Non-peptide compounds from Kronopolites svenhedini (Verhoeff) and their antitumor and iNOS inhibitory activities

• Yuan-Nan Yuan,
• Jin-Qiang Li,
• Hong-Bin Fang,
• Shao-Jun Xing,
• Yong-Ming Yan and
• Yong-Xian Cheng

Beilstein J. Org. Chem. 2023, 19, 789–799, doi:10.3762/bjoc.19.59

• identification Compound 1, a yellow gum, possesses the molecular formula C14H18O4 (six degrees of unsaturation), as deduced from its HRESIMS [M + H]+ ion peak at m/z 251.1274 (calcd for C14H19O4, 251.1278). The 1H NMR data (Table 1 and Figure S1 in Supporting Information File 1) display one aromatic proton [δH

• experimental and ECD spectra (Figure 3 and Figure S26 in Supporting Information File 1). Consequently, the structure of 4 is defined and named 5-O-methyldaphnegiralin C1. Compound 7, a light yellow gum, has the molecular formula C16H28O3 (three degrees of unsaturation) as determined by its HRESIMS [M + H]+ ion

• at C-3 remains undetermined due to its long carbon chain. As a consequence, the structure of compound 7, named kronoponoid A, was determined to be as showed in Figure 1. Compound 8, a light yellow gum, possesses the molecular formula C17H30O3 (three degrees of unsaturation) deduced from its HRESIMS

Synthesis, structure, and properties of switchable cross-conjugated 1,4-diaryl-1,3-butadiynes based on 1,8-bis(dimethylamino)naphthalene

• Semyon V. Tsybulin,
• Ekaterina A. Filatova,
• Alexander F. Pozharskii,
• Valery A. Ozeryanskii and
• Anna V. Gulevskaya

Beilstein J. Org. Chem. 2023, 19, 674–686, doi:10.3762/bjoc.19.49

• nitro group. There are two types of independent non-equivalent dications, marked in blue and green, and two types of BF4− anions, marked in red and yellow, in the crystal structure of salt 11c (Figure S68 in Supporting Information File 1). Monomer fragments in both are identical (Table 2, Figure 5). The

• -trifluoromethylphenyl rings. By the way, the qr parameters calculated for two independent molecules of 11c were 0.008 and 0.009, which is slightly less than in the case of compounds 5. As for the crystal packing of 11c, BF4− anions of two types (“red” and “yellow”) interact with cations in different ways. The “red

• ” anion hangs over the cationic centers of both independent molecules, which are almost perpendicular to each other, while the “yellow” one participates mainly in the coordination with the hydrogen atoms of the NMe2 groups. Such a distribution of counterions apparently ensures mutually perpendicular

pH-Responsive fluorescent supramolecular nanoparticles based on tetraphenylethylene-labelled chitosan and a six-fold carboxylated tribenzotriquinacene

• Nan Yang,
• Yi-Yan Zhu,
• Wei-Xiu Lin,
• Yi-Long Lu and
• Wen-Rong Xu

Beilstein J. Org. Chem. 2023, 19, 635–645, doi:10.3762/bjoc.19.45

• powders of CS-TPE exhibit a pale-yellow appearance under normal daylight conditions and emit intense green-blue light when exposed to UV irradiation (365 nm). This phenomenon differs greatly from the fluorescence properties of conventional ACQ fluorophores, which are typically nonfluorescent under UV

• the mixture was heated at 70 °C with stirring for 6–10 h. The resulting mixture was then allowed to stand overnight, and the solvent was removed under reduced pressure to obtain the crude Schiff base as a pale-yellow solid. Without further purification, the Schiff base was dispersed in methanol (60 mL

• give CS-TPE as a pale-yellow solid. The CS-TPE obtained with feed ratios (Rf) of 2, 10, and 20 mol % were denominated CS-TPE-2%, CS-TPE-10%, and CS-TPE-20%, respectively. The labelling degree (DL) of CS-TPE was calculated by Equation 1 based on the 1H NMR data. Preparation of TBTQ-C6/CS-TPE

Phenanthridine–pyrene conjugates as fluorescent probes for DNA/RNA and an inactive mutant of dipeptidyl peptidase enzyme

