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

Glycosylated coumarins, flavonoids, lignans and phenylpropanoids from Wikstroemia nutans and their biological activities

• Meifang Wu,
• Xiangdong Su,
• Yichuang Wu,
• Yuanjing Luo,
• Ying Guo and
• Yongbo Xue

Beilstein J. Org. Chem. 2022, 18, 200–207, doi:10.3762/bjoc.18.23

• compounds Compound 1: Pale yellow powder; [α]D25 –38.05 (c 0.1, MeOH); UV (MeOH) λmax nm (log ε) 290 (0.35), 324 (0.32); IR νmax: 3266, 2925, 1739, 1701, 1624, 1457, 1261, 1020, 802, 611, 405 cm–1; 1H, 13C NMR data, see Table 1; ESIMS (positive ion mode): (m/z) 617 [M + H]+; HRESIMS (positive ion mode): (m

1,2-Naphthoquinone-4-sulfonic acid salts in organic synthesis

• Ruan Carlos B. Ribeiro,
• Patricia G. Ferreira,
• Amanda de A. Borges,
• Luana da S. M. Forezi,
• Fernando de Carvalho da Silva and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 53–69, doi:10.3762/bjoc.18.5

• product mixture (Scheme 3B), mainly due to a tautomeric equilibrium (Scheme 3C) [41]. Hartke and Lohmann [70] studied the reaction of β-NQS with secondary aliphatic amines in detail and observed that the 4-amino-1,2-naphthoquinone 21 products are yellow. However, reactions with primary aliphatic amines

Unsaturated fatty acids and a prenylated tryptophan derivative from a rare actinomycete of the genus Couchioplanes

• Shun Saito,
• Kanji Indo,
• Naoya Oku,
• Hisayuki Komaki,
• Masashi Kawasaki and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2021, 17, 2939–2949, doi:10.3762/bjoc.17.203

• mg, tR = 32.1 min). (2E,4E)-2,4-Dimethyl-2,4-octadienoic acid (1): yellow oil; UV (MeOH) λmax (log ε) 264 (4.08) nm; IR (ATR) νmax: 2959, 2610, 1679, 1622, 1417, 1269, 1138, 1012, 926 cm–1; 1H and 13C NMR data, see Table 1 and Table 2; HR–ESI–TOFMS (m/z): [M + Na]+ calcd for C10H16NaO2, 191.1043

• ; found, 191.1044. (2E,4E)-2,4,7-Trimethyl-2,4-octadienoic acid (2): yellow oil; UV (MeOH) λmax (log ε) 260 (4.04) nm; IR (ATR) νmax: 2957, 1681, 1622, 1417, 1269, 1137 cm–1; 1H and 13C NMR data, see Table 1 and Table 2; HR–ESI–TOFMS (m/z): [M + Na]+ calcd for C11H18NaO2, 205.1199; found, 205.1202. (R

• )-(−)-Phialomustin B (3): yellow oil; [α]D27 −12 (c 0.035, CHCl3), [α]D22 −76 (c 0.05, MeOH); UV (MeOH) λmax (log ε) 256 (4.19) nm; IR (ATR) νmax: 2958, 2956, 1686, 1620, 1279, 982 cm–1; 1H and 13C NMR data, see Table 1 and Table 2; HR–ESI–TOFMS (m/z): [M + Na]+ calcd for C12H20NaO2, 219.1356; found, 219.1356. (2E

Biological properties and conformational studies of amphiphilic Pd(II) and Ni(II) complexes bearing functionalized aroylaminocarbo-N-thioylpyrrolinate units

• Samet Poyraz,
• Samet Belveren,
• Sabriye Aydınoğlu,
• Mahmut Ulger,
• Abel de Cózar,
• Maria de Gracia Retamosa,
• Jose M. Sansano and
• H. Ali Döndaş

Beilstein J. Org. Chem. 2021, 17, 2812–2821, doi:10.3762/bjoc.17.192

• (2RS,4SR,5RS)-1-(benzoylcarbamothioyl)-2-benzyl-5-(2,4-dichlorophenyl)pyrrolidine-2,4-dicarboxylate}2Pd (L1-Pd): Brownish yellow solid, 99 mg, 78% yield; mp 187–189 °C (MeOH, decomp.); 1H NMR (400 MHz) δ 8.18–8.15 (m, 6H, minor and major), 8.01–7.94 (m, 4H, minor and major), 7.54–7.14 (m, 16H, minor

