Development of ruthenium complexes with S-donor ligands for application in synthesis, catalytic acceptorless alcohol dehydrogenation and crossed-aldol condensation.

The reaction of [Ru(dmso)4Cl2] with a potassium salt of four xanthate (RO-C(S)S-; R = Me, Et, iPr and tBu) ligands (depicted as Ln; n = 1-4) in hot methanol afforded a group of mixed-ligand complexes of type [Ru(Ln)2(dmso)2]. The crystal structures of all the four complexes have been determined, which show that the xanthate ligands are bound to the metal center forming four-membered chelates and dmso is coordinated through sulfur and they are mutually cis. The relative thermodynamic stability of this cis and the other possible trans-isomers of these complexes has been assessed with the help of DFT calculations, which have revealed that the cis-isomer is the more stable isomer. The coordinated dmso in the [Ru(Ln)2(dmso)2] complexes could be easily displaced by chelating bidentate ligands (depicted as L') to furnish complexes of type [Ru(Ln)2(L')], as demonstrated through isolation of two such complexes, viz. [Ru(L3)2(bpy)] and [Ru(L2)2(phen)] (bpy = 2,2'-bipyridine and phen = 1,10-phenanthroline). The crystal structure of [Ru(L3)2(bpy)] has been determined and the structure of [Ru(L2)2(phen)] has been optimized by the DFT method. The electronic spectra of the four [Ru(Ln)2(dmso)2] complexes and the two derivatives ([Ru(Ln)2(L')]; n = 3, L' = bpy; n = 2, L' = phen), recorded in dichloromethane solutions, show intense absorptions spanning the visible and ultraviolet regions, which have been analyzed by the TDDFT method. The [Ru(Ln)2(dmso)2] complexes are found to serve as efficient catalyst precursors for the acceptorless dehydrogenation of 2-propanol followed by crossed-aldol condensation with substituted benzaldehydes (and related aldehydes), using tert-butoxide as the co-catalyst, producing dibenzylideneacetone derivatives in good yields.

Clinico-epidemiological profile of burn patients admitted in a tertiary care hospital in coastal South India.

Every year a substantial proportion of deaths in India occur due to burn injuries. Prolonged morbidity as well as temporary and permanent disability due to burns results in a heavy economic loss. The etiological factors of burn injuries vary considerably in different communities and regions and hence the need for detailed epidemiological studies to understand the problem status in different regions. This study was aimed to study the sociodemographic profile of burn patients and to evaluate the causes, manner, and place of occurrence of burns injuries along with its outcome. A registry-based retrospective study was conducted at a tertiary care hospital in coastal South India, and the medical records of all the patients admitted to the burns centre during the year 2009 were reviewed. The data were analyzed using SPSS version 11.5. A total of 101 burn patients were admitted during the study period. The burn patients were aged between 4 months and 80 years with a mean age of 32.11 (± 3.46) years. The overall male to female ratio was 0.83:1. Majority of the patients were Hindus and were married. Flame burns were the most common etiology for sustaining burns (82.2%). Most of the burn injuries were sustained at home (n = 81, 80.2%), and the manner was designated as accidental in 79.2% of the cases. The TBSA involvement in burns ranged from 5 to 100% and the mean TBSA was found to be 45.8 ± 24.7%. A higher TBSA involvement is associated with an increased risk of mortality and this association between TBSA and mortality was found to be statistically significant (P < .05). Mortality rate in our study was 40.9%. Septicemia (n = 24, 63.2%) was the most common cause of death followed by shock (n = 12, 31.6%). Higher mortality is found to be associated with female sex, suicides, and flame burns. This study identifies the epidemiological and clinical features associated with burn injuries in coastal South India. Majority of the burn victims in our study were married females of younger age group. Although the manner of sustaining burns was mostly accidental, females were proportionately more commonly the victims of suicides and homicides than males. Injuries and deaths due to burns are preventable, provided a community-specific preventive program is implemented with a strong educational component.