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

Synthesis, optical and electrochemical properties of (D–π)₂-type and (D–π)₂Ph-type fluorescent dyes

• Kosuke Takemura,
• Kazuki Ohira,
• Taiki Higashino,
• Keiichi Imato and
• Yousuke Ooyama

Beilstein J. Org. Chem. 2022, 18, 1047–1054, doi:10.3762/bjoc.18.106

• and OTT-2 are nearly-colorless and greenish-yellow, and show blue and green fluorescent colors, respectively. The photoabsorption spectra demonstrate that the photoabsorption maximum wavelength (λmax, abs = 424 nm) of OTT-2 occurs at a by 29 nm longer wavelength than that (λmax, abs = 395 nm) of OTK-2

• fluorescence spectroscopy for the solids (Figure 1c,d). As shown in insets of Figure 1c,d, in the solid state, the colors are yellowish orange for OTK-2 and orange for OTT-2, and the fluorescent colors are greenish yellow for OTK-2 and yellow for OTT-2. The photoabsorption bands of OTK-2 and OTT-2 in the solid

• , and then, the solution was extracted with dichloromethane. The dichloromethane extract was dried over anhydrous MgSO4, filtrated, and concentrated. The residue was chromatographed on silica gel (ethyl acetate/hexane 1:4 ) to give OTK-2 (19 mg, yield 27%) and OTT-2 (9 mg, yield 14%) as a light yellow

Isolation and biosynthesis of daturamycins from Streptomyces sp. KIB-H1544

• Yin Chen,
• Jinqiu Ren,
• Ruimin Yang,
• Jie Li,
• Sheng-Xiong Huang and
• Yijun Yan

Beilstein J. Org. Chem. 2022, 18, 1009–1016, doi:10.3762/bjoc.18.101

• DatA, which catalyzes the Claisen–Dieckmann condensation of phenylpyruvic acid (7) to generate the key intermediate polyporic acid (8). Finally, we proposed a biosynthetic pathway for daturamycins. Results and Discussion Daturamycin A (1), a yellow powder, possessed a molecular formula of C19H16O5 with

• ): pale yellow solid; IR (KBr) νmax: 3468, 3287, 1731, 1702, 1631, 1398 and 1202 cm−1; UV (MeOH) λmax (log ε): 314 (0.48), 217 (0.28), 202 (0.48); 1H and 13C NMR, see Table 1; HRMS–ESI (m/z): [M + Na]+ calcd for C19H16O5Na+, 347.0890; found, 347.0893. Daturamycin B (2): white powder; 1H and 13C NMR, see

Molecular diversity of the base-promoted reaction of phenacylmalononitriles with dialkyl but-2-ynedioates

• Hui Zheng,
• Ying Han,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2022, 18, 991–998, doi:10.3762/bjoc.18.99

• -hydroxy-4-(4-methoxyphenyl)cyclopent-2-ene-1-carboxamido)-5-(4-methoxyphenyl)cyclopenta-2,4-diene-1,2-dicarboxylate (4a): yellow solid, 62%; mp 182–184 °C; 1H NMR (400 MHz, CDCl3) δ 8.92 (s, 1H, NH), 7.46 (d, J = 8.4 Hz, 2H, ArH), 7.34 (d, J = 8.4 Hz, 2H, ArH), 6.90 (s, 1H, CH), 6.88–6.84 (m, 4H, ArH

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

• -bromobenzoate) (27), which is a yellow solid (Scheme 2). This step was found to be problematic. Purification was difficult, moreover, the batch-to-batch yield strongly fluctuated and was generally low. Intermediate 27 degraded during column chromatography, but this could be prevented by adding a small amount of

Post-synthesis from Lewis acid–base interaction: an alternative way to generate light and harvest triplet excitons

• Hengjia Liu and
• Guohua Xie

Beilstein J. Org. Chem. 2022, 18, 825–836, doi:10.3762/bjoc.18.83

• HCl, TFA, and BBr3 as dopants which were respectively added to the donor–acceptor–donor (D–A–D) molecule 2,5-bis((N,N-diphenylamino)phenyl)thiazolothiazole (compound 2 in Figure 2) containing thiazolothiazole units. As shown in Figure 3b, four different colors ranged from green, yellow, red and NIR