• Josipa Matić,
• Tana Tandarić,
• Marijana Radić Stojković,
• Filip Šupljika,
• Zrinka Karačić,
• Ana Tomašić Paić,
• Lucija Horvat,
• Robert Vianello and
• Lidija-Marija Tumir

Beilstein J. Org. Chem. 2023, 19, 550–565, doi:10.3762/bjoc.19.40

• trifluoroacetate salt of the deprotected amino acid was obtained as yellow oil after evaporation of the solvent. The deprotected compound was then dissolved in anhydrous acetonitrile (3 mL) and appropriate pyrenecarboxylic acid, HBTU, HOBt and Et3N were added. The reaction was stirred at room temperature for 20

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

• dialysis against water overnight, followed by lyophilization. The resulting polymer was obtained as a slightly yellow powder. The synthesis of 2-ethyl-3-methyloxazolinium triflate was carried out as follows: 30 mL of dry diethyl ether were placed in a dry round-bottomed flask and methyl

• rapidly turned yellow, which is another sign of undesired side reactions. Besides, 1H NMR spectra of the obtained polymers during the polymerization process (Figure S1 in Supporting Information File 1) demonstrate the appearance of new signals at 1.65 ppm (box a), 2.84 ppm (box b), 3.20 (box c), 3.82 ppm

An accelerated Rauhut–Currier dimerization enabled the synthesis of (±)-incarvilleatone and anticancer studies

• Tharun K. Kotammagari,
• Sweta Misra,
• Sayantan Paul,
• Sunita Kunte,
• Rajesh G. Gonnade,
• Manas K. Santra and
• Asish K. Bhattacharya

Beilstein J. Org. Chem. 2023, 19, 204–211, doi:10.3762/bjoc.19.19

• temperature resulted in the formation of heterodimerized product (±)-4 in 38% yield as a pale-yellow solid (Scheme 3, method A). The yield of this reaction could not be improved even by prolonging the reaction time (up to 24 h). However, when we treated (±)-rengyolone (3) with 1.0 M TBAF (2 equiv) in THF at

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

• chromatography; enantioselective synthesis; GC/MS; semiochemicals; Introduction Hyperolius cinnamomeoventris (Figure 1) is one of the largest species of reed frogs (Hyperoliidae), which are commonly found in Africa, south of the Sahara. Males of the Hyperoliidae possess a characteristic yellow gular patch on

• their vocal sac that also serves as a gland which emits volatile organic compounds during calling [1]. These courtship calls are trimodal, consisting of calls, yellow flashing signals, and volatile chemicals released from the gland [2]. The semiochemical signal, the glandular secretion, seems to be used

• mass spectrometric and gas chromatographic data to be acquired, clarifying the identity and stereochemistry of several cadinols. Calling male Hyperolius cinnamomeoventris with exposed vocal sac carrying the yellow gular gland. Figure 1 was reprinted from [2], I. Starnberger et al., “Take time to smell

Synthesis and characterisation of new antimalarial fluorinated triazolopyrazine compounds

• Kah Yean Lum,
• Jonathan M. White,
• Daniel J. G. Johnson,
• Vicky M. Avery and
• Rohan A. Davis

Beilstein J. Org. Chem. 2023, 19, 107–114, doi:10.3762/bjoc.19.11

• = 2.7 Hz, C-13); LRESIMS m/z: 451 [M + H]+, 473 [M + Na]+, 923 [2M + Na]+; HRESIMS (m/z): [M + H]+ calcd for C21H16F5N4O2, 451.1188; found, 451.1195. 8-(1,1-Difluoroethyl)-3-(4-(difluoromethoxy)phenyl)-5-phenethoxy-[1,2,4]triazolo[4,3-a]pyrazine (11). Yellow amorphous solid (23 mg, 51%); UV (MeOH) λmax

