Unprecedented synthesis of a 14-membered hexaazamacrocycle

• Anastasia A. Fesenko and
• Anatoly D. Shutalev

Beilstein J. Org. Chem. 2023, 19, 1728–1740, doi:10.3762/bjoc.19.126

• -standard approach [44] (see the Supporting Information File 1 for details). The high-resolution mass spectrum (ESI+) of a mixture of 5 and the impurity, in addition to a peak at m/z = 329.1696 [M + H]+ for compound 5, shows a peak at m/z = 319.1862 [M + H]+, consistent with the molecular formula of

• structure (see Supporting Information File 1). The high-resolution mass spectrum (ESI+) confirmed its chemical formula as C12H16N12. Thus, we found that, in contrast to the reported data [40], the reaction between imidate 4 and hydrazine hydrate (4 equiv) in refluxing EtOH for 2 h afforded macrocycle 5 in a

• to 1D and 2D NMR, and HRMS (ESI+) data, the product obtained was triazolo[1,5-c]pyrimidine 13 instead of the expected macrocycle 11. The structure 13 was unambiguously confirmed by its synthesis directly from pyrazolopyrimidine 8 (ethyl orthoformate, 1.3 equiv of HCOOH, reflux, 15 h). Analogously, no

Sulfur-containing spiroketals from Breynia disticha and evaluations of their anti-inflammatory effect

• Ken-ichi Nakashima,
• Naohito Abe,
• Masayoshi Oyama,
• Hiroko Murata and
• Makoto Inoue

Beilstein J. Org. Chem. 2023, 19, 1604–1614, doi:10.3762/bjoc.19.117

• Hitachi U-2900 spectrometer. ECD spectra were acquired with a JASCO J-820 spectropolarimeter and IR spectra were recorded using a Shimadzu FTIR-8400S spectrophotometer. NMR spectra were acquired with a JEOL JNM-ECZ 400S spectrometer with tetramethylsilane as an internal standard. ESI–MS data were obtained

Secondary metabolites of Diaporthe cameroonensis, isolated from the Cameroonian medicinal plant Trema guineensis

• Bel Youssouf G. Mountessou,
• Élodie Gisèle M. Anoumedem,
• Blondelle M. Kemkuignou,
• Yasmina Marin-Felix,
• Frank Surup,
• Marc Stadler and
• Simeon F. Kouam

Beilstein J. Org. Chem. 2023, 19, 1555–1561, doi:10.3762/bjoc.19.112

• sulfuric acid before heating. LC–MS chromatograms were recorded with an UltiMate 3000 Series uHPLC (Thermo Fischer Scientific) using a C18 Acquity UPLC BEH column (2.1 × 50 mm, 1.7 µm) connected to an amazon speed ESI-Iontrap-MS (Bruker). Semi-preparative and/or preparative HPLC systems on normal and

• % B in 19.5 min and then maintaining 100% B for 5 min, flow rate 0.6 mL/min, UV–vis detection 200–640 nm) connected to a MaXis ESI-TOF mass spectrometer (Bruker) (scan range 100–2500 m/z, capillary voltage 4500 V, dry temperature 200 °C). NMR spectra were recorded at 25 °C on a Bruker (Billerica, MA

Synthesis of 5-arylidenerhodanines in L-proline-based deep eutectic solvent

• Stéphanie Hesse

Beilstein J. Org. Chem. 2023, 19, 1537–1544, doi:10.3762/bjoc.19.110

• MHz, DMSO-d6) δ (ppm) 196.8, 169.1, 161.2, 148.8, 121.8, 121.0, 117.8, 110.9, 56.0. HRMS–ESI− (m/z): [M]− calcd for C9H6NO3S2: 240.982814; found, 240.982805. DPPH-scavenging activity Determination of antioxidant activity was performed according to the procedure described in the literature [21]. A DMSO

Selective construction of dispiro[indoline-3,2'-quinoline-3',3''-indoline] and dispiro[indoline-3,2'-pyrrole-3',3''-indoline] via three-component reaction

• Ziying Xiao,
• Fengshun Xu,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2023, 19, 1234–1242, doi:10.3762/bjoc.19.91