• colors of green (524 nm), yellow (576 nm), red (640 nm), and NIR (739 nm) (Figure 3b) [27]. The stronger Lewis acidity resulted in a stronger emission and bathochromic shift when comparing the effects of BCF and B(C6H5)3 on the optoelectronic properties of the organic UV fluorescent material 35DCzPPy (14

Thiophene/selenophene-based S-shaped double helicenes: regioselective synthesis and structures

• Mengjie Wang,
• Lanping Dang,
• Wan Xu,
• Zhiying Ma,
• Liuliu Shao,
• Guangxia Wang,
• Chunli Li and
• Hua Wang

Beilstein J. Org. Chem. 2022, 18, 809–817, doi:10.3762/bjoc.18.81

• ), and then dried over MgSO4. The residue was purified by column chromatography (eluent: hexane/CH2Cl2 3:1 (v/v) and recrystallized from CHCl3/CH3OH to yield 5a (20.9 mg, 46%) as a yellow solid; mp > 300 °C; 1H NMR (400 MHz, CDCl3) δ (ppm) 7.58 (s, 1H), 7.45 (s, 2H), 7.41–7.36 (m, 3H), 7.34 (s, 2H), 7.31

• ); HRMS-MALDI (m/z): [M]+ calcd for C32H30S6Si2, 662.0216; found, 662.0205. 1,3-Bis(2-(5-(trimethylsilyl)diselenopheno[2,3-b:3',2'-d]thiophen-2-yl)vinyl)benzene (5b) was synthesized according to the procedure described for compound 5a. 5b: yellow solid in yield of 64% (46.2 mg); mp > 300 °C; 1H NMR (300

• . Mixture of cis and trans isomers 5c: yellow solid in yield of 50% (24.4 mg); mp > 300 °C; 1H NMR (400 MHz, CDCl3) δ (ppm): 7.76 (s, trans-), 7.73 (s, cis- and trans-), 7.72 (s, cis- and trans-), 7.57 (s, cis- and trans-), 7.56 (s, trans-), 7.49–7.33 (m, trans-, cis- and trans-), 7.30 (d, J = 16.0 Hz, cis

Copper-catalyzed multicomponent reactions for the efficient synthesis of diverse spirotetrahydrocarbazoles

• Shao-Cong Zhan,
• Ren-Jie Fang,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2022, 18, 796–808, doi:10.3762/bjoc.18.80

• ethyl acetate and light petroleum (v/v = 1:3–1:6) as eluent to give pure products 3a–c. 1',3'-Dimethyl-2,4-di-p-tolyl-2'H-spiro[carbazole-3,5'-pyrimidine]-2',4',6'(1'H,3'H)-trione (3a): Yellow solid, 75%, mp 190–192 °C; 1H NMR (400 MHz, CDCl3) δ 7.59 (d, J = 7.6 Hz, 1H, ArH), 7.35–7.30 (m, 4H, ArH

Structural basis for endoperoxide-forming oxygenases

• Takahiro Mori and
• Ikuro Abe

Beilstein J. Org. Chem. 2022, 18, 707–721, doi:10.3762/bjoc.18.71

• -containing natural products. Structures of COXs [52][53]. (A) The overall structure of ovine COX-1. (B and C) Comparison of the cyclooxygenase sites of (B) COX-1 and (C) COX-2 in complex with AA. Yellow dashed lines show hydrogen bond interactions. The blue dashed line shows the distance between Tyr385 and

• C13 of AA. Structure of FtmOx1 [71]. (A) The FtmOx1 binary structure in complex with 2OG. (B and C) Comparison of the active site architectures between (B) the binary structure and (C) the ternary structure. Blue dashed lines show the distances between atoms and yellow dashed lines represent hydrogen

• site of NvfI in complex with asnovolin A. Blue dashed lines show the distances between atoms and yellow dashed lines represent hydrogen bond interactions. Iron atoms are depicted by orange spheres. Reactions of COXs. Proposed reaction mechanisms of COXs [24]. General reaction mechanism of Fe/2OG

