Investigation of stable solid diazonium salt by molecular structure, Hirshfeld surface analysis, optical and electrochemical studies, and applications.

The title compound is a new pyrazolone derivative which was synthesized starting from p-sulphophenyl-3-methyl-5-pyrazolone (1) by nitrosation at low temperature to afford the corresponding p-sulphophenyl-3-methyl-4-nitroso-5-pyrazolone which can exist both in nitroso (2a) and oxime tautomeric forms (2b). Reduction of the latter using zinc with hydrochloric acid furnished the 4-amino-p-sulphophenyl-3-methyl-5-pyrazolone (3). The diazotization of (3) under careful control of temperature and pH afforded the p-sulphophenyl-3-methyl-5-pyrazolone diazonium salt (4) which was re-crystallized from acidified ethanol to afford crystal suitable for X-ray studies. UV-visible spectrum and cyclic voltammetric studies were also carried out indicating λmax at 420 nm and HOMO-LUMMO energy gap was also calculated (Eg) of 2.95 eV. The molecular and crystal structures of the compound were clarified by single crystal X-ray diffraction indicated that it crystallizes as the sodium salt in the triclinic space group P -1, with the 4-azo-pyrazolone and the sulphophenyl groups being nearly coplanar. To get an insight to the intermolecular interactions in the crystal, a Hirshfeld surface analysis was also carried out.

Effect of HCV infection on hepatic fibrosis in patients of thalassaemia major.

OBJECTIVE: To investigate the effect of HCV infection on hepatic fibrosis in patients of thalassaemia major with iron overload in order to modify Pesaro criteria for classification into prognostic groups for allogenic haemopoietic stem cell transplant in these patients. DESIGN: Cross-sectional comparative study. PLACE AND DURATION OF STUDY: Armed Forces Institute of Pathology, Armed Forces Bone Marrow Transplant Center and Departments of Pediatrics of Military Hospital and Combined Military Hospital, Rawalpindi, from July 2003 to June 2004. SUBJECTS AND METHODS: Twenty-eight HCV- and 18 HCV+ patients of thalassaemia major, who were prospective recipients of allogeneic bone marrow transplant, were included in the study. Serum ferritin was estimated by chemiluminescent immunoassay. Degree of fibrosis in liver biopsy was scored using Knodell s scoring system. Correlation between the two was evaluated statistically through Pearson s correlation coefficient. RESULTS: Mean serum ferritin was lower and degree of hepatic fibrosis was less in hepatitis C negative patients of TM. The correlation between serum ferritin and the degree of hepatic fibrosis was much stronger in hepatitis C negative patients with r value of 0.507 and p value of 0.006, which was statistically significant. CONCLUSION: A strong correlation between serum ferritin and degree of hepatic fibrosis was observed in patients of thalassaemia major not infected with hepatitis C infection. Serum ferritin levels alone are, therefore, not sufficient to assess degree of fibrosis in HCV positive patients of TM.