• , 127.9, 127.5, 127.5, 127.1, 127.1, 127.0, 126.2, 125.9, 125.6, 124.9, 110.9, 110.3, 102.3, 62.3, 60.3, 50.0, 49.4, 44.4, 44.2, 42.5, 42.4, 32.9, 29.0, 27.6, 13.5 ppm; IR (KBr) ν: 3504, 3024, 3010, 2995, 2985, 1847, 1711, 1603, 1517, 1400, 1299, 1250, 1053, 953, 841 cm−1; HRMS (ESI-TOF): [M + Na]+ calcd

• , 1526, 1545, 1368, 1285, 1145, 1025, 956, 882 cm−1; HRMS (ESI-TOF): [M + H]+ calcd. for C48H44ClN3O5, 760.2937; found, 760.2921. Crystal structure of dispiro compound 3a. Crystal structure of compound 4a. Representative cascade reactions of Michael adducts of 3-methyleneoxindoles. Proposed reaction

Two new lanostanoid glycosides isolated from a Kenyan polypore Fomitopsis carnea

• Winnie Chemutai Sum,
• Sherif S. Ebada,
• Didsanutda Gonkhom,
• Cony Decock,
• Rémy Bertrand Teponno,
• Josphat Clement Matasyoh and
• Marc Stadler

Beilstein J. Org. Chem. 2023, 19, 1161–1169, doi:10.3762/bjoc.19.84

• at 0.6 mL/min and the UV–vis detection made at 210 nm and 190–600 nm. The isolates were analyzed on a MaXis ESI-TOF (time-of-flight) mass spectrometer (Bruker Daltonics) for the HRESIMS data, in the positive ionization mode. This was coupled to an Agilent 1260 series HPLC–UV system (Agilent

• , nm (log ε): 196.5 (1.7); NMR data (1H NMR: 500 MHz, 13C NMR: 125 MHz in methanol-d4) see Table 1; HRMS–ESI (m/z): [M + Na]+ calcd for C43H68NaO12+, 799.4603; found, 799.4604; [2M + Na]+ calcd for C86H136NaO13+, 1575.9314; found, 1575.9321. Forpinioside C (2): pale yellow oil; +30 (c 0.1, MeOH); UV

• –vis (MeOH) λmax, nm (log ε): 196.5 (1.7); NMR data (1H NMR: 500 MHz, 13C NMR: 125 MHz in methanol-d4) see Table 1; HRMS–ESI (m/z): [M – H2O + H]+ calcd for C43H67O12+, 775.4627; found, 775.4625; [M + Na]+ calcd for C43H68NaO13+, 815.4552; found, 815.4550; [2M + H]+ calcd for C86H137O26+, 1607.9212

The effect of dark states on the intersystem crossing and thermally activated delayed fluorescence of naphthalimide-phenothiazine dyads

• Liyuan Cao,
• Xi Liu,
• Xue Zhang,
• Jianzhang Zhao,
• Fabiao Yu and
• Yan Wan

Beilstein J. Org. Chem. 2023, 19, 1028–1046, doi:10.3762/bjoc.19.79

• , J = 7.51 Hz, 2H), 6.85–6.88 (m, 2H), 6.77–6.80 (m, 2H), 6.08 (d, J = 8.13 Hz, 2H); 13C NMR (CDCl3, 125 MHz) δ 162.9, 158.1, 151.9, 142.6, 138.2, 138.2, 130.8, 130.3, 128.0, 127.6, 124.6, 123.5, 121.1, 117.5, 116.4, 111.8; HRMS–ESI (m/z): [M + H]+ calcd for C30H17FN2O2S, 489.0995; found, 489.1072

• ) δ 164.1, 163.0, 143.7, 143.4, 138.8, 133.2, 133.0, 131.5, 130.5, 130.3, 130.2, 128.3, 128.0, 124.2, 122.1, 120.6, 115.8; HRMS–ESI (m/z): [M + H]+ calcd for C30H18N2O2S, 471.1089; found, 471.1159. Synthesis of NI-PTZ-CH3 NI-PTZ-CH3 was synthesized with a method similar to that of NI-PTZ-F. The crude

• , 127.1, 123.3, 120.6, 115.8, 21.3; HRMS–ESI (m/z): [M + H]+ calcd for C31H20N2O2S, 485.1245; found, 485.1325. Synthesis of NI-PTZ-OCH3 NI-PTZ-OCH3 was synthesized by a method similar to that of NI-PTZ-F. The crude product was purified by column chromatography (silica gel, DCM/PE 1:5, v:v). The product

Eschenmoser coupling reactions starting from primary thioamides. When do they work and when not?