• ): Brownish yellow solid, 112 mg, 89% yield; mp 253–255 °C (MeOH, decomp.); 1H NMR (400 MHz) δ 8.18–8.15 (m, 4H, minor and major), 7.79 (d, J = 8.6 Hz, 1H, minor), 7.72 (d, J = 8.6 Hz, 1H, major), 7.51–7.29 (m, 12H, minor and major), 7.22–7.13 (m, 4H, minor and major), 6.47 (dd, J = 8.6 Hz, 2.4 Hz, 1H, minor

• )pyrrolidine-2,4-dicarboxylate}2Pd (L3-Pd): Brownish yellow solid, 100 mg, 78% yield; mp 217–219 °C (MeOH, decomp.). 1H NMR (400 MHz) δ 8.26 (d, J = 1.9 Hz, 2H), 8.21–8.15 (m, 4H,), 7.63 (d, J = 7.9 Hz, 2H), 7.52–7.39 (m, 6H), 7.29–7.25 (m, 6H), 7.23–7.18 (m, 4H), 7.15–7.11 (m, 4H), 7.02 (d, J = 2.2 Hz, 2H

Photophysical, photostability, and ROS generation properties of new trifluoromethylated quinoline-phenol Schiff bases

• Inaiá O. Rocha,
• Yuri G. Kappenberg,
• Wilian C. Rosa,
• Clarissa P. Frizzo,
• Nilo Zanatta,
• Marcos A. P. Martins,
• Isadora Tisoco,
• Bernardo A. Iglesias and
• Helio G. Bonacorso

Beilstein J. Org. Chem. 2021, 17, 2799–2811, doi:10.3762/bjoc.17.191

• -Methyl-4-(trifluoromethyl)quinolin-6-yl)imino)methyl)phenol (3aa): Yellow solid, yield 20%; mp 129–132 °C; 1H NMR (400 MHz, CDCl3) δ 12.98 (s, 1H, OH), 8.72 (s, 1H, CH=N), 8.15 (d, J = 8.9 Hz, 1H, H-8), 7.85 (bs, J = 2.1 Hz, 1H, H-5), 7.74 (dd, J = 9.0, 2.3 Hz, 1H, H-7), 7.61 (s, 1H, H-3), 7.48–7.39 (m

• ]+ calcd for C18H14F3N2O, 331.1053; found, 331.1037. (E)-2-(((2-Phenyl-4-(trifluoromethyl)quinolin-6-yl)imino)methyl)phenol (3ba): Yellow solid, yield 90%; mp 183–186 °C; 1H NMR (600 MHz, CDCl3) δ 12.96 (s, 1H, OH), 8.71 (s, 1H, CH=N), 8.27 (d, J = 8.9 Hz, 1H, H-8), 8.20–8.14 (m, 3H, Ph, H-3), 7.87 (bs, 1H

• (565 MHz, CDCl3) δ −61.62 (CF3); FTIR (ATR) ν: 3057 (ν OH), 1625 (ν CH=N), 1029 (ν C-O) cm−1; HRMS–ESI (m/z): [M + Na]+ calcd for C23H15F3N2NaO, 415.1029; found, 415.1007. (E)-2-(((2-(p-Tolyl)-4-(trifluoromethyl)quinolin-6-yl)imino)methyl)phenol (3ca): Yellow solid, yield 81%; mp 210–213 °C; 1H NMR

Adjusting the length of supramolecular polymer bottlebrushes by top-down approaches

• Tobias Klein,
• Franka V. Gruschwitz,
• Maren T. Kuchenbrod,
• Ivo Nischang,
• Stephanie Hoeppener and
• Johannes C. Brendel

Beilstein J. Org. Chem. 2021, 17, 2621–2628, doi:10.3762/bjoc.17.175

• s (blue), 10 s (magenta), 30 s (green), and 50 s (yellow) for BTU (A) and BTP (C). The injection peaks were omitted for clarity. cryoTEM images of BTU (B) and BTP (D) after 30 s of US exposure (c = 1 mg⋅mL−1). Supporting Information Supporting Information File 316: Synthesis, procedures, and

Silica gel and microwave-promoted synthesis of dihydropyrrolizines and tetrahydroindolizines from enaminones