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

• was collected by suction filtration, washed, and dried to obtain compound 2 as a yellow solid (3.76 g, 73%). Mp 104.8–106.6 °C; 1H NMR (400 MHz, DMSO-d6, 25 °C) δ 8.18 (s, 6H), 7.36 (s, 6H), 5.36 (s, 12H), 5.21, 5.17 (ABq, J = 12.4 Hz, 12H), 4.21 (s, 3H), 4.15 (q, J = 7.1 Hz, 12H), 1.58 (s, 3H), 1.19

Sesquiterpenes from the soil-derived fungus Trichoderma citrinoviride PSU-SPSF346

• Wiriya Yaosanit,
• Vatcharin Rukachaisirikul,
• Souwalak Phongpaichit,
• Sita Preedanon and
• Jariya Sakayaroj

Beilstein J. Org. Chem. 2022, 18, 479–485, doi:10.3762/bjoc.18.50

• isolation The crude broth ethyl acetate (BE, 16.5 g) and the mycelial ethyl acetate (CE, 2.6 g) extracts were obtained as a dark brown gum and yellow-brown gum, respectively, using the same procedure as previously described [15]. The broth extract was separated by CC over Sephadex LH-20 using a mixture of

Tetraphenylethylene-embedded pillar[5]arene-based orthogonal self-assembly for efficient photocatalysis in water

• Zhihang Bai,
• Krishnasamy Velmurugan,
• Xueqi Tian,
• Minzan Zuo,
• Kaiya Wang and
• Xiao-Yu Hu

Beilstein J. Org. Chem. 2022, 18, 429–437, doi:10.3762/bjoc.18.45

• indicating an efficient energy transfer is taking place. This was further supported by the observation, that upon loading of EsY into the m-TPEWP5G assembly, the color of the donor solution changed from sky blue to greenish-yellow under UV light. At a 2:1 donor/acceptor molar ratio, a maximum FRET efficiency

Menadione: a platform and a target to valuable compounds synthesis

• Acácio S. de Souza,
• Ruan Carlos B. Ribeiro,
• Dora C. S. Costa,
• Fernanda P. Pauli,
• David R. Pinho,
• Matheus G. de Moraes,
• Fernando de C. da Silva,
• Luana da S. M. Forezi and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 381–419, doi:10.3762/bjoc.18.43

• (Scheme 19) [47]. The reaction was carried out in a separatory funnel to which was added menadione (10), sodium hydrosulfite, and water [47]. The mixture was shaken for a few minutes until the solution passed through a brown phase and became yellow. Despite of being an old method, it is very efficient and

Four bioactive new steroids from the soft coral Lobophytum pauciflorum collected in South China Sea

• Di Zhang,
• Zhe Wang,
• Xiao Han,
• Xiao-Lei Li,
• Zhong-Yu Lu,
• Bei-Bei Dou,
• Wen-Ze Zhang,
• Xu-Li Tang,
• Ping-Lin Li and
• Guo-Qiang Li

Beilstein J. Org. Chem. 2022, 18, 374–380, doi:10.3762/bjoc.18.42

• of 3 was established. Compound 4 was obtained as a yellow powder. Based on the HRESIMS data (m/z 427.3569 [M + H]+), the molecular formula was determined to be C29H46O2, 14 mass units less than compound 5 [6]. By comparing the NMR data (Table 1) of 4 and 5, it is obvious that they possess the same

Unexpected chiral vicinal tetrasubstituted diamines via borylcopper-mediated homocoupling of isatin imines

• Marco Manenti,
• Leonardo Lo Presti,
• Giorgio Molteni and
• Alessandra Silvani

Beilstein J. Org. Chem. 2022, 18, 303–308, doi:10.3762/bjoc.18.34

• also shown. Thermal ellipsoids at rt were drawn at the 50% probability level. Atoms are represented with the usual colour code (C: black; N: blue; O: red; S: yellow; H: white). Substrate scope of the borylcopper-mediated homocoupling of oxindole-based N-tert-butanesulfinyl imines 1 (isolated yields in