14 research outputs found

    Acetic anhydride induced rearrangement and Grignard addition on C-phenyl-N-(1-methyl-2-aryl)ethyl nitrones

    No full text
    646-653This article describes the acetic anhydride induced rearrangement of nitrone to amide and the addition of Grignard reagent to the nitrones yielding substituted hydroxylamines. It has been found that the conversion of C-phenyl-N-(1-methyl-2-aryl)ethyl nitrones 1 to N-(1-methyl-2-arylethyl)arylcarboxamides 2 is clean, selective and quantitative under solventless condition with microwave irradiation. The Grignard addition on nitrones 1 with phenylmagnesium bromide has been found to be very effective giving hydroxylamine derivatives quantitatively. All the synthesised compounds have been fully characterized by NMR and single crystal X ray analysis. </span

    Synthesis and antioxidant characteristic of novel thiazolidinone derivatives

    No full text
    377-383A series of novel thiazolidinone derivatives have been synthesized by solventless condensation of N-alkylamines with arylaldehydes at room temperature followed by a microwave assisted solventless addition of thioglycollic acid to the resultant imines. The synthesized compounds are characterized by 1H NMR, 13C NMR, MS and X-ray techniques and one of the synthesized thiazolidinones has been evaluated for its antioxidant property

    An efficient solventless synthesis of ⍺-aryl-N-[1-methyl-2- (2/4-chlorophenyl)] ethyl nitrones and their antimicrobial activity

    No full text
    276-282An efficient solventless synthesis of ⍺-aryl-N-[1-methyl-2-(2/4-chlorophenyl)]ethyl nitrones has been achieved in excellent yield. The compounds are characterized by NMR and X-ray studies. The antimicrobial activities of the synthesized compounds have also been investigated

    Birth anthropometry among three Asian racial groups in Singapore: proposed new growth charts.

    No full text
    10.1136/archdischild-2022-324693Arch Dis Childarchdischild-2022-324693

    Estimation of fat-free mass in Asian neonates using bioelectrical impedance analysis

    No full text
    The aims of this study were to develop and validate a prediction equation of fat-free mass (FFM) based on bioelectrical impedance analysis (BIA) and anthropometry using air-displacement plethysmography (ADP) as a reference in Asian neonates and to test the applicability of the prediction equations in an independent Western cohort. A total of 173 neonates at birth and 140 at two weeks of age were included. Multiple linear regression analysis was performed to develop the prediction equations in a two-third randomly selected subset and validated on the remaining one-third subset at each time point and in an independent Queensland cohort. FFM measured by ADP was the dependent variable, and anthropometric measures, sex and impedance quotient (L/R50) were independent variables in the model. Accuracy of prediction equations was assessed using intra-class correlation and Bland-Altman analyses. L/R50 was the significant predictor of FFM at week two but not at birth. Compared with the model using weight, sex and length, including L/R50 slightly improved the prediction with a bias of 0·01 kg with 2 sd limits of agreement (LOA) (0·18, -0·20). Prediction explained 88·9 % of variation but not beyond that of anthropometry. Applying these equations to the Queensland cohort provided similar performance at the appropriate age. However, when the Queensland equations were applied to our cohort, the bias increased slightly but with similar LOA. BIA appears to have limited use in predicting FFM in the first few weeks of life compared with simple anthropometry in Asian populations. There is a need for population- and age-appropriate FFM prediction equations
    corecore