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

• the level of degradation compounds were determined by thermal methods (thermogravimetry-differential thermogravimetry, TG–DTG, and differential scanning calorimetry, DSC) and gas chromatography–mass spectrometry (GC–MS), respectively. The addition of sodium caseinate during the CD complexation of fish

• Sigma-Aldrich, St. Louis, MO, USA). Finally, 2-propanol (ACS reagent, Reag. Ph. Eur.) used for FTIR cleaning was obtained from Merck & Co., Inc., Rahway, NJ, USA. Gas chromatography–mass spectrometry (GC–MS) The FA profile of the hazelnut oil was determined by GC–MS, after derivatization to FAMEs

Recommendations for performing measurements of apparent equilibrium constants of enzyme-catalyzed reactions and for reporting the results of these measurements

• Robert N. Goldberg,
• Robert T. Giessmann,
• Peter J. Halling,
• Carsten Kettner and
• Hans V. Westerhoff

Beilstein J. Org. Chem. 2023, 19, 303–316, doi:10.3762/bjoc.19.26

• reactions would eliminate the aforementioned possible systematic error. Thus, a check on mass balance on side reaction products is recommended. If possible, it is best to measure the concentrations of all reactants. The use of modern mass spectrometry should make this possible for many reactions. Method 3

• used occasionally. NMR and mass spectrometry can also be used in equilibrium investigations. In fact, essentially any analytical method might, in principle, be made to work. But, each analytical method has possible systematic errors associated with its use. For example, if a value of a molar decadic

Investigation of cationic ring-opening polymerization of 2-oxazolines in the “green” solvent dihydrolevoglucosenone

• Solomiia Borova and
• Robert Luxenhofer

Beilstein J. Org. Chem. 2023, 19, 217–230, doi:10.3762/bjoc.19.21

• . Size exclusion chromatography and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry were performed to determine the molar mass of the resulting polymers. Our work shows clearly that the solvent is not inert under the conditions typically used for the cationic ring-opening

• polymerization process. Further work will be necessary to establish whether a living polymerization can be achieved by additional adjustments. Keywords: 2-alkyl-2-oxazolines; matrix-assisted laser desorption/ionization mass spectrometry; nuclear magnetic resonance; polymerization kinetics; Introduction

• obtained after precipitation from cold Et2O and lyophilization were analyzed by MALDI-TOF mass spectrometry (Figure 3, Figure 4, and Figures S9–S11 in Supporting Information File 1). The resulting MALDI-TOF mass spectra clearly confirm the presence of the desired polymer. The mass difference (Δm/z) between

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

• sesquiterpene A, including spectral analysis and synthesis to determine its constitution and absolute configuration. Results and Discussion High-resolution mass spectrometry (HRMS) revealed both compounds A and C to be likely sesquiterpenes because of their molecular formula of C15H26O (m/z 222.1977, calcd for

Digyalipopeptide A, an antiparasitic cyclic peptide from the Ghanaian Bacillus sp. strain DE2B

• Adwoa P. Nartey,
• Aboagye K. Dofuor,
• Kofi B. A. Owusu,
• Anil S. Camas,
• Hai Deng,
• Marcel Jaspars and
• Kwaku Kyeremeh

Beilstein J. Org. Chem. 2022, 18, 1763–1771, doi:10.3762/bjoc.18.185

• data, mass spectrometry sequence tagging, advanced Marfey’s analysis, and the GNPS molecular networking we solved the full structure of digyalipopeptide A (1). We found that compound 1 is a member of a somewhat homologous series of peptides produced as a mixture by the strain containing the same amino

• to be C51H89N7O13 based on the high resolution electrospray ionization mass spectrometry (HRESIMSMS) at m/z 1008.6610 for [M + H]+ similar to the calculated value of m/z 1008.6591 with Δ = −1.9 ppm. The molecular formula indicated 11 degrees of unsaturation and the analyses of the 13C NMR spectrum

• and repeated the structure elucidation (see Supporting Information File 1, Table S2, and Figures S30–S37). The resultant structure confirmed the structural information initially obtained from the NMR data in DMSO-d6 solvent. High-resolution ESI mass spectrometry (HRESIMS) sequence tags Furthermore

Preparation of β-cyclodextrin-based dimers with selectively methylated rims and their use for solubilization of tetracene

• Konstantin Lebedinskiy,
• Volodymyr Lobaz and
• Jindřich Jindřich

Beilstein J. Org. Chem. 2022, 18, 1596–1606, doi:10.3762/bjoc.18.170

• . Despite this, we have found mass spectrometry and combined NMR analysis to be reliable methods to prove the structure of these compounds. On NMR spectra, we paid particular attention to the H1-region, where most of our products have several doublets, which referred to the signals from each hydrogen-1 in