• Robin Klintworth,
• Garreth L. Morgans,
• Stefania M. Scalzullo,
• Charles B. de Koning,
• Willem A. L. van Otterlo and
• Joseph P. Michael

Beilstein J. Org. Chem. 2021, 17, 2543–2552, doi:10.3762/bjoc.17.170

• alkylation of the anion of pyrrolidin-2-one (16) with ethyl bromoacetate to afford the known compound ethyl 2-(2-oxopyrrolidin-1-yl)acetate (17) [31][32][33] in 77% yield. Thionation of 17 with Lawesson’s reagent in toluene at 80 °C gave the thione 18 as a yellow oil (86%). Reaction of 18 with phenacyl

Exfoliated black phosphorous-mediated CuAAC chemistry for organic and macromolecular synthesis under white LED and near-IR irradiation

• Azra Kocaarslan,
• Zafer Eroglu,
• Önder Metin and
• Yusuf Yagci

Beilstein J. Org. Chem. 2021, 17, 2477–2487, doi:10.3762/bjoc.17.164

• polymer are shown in Figure 7. From the TEM images, it can be concluded that the process leads to the formation of BPNs-embedded cross-linked polymers. The darker regions circled with yellow dashed line in Figure 6a were attributed to the BPNs while the other relatively lighter regions were ascribed to

• ]. Product was obtained pale yellow oil, yield 96%. 1H NMR (500 MHz, DMSO-d6) δ 7.43–7.34 (m, 5H, -C6H5), 4.43 (s, 2H, CH2-N3). FTIR: 2108 cm−1. Synthesis of (azidomethyl)anthracene (Az-2) A literature procedure was used [45]. 9-Hydroxymethylanthracene (7.40 mmol, 1 equiv) was added to DCM (50 mL) and cooled

• the reaction was stirred at 50 °C. After 1 h, the reaction mixture was allowed to cool down, diluted with water and extracted with EtOAc. The combined organic phases were washed with brine, dried with anhydrous MgSO4, filtered, and concentrated under vacuum. Brownish yellow crystalline solid, yield

Synthesis and investigation on optical and electrochemical properties of 2,4-diaryl-9-chloro-5,6,7,8-tetrahydroacridines

• Najeh Tka,
• Mohamed Adnene Hadj Ayed,
• Mourad Ben Braiek,
• Mahjoub Jabli and
• Peter Langer

Beilstein J. Org. Chem. 2021, 17, 2450–2461, doi:10.3762/bjoc.17.162

• surfaces around the phenyl groups leading to a significant decrease in their electronic densities. However, thanks to the π-donating effect of two methoxy groups for 4b and 4d, yellow-red regions are present in the phenyl groups and quinoline core. The electrochemical behavior of compound 4c was studied by

Targeting active site residues and structural anchoring positions in terpene synthases

• Anwei Hou and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2021, 17, 2441–2449, doi:10.3762/bjoc.17.161

• incubation of GGPP with the SmTS1 A222V variant. Relative activities of SmTS1 and its variants towards GFPP (blue bars) and GGPP (yellow bars), and the production of compounds 8 (red bars) and 9 (grey bars). Wildtype activity towards GFPP was set to 100%. Means from triplicates, for standard deviations cf

Isolation and characterization of new phenolic siderophores with antimicrobial properties from Pseudomonas sp. UIAU-6B

• Emmanuel T. Oluwabusola,
• Olusoji O. Adebisi,
• Fernando Reyes,
• Kojo S. Acquah,
• Mercedes De La Cruz,
• Larry L. Mweetwa,
• Joy E. Rajakulendran,
• Digby F. Warner,
• Deng Hai,
• Rainer Ebel and
• Marcel Jaspars

Beilstein J. Org. Chem. 2021, 17, 2390–2398, doi:10.3762/bjoc.17.156

• : 3341, 2927, 1670, 1633, 1205; NMR data, see Table 1; HRESIMS (m/z): [M + H]+ calcd for C19H23N2O4, 343.1652; found, 343.1653, Δ = 2.01 ppm. Pseudomobactin A (4): yellow amorphous solid; [α]D25 −17.7 (c 0.05, MeOH); UV (MeOH) λmax, nm (log ε): 260 (3.59), 302 (4.12); IR (cm−1) νmax: 3320, 2930, 1675