• ]pyrazine (14). Yellow amorphous solid (18 mg, 44%); UV (MeOH) λmax (log ε): 243 (4.23), 286 (3.81), 317 (3.80) nm; 1H NMR (800 MHz, CDCl3) δH 2.26 (t, J = 18.9 Hz, 3H, H-25), 2.95 (t, J = 6.5 Hz, 2H, H-17), 4.49 (t, J = 6.5 Hz, 2H, H-16), 6.88 (m, 2H, H-19, H-23), 7.23 (m, 1H, H-21), 7.24 (m, 2H, H-20, H

• ), 146.4 (C-3); LRESIMS m/z: 410 [M + H]+, 432 [M + Na]+; HRESIMS (m/z): [M + H]+ calcd for C21H15F3N5O, 410.1223; found, 410.1221. 4-(8-(1,1-Difluoroethyl)-5-phenethoxy-[1,2,4]triazolo[4,3-a]pyrazin-3-yl)benzonitrile (17). Yellow amorphous solid (23 mg, 56%); UV (MeOH) λmax (log ε): 226 (4.41), 250 (4.33

Preparation of β-cyclodextrin/polysaccharide foams using saponin

• Max Petitjean and
• José Ramón Isasi

Beilstein J. Org. Chem. 2023, 19, 78–88, doi:10.3762/bjoc.19.7

• same trends are observed for all the polysaccharide types (Figure 7). Those matrices with cyclodextrin (yellow bars in Figure 7) absorbed better all the phenolic compounds tested. In addition, the incorporation of saponin does not produce a higher sorption capacity except for the XG matrices. In these

• -cyclodextrin/polysaccharides (blue curves for chitosan, red for locust bean gum, green for xanthan gum) with saponin (yellow curves correspond to cyclodextrin matrices, without polysaccharide). Sorption of phenols (V, vanillin; Ph, phenol; m-c, m-cresol; 4eP, 4-ethylphenol; Eu, eugenol) in β-cyclodextrin

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

• isolated by repeated semi-preparative reversed-phase HPLC with diode array detection (0–400 nm) at retention time of 27.5 min (see Supporting Information File 1, Figures S3–S7). It was obtained as a white amorphous powder which was bright yellow when in solution. The molecular formula of 1 was determined

Navigating and expanding the roadmap of natural product genome mining tools

• Friederike Biermann,
• Sebastian L. Wenski and
• Eric J. N. Helfrich

Beilstein J. Org. Chem. 2022, 18, 1656–1671, doi:10.3762/bjoc.18.178

• yellow, genes in green and motifs in violet. Concepts of algorithms in order of complexity and examples of genome mining tools that employ the respective concept. Examples of peptide NPs, the corresponding BGCs of which were determined through retrobiosynthetic analysis and then experimentally verified

• : polytheonamide A (13) [76], closthioamide (14) [77], and biarylitide YYH (15) [33]. gcBGC prioritization process. The bar represents all identified gene clusters in one organism and is subdivided into primary (green) on the left and secondary metabolism (yellow) on the right. Gene clusters associated with

Simple synthesis of multi-halogenated alkenes from 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane)

• Yukiko Karuo,
• Atsushi Tarui,
• Kazuyuki Sato,
• Kentaro Kawai and
• Masaaki Omote

Beilstein J. Org. Chem. 2022, 18, 1567–1574, doi:10.3762/bjoc.18.167

• concentrated under reduced pressure. The residue was purified by column chromatography (hexane only) to afford 7 in 80% yield (107.2 mg) as a yellow oil. 1H NMR (400 MHz, CDCl3) δ 0.127 and 0.239 (s, 9H), 7.06–7.14 (m, 2H), 7.16–7.22 (m, 1H), 7.32–7.41 (m, 2H); 13C NMR (100 MHz, CDCl3) δ −0.364, −0.259, 85.3

Using UHPLC–MS profiling for the discovery of new sponge-derived metabolites and anthelmintic screening of the NatureBank bromotyrosine library

• Sasha Hayes,
• Aya C. Taki,
• Kah Yean Lum,
• Joseph J. Byrne,
• Merrick G. Ekins,
• Robin B. Gasser and
• Rohan A. Davis

