Search results
Search for "1JC,H" in Full Text gives 8 result(s) in Beilstein Journal of Organic Chemistry.
Chemical synthesis of C6-tetrazole ᴅ-mannose building blocks and access to a bioisostere of mannuronic acid 1-phosphate
Beilstein J. Org. Chem. 2021, 17, 1527–1532, doi:10.3762/bjoc.17.110
- for glycosylation of 3-(benzyloxycarbonylamino)-1-propanol and furnished a regioisomeric and anomeric mixture in low yield (34%, with 20% recovered starting material and 18% hydrolysed donor, 3:1, α/β). The β-linked (minor) anomer was identified through 1JC-H coupling constant data (J = 156 Hz
Nocarimidazoles C and D, antimicrobial alkanoylimidazoles from a coral-derived actinomycete Kocuria sp.: application of 1JC,H coupling constants for the unequivocal determination of substituted imidazoles and stereochemical diversity of anteisoalkyl chains in microbial metabolites
Beilstein J. Org. Chem. 2020, 16, 2719–2727, doi:10.3762/bjoc.16.222
- both are 4-alkanoyl-5-aminoimidazoles with a 6-methyloctanoyl or decanoyl chain, respectively. Two possible positions of the amino group on the imidazole rings (C-2 and C-5) posed a challenge in the structure study, which was settled by the measurement of 1JC,H coupling constants for comparison with
- MIC ranges of 6.25–25 μg/mL. Keywords: 1JC,H; alkanoylimidazoles; anteiso; Kocuria; nocarimidazole; Introduction The phylum Actinobacteria contains bacterial genera most prolific as producers of novel natural products with high structural diversity, unique modes of action, and potent bioactivities
- correlation from H-2 to C-6 established the linkage between the chain part and the imidazole ring (Figure 2). The remaining question was whether the amino group is bound to C-2 or C-5 in the imidazole ring. A literature survey suggested a diagnostic use of 1JC,H coupling constants [23]. In imidazole and ʟ
Conformational signature of Ishikawa´s reagent using NMR information from diastereotopic fluorines
Beilstein J. Org. Chem. 2019, 15, 506–512, doi:10.3762/bjoc.15.44
- interaction nX → σ*C–H/F (X = electron donor atom, usually oxygen) seems to contribute to the magnitude of 1JC–H/F, since the resonance structure originated from this interaction exhibits a longer and weaker C–Hax/Fax bond relative to C–Heq/Feq, thus reducing 1JC–Hax/Fax relative to 1JC–Heq/Feq. In turn, the
Investigation of the role of stereoelectronic effects in the conformation of piperidones by NMR spectroscopy and X-ray diffraction
Beilstein J. Org. Chem. 2015, 11, 1973–1984, doi:10.3762/bjoc.11.213
- a chair–boat conformation, while those in 2,4-diphenyl-3-azabicyclo[3.3.1]nonan-9-ones, compounds 3–8, adopt a chair–chair conformation because of stereoelectronic effects. These stereoelectronic effects were analyzed by the 1JC–H coupling constants, which were measured in the 13C satellites of the
- delocalization interactions from electrons have a relatively important Fermi contact contribution [45]. For example in cyclohexane the spin–scalar coupling constant of the equatorial hydrogen (Heq) is 4 Hz higher (1JC,Heq) than the axial one (1JC,Hax). This difference in the 1JC,H values has been explained in
- , while C(5), C(6), C(7), and C(8) shifted to δ = 54.49, 29.23, 21.54, and 36.96, respectively. The carbonyl carbon is located at 218.01 ppm. Table S2 (Supporting Information File 1) lists all of the 13C chemical shifts and 1JC,H values. The conformation of the piperidones was determined in solution
De novo synthesis of D- and L-fucosamine containing disaccharides
Beilstein J. Org. Chem. 2013, 9, 332–341, doi:10.3762/bjoc.9.38
- deprotected monomer L-13 and disaccharide 19 were obtained in similar yields and selectivities (Scheme 6B). Diagnostic 1JC–H analysis also corroborated the formation of the β-glycosydic linkages (Scheme 6B). Linker-terminated disaccharide 19 represents the terminal unit of the P. aeruginosa serotype O11 O
Algicidal lactones from the marine Roseobacter clade bacterium Ruegeria pomeroyi
Beilstein J. Org. Chem. 2012, 8, 941–950, doi:10.3762/bjoc.8.106
- ), 5.24 (dt, 2JH,H = 1.2 Hz, 3JH,H = 17.2 Hz, 1H, CH2), 5.12 (dt, 2JH,H = 1.2 Hz, 3JH,H = 10.5 Hz, 1H, CH2), 1.93 (dd, 4JH,H = 1.1, 1.6 Hz, 3H, CH3), 1.34 (d, 3JH,H = 6.5 Hz, 1JC,H = 127.8 Hz, 3H, CH3); 13C NMR (100 MHz, CDCl3) δ 166.4 (CO), 137.7 (CH), 136.6 (Cq), 125.4 (CH2), 115.5 (CH2), 77.1 (CH
- , 1H, CH), 5.54–5.52 (m, 1H, CH2), 5.25–5.19 (m, 2H, CH, CH2), 5.17–5.13 (m, 1H, CH2), 1.93 (d, 4JH,H = 1.0 Hz, 3H, CH3), 1.69 (quintd, 3JH,H = 7.3 Hz, 4JH,H = 2.7 Hz, 2H, CH2), 0.90 (t, 3JH,H = 7.4 Hz, 1JC,H = 126.2 Hz, CH3); 13C NMR (100 MHz, CDCl3) δ 166.7 (CO), 136.6 (Cq), 136.3 (CH), 125.1 (CH2
- acetate 3:1): Rf 0.27; GC (BPX-5): I = 1017; 1H NMR (400 MHz, CDCl3) δ 7.02 (quint, 3JH,H = 4JH,H = 1.6 Hz, 1JC,H = 171.3 Hz, 1H, CH), 5.01–4.94 (m, 1H, CH), 1.90 (dd, 4JH,H = 5JH,H = 1.6 Hz, 1JC,H = 128.8 Hz, 3H, CH3), 1.39 (d, 3JH,H = 6.8 Hz, 1JC,H = 129.0 Hz, 3H, CH3); 13C NMR (100 MHz, CDCl3) δ 173.9
Synthesis of glycoconjugate fragments of mycobacterial phosphatidylinositol mannosides and lipomannan
Beilstein J. Org. Chem. 2011, 7, 369–377, doi:10.3762/bjoc.7.47
- measurement of the 1JC,H coupling constants for the anomeric carbons of the newly formed products. Each coupling constant was >170 Hz, thereby showing that all new O-glycosidic linkages were α-configured (Supporting Information File 2) [42]. Global debenzoylation of disaccharide 20 and trisaccharide 25 with
Poly(glycolide) multi-arm star polymers: Improved solubility via limited arm length
Beilstein J. Org. Chem. 2010, 6, No. 67, doi:10.3762/bjoc.6.67
- for gs-COSY and gs-NOESY experiments were used. The refocusing delays for the inverse hetero-correlations were set to 3.45 and 62.5 ms, corresponding to 1JC,H = 145 Hz and nJC,H = 8 Hz, respectively. For SEC measurements in DMF (containing 1 g/l of lithium bromide as an additive), an Agilent 1100
Other Beilstein-Institut Open Science Activities
