS analysis of a chiral derivatization product of the sugar obtained by enzyme hydrolysis of 1 [9][10]. The retention time of glucopyranose (11.3 min) corresponded to that of the standard ᴅ-glucopyranose (11.3 min

• as 3α,12α,16α [15]. Finally, the ᴅ-glucopyranose unit in 4 was confirmed by GC–MS analysis as described above (Supporting Information File 1, Figure S35) [10], and the coupling constant of anomeric protons at δH 4.33 (J = 7.8 Hz) implied β-ᴅ-glucopyranose [16]. Thus, the structure of compound 4 was

• ), the reaction mixture was allowed to react again at 60 °C for 2 h. The reactant was suspended in distilled H2O (1 mL) and then partitioned with n-hexane (1 mL). The n-hexane soluble layer was analyzed using GC–MS analysis. All monosaccharides were detected at 11.3 min, the same detection time (11.3 min

A resorcin[4]arene hexameric capsule as a supramolecular catalyst in elimination and isomerization reactions

• Tommaso Lorenzetto,
• Fabrizio Fabris and
• Alessandro Scarso

Beilstein J. Org. Chem. 2022, 18, 337–349, doi:10.3762/bjoc.18.38

• spectra were acquired at 298 K with a Bruker AVANCE 300 spectrometer operating at 300.15 MHz and with a Bruker 400 spectrometer operating at 400.15 MHz. The chemical shift values (δ) in ppm refer to SiMe4 (TMS) as standard. For GC–MS analysis a GC Trace GC 2000 apparatus was used equipped with an HP5-MS

Recent advances in the tandem annulation of 1,3-enynes to functionalized pyridine and pyrrole derivatives

• Yi Liu,
• Puying Luo,
• Yang Fu,
• Tianxin Hao,
• Xuan Liu,
• Qiuping Ding and
• Yiyuan Peng

Beilstein J. Org. Chem. 2021, 17, 2462–2476, doi:10.3762/bjoc.17.163

• standard conditions could inhibit the formation of target product. In contrast, the compound TEMPO–N3 was detected by GC–MS analysis. Based on the radical trapping experiment and previous reports, the reaction may undergo a radical process. 2-Carbonylpyrrole is a key subunit of many bioactive natural

Phenolic constituents from twigs of Aleurites fordii and their biological activities

• Kyoung Jin Park,
• Won Se Suh,
• Da Hye Yoon,
• Chung Sub Kim,
• Sun Yeou Kim and
• Kang Ro Lee

Beilstein J. Org. Chem. 2021, 17, 2329–2339, doi:10.3762/bjoc.17.151

• demethyldihydrodehydrodiconiferyl alcohol based on the comparison of 1H NMR and MS data [13]. The relatively large coupling constant of the anomeric proton (7.8 Hz) confirmed that the glucose is combined as β-form [14]. ᴅ-Glucose was identified by co-TLC with a standard sample [CHCl3/MeOH/H2O 2:1:0.1, Rf = 0.3)] and GC–MS analysis

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

• Guido Gambacorta,
• James S. Sharley and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90

Selective synthesis of α-organylthio esters and α-organylthio ketones from β-keto esters and sodium S-organyl sulfurothioates under basic conditions

• Jean C. Kazmierczak,
• Roberta Cargnelutti,
• Thiago Barcellos,
• Claudio C. Silveira and
• Ricardo F. Schumacher

Beilstein J. Org. Chem. 2021, 17, 234–244, doi:10.3762/bjoc.17.24

• results by Bolm et al. [45] and Wang et al. [47], we turned to conduct the reaction under an oxygen atmosphere (Table 1, entry 22). To our delight, the product 3a was obtained selectively in 86% yield. In this case, even GC–MS analysis of the crude sample did not show the presence of 4a. With the best

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

• terpene fragmentations in EIMS in the future by the strategy applied in this work to learn more about the underlying reaction mechanisms. Experimental Preparation of 13C-labelled compounds 1–3 and GC–MS analysis The 25 isotopomers of (13C)-1, (13C)-2, and (13C)-3 were prepared enzymatically with SmTS1

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

• formed from hedycaryol (7) during GC/MS analysis by a Cope-rearrangement [20][21], indicating that 7 might be originally present in the hairpencils. That said, we cannot disprove that this rearrangement could also occur in the androconia. Hedycaryol is an early product of sesquiterpene biosynthesis

Aldehydes as powerful initiators for photochemical transformations

• Maria A. Theodoropoulou,
• Nikolaos F. Nikitas and
• Christoforos G. Kokotos

Beilstein J. Org. Chem. 2020, 16, 833–857, doi:10.3762/bjoc.16.76

• fluorescence quenching studies, UV–vis spectroscopy experiments, calculation of the quantum yield, a cutoff experiment below 400 nm, GC–MS analysis, and NMR spectroscopic mechanistic experiments. They also concluded that an energy transfer mechanism could not be possible since the solvent employed affected the

Photocatalytic deaminative benzylation and alkylation of tetrahydroisoquinolines with N-alkylpyrydinium salts

• David Schönbauer,
• Carlo Sambiagio,
• Timothy Noël and
• Michael Schnürch

Beilstein J. Org. Chem. 2020, 16, 809–817, doi:10.3762/bjoc.16.74

• after 60 h reaction time (34 and 35). For the cyclohexylation the yield was even lower and conversion stopped after 48 h (26%, 36). When [Ru(bpy)3]Cl2 was used as the catalyst, GC–MS analysis of the crude material showed considerably less conversion in comparison. We found that Katritzky salts deriving

Synthesis of disparlure and monachalure enantiomers from 2,3-butanediacetals

• Adam Drop,
• Hubert Wojtasek and
• Bożena Frąckowiak-Wojtasek

Beilstein J. Org. Chem. 2020, 16, 616–620, doi:10.3762/bjoc.16.57

• of the Wittig reaction. Supporting Information Supporting Information File 239: Experimental procedures of the synthesized compounds. Supporting Information File 240: Copies of 1H NMR and 13C NMR spectra. Acknowledgements We thank Dr Marietta Białoń for performing the GC–MS analysis. Funding A.D