ライフサイエンスコーパス: ring current

1 a strong, albeit slightly reduced, diatropic ring current.

2 the presence of a more substantial diatropic ring current.

3 eld, and this also showed a strong diatropic ring current.

4 eared to possess a slightly larger diatropic ring current.

5 rotropiporphyrin that also showed a stronger ring current.

6 confirming the presence of a strong aromatic ring current.

7 stness of the classical benzene diatropic pi ring current.

8 e cyclobutadieno clamps disrupts the benzene ring current.

9 eroxide oxidation ensued yielded bell-shaped ring currents.

10 r magnetic behaviour associated with induced ring currents.

11 d oxidized form display residual macrocyclic ring currents.

12 showed the presence of enhanced diamagnetic ring currents.

13 ects can be characterized by the reversal of ring currents.

14 hey nevertheless retain powerful macrocyclic ring currents.

15 turn, the magnetic field generated by these ring currents affects the chemical shift of carbons on t

16 pocket residues, 4 Phe, 4 Tyr, and 2 upfield ring current aliphatic side chains.

17 quires very high energy and has a paratropic ring current and antiaromatic character.

18 ipsocentric calculation to support diatropic ring currents and hence to be aromatic on the basis of m

19 readily rationalized by analysis of aromatic ring-currents and provide sensitive probes for sites of

20 onfirms the presence of a strong diamagnetic ring current, and the meso-protons show up at 10 ppm, wh

21 currents of its components.The discovery of ring currents around a molecule with a circumference of

22 + 2] or [4n] electrons, respectively-exhibit ring currents around their perimeters.

23 These results highlight ring currents as being critically important to the deter

24 amework S(2)N(4)(CH)(2) supports a diatropic ring current, as does its analogue in which N and CH gro

25 Here we report images of the ring current at Saturn, together with a day-night pressu

26 The ring current branches at the pyrrolic rings taking both

27 ent drift that leads to the formation of the ring current by ions in the several tens of kiloelectron

28 logues showed no indication of a diamagnetic ring current by proton NMR spectroscopy, but addition of

29 These systems also showed large diatropic ring currents by proton NMR spectroscopy that were compa

30 gues of the porphyrins show strong diatropic ring currents by proton NMR spectroscopy where the inter

31 Ring current calculations based on a homology model for

32 Ring current calculations based on homology models or cr

33 The ring current can be highly variable with strong longitud

34 This work demonstrates that a global ring current can be promoted in a macrocycle by adjustin

35 Ring currents can exert a large effect upon the chemical

36 ndicates the presence of a strong paratropic ring current, characteristic of an antiaromatic compound

37 ne-fused annulenes shows further evidence of ring current competition as these allow for observation

38 For the second series a ring current contribution to the shielding tensor was ca

39 resonances which can be accounted for by the ring current contributions of the deoxyguanosinyl and py

40 analytical expressions are used to calculate ring current contributions to the CSA (Deltasigma) of 1H

41 ronger than that of benzene according to the ring-current criterion.

42 Carbasapphyrins retain a strong diatropic ring current due to the presence of 22pi electron deloca

43 r-containing ligands due to the porphyrin pi-ring current effect, which is also present in the di- an

44 due to the strong distance dependence of the ring current effect.

45 rturbation of POPC protons from the aromatic ring-current effect, as well as 1H NMR cross-relaxation

46 ndependent chemical shifts that quantify the ring current effects caused by neighboring molecules.

47 C turn, too distant to be ascribed solely to ring current effects from Phe75.

48 loop sugar on the Pu2 base and the different ring current effects of A or G in this position.

49 iffers by 1.26 ppm, indicative of pronounced ring current effects on the surface of this endohedral f

50 r hydrogen bonding interactions and aromatic ring current effects.

51 to lead to structures that support diatropic ring currents: explicit ab initio calculation of magneti

52 A/MCAD complex is proposed to arise from the ring current field from the isoalloxazine portion of the

53 lene with inactive NH bridges is not how the ring-current flows around the macroring.

54 , neutral aromatic molecule with a diatropic ring current following the sigma-bond path formed by Si

55 on theory reveals a significant paramagnetic ring current in 1, a feature that helps explain the (1)H

56 luding evidence for a diatropic ("aromatic") ring current in 3,3-difluorocyclohexadienyl anion.

57 More generally, the hyperconjugative ring current in a family of C(2v) planar-constrained geo

58 the ring (a 'diatropic' current), while the ring current in an antiaromatic molecule flows in the re

59 The direction of the ring current in an aromatic molecule is such as to gener

60 rum showed that it has a reduced diamagnetic ring current in comparison to other carbaporphyrins.