Beilstein J. Org. Chem. 2022, 18, 1544–1552, doi:10.3762/bjoc.18.164

• time. 5-Debromopurealidin H (1) was isolated as a stable yellow film. The LRESIMS of 1 showed 1:1 ion cluster peaks at m/z 382/384 [M + H]+ and 380/382 [M − H]−, indicating the presence of one bromine atom [16]. Furthermore, a molecular formula of C14H17BrN5O3 was assigned following analysis of the 1D

• a further 10 min, all at a flow rate of 9 mL/min. Sixty 1 min fractions were collected from time 0 to 60 min to afford 5-debromopurealidin H (1, 11.1 mg, tR 32–34 min, 0.111% dry wt), and the known alkaloid ianthesine E (2, 161.2 mg, tR 40–41 min, 1.612% dry wt). 5-Debromopurealidin H (1): Yellow

• for C14H1779BrN5O3, 382.0509). Ianthesine E (2): Yellow film; + 76.3 (c 0.4 in MeOH), lit. + 50.6 (c 0.3 in MeOH) [15]; (+)-LRESIMS m/z 714/716/718/720/722 (1:4:6:4:1) [M + H]+, (−)-LRESIMS m/z 792/794/796/798/800 (1:4:6:4:1) [M − H]−. Preparation of nematode larvae for bioassays Haemonchus

A facile approach to spiro[dihydrofuran-2,3'-oxindoles] via formal [4 + 1] annulation reaction of fused 1H-pyrrole-2,3-diones with diazooxindoles

• Pavel A. Topanov,
• Anna A. Maslivets,
• Maksim V. Dmitriev,
• Irina V. Mashevskaya,
• Yurii V. Shklyaev and
• Andrey N. Maslivets

Beilstein J. Org. Chem. 2022, 18, 1532–1538, doi:10.3762/bjoc.18.162

• the solution being turned from purple to red. The starting FPD 1a is bright violet; thus, the disappearance of the violet color was used as an indicator of the reaction’s completion. Product 3aa was isolated as yellow crystals in 73% yield and characterized by NMR, IR, and mass spectra, and single

New triazole-substituted triterpene derivatives exhibiting anti-RSV activity: synthesis, biological evaluation, and molecular modeling

• Elenilson F. da Silva,
• Krist Helen Antunes Fernandes,
• Denise Diedrich,
• Jessica Gotardi,
• Marcia Silvana Freire Franco,
• Carlos Henrique Tomich de Paula da Silva,
• Ana Paula Duarte de Souza and
• Simone Cristina Baggio Gnoatto

Beilstein J. Org. Chem. 2022, 18, 1524–1531, doi:10.3762/bjoc.18.161

• Figure 3, compound 8 (in yellow sticks) interacted through hydrogen bonds with Arg108 and Tyr421, represented by magenta dots, similar to the interactions observed in the crystallographic complex with IMP and the inhibitor MAD1, in cyan sticks. Moreover, the acetate group (at C-3 position) and nitroaryl

• with compound 8. (B) Viral load quantification by real-time PCR after treatment with compound 8. Superposition of the top-ranked docking solution of compound 8 (carbon atoms in yellow, in stick representation) with the crystallographic poses of IMP and inhibitor MAD1 (color by atoms in stick

Comparison of crystal structure and DFT calculations of triferrocenyl trithiophosphite’s conformance

• Ruslan P. Shekurov,
• Mikhail N. Khrizanforov,
• Ilya A. Bezkishko,
• Tatiana P. Gerasimova,
• Almaz A. Zagidullin,
• Daut R. Islamov and
• Vasili A. Miluykov

Beilstein J. Org. Chem. 2022, 18, 1499–1504, doi:10.3762/bjoc.18.157

• vacuo. The product was extracted with benzene (3 × 30 mL) and after evaporation of the solvent triferrocenyl trithiophosphite (1.34 g, 76%) was obtained as a yellow powder. Single crystals suitable for X-ray diffraction were obtained by dissolving the compound in a mixture of benzene/hexane 1:1 and

• atoms – orange, S atoms – yellow. Quantum chemically optimized conformations of the (PhS)3P molecule and their relative energies (kcal/mol). Calculated relative energies and dihedral angles Fc(C)–S–P=X (°) (X = LEP, O, S) of four possible conformers of (FcS)3P, (FcS)3PO, and (FcS)3PS. Supporting

