15 research outputs found
X-ray crystal structure of new monohydrate of 2-thioxoimidazolidin-4-one derivative and structural comparison with its analogs; visualizing intermolecular interactions with Hirshfeld surface analysis
Association between age at disease onset of anti-neutrophil cytoplasmic antibody-associated vasculitis and clinical presentation and short-term outcomes
Objectives: ANCA-associated vasculitis (AAV) can affect all age groups. We aimed to show that differences in disease presentation and 6 month outcome between younger- A nd older-onset patients are still incompletely understood. Methods: We included patients enrolled in the Diagnostic and Classification Criteria for Primary Systemic Vasculitis (DCVAS) study between October 2010 and January 2017 with a diagnosis of AAV. We divided the population according to age at diagnosis: <65 years or âĽ65 years. We adjusted associations for the type of AAV and the type of ANCA (anti-MPO, anti-PR3 or negative). Results: A total of 1338 patients with AAV were included: 66% had disease onset at <65 years of age [female 50%; mean age 48.4 years (s.d. 12.6)] and 34% had disease onset at âĽ65 years [female 54%; mean age 73.6 years (s.d. 6)]. ANCA (MPO) positivity was more frequent in the older group (48% vs 27%; P = 0.001). Younger patients had higher rates of musculoskeletal, cutaneous and ENT manifestations compared with older patients. Systemic, neurologic,cardiovascular involvement and worsening renal function were more frequent in the older-onset group. Damage accrual, measured with the Vasculitis Damage Index (VDI), was significantly higher in older patients, 12% of whom had a 6 month VDI âĽ5, compared with 7% of younger patients (P = 0.01). Older age was an independent risk factor for early death within 6 months from diagnosis [hazard ratio 2.06 (95% CI 1.07, 3.97); P = 0.03]. Conclusion: Within 6 months of diagnosis of AAV, patients >65 years of age display a different pattern of organ involvement and an increased risk of significant damage and mortality compared with younger patients
X-ray, 31P CP/MAS, and single-crystal NMR studies, and 31P DFT GIAO calculations of inclusion complexes of bis[6-O,6-O'-(1,2:3,4- diisopropylidene-alpha-D-galactopyranosyl)thiophosphoryl] disulfide: the importance of C-H...S=P contacts in the solid state.
Bis[6-O,6-Oâ˛-(1,2:3,4-diisopropylidene-Îą-D-galactopyranosyl)thiophosphoryl] disulfide shows a strong tendency to form inclusion compounds. The crystal and molecular structure of eight different solvates was established by X-ray analysis. The results indicate three different types of disulfide arrangements in the crystal lattice. By means of 31P CP/MAS NMR experiments the principal values δ11, δ22, and δ33 of the 31P chemical shift tensor were obtained for each form. The orientation of its principal axes with respect to a molecular frame was investigated by means of 31P CP and single-crystal NMR for the complex with propan-2-ol. The principal axis 1 of both chemically equivalent phosphorus atoms is nearly parallel to the P[BOND]S bond and the principal axis 3 is very close to the P[DOUBLE BOND]S bond. DFT GIAO calculations of the model compound (EtO)2(S)P1SSP2(S)(OEt)2 allowed assignment of the experimental chemical shift curves to the magnetically nonequivalent atoms P1 and P2. The maximum difference between calculated angles (â˘âi[BOND]P[BOND]X)calcd and experimental angles (â˘âi[BOND]P[BOND]X)exptl is 8.3° and the rms distance 3.8° (i=principal axes 1, 2, 3; X=S, -S-, -O1-, -O2-). The influence of C[BOND]Hâ
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S weak hydrogen bonding on phosphorus shielding was tested theoretically (31P DFT GIAO) employing the dimethoxythiophosphoryl disulfideâ
CH4 complex as a model compound. The sensitivity of 31P δii parameters to intermolecular forces is demonstrated
X-ray, 31P CP/MAS, and single-crystal NMR studies, and 31P DFT GIAO calculations of inclusion complexes of bis[6-O,6-O-(1,2:3,4- diisopropylidene-Îą-D-galactopyranosyl)thiophosphoryl] disulfide: the importance of C-H...S=P contacts in the solid state
Bis[6-O,6-O-(1,2:3,4-diisopropylidene-alpha-D-galactopyranosyl) thiophosphoryl] disulfide shows a strong tendency to form inclusion compounds. The crystal and molecular structure of eight different solvates was established by X-ray analysis. The results indicate three different types of disulfide arrangements in the crystal lattice. By means of 31P CP/MAS NMR experiments the principal values δ 11, δ 22, and δ 33 of the 31P chemical shift tensor were obtained for each form. The orientation of its principal axes with respect to a molecular frame was investigated by means of 31P CP and single-crystal NMR for the complex with propan-2-ol. The principal axis 1 of both chemically equivalent phosphorus atoms is nearly parallel to the P-S bond and the principal axis 3 is very close to the P=S bond. DFT GIAO calculations of the model compound (EtO)2(S)P1SSP2(S)-(OEt)2 allowed assignment of the experimental chemical shift curves to the magnetically nonequivalent atoms P1 and P2. The maximum difference between calculated angles [symbol: see text] i-P-X)calcd and experimental angles [symbol: see text] i-P-X)exptl is 8.3 degrees and the rms distance 3.8 degrees (i = principal axes 1, 2, 3; X = S, -S-, -O1-, -O2-). The influence of C-H...S weak hydrogen bonding on phosphorus shielding was tested theoretically (31P DFT GIAO) employing the dimethoxythiophosphoryl disulfide.CH4 complex as a model compound. The sensitivity of 31P delta ii parameters to intermolecular forces is demonstrated