Determination of rate constants of drug elimination from the receptor compartment by an infusion method: Neurohypophysial hormones and their structural analogues

ABSTRACT A procedure for measuring the antidiuretic activity of the neurohypophysial hormones and their synthetic structural analogues in the hydrated rat in the dose range of 5–100 antidiuretic microunits is described. The technique of measurement allows the determination of diuresis over one-minute intervals, as well as the total amount of urine excreted over longer periods. The precision of the measurement is greatly increased by the use of a drop divider. The electrical conductivity of the urine is continuously recorded, and the conductivity and creatinine clearance are correlated with the urine flow. These techniques allow the precise determination of parameters such as the half-life of the antidiuretic effect, formal elimination constants, etc.; they can therefore serve for the comparison even of analogues showing qualitative differences in their antidiuretic effects from the chosen standard (arginine or lysine vasopressin), e. g. analogues of the hormonogen type with prolonged effects.

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A general treatment for the kinetics of two consecutive irreversible first-order reactions. Determination of rate constants for the tin(II)-ion catalysed esterification of alkali metal carboxybenzenesulphonates with ethylene glycol

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19781907 ◽

1978 ◽

Vol 43 (7) ◽

pp. 1907-1916 ◽

Cited By ~ 4

Author(s):

Lubomír Nondek ◽

Jaroslav Málek

Keyword(s):

Alkali Metal ◽

Ethylene Glycol ◽

Rate Constants ◽

General Treatment ◽

First Order ◽

Kinetics Of

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Determination of rate constants of redox reactions of second order from current-less potential-time curves by a simplified graphical-numerical method

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19831358 ◽

1983 ◽

Vol 48 (5) ◽

pp. 1358-1367 ◽

Cited By ~ 4

Author(s):

Antonín Tockstein ◽

František Skopal

Keyword(s):

Numerical Method ◽

Explicit Form ◽

Rate Constant ◽

Optimization Algorithm ◽

Rate Constants ◽

Redox Reactions ◽

Second Order ◽

Wide Region ◽

Recurrent Formula

A method for constructing curves is proposed that are linear in a wide region and from whose slopes it is possible to determine the rate constant, if a parameter, θ, is calculated numerically from a rapidly converging recurrent formula or from its explicit form. The values of rate constants and parameter θ thus simply found are compared with those found by an optimization algorithm on a computer; the deviations do not exceed ±10%.

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Determination of the Accurate Values of the Rate Constant and Thermodynamic Parameters for the Rotation About the C(sp2)-C(aryl) Bond; Adamantan-1-yl 3-Bromo-2,4,6-trimethylphenyl Ketone

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19980955 ◽

1998 ◽

Vol 63 (7) ◽

pp. 955-966

Author(s):

Eva Přibylová ◽

Miroslav Holík

Keyword(s):

Thermodynamic Parameters ◽

Shape Analysis ◽

Rate Constants ◽

Line Shape ◽

Microsoft Excel ◽

Hindered Rotation ◽

H Nmr ◽

Line Shape Analysis ◽

Coalescence Temperature

Four programs for the 1H NMR line shape analysis: two commercial - Winkubo (Bruker) and DNMR5 (QCPE 165) and two written in our laboratory - Newton (in Microsoft Excel) and Simtex (in Matlab) have been tested in order to get highly accurate rate constants of the hindered rotation about a single bond. For this purpose four testing criteria were used, two of them were also developed by us. As supplementary determinations the rate constants obtained for the coalescence temperature and for the thermal racemization of chromatographically separated enantiomers were used which fitted well the temperature dependence of the rate constants determined by the line shape analysis. As a test compound adamantan-1-yl 3-bromo-2,4,6-trimethylphenyl ketone was prepared and studied. It was shown that supermodified simplex method used in our algorithm (Simtex), though time consuming, gives the most accurate values of the rate constants and consequently the calculated thermodynamic parameters Ea, ∆H≠, and ∆S≠ lay in relatively narrow confidence intervals.

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Determination of the Nucleophilicity of Tricarbonyliron Coordinated Cyclohepta-1,3,5-triene

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19991770 ◽

1999 ◽

Vol 64 (11) ◽

pp. 1770-1779 ◽

Cited By ~ 6

Author(s):

Herbert Mayr ◽

Karl-Heinz Müller

Keyword(s):

Gibbs Energy ◽

Ambient Temperature ◽

Rate Constants ◽

Second Order ◽

Order Rate ◽

Electrophilic Additions ◽

Kinetics Of

The kinetics of the electrophilic additions of four diarylcarbenium ions (4a-4d) to tricarbonyl(η4-cyclohepta-1,3,5-triene)iron (1) have been studied photometrically. The second-order rate constants match the linear Gibbs energy relationship log k20 °C = s(E + N) and yield the nucleophilicity parameter N(1) = 3.69. It is concluded that electrophiles with E ≥ -9 will react with complex 1 at ambient temperature.

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