• Lukáš Marek,
• Jiří Váňa,
• Jan Svoboda and
• Jiří Hanusek

Beilstein J. Org. Chem. 2023, 19, 808–819, doi:10.3762/bjoc.19.61

• detected by ESI–MS analysis of the reaction mixture as it has a different fragmentation pattern (easily loses water – see Supporting Information File 1, Figure S1) than the starting isobaric salt 6a (loses benzonitrile and thiobenzamide). However, all attempts to isolate intermediate 7a have always failed

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

• 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

• /methanol mixture. The purity of the prepared products was considered enough for use in UV experiments without additional purification. Methods. Low-resolution mass spectra were measured with a Shimadzu LCMS-2020 spectrometer. Samples were ionized by electrospray technique (ESI) and detected by quadrupole

• or TOF. The drying and nebulizer gas was nitrogen. High-resolution mass spectra were measured with an Agilent Technologies 6530 Accurate-Mass Q-TOF LC/MS spectrometer. Samples were ionized by electrospray technique (ESI) and detected by quadrupole or TOF. UV–vis spectroscopy spectra were measured

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

• 2.50 and δC 39.52, respectively. The UHPLC–MS data were recorded on an Ultimate 3000 RS UHPLC coupled to a Thermo Fisher Scientific ISQEC single quadruple ESI mass spectrometer using an analytical Thermo Scientific Accucore C18 (2.6 μm, 80 Å, 150 × 2.1 mm). HRESIMS data was acquired on a Bruker maXis

• II ETD ESI-qTOF. Phenomenex Strata solid phase extraction (SPE) cartridges (3 cc, polypropylene, single fritted) were used for the small-scale marine sponge extractions. GRACE Davisil (35–70 µm, 60 Å) C18-bonded silica was used for pre-absorption work before reversed-phase (RP) HPLC. The preabsorbed

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

• for the purification of ApppI(d2) [21]. HRMS spectra were recorded on a qTOF mass spectrometer using electrospray ionization (ESI) in negative mode. The purity of the products was determined from the 1H and 31P NMR spectra to be ≥95%, unless stated otherwise. ApppI(d2)⋅3.25 and ⋅5.25 TBA salts: ATP

• TBA salt), 22.6, 20.1 (from TBA salt), 13.8 (from TBA salt, used as calibration peak: value marked same as in the earlier characterization of ApppI [20]); 31P NMR (D2O): δ −11.2 d (2JPP = 19.4), −11.7 d (2JPP = 19.4), −23.4 t (2JPP = 19.4); HRMS–ESI (qTOF, m/z): [M − H]− calcd for C15H212H2N5O13P3

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

• rotations were carried out on an Autopol VI automatoc polarimeter. UV spectra were recorded on a Shimadzu UV-2401 PC spectrophotometer. IR spectra (KBr) were determined on a Bruker Vertex 70 infrared spectrometer. ESI and HRESIMS were performed on an UPLCIT-TOF spectrometer. ECD spectra were obtained on a

Synthesis of meso-pyrrole-substituted corroles by condensation of 1,9-diformyldipyrromethanes with pyrrole

• Baris Temelli and
• Pinar Kapci

Beilstein J. Org. Chem. 2022, 18, 1403–1409, doi:10.3762/bjoc.18.145

• hertz (Hz). IR spectra were recorded on FTIR spectrometer (Thermo Scientific, Nicolet IS10). HRMS were measured in ESI mode and the mass analyzer of the HRMS was TOF (Agilent 6224 TOF LC–MS). Flash column chromatography was performed on silica gel (230–400 mesh). 5-Substituted dipyrromethanes [35] and

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

Cyclodextrin-based Schiff base pro-fragrances: Synthesis and release studies

• Attila Palágyi,
• Jindřich Jindřich,
• Juraj Dian and
• Sophie Fourmentin

Beilstein J. Org. Chem. 2022, 18, 1346–1354, doi:10.3762/bjoc.18.140

• –97%). This method allows for easy recovery of the unreacted aldehyde as well as separation of the product (just by extraction by hexane and drying under reduced pressure) without its decomposition. The structure of the final imines was confirmed by 1H NMR, 13C NMR, ESI–MS, and the release of the VOCs

• 5-methylfurfural (2j) and 3.1 min for heptanal (2h). The mass spectra were measured by the Bruker ESQUIRE 3000 ES-ion trap and the samples were ionized using an electrospray technique (ESI). The samples were dissolved in methanol. Specific optical rotation was measured by the Rudolph Research