Naphthalimide-phenothiazine dyads: effect of conformational flexibility and matching of the energy of the charge-transfer state and the localized triplet excited state on the thermally activated delayed fluorescence

• Kaiyue Ye,
• Liyuan Cao,
• Davita M. E. van Raamsdonk,
• Zhijia Wang,
• Jianzhang Zhao,
• Daniel Escudero and
• Denis Jacquemin

Beilstein J. Org. Chem. 2022, 18, 1435–1453, doi:10.3762/bjoc.18.149

• chromatography (silica gel, DCM/MeOH 50:1, v:v). NI-PTZ-O was obtained as yellow solid. Yield: 180 mg (87.2%). Mp 176.2–177.2 °C; 1H NMR (CDCl3, 400 MHz) δ 0.88–0.98 (m, 6H), 1.27–1.43 (m, 8H), 1.95–2.01 (m, 1H), 4.11–4.22 (m, 2H), 6.67 (d, J = 8.26 Hz, 2H), 7.29 (d, J = 7.38 Hz, 2H), 7.38–7.42 (m, 2H), 7.88

• anhydrous Na2SO4 and the solvent was evaporated under reduced pressure. The crude product was purified by column chromatography (silica gel, DCM/PE 6:1, v:v). The product NI-Ph-PTZ was obtained as yellow solid. Yield: 40 mg (62.4%). Mp 126.7–128.3 °C; 1H NMR (CDCl3, 400 MHz) δ 0.94–0.97 (m, 6H), 1.33–1.42

• over anhydrous Na2SO4 and the solvent was evaporated under reduced pressure. The crude product was purified by column chromatography (silica gel, DCM/PE 1:5, v:v). The product NI-PhMe2-PTZ was obtained as yellow solid. Yield: 50 mg (28.3%). Mp 121.2–122.4 °C; 1H NMR (CDCl3, 400 MHz) δ 0.89–0.97 (m, 6H

Mechanochemical synthesis of unsymmetrical salens for the preparation of Co–salen complexes and their evaluation as catalysts for the synthesis of α-aryloxy alcohols via asymmetric phenolic kinetic resolution of terminal epoxides

• Shengli Zuo,
• Shuxiang Zheng,
• Jianjun Liu and
• Ang Zuo

Beilstein J. Org. Chem. 2022, 18, 1416–1423, doi:10.3762/bjoc.18.147

• outlined in Scheme 3. Reaction conditions were described previously [17][46]. For reactions using Zn and Cu, Zn(OAc)2·2H2O or Cu(OAc)2·H2O in methanol was dropwise added to 1a, b, or d in ethanol under nitrogen gas. The reaction mixture was refluxed for 4 hours and a light yellow or dark green solid was

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

• yellow amorphous powder. The negative HRESIMS [M − H]− at m/z 371.1133 (calcd for 371.1136) suggested its molecular formula to be C20H20O7, corresponding to 11 degrees of unsaturation. The IR spectrum showed absorption bands characteristic of hydroxy group (3450 cm−1), carbonyl (1765 cm−1), and aromatic

• compounds Compound 1: pale yellow amorphous powder, 27.81 (c 0.32, MeOH); IR (KBr) νmax: 3540, 1764, 1515, 1445, 1247, 1035 cm−1; ECD (c 2.2 × 10−4 M, MeOH) λmax (Δε) 204 (+4.36), 231 (+1.79) nm; 1H and 13C NMR data, see Table 1; HRESIMS (m/z): [M − H]− calcd for C20H19O7, 371.1136; found, 371.1133

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

• (MgSO4), filtered and concentred under reduced pressure to give a brown oil. Purification by column chromatography (25% AcOEt/cyclohexane) gave the enol phosphate 17 as a yellow oil (200 mg, 26%). Rf: 0.47 (30% AcOEt/cyclohexane); 1H NMR (360 MHz, CDCl3) δ 6.15 (dd, J = 17.3, 10.8 Hz, 1H), 5.47 (d, J

