Metal-Ligand Proton Tautomerism, Electron Transfer, and C(sp3)-H Activation by a 4-Pyridinyl-Pincer Iridium Hydride Complex.

The para-N-pyridyl-based PCP pincer proligand 3,5-bis(di-tert-butylphosphinomethyl)-2,6-dimethylpyridine (pN-tBuPCP-H) was synthesized and metalated to give the iridium complex (pN-tBuPCP)IrHCl (2-H). In marked contrast with its phenyl-based congeners, e.g., (tBuPCP)IrHCl and derivatives, 2-H is highly air-sensitive and reacts with oxidants such as ferrocenium, trityl cation, and benzoquinone. These oxidations ultimately lead to intramolecular activation of a phosphino-t-butyl C(sp3)-H bond and cyclometalation. Considering the greater electronegativity of N than C, 2-H is expected to be less easily oxidized than simple PCP derivatives; cyclic voltammetry and DFT calculations support this expectation. However, 2-H is calculated to undergo metal-ligand-proton tautomerism (MLPT) to give an N-protonated complex that can be described with resonance forms representing a zwitterionic complex (with a negative charge on Ir) and a p-N-pyridylidene (a remote N-heterocyclic carbene) Ir(I) complex. One-electron oxidation of this tautomer is calculated to be dramatically more favorable than direct oxidation of 2-H (ΔΔG° = -31.3 kcal/mol). The resulting Ir(II) oxidation product is easily deprotonated to give metalloradical 2• which is observed by NMR spectroscopy. 2• can be further oxidized to give cationic Ir(III) complex, 2+, which can oxidatively add a phosphino-t-butyl C-H bond and undergo deprotonation to give the observed cyclometalated product. DFT calculations indicate that less sterically hindered analogues of 2+ would preferentially undergo intermolecular addition of C(sp3)-H bonds, for example, of n-alkanes. The resulting iridium alkyl complexes could undergo facile ß-H elimination to afford olefin, thereby completing a catalytic cycle for alkane dehydrogenation driven by one-electron oxidation and deprotonation, enabled by MLPT.

A Randomized, Single Centered, Parallel and Open Labelled Interventional Study on Effectiveness of Clinical Pharmacists on Adverse Event Following Immunization (AEFI) in Pediatric Population.

BACKGROUND: Adverse events are a major threat to any immunization programs, which have proven to be a boon for developing nations like India. Hindering factors, such as inadequate knowledge, inappropriate attitude, incorrect practices, etc., of the guardian affect the vaccination rate. AIM: This study aims to assess the effectiveness of clinical pharmacist intervention on an adverse event following immunization in the pediatric population receiving immunization. METHODS: Pediatric subjects <5 yrs of both genders receiving immunization in a tertiary care hospital during the period of 8 months were considered. Subjects were randomized into control and interventional groups. Pharmaceutical intervention was done in interventional group in the form of patient counselling, and a patient information leaflet. Adverse event following immunization was recorded and analysed for both groups along with Knowledge, Attitude, and Practice scores of guardians' pre and post intervention through customized data collection forms. Microsoft excel and statistical software SPSS IBM version 22 was used to analyse the data. RESULTS: The study was conducted on a total of 88 subjects (n) in which 79 were <2 years, 1 and 8 were between 2-4 years and 4-5 years, respectively. Forty-nine subjects (55.69%) were female, while 39 were male (44.31%) with a response and completion rate of 91.66%. 97.7% of subjects received Bacillus Calmette-Guerin vaccination (majority), while 8.88% received pneumococcal special vaccine (minority). Adverse event following immunization was recorded in 31(35.22%) cases. Knowledge, Attitude and Practice scores increased by 42.17%, 52% and 12.67%, respectively in guardians after clinical pharmacist intervention. CONCLUSION: This study demonstrates that educational inputs, awareness programs, and proper medical professional intervention can act as a helping factor to fight against AEFI and towards the success of an immunization program.

Time spent being malnourished during the first five years of life! An unseen aspect of child malnutrition.

The burden of malnutrition is often estimated in terms of 'prevalence' without considering two important contributing factors: incidence and duration. To illustrate this, we conducted a community-based retrospective cohort study involving 24,278 children enrolled in an integrated child development scheme in India. Anthropometric data of study participants from birth to five years of age were collected from the growth charts maintained by Anganwadi workers. Of all the growth charts reviewed, 1460 (6.0%) children died before their fifth birthday and 4013 (16.5%) were excluded after initial screening because either the growth chart was incomplete (4.8%) or had missing entries (11.7%). Of the remaining 20,265 children included in the study, in the first five years of their life, 35.6% suffered from exclusive moderate malnourishment and 9.4% from severe malnourishment. The most common age groups for the onset of moderate and severe malnutrition were 9-11 months and 12-15 months, respectively. The mode, median and mean duration of time spent by children being severely underweight was 3, 7 and 8.4 months respectively, and being moderately underweight was 8, 11 and 15.1 months, respectively. Thus, a comprehensive strategy for preventing the onset of malnutrition (both moderate and severe) among children is urgently needed.