61 contributions arising from an aromatic-like ring current in cyclopropane, involving six electrons in

62 for conventional pi-ring currents, the sigma-ring current in tangential p-p bonded systems is dominat

63 Appreciable ring current in the 1,2-phosphaborine core, detected in

64 quires much more energy and has a paratropic ring current in the TS pointing to antiaromatic, cyclope

65 ne), both of which exhibit a weak paratropic ring current in their 1H NMR spectra and are oxygen sens

66 he introduction contains the fundamentals of ring currents in aromatic and antiaromatic systems, foll

67 are typically dominated by strong paratropic ring currents in four-membered rings.

68 The relationship between ring currents in molecular and non-molecular rings is po

69 ings provides a motivation for investigating ring currents in molecules of an intermediate size.

70 shifts in cyclopentadienes have a diatropic ring current indicating aromatic, cyclopentadienide anio

71 It was found that the porphyrin ring-current induced (1)H chemical shifts and molecular

72 culations of the effect of the cyt b(5) heme ring current-induced magnetic dipole on cyt c were used

73 ence of CH...pi interaction is provided from ring current-induced upfield displacement of Pro(1) C(al

74 emical shifts for paramagnetic and porphyrin ring current influences in the paramagnetic substrate co

75 only saturated clamps are used, the benzene ring current is essentially unchanged.

76 rins are 19-24 nA/T depending on whether the ring current is forced to pass an NH unit or not.

77 This decrease in annulenic ring current is manifested in the alkene proton chemical

78 Ring-current magnetic shielding of polyimide protons by

79 The ipsocentric ring-current mapping approach is used to evaluate aromat

80 hanges lead to modulation of the strength of ring currents near the site of addition and, in turn, th

81 The porphins have the strongest ring current of ca. 27 nA/T among the investigated porph

82 to intrude into the pi-cloud and diamagnetic ring current of the neighboring acridine.

83 Ring currents of a different nature were observed at Jup

84 ng its oxidation state to suppress the local ring currents of its components.The discovery of ring cu

85 he design of confined ultrafast switching of ring currents of nonplanar molecules and further current

86 ized ring currents, with stronger paratropic ring currents on the pentalene moieties.

87 The attendant ring current perturbations expected from such modulation

88 pect to the fundamental orbital symmetry and ring-current rules, Si bonds at greater internuclear dis

89 ifts at the lesion site were consistent with ring current shielding arising from the BA moiety.

90 the monomer 1,N(2)-epsilondG, attributed to ring current shielding, consistent with their intrahelic

91 e linear correlations that exist between the ring-current shielding shifts for the axial ligand C(1)

92 , as indicated by NOEs and the large upfield ring current shift (approximately 4 ppm) of A37 HN.

93 of Trp25 from solvent exposure and produces ring current shifts as large as 3 ppm.

94 f the NH pairs, such as hydrogen bonding and ring current shifts, and are observed for residues in th

95 The ring-current strengths of the porphins, chlorins, and ba

96 uantities with easily computed Huckel-London ring currents suggests a simply calculated measure for d

97 S(pizz) for each isomer is correlated to the ring-current sum SigmaJ extracted from CDA.

98 the dianion of 4 reveal a distinct diatropic ring current that should aid in its characterization.

99 9(+) (1), which supports a pinched diatropic ring current, the C(2v) transition state (2) for inversi

100 As for conventional pi-ring currents, the sigma-ring current in tangential p-p

101 Further investigations on magnetic ring currents through NICS-XY-scans suggest a global par

102 a reasonable estimate of the contribution of ring currents to the full shielding tensor a series of d

103 ion is developed so that the contribution of ring currents to the full shielding tensor can be calcul

104 nd Bovey only quantifies the contribution of ring currents to the isotropic component of the shieldin

105 ed, allowing an estimate of the influence of ring currents upon the chemical shielding anisotropy (CS

106 changes associated with the styrene aromatic ring current were noted for S-SOA6 H2 and H1', T16 N3H,

107 lder adduct 17 showed an increased diatropic ring current where the internal proton shifted beyond -9

108 affords dications with enhanced diamagnetic ring currents where the internal CH shifts to ca. -3 ppm

109 This contrasts with the Earth's ring current, where there is no rotational modulation an

110 The flavin ring current, which is only present when the enzyme is p

111 evices because the pi electrons can generate ring currents with a variety of directions.

112 for these compounds showed strong diatropic ring currents with the internal CH resonance upfield abo

113 tral naphthalene ring, showed more localized ring currents, with stronger paratropic ring currents on