Solid-phase total synthesis and structural confirmation of antimicrobial longicatenamide A

• Takumi Matsumoto,
• Takefumi Kuranaga,
• Yuto Taniguchi,
• Weicheng Wang and
• Hideaki Kakeya

Beilstein J. Org. Chem. 2022, 18, 1560–1566, doi:10.3762/bjoc.18.166

• . pulmonis TP-B0596 [8]. The planar structures were determined by analyzing two-dimensional (2D) nuclear magnetic resonance (NMR) spectra and mass spectrometry (MS) data, and the absolute configurations of their component amino acids were elucidated by using highly sensitive reagents that we recently

An alternative C–P cross-coupling route for the synthesis of novel V-shaped aryldiphosphonic acids

• Stephen J. I. Shearan,
• Enrico Andreoli and
• Marco Taddei

Beilstein J. Org. Chem. 2022, 18, 1518–1523, doi:10.3762/bjoc.18.160

• mmol), 4.0 g (12.2 mmol) or 3.0 g (7.4 mmol) of substrate. Once the phosphonate esters had been successfully obtained and characterized by 1H, 31P, 13C NMR and mass spectrometry (see experimental section and Supporting Information File 1), they were then subjected to silylation and subsequent

• the viva voce examination. We thank the National Mass Spectrometry Facility (NMSF), Swansea University Medical School, for their support in obtaining the mass spectrometry data. Funding M.T. acknowledges funding from the European Union’s Horizon 2020 research and innovation program under the Marie

Synthesis of the biologically important dideuterium-labelled adenosine triphosphate analogue ApppI(d₂)

• Petri A. Turhanen

Beilstein J. Org. Chem. 2022, 18, 1466–1470, doi:10.3762/bjoc.18.153

• (d2) opens possibilities to quantitative measurements of ApppI in biological samples by mass spectrometry. The synthesized target compound ApppI(d2) was purified by high-performance counter current chromatography and characterized by 1H, 13C, and 31P NMR spectroscopy as well as high-resolution mass

• spectrometry. Keywords: ApppI; ATP; deuterium labelling; HPCCC; mevalonate pathway; NMR; synthesis; Introduction It has become clear and evident that phosphonate chemistry plays a crucial role in drug research and development [1][2][3][4]. There are several phosphonate-containing compounds under research or

Sinensiols H–J, three new lignan derivatives from Selaginella sinensis (Desv.) Spring

• Qinfeng Zhu,
• Beibei Gao,
• Qian Chen,
• Tiantian Luo,
• Guobo Xu and
• Shanggao Liao

Beilstein J. Org. Chem. 2022, 18, 1410–1415, doi:10.3762/bjoc.18.146

• basis of 1D and 2D NMR spectroscopy as well as high-resolution mass spectrometry. The absolute configuration of 1 was established by ECD calculation. Compounds 2 and 3 represent rare examples of naturally occurring 9,9'-bisnorlignans. All the isolated compounds were assayed for their inhibitory effects

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

• , implying that TadA can catalyze the formation of a diterpene hydrocarbon (Supporting Information 1, Figure S1). The crude extract was also subjected to high-performance liquid chromatography–mass spectrometry (HPLC–MS) analysis. It showed that introduction of tadA led to the generation of two products 1

• ionization mass spectrometry (HRESIMS), the molecular formula of 1 was deduced as C20H32, indicating that 1 has five degrees of unsaturation. The 13C NMR spectrum showed that there are four olefinic carbons (δC 153.2, 137.4, 125.1, 118.6) in 1. We thus reasoned that 1 features a tricyclic system

Preparation of an advanced intermediate for the synthesis of leustroducsins and phoslactomycins by heterocycloaddition

• Anaïs Rousseau,
• Guillaume Vincent and
• Cyrille Kouklovsky

Beilstein J. Org. Chem. 2022, 18, 1385–1395, doi:10.3762/bjoc.18.143

• solvent using residual chloroform (7.26 ppm) as an internal reference. 13C NMR spectra were measured at 62.5, 75 or 90 MHz using residual chloroform (77.1 ppm) as an internal reference. High-resolution mass spectrometry (HRMS) analyses were conducted with electro spray ionization (ESI). 6

On drug discovery against infectious diseases and academic medicinal chemistry contributions

• Yves L. Janin

Beilstein J. Org. Chem. 2022, 18, 1355–1378, doi:10.3762/bjoc.18.141

• , parallel/combinatorial synthesis, multicomponent chemistry, metal-catalyzed coupling reactions as well as NMR, preparative/analytical liquid chromatography and mass spectrometry). – An improved understanding of molecular pharmacology along with in vitro or in vivo assays to detect various aspects of drug

Ionic multiresonant thermally activated delayed fluorescence emitters for light emitting electrochemical cells

• Merve Karaman,
• Abhishek Kumar Gupta,
• Subeesh Madayanad Suresh,
• Tomas Matulaitis,
• Lorenzo Mardegan,
• Daniel Tordera,
• Henk J. Bolink,
• Sen Wu,
• Stuart Warriner,
• Ifor D. Samuel and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2022, 18, 1311–1321, doi:10.3762/bjoc.18.136

• synthetic strategy, which itself was synthesized from Br-DiKTa [28] following a Buchwald–Hartwig coupling. Details of the synthesis are found in Supporting Information File 1. The identity and purity of the molecules were verified using a combination of 1H and 13C NMR spectroscopy, high resolution mass

• spectrometry (HRMS) (Figures S1–S24 in Supporting Information File 1), and melting point analysis. We modelled the electron density distribution in DiKTa-OBuIm and DiKTa-DPA-OBuIm using density functional theory (DFT) calculations in the ground state, at the PBE0/6-31G(d,p) level of theory in the gas phase

Thermally activated delayed fluorescence (TADF) emitters: sensing and boosting spin-flipping by aggregation

• Ashish Kumar Mazumdar,
• Gyana Prakash Nanda,
• Nisha Yadav,
• Upasana Deori,
• Upasha Acharyya,
• Bahadur Sk and
• Pachaiyappan Rajamalli

Beilstein J. Org. Chem. 2022, 18, 1177–1187, doi:10.3762/bjoc.18.122

• Supporting Information File 1. Both compounds were further purified by temperature-gradient vacuum sublimation and characterized by 1H and 13C NMR spectroscopy (Figures S9–S12, Supporting Information File 1) as well as high-resolution mass spectrometry. Photophysical studies and DFT calculations The UV–vis

Experimental and theoretical studies on the synthesis of 1,4,5-trisubstituted pyrrolidine-2,3-diones

• Nguyen Tran Nguyen,
• Vo Viet Dai,
• Nguyen Ngoc Tri,
• Luc Van Meervelt,
• Nguyen Tien Trung and
• Wim Dehaen

Beilstein J. Org. Chem. 2022, 18, 1140–1153, doi:10.3762/bjoc.18.118

• structures of the obtained compounds were elucidated by NMR and mass spectrometry. The reaction between 1,5-diphenyl-4-acetyl-3-hydroxy-3-pyrrolin-2-one (4a) and 4-methoxybenzylamine (9a) was chosen to optimize the reaction conditions, such as the reactant ratio and solvent. Heating 2-pyrrolidinone

Facile and diastereoselective arylation of the privileged 1,4-dihydroisoquinolin-3(2H)-one scaffold

• Dmitry Dar’in,
• Grigory Kantin,
• Alexander Bunev and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2022, 18, 1070–1078, doi:10.3762/bjoc.18.109

• spectrum), mass spectrometry and, in the case of compound 10c, by single-crystal X-ray crystallography (Scheme 2). Using compound 10a as the model substrate, we proceeded to screen for suitable reaction conditions that would allow involving this kind of diazo compounds in the TfOH-promoted benzene C

Introducing a new 7-ring fused diindenone-dithieno[3,2-b:2',3'-d]thiophene unit as a promising component for organic semiconductor materials

• Valentin H. K. Fell,
• Joseph Cameron,
• Alexander L. Kanibolotsky,
• Eman J. Hussien and
• Peter J. Skabara

Beilstein J. Org. Chem. 2022, 18, 944–955, doi:10.3762/bjoc.18.94

• refluxed overnight [43]. The result was a dark violet/black material, which was not soluble in common organic solvents, thereby preventing NMR spectroscopy. Also, sublimation failed. However, the mass could be measured with MALDI mass spectrometry, and microanalysis results matched the theoretical values

Morita–Baylis–Hillman reaction of 3-formyl-9H-pyrido[3,4-b]indoles and fluorescence studies of the products

• Nisha Devi and
• Virender Singh

Beilstein J. Org. Chem. 2022, 18, 926–934, doi:10.3762/bjoc.18.92

• transformation than 6e. It is noteworthy here that all the products were purified by column chromatography. A small library of C-3-substituted pyrido[3,4-b]indole derivatives was designed and synthesized which is presented in Figure 4. All the products were characterized using NMR, FTIR and mass spectrometry

Cathodic generation of reactive (phenylthio)difluoromethyl species and its reactions: mechanistic aspects and synthetic applications

• Sadanobu Iwase,
• Shinsuke Inagi and
• Toshio Fuchigami

Beilstein J. Org. Chem. 2022, 18, 872–880, doi:10.3762/bjoc.18.88

• difluorocarbene adduct 5 was detected by high resolution mass spectrometry in addition to products 2, 3, and 4. As already mentioned, SmI2 is a well-known one-electron reducing reagent, and has been used to generate PhSCF2 radicals and perfluoroalkyl radicals from PhSCF2Br and perfluoroalkyl halides, respectively

First series of N-alkylamino peptoid homooligomers: solution phase synthesis and conformational investigation

• Maxime Pypec,
• Laurent Jouffret,
• Claude Taillefumier and
• Olivier Roy

Beilstein J. Org. Chem. 2022, 18, 845–854, doi:10.3762/bjoc.18.85

• ) for compound 2, CCDC deposition number 2167472. Acknowledgements We express our sincere thanks to M. Leremboure and F. Emenegger for mass spectrometry analyses (UCA PARTNER). We also thank H. Billard and J. Colombet, Plateforme CYSTEM – UCA PARTNER (Clermont-Ferrand, FRANCE), for their technical

Synthesis and HDAC inhibitory activity of pyrimidine-based hydroxamic acids

• Virginija Jakubkiene,
• Gabrielius Ernis Valiulis,
• Markus Schweipert,
• Asta Zubriene,
• Daumantas Matulis,
• Franz-Josef Meyer-Almes and
• Sigitas Tumkevicius

Beilstein J. Org. Chem. 2022, 18, 837–844, doi:10.3762/bjoc.18.84

• chromatography was performed using silica gel 60 (0.040–0.063 mm) (Merck). NMR spectra were recorded on a Bruker Ascend 400 spectrometer (400 MHz and 100 MHz for 1H and 13C, respectively). 1H NMR and 13C NMR were referenced to residual solvent peaks. High-resolution mass spectrometry (HRMS) analyses were carried

Identification of the new prenyltransferase Ubi-297 from marine bacteria and elucidation of its substrate specificity

• Jamshid Amiri Moghaddam,
• Huijuan Guo,
• Karsten Willing,
• Thomas Wichard and
• Christine Beemelmanns

Beilstein J. Org. Chem. 2022, 18, 722–731, doi:10.3762/bjoc.18.72

• obtained after washing and ultracentrifugation. Substrate specificity of UbiA-297 Based on our in silico analysis and previous mass-spectrometry-guided metabolomic analysis of marine Flavobacteria and members of the genus Saccharomonospora [29][30], we anticipated hydroxylated aromatic or even quinoline

• presence of Mg2+ as co-factor. Product formation was monitored after 2 h using high-resolution tandem mass spectrometry (HRMS/MS). Membrane proteins obtained from E. coli BL21 cultures harboring the empty expression pET28 plasmid were used as negative control (Figure S3 in Supporting Information File 1

Cholyl 1,3,4-oxadiazole hybrid compounds: design, synthesis and antimicrobial assessment

• Anas J. Rasras,
• Mohamed El-Naggar,
• Nesreen A. Safwat and
• Raed A. Al-Qawasmeh

Beilstein J. Org. Chem. 2022, 18, 631–638, doi:10.3762/bjoc.18.63

• were obtained from piperidine and pyrrolidine, respectively, as secondary cyclic amine component (Figure 2). The structures of the newly synthesized compounds were confirmed on the basis of their spectral data in particular nuclear magnetic resonance (NMR) and mass spectrometry (MS) techniques. The 1H

Synthesis of a new water-soluble hexacarboxylated tribenzotriquinacene derivative and its competitive host–guest interaction for drug delivery

• Man-Ping Li,
• Nan Yang and
• Wen-Rong Xu

Beilstein J. Org. Chem. 2022, 18, 539–548, doi:10.3762/bjoc.18.56

• competitive guest to control the release of MV and DOX. The structures of the target molecule TBTQ-CB6 and its precursors were characterized by NMR spectroscopy and mass spectrometry. The host–guest chemistry of TBTQ-CB6MV, TBTQ-CB6DOX and TBTQ-CB6SM was investigated by NMR spectroscopy and fluorescence

• synthesized compounds were fully characterized by 1H and 13C NMR spectroscopy and mass spectrometry (see Supporting Information File 1) and the data were found to be consistent with the proposed structures. Host–guest complexation of TBTQ-CB6 with dimethyl viologen (MV). The host–guest complexation between

• host–guest interactions. The target compound TBTQ-CB6 was characterized in detail by NMR spectroscopy and mass spectrometry. The host–guest complexes of TBTQ-CB6 with MV, DOX, and the overexpressed molecule spermine (SM) found within cancer cells are formed in a 1:1 stoichiometry in all cases and with