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

• ), 1.70 (td, J = 0.5, 3.2 Hz, 3H), 1.25 (t, J = 7.1 Hz, 3H) ppm; 13C NMR (75 MHz, CDCl3, DEPT) δ 204.8 (C), 174.0 (C), 101.6 (C), 77.0 (CH2), 71.5 (CH), 60.5 (CH2), 30.4 (CH2), 30.0 (CH2), 14.5 (CH3), 14.2 (CH3) ppm; HRMS–ESI (Q-TOF, m/z): [M + H]+ calcd for C10H17O3, 185.1178; found, 185.1158. A lactone

• , 3H) ppm; 13C{1H} NMR (75 MHz, CDCl3, DEPT) δ 206.0 (C), 177.0 (C), 98.0 (C), 80.4 (CH), 77.5 (CH2), 28.5 (CH2), 26.1 (CH2), 15.0 (CH3) ppm; HRMS–ESI (Q-TOF, m/z): [M + H]+ calcd for C8H11O2,139.0759; found, 139.0782. Silver(I)-promoted cyclization of ethyl 4-hydroxy-5-methylhepta-5,6-dienoate (3) A

• ), 86.4 (CH), 74.7 (CH2), 60.3 (CH2), 29.4 (CH2), 28.9 (CH2), 14.2 (CH3), 12.3 (CH3) ppm; HRMS–ESI (Q-TOF, m/z): [M + H]+ calcd for C10H17O3,185.1172; found, 184.1162. Synthesis of 2-methyl-4-(3-methyl-2,5-dihydrofuran-2-yl)butan-2-ol (6) Under an N2 atmosphere, methylmagnesium bromide (3 M in Et2O, 0.075

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

• electrospray ionization (ESI) source in a positive mode. The temperatures of the source were set at 300 °C. Curtain gas (25 psi) chambers were filled with high-purity nitrogen. The capillary voltage was constantly kept at 5500 V. Collision energies was set at 10 V and zero collision energy spread. IDA mode was

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

• procedures NMR spectra were acquired on Bruker 500 and 600 MHz AVANCE NEO spectrometers with TMS as an internal standard. HPLC–UV analysis was performed on an Agilent 1260 Infinity II HPLC system. UHPLC–HRMS analysis was performed on a Waters Synapt-G2-Si UHPLC-ESI-QToF-MS system. UV and CD spectra were

• ) λmax (log ε) 257, 304 nm; for NMR spectral data, see Table S4, Supporting Information File 1; HRMS–ESI (m/z): [M + H]+ calcd for C31H20O9, 537.1180; found, 537.1206. Cattleyaisoflavone B (2): yellowish powder; UV (MeOH) λmax 255, 310 nm; for NMR spectral data, see Table S5, Supporting Information File

•  1; HRMS–ESI (m/z): [M + H]+ calcd for C30H18O8, 507.1074; found, 507.1091. Cattleyaisoflavone C (3): white powder; UV (MeOH) λmax 254, 300 nm; for NMR spectral data, see Table S6, Supporting Information File 1; HRMS–ESI (m/z): [M + NH+ calcd for C30H18O8, 507.1074; found, 507.1091. Feeding

Synthesis of N-phenyl- and N-thiazolyl-1H-indazoles by copper-catalyzed intramolecular N-arylation of ortho-chlorinated arylhydrazones

• Yara Cristina Marchioro Barbosa,
• Guilherme Caneppele Paveglio,
• Claudio Martin Pereira de Pereira,
• Sidnei Moura,
• Cristiane Storck Schwalm,
• Gleison Antonio Casagrande and
• Lucas Pizzuti

Beilstein J. Org. Chem. 2022, 18, 1079–1087, doi:10.3762/bjoc.18.110

• electrospray ionization (ESI) source (MicrOTOF-QII, Bruker Scientific) in positive mode. The compounds were individually dissolved in a solution of 50% chromatographic grade MeCN and 50% deionized H2O + 0.1% formic acid. General experimental procedure for the synthesis of hydrazones 1a–i In a 100 mL round

Electrochemical Friedel–Crafts-type amidomethylation of arenes by a novel electrochemical oxidation system using a quasi-divided cell and trialkylammonium tetrafluoroborate