• dichloromethane (3 × 74 mL). The combined organic layers were dried (MgSO4), filtered and concentred under reduced pressure. Purification of the crude product by column chromatography (30% AcOEt/cyclohexane) gave the cycloadduct 10b as a yellow oil (404 mg, 73%). Rf: 0.42 (30% AcOEt/cyclohexane); 1H NMR (360 MHz

• reduced pressurre, the residue taken up with dichloromethane (10 mL) and filtered, washing with dichloromethane (3 × 5 mL). The filtrate was concentred under reduced pressure to give a yellow oil (300 mg) consisting in a mixture of the ketone 11b and the over-reduced alcohol. This mixture was carried into

Computational model predicts protein binding sites of a luminescent ligand equipped with guanidiniocarbonyl-pyrrole groups

• Neda Rafieiolhosseini,
• Matthias Killa,
• Thorben Neumann,
• Niklas Tötsch,
• Jean-Noël Grad,
• Alexander Höing,
• Thies Dirksmeyer,
• Jochen Niemeyer,
• Christian Ottmann,
• Shirley K. Knauer,
• Michael Giese,
• Jens Voskuhl and
• Daniel Hoffmann

Beilstein J. Org. Chem. 2022, 18, 1322–1331, doi:10.3762/bjoc.18.137

• two binding grooves for protein ligands, e.g., the C-Raf peptides (yellow). The structure is based on PDB entry 4IHL [20]. Workflow of the computational approach used in this study. The protein structure and the structure of the ligand fragments are the required inputs. Charges and radii are assigned

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

• plots and energies for the two lowest-lying singlet and triplet excited states for DiKTa-OMe and DiKTa-DPA-OMe calculated at SCS-CC2/cc-pVDZ in the gas phase (isovalue = 0.001). The blue color represents an area of decreased electron density, and yellow represents an increased electron density between

Enantioselective total synthesis of putative dihydrorosefuran, a monoterpene with an unique 2,5-dihydrofuran structure

• Irene Torres-García,
• Josefa L. López-Martínez,
• Rocío López-Domene,
• Manuel Muñoz-Dorado,
• Ignacio Rodríguez-García and
• Miriam Álvarez-Corral

Beilstein J. Org. Chem. 2022, 18, 1264–1269, doi:10.3762/bjoc.18.132

• -methylhepta-5,6-dienoate (3, 225 mg, 81%) isolated as light yellow oil. IR (ATR) ν (cm−1): 3434, 2972, 2928, 1958, 1723, 1436, 1374, 1172, 1028, 925, 853; 1H NMR (300 MHz, CDCl3) δ 4.77 (dq, J = 2.3, 3.2 Hz, 2H), 4.12 (q, J = 7.1 Hz, 2H), 4.05 (m, 1H), 2.42 (t, J = 7.2 Hz, 2H), 2.18 (s, 1H), 2.04–1.77 (m, 2H

A Streptomyces P450 enzyme dimerizes isoflavones from plants

• Run-Zhou Liu,
• Shanchong Chen and
• Lihan Zhang

Beilstein J. Org. Chem. 2022, 18, 1107–1115, doi:10.3762/bjoc.18.113

• using organic solvent (CHCl3/MeOH 1:1, v/v, 20 L in total). After removing the solvent in vacuo, the crude extract was redissolved in methanol and separated by Sephdex LH-20 (GE healthcare) column chromatography using methanol as eluent. The yellow band at the elution tail on the LH-20 column (Figure S2

Scope of tetrazolo[1,5-a]quinoxalines in CuAAC reactions for the synthesis of triazoloquinoxalines, imidazoloquinoxalines, and rhenium complexes thereof

• Laura Holzhauer,
• Chloé Liagre,
• Olaf Fuhr,
• Nicole Jung and
• Stefan Bräse

Beilstein J. Org. Chem. 2022, 18, 1088–1099, doi:10.3762/bjoc.18.111

• complexation of the 3-nitrogen of the triazole ring and the nitrogen of the amine side chain. The complex has a yellow color in contrast to the red complexes 27a–d. Using TIQ ligand 25b for a complexation attempt with Re(CO)5Br, an orange complex (30) was successfully isolated in 79% yield. Single crystals