• Hisanori Senboku,
• Mizuki Hayama and
• Hidetoshi Matsuno

Beilstein J. Org. Chem. 2022, 18, 1040–1046, doi:10.3762/bjoc.18.105

• spectra were measured at Instrumental Analysis Support Office, the Frontier Chemistry Center, Faculty of Engineering, Hokkaido University. ESI mass spectra were measured at the Instrumental Analysis Division, Global Facility Center, Creative Research Institution, Hokkaido University. The authors would

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

• 12 degrees of unsaturation based on the HRMS–ESI data (m/z 347.0893 [M + Na]+, calcd for C19H16O5Na+, 347.0890) (Figure S1, Supporting Information File 1). Comprehensive analysis of the 1H and 13C NMR data (Table 1, Figures S3 and S4, Supporting Information File 1) and HSQC data (Figure S5

• . Furthermore, the absolute configuration of C-4 and C-5 in compound 1 was also confirmed as 4R and 5S by X-ray crystallography (Figure 2). (±)-Daturamycin B (2) was isolated as a white powder, and its molecular formula was determined as C17H14O3 by HRMS–ESI data (m/z 289.0833 [M + Na]+, calcd for C19H16O5Na

• , the DatA protein was expressed and purified (Figure 4B). Incubating DatA with substrate 7 and ATP resulted in a new product 8, which was confirmed by HRMS–ESI data (m/z 291.0663 [M − H]−, calcd for ([C18H12O4] − H)−, 291.0663) (Figure S22, Supporting Information File 1). The product was not present in

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

• , 1H, CH2), 2.36 (s, 3H, CH3), 1.41 (t, J = 6.8 Hz, 3H, CH3), 1.14 (t, J = 6.8 Hz, 3H, CH3); 13C NMR (100 MHz, CDCl3) δ 163.2, 159.2, 152.7, 139.0, 136.8, 129.6, 129.5, 124.7, 113.7, 113.5, 86.9, 63.2, 62.7, 52.3, 38.1, 21.1, 13.9, 13.7; HRMS–ESI (m/z): [M + Na]+ calcd for C20H20NaN2O5, 391.1270; found

• = 7.2 Hz, 3H, CH3); 13C NMR (100 MHz, CDCl3) δ 166.5, 164.2, 163.4, 161.1, 160.4, 159.5, 159.4, 153.7, 150.8, 142.6, 131.8, 129.9, 127.8, 126.9, 125.9, 124.8, 122.9, 117.5, 114.7, 113.6, 113.4, 86.0, 72.7, 64.3, 62.5, 62.0, 61.8, 55.4, 55.3, 52.9, 51.4, 13.9, 13.8, 13.7, 13.6; HRMS–ESI (m/z): [M + Na

Anti-inflammatory aromadendrane- and cadinane-type sesquiterpenoids from the South China Sea sponge Acanthella cavernosa

• Shou-Mao Shen,
• Qing Yang,
• Yi Zang,
• Jia Li,
• Xueting Liu and
• Yue-Wei Guo

Beilstein J. Org. Chem. 2022, 18, 916–925, doi:10.3762/bjoc.18.91

• ; ECD (MeCN) λ max, nm (Δε): 222 (−9.7), 257 (+7.2), 340 (+1.3); IR (KBr) νmax: 3435, 2956, 2927, 2872, 1644, 1383, 1261, 1109, 1037 cm−1; 1H and 13C NMR data, see Table 1; HRMS–ESI (m/z): [M + H]+ calcd for C15H23O2, 235.1693; found, 235.1700. ent-4β,10α-Dihydroxyaromadendrane (2): colorless crystal

• ; mp 117.0–118.0 °C; +23.8 (c 0.40, MeOH). (+)-Maninsigin D [(+)-4]: white powder; +26.0 (c 0.08, MeOH); ECD (MeCN) λmax, nm (Δε): 203 (−0.5), 218 (+0.2); IR (KBr) νmax: 2925, 1699, 1632, 1435, 1384, 1259, 1243, 1116, 1069 cm−1; 1H and 13C NMR data, see Table 1; HRMS–ESI (m/z): [M + H]+ calcd for

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

• out on a Dual-ESI Q-TOF 6520 (Agilent Technologies) mass spectrometer. The starting compounds 1 [39], 2 [39] and 19 [40] were prepared following the reported methods. Synthetic details, characterization and analytical data as well as 1H and 13C NMR spectra of all synthesized